# GCN_circulars

GRB_name: GRB190808B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25292
SUBJECT: GRB 190808B: Fermi GBM Final Real-time Localization
DATE:    19/08/08 18:13:38 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 18:03:17 UT on 8 Aug 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190808B (trigger 586980202.431972 / 190808752).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 168.1, Dec = 39.7 (J2000 degrees, equivalent to J2000 11h 12m, 39d 42'), with a statistical uncertainty of 1.4 degrees.

The angle from the Fermi LAT boresight is 72.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190808752/quicklook/glg_skymap_all_bn190808752.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190808752/quicklook/glg_healpix_all_bn190808752.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190808752/quicklook/glg_lc_medres34_bn190808752.gif


GRB_name: GRB190808B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25294
SUBJECT: GRB 190808B: BALROG localization (Fermi Trigger 586980202 / GRB 190808752)
DATE:    19/08/08 18:34:43 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

F. Kunzweiler, B. Biltzinger, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
586980202 at 18:03:17 on 08 Aug. 2019 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 168.0+/-1.3 deg
Decl.(2000.0) = 36.1+/-1.5 deg
We estimate an additional systematic error of 1 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB190808752/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB190808752/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB190808752/json

                        


GRB_name: GRB190726A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25305
SUBJECT: GRB 190726A: Insight-HXMT/HE detection
DATE:    19/08/09 13:00:51 GMT
FROM:    YaoGuang Zheng at IHEP  <zhengyg@ihep.ac.cn>

Y. G. Zheng, C. Cai, Q. Luo, S. Xiao, Q. B. Yi, 
Y. Huang, C. K. Li, G. Li, X. B. Li, J. Y. Liao, S. L. Xiong,
C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, A. M. Zhang, 
Y. F. Zhang, X. F. Lu, C. L. Zou (IHEP), Y. J. Jin, 
Z. Zhang (THU), T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, 
M. Wu, Y. P. Xu, S. N. Zhang (IHEP), 
report on behalf of the Insight-HXMT team:

At 2019-07-26T15:24:59.20 (T0), Insight-HXMT/HE detected 
GRB 190726A (trigger ID: HEB190726642) in a routine search of the data, 
which was also triggered by Fermi/GBM (GCN #25154).

The Insight-HXMT/HE light curve mainly consists of a single  
pulse with a duration (T90) of 2.94 s measured from T0-2.19 s. 
The 1-ms peak rate, measured from T0-1.91 s, is 1319 cnts/sec. 
The total counts from this burst is 3047 counts. 
URL_LC: http://www.hxmt.org/images/GRB/HEB190726642_lc.jpg 

All measurements above are made with the CsI detectors operating in the 
regular mode with the energy range of about 80-800 keV (deposited energy). 
Only gamma-rays with energy greater than about 200 keV can penetrate 
the spacecraft and leave signals in the CsI detectors installed inside 
of the telescope. 

Insight-HXMT is the first Chinese space X-ray telescope, which was 
funded jointly by the China National Space Administration (CNSA) and 
the Chinese Academy of Sciences (CAS). 
More information about it could be found at: 
http://www.hxmt.org.


GRB_name: GRB190810A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25310
SUBJECT: GRB 190810A: Fermi GBM Final Real-time Localization
DATE:    19/08/10 16:22:23 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 16:12:01 UT on 10 Aug 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190810A (trigger 587146326.24257 / 190810675).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 192.8, Dec = -38.7 (J2000 degrees, equivalent to J2000 12h 51m, -38d 42'), with a statistical uncertainty of 17.0 degrees.

The angle from the Fermi LAT boresight is 115.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190810675/quicklook/glg_skymap_all_bn190810675.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190810675/quicklook/glg_healpix_all_bn190810675.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190810675/quicklook/glg_lc_medres34_bn190810675.gif


GRB_name: GRB190810A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25312
SUBJECT: IPN triangulation of GRB 190810A (short)
DATE:    19/08/11 19:27:19 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

K. Hurley, on behalf of the IPN,

I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin,
on behalf of the HEND-Odyssey GRB team,

D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, A. Kozlova,
and T. Cline on behalf of the Konus-Wind team,

A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
on behalf of the Fermi GBM team,

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,

S. Barthelmy, J. Cummings, H. Krimm, and D. Palmer,
on behalf of the Swift-BAT team, and

W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr,
on behalf of the GRS-Odyssey GRB team, report:

The short-duration GRB 190810A (The Fermi-GBM team, GCN 25310)
was detected by Fermi (GBM trigger 587146326), INTEGRAL (SPI-ACS),
Mars-Odyssey (HEND), Konus-Wind, and Swift (BAT),
at about 58321 s UT (16:12:01).
The burst was outside the coded field of view of the BAT.

We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
   192.049 (12h 48m 12s) -28.504 (-28d 30' 16")
  Corners:
   190.529 (12h 42m 07s) -30.184 (-30d 11' 02")
   193.578 (12h 54m 19s) -26.862 (-26d 51' 42")
   193.486 (12h 53m 57s) -26.776 (-26d 46' 34")
   190.437 (12h 41m 45s) -30.097 (-30d 05' 48")
  ---------------------------------------------
The error box area is about 1804 sq. arcmin, and its maximum
dimension is 4.28 deg (the minimum one is 7.0 arcmin).
The Sun distance was 66 deg.

This box may be improved.

The IPN localization is consistent with, but reduces the area of, the 
Fermi-GBM one.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB190810_T58321/IPN

The Konus-Wind time history and spectrum will be given in a forthcoming
GCN Circular.


GRB_name: GRB190810A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25313
SUBJECT: Konus-Wind observation of GRB 190810A
DATE:    19/08/12 11:39:06 GMT
FROM:    Anna Kozlova at Ioffe Institute  <ann_kozlova@mail.ioffe.ru>

A. Kozlova, S. Golenetskii, R. Aptekar, D. Frederiks,
M. Ulanov, D. Svinkin, A. Tsvetkova, A. Lysenko, and T. Cline
on behalf of the Konus-Wind team, report:

The short-duration GRB 190810A
(IPN triangulation: Hurley et al., GCN 25312)
triggered Konus-Wind at T0=58318.421 s UT (16:11:58.421).

The burst light curve shows a single pulse
which starts at T0-0.1 s and has a total duration of ~0.2 s.

As observed by Konus-Wind, the burst
had a fluence of 2.29(-0.40,+0.85)x10^-6 erg/cm2,
and a 16-ms peak flux, measured from T0-0.042 s,
of 2.23(-0.55,+0.92)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

Since the most intense part of the burst was detected before
the trigger, the spectral analysis was performed using
the KW 3-channel light curve data.

Modeling the KW 3-channel time-integrated spectrum
(from T0-0.098 s to T0+0.088 s)
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
yields alpha = -0.61 (-0.22,+0.27), and Ep = 1120 (-266,+656) keV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB190810_T58321/

All the quoted errors are at the 68% confidence level.
All the quoted values are preliminary.


GRB_name: GRB190805B
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25316
SUBJECT: IPN triangulation of GRB 190805B
DATE:    19/08/13 08:09:10 GMT
FROM:    Anna Kozlova at Ioffe Institute  <ann_kozlova@mail.ioffe.ru>

K. Hurley, on behalf of the IPN,

I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin,
on behalf of the HEND-Odyssey GRB team,

A. Kozlova, S. Golenetskii, R. Aptekar, D. Frederiks, D. Svinkin,
and T. Cline on behalf of the Konus-Wind team,

A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
on behalf of the Fermi GBM team,

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,

and

W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr,
on behalf of the GRS-Odyssey GRB team, report:

The long-duration GRB 190805B
(MAXI/GSC detection: Sato et al., GCN Circ. 25271;
Fermi/GBM detection: Hamburg & Meegan, GCN Circ. 25277)
was detected by Fermi (GBM trigger 586673165), INTEGRAL (SPI-ACS),
Mars-Odyssey (HEND), Konus-Wind and MAXI (GSC) at about 17159 s UT
(04:45:59).

We have triangulated it to a Konus-HEND annulus centered at
RA(2000)=321.552 deg (21h 26m 13s)  Dec(2000)=-16.302 deg (-16d 18' 
08"),
whose radius is 61.012 +/- 0.062 deg (3 sigma).

Only a rectangular error box of the MAXI/GSC position reported
by Sato et al. (GCN Circ. 25271) is consistent with the annulus.
The annulus combined with the MAXI (90 % containment, statistical-only)
localization gives the following error box:
---------------------------------------------
    RA(2000), deg                 Dec(2000), deg
   ---------------------------------------------
   Center:
    212.376 (14h 09m 30s) +19.776 (+19d 46' 32")
   Corners:
    212.356 (14h 09m 25s) +20.078 (+20d 04' 39")
    212.487 (14h 09m 57s) +20.071 (+20d 04' 15")
    212.395 (14h 09m 35s) +19.474 (+19d 28' 25")
    212.265 (14h 09m 03s) +19.480 (+19d 28' 49")
   ---------------------------------------------
The error box area is 267 sq. arcmin (a factor of 16
smaller than that of the MAXI error box), and its maximum
dimension is 38 arcmin (the minimum one is 7 arcmin).
The Sun distance was ~73 deg.

The box is partially covered with the Swift XRT observations
reported by Perri et al. (GCN Circ. 25279).

This box may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB190805_T17159/IPN/


GRB_name: GRB190813A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25317
SUBJECT: GRB 190813A: Fermi GBM Final Real-time Localization
DATE:    19/08/13 12:39:33 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 12:29:09 UT on 13 Aug 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190813A (trigger 587392154.943436 / 190813520).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 106.4, Dec = -23.3 (J2000 degrees, equivalent to J2000 07h 05m, -23d 18'), with a statistical uncertainty of 10.4 degrees.

The angle from the Fermi LAT boresight is 49.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190813520/quicklook/glg_skymap_all_bn190813520.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190813520/quicklook/glg_healpix_all_bn190813520.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190813520/quicklook/glg_lc_medres34_bn190813520.gif


GRB_name: GRB190814A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25319
SUBJECT: GRB 190814A: Fermi GBM Final Real-time Localization
DATE:    19/08/14 20:15:37 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 20:05:22 UT on 14 Aug 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190814A (trigger 587505927.990858 / 190814837).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 60.4, Dec = -60.3 (J2000 degrees, equivalent to J2000 04h 01m, -60d 17'), with a statistical uncertainty of 30.2 degrees.

The angle from the Fermi LAT boresight is 62.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190814837/quicklook/glg_skymap_all_bn190814837.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190814837/quicklook/glg_healpix_all_bn190814837.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190814837/quicklook/glg_lc_medres34_bn190814837.gif


GRB_name: GRB190813A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25334
SUBJECT: IPN triangulation of GRB 190813A (short)
DATE:    19/08/15 10:43:27 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin and K. Hurley, on behalf of the IPN,

A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
on behalf of the Fermi GBM team,

and

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,
report:

The short-duration GRB 190813A (The Fermi GBM team, GCN Circ. 25317)
was detected by Fermi (GBM trigger 587392154) and
INTEGRAL (SPI-ACS), at about 44950 s UT (12:29:10).

We have triangulated this GRB to a GBM-INTEGRAL annulus centered at
RA(2000)=96.795 deg (06h 27m 11s) Dec(2000)=-39.989 deg (-39d 59' 21"),
whose radius is 23.630 +/- 8.231 deg (3 sigma).

The IPN localization is consistent with, but reduces the area of, the 
Fermi-GBM one.

This annulus may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB190813_T44949/IPN/


GRB_name: GRB190814A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25363
SUBJECT: GRB 190814A: Insight-HXMT/HE detection
DATE:    19/08/16 13:00:28 GMT
FROM:    Ce Cai at IHEP  <caice@ihep.ac.cn>

C. Cai, Q. Luo, S. Xiao, Q. B. Yi, Y. G. Zheng, Y. Huang, 
C. K. Li, X. B. Li, G. Li, J. Y. Liao, S. L. Xiong, 
C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, A. M. Zhang, 
Y. F. Zhang, X. F. Lu, C. L. Zou (IHEP), Y. J. Jin, 
Z. Zhang (THU), T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, 
M. Wu, Y. P. Xu, S. N. Zhang (IHEP), 
report on behalf of the Insight-HXMT team:

At 2019-08-14T20:05:21.00 (T0), Insight-HXMT/HE detected 
GRB 190814A (trigger ID: HEB190814837) in a routine search of the data, 
which was also triggered by Fermi/GBM (GCN #25319). 

The Insight-HXMT/HE light curve mainly consists of a single  
pulse with a duration (T90) of 5.08 s measured from T0-0.64 s. 
The 1-ms peak rate, measured from T0+0.16 s, is 718 cnts/sec. 
The total counts from this burst is 2077 counts. 
URL_LC: http://www.hxmt.org/images/GRB/HEB190814837_lc.jpg 

All measurements above are made with the CsI detectors operating in the 
regular mode with the energy range of about 80-800 keV (deposited energy). 
Only gamma-rays with energy greater than about 200 keV can penetrate 
the spacecraft and leave signals in the CsI detectors installed inside 
of the telescope. 

Insight-HXMT is the first Chinese space X-ray telescope, which was 
funded jointly by the China National Space Administration (CNSA) and 
the Chinese Academy of Sciences (CAS). 
More information about it could be found at: 
http://www.hxmt.org.


GRB_name: GRB190813A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25364
SUBJECT: GRB 190813A: Insight-HXMT/HE detection
DATE:    19/08/16 13:04:48 GMT
FROM:    Ce Cai at IHEP  <caice@ihep.ac.cn>

C. Cai, Q. Luo, S. Xiao, Q. B. Yi, Y. G. Zheng, Y. Huang, 
C. K. Li, X. B. Li, G. Li, J. Y. Liao, S. L. Xiong, 
C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, A. M. Zhang, 
Y. F. Zhang, X. F. Lu, C. L. Zou (IHEP), Y. J. Jin, 
Z. Zhang (THU), T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, 
M. Wu, Y. P. Xu, S. N. Zhang (IHEP), 
report on behalf of the Insight-HXMT team:

At 2019-08-13T12:29:09.94 (T0), Insight-HXMT/HE detected 
GRB 190813A (trigger ID: HEB190813520) in a routine search of the data, 
which was also triggered by Fermi/GBM (GCN #25317);
IPN Triangulation (GCN #25334).

The Insight-HXMT/HE light curve mainly consists of a single  
pulse with a duration (T90) of 0.04 s measured from T0-0.05 s. 
The 1-ms peak rate, measured from T0-0.04 s, is 8523 cnts/sec. 
The total counts from this burst is 175 counts. 
URL_LC: http://www.hxmt.org/images/GRB/HEB190813520_lc.jpg 

All measurements above are made with the CsI detectors operating in the 
regular mode with the energy range of about 80-800 keV (deposited energy). 
Only gamma-rays with energy greater than about 200 keV can penetrate 
the spacecraft and leave signals in the CsI detectors installed inside 
of the telescope. 

Insight-HXMT is the first Chinese space X-ray telescope, which was 
funded jointly by the China National Space Administration (CNSA) and 
the Chinese Academy of Sciences (CAS). 
More information about it could be found at: 
http://www.hxmt.org.


GRB_name: GRB190816A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25368
SUBJECT: GRB 190816A: Swift detection of a burst
DATE:    19/08/16 14:56:49 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

K. L. Page (U Leicester), S. D. Barthelmy (GSFC),
P. A. Evans (U Leicester), J.D. Gropp (PSU), N. J. Klingler (PSU),
A. Y. Lien (GSFC/UMBC), F. E. Marshall (NASA/GSFC), M. J. Moss (GWU),
D. M. Palmer (LANL) and A. Tohuvavohu (PSU) report on behalf of the
Neil Gehrels Swift Observatory Team:

At 14:42:24 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 190816A (trigger=920783).  Swift did not slew due to an observing
constraint.  The BAT on-board calculated location is 
RA, Dec 341.193, -29.740, which is 
   RA(J2000)  =  22h 44m 46s
   Dec(J2000) = -29d 44' 23"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a couple peaks
with a total duration of about 30 sec.  The peak count rate
was ~600 counts/sec (15-350 keV), at ~3 sec after the trigger. 

Due to a Moon observing constraint, Swift cannot slew to the BAT
position until 17:11 UT on 2019 August 17. There will thus be no XRT or
UVOT data for this trigger before this time. 

Burst Advocate for this burst is K. L. Page (klp5 AT leicester.ac.uk). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB190817A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25387
SUBJECT: GRB 190817A: Fermi GBM Final Real-time Localization
DATE:    19/08/17 23:02:43 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 22:52:25 UT on 17 Aug 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190817A (trigger 587775150.501982 / 190817953).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 275.2, Dec = -31.1 (J2000 degrees, equivalent to J2000 18h 20m, -31d 06'), with a statistical uncertainty of 11.6 degrees.

The angle from the Fermi LAT boresight is 92.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190817953/quicklook/glg_skymap_all_bn190817953.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190817953/quicklook/glg_healpix_all_bn190817953.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190817953/quicklook/glg_lc_medres34_bn190817953.gif


GRB_name: GRB190816A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25399
SUBJECT: GRB 190816A: Swift-XRT observations
DATE:    19/08/19 08:14:53 GMT
FROM:    Kim Page at U.of Leicester  <klp5@leicester.ac.uk>

A. D'Ai (INAF-IASFPA), D.N. Burrows (PSU), J. D. Gropp (PSU), A.
Tohuvavohu (PSU), J.P. Osborne (U. Leicester), K.L. Page (U.
Leicester), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB) and K. L.
Page (U Leicester) report on behalf of the Swift-XRT team:

We have analysed 3.8 ks of Photon Counting (PC) mode XRT data for the
Swift/BAT-detected burst GRB 190816A (Page et al. GCN Circ. 25368),
collected between T0+141.7 ks and T0+216.6 ks. 

One uncatalogued X-ray source has been detected consistent with being
within 296 arcsec of the Swift/BAT position, it is below the RASS limit
and shows no definitive signs of fading. Therefore, at the present time
we cannot confirm this as the afterglow. Details of this source are
given below:

Source 4:
  RA (J2000):  341.1897  =  22:44:45.53
  Dec (J2000): -29.7577  =  -29:45:27.8
  Error: 4.8 arcsec (radius, 90% conf. [Enhanced position])
  Count-rate: (8.1 [+1.8, -1.7])e-3 ct s^-1   
  Distance: 64 arcsec from Swift/BAT position.
  Flux: (2.67 [+0.60, -0.56])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)

Three uncatalogued sources were also detected too far from the GRB
position to be likely afterglow candidates.

The results of the XRT-team automatic analysis of the XRT observations,
including a position-specific upper limit calculator, are available at
https://www.swift.ac.uk/ToO_GRBs/00920783.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB190816A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25405
SUBJECT: GRB 190816A: Swift-BAT refined analysis
DATE:    19/08/20 00:10:43 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

T. N. Ukwatta (LANL), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), K. L. Page (U Leicester),
T. Sakamoto (AGU), M. Stamatikos (OSU)
(i.e. the Swift-BAT team):

Using the data set from T-862 to T+963 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 190816A (trigger #920783)
(Page et al., GCN Circ. 25368).  The BAT ground-calculated position is
RA, Dec = 341.183, -29.745 deg which is
   RA(J2000)  =  22h 44m 44.0s
   Dec(J2000) = -29d 44' 42.5"
with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 30%.

The mask-weighted light curve shows a weak multi-pulse structure that
starts at ~ T-200 s and ends at ~T+340 s. T90 (15-350 keV) is
375.0 +- 92.9 sec (estimated error including systematics).

The time-averaged spectrum from T-206.5 to T+341.6 sec is best fit by a
simple
power-law model.  The power law index of the time-averaged spectrum is
1.62 +- 0.11.  The fluence in the 15-150 keV band is 9.8 +- 0.6 x 10^-6
erg/cm2.
The 1-sec peak photon flux measured from T+151.57 sec in the 15-150 keV band
is 1.3 +- 0.3 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/920783/BA/


GRB_name: GRB190821A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25427
SUBJECT: GRB 190821A: Swift detection of a burst
DATE:    19/08/21 17:31:00 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

A. D'Ai (INAF-IASFPA), E. Ambrosi (INAF-IASFPA), V. D'Elia (SSDC),
J.D. Gropp (PSU), J. A. Kennea (PSU), N. J. Klingler (PSU),
H. A. Krimm (NSF), S. J. LaPorte (PSU), A. Y. Lien (GSFC/UMBC),
F. E. Marshall (NASA/GSFC), M. J. Moss (GWU),
K. L. Page (U Leicester), D. M. Palmer (LANL), B. Sbarufatti (PSU),
K. K. Simpson (PSU) and A. Tohuvavohu (PSU) report on behalf of the
Neil Gehrels Swift Observatory Team:

At 17:10:03 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 190821A (trigger=921722).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 250.077, -34.022 which is 
   RA(J2000) = 16h 40m 18s
   Dec(J2000) = -34d 01' 16"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a multi-peaked
structure with a duration of about 100 sec.  The peak count rate
was ~2200 counts/sec (15-350 keV), at ~30 sec after the trigger. 

The XRT began observing the field at 17:11:21.8 UT, 78.0 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
uncatalogued X-ray source located at RA, Dec 250.05464, -34.00719 which
is equivalent to:
   RA(J2000)  = 16h 40m 13.11s
   Dec(J2000) = -34d 00' 25.9"
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This
location is 85 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (3.35 x
10^21 cm^-2, Willingale et al. 2013), with an excess column of 3.2
(+2.68/-2.37) x 10^21 cm^-2 (90% confidence). 

The initial flux in the 2.5 s image was 2.95e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 88 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. Because of the density of catalogued stars, further
analysis is required to report an upper limit for any afterglow in the
sub-image. The 8'x8' region for the list of sources generated on-board covers
100% of the XRT error circle. Because of the density of catalogued stars,
further analysis is required to report an upper limit for any afterglow in the
region. No correction has been made for the expected extinction corresponding
to E(B-V) of 0.54. 

Burst Advocate for this burst is A. D'Ai (antonino.dai AT inaf.it). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB190821A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25431
SUBJECT: GRB 190821A: T60 Les Makes optical detection of the afterglow
DATE:    19/08/21 18:13:19 GMT
FROM:    Alain Klotz at IRAP-CNRS-OMP  <Alain.Klotz@free.fr>

Klotz A., Noysena.K., Atteia J.L. (CNRS-OMP-IRAP),
Boer, M., Eymar, L. (CNRS-ARTEMIS),
Gendre B. (UWA - Univ. Western Australia)
Peyrot, A., Teng J.P., Thierry P. (Les Makes observatory)
report:

We imaged the field of GRB 190821A detected by SWIFT
(trigger 921722) with the T60 tele-operated telescope (D=60cm)
located at Les Makes Observatory, Reunion Island, France.

The observations started 790s after the GRB trigger.
On the first image of 120s (Clear filter) we detect the
optical afterglow compatible with the position of XRT
(Lien et al. GCNC 25427).

start  end    R
(sec) (sec)
790   910   18.4 +/- 0.2

Further images are comming.

Magnitudes were estimated with the nearby NOMAD1 stars
and are not corrected for galactic dust extinction.


GRB_name: GRB190821A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25433
SUBJECT: GRB 190821A: MASTER do not see any afterglow candidate 
DATE:    19/08/21 19:01:27 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, F.Balakin, E. Gorbovskoy, V. Kornilov, N.Tyurina, 
P.Balanutsa,A.Kuznetsov, F.Balakin, V. Vladimirov, D. Vlasenko,
I. Gorbunov,D.Zimnukhov, V.Senik, A.Chasovnikov, A.Pozdnyakov, 
A.Chasovnikov, 
V.Topolev, D.Kuvshinov(Lomonosov Moscow State University, SAI, Physics 
Department),
R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias IAC),
R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix 
Aguilar OAFA),
H. Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio 
ICATE),
D. Buckley (South African Astronomical Observatory SAAO),
O. Gress, N.M. Budnev, O.Ershova (Irkutsk State University, API),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo 
Observatory),
V. Yurkov, A. Gabovich, Yu. Sergienko (Blagoveschensk Educational State 
University)

There is known star at Swift XRT position (GCN 25427, GCN 25431).
Its brightnes not changes during 1 hour, after 41 sec after trigger in 
MASTER images (GCN  25429).
This message may be cited.


GRB_name: GRB190821A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25435
SUBJECT: GRB 190821A: Fermi GBM observation
DATE:    19/08/21 21:38:14 GMT
FROM:    Bagrat Mailyan at UAH  <bm0054@uah.edu>

B. Mailyan, S. Lesage  and C. Meegan (all UAH)
report on behalf of the Fermi GBM Team:

"At 17:10:34.08 UT on 21 August 2019, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 190821A (trigger 588100239/ 190821716),
which was also detected by the Swift/BAT (D'Ai et al. 2019, GCN 25427).
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight
at the GBM trigger time is 85 degrees.

The GBM lightcurve shows an initial bright pulse followed
by longer duration emission containing multiple peaks.
with a duration (T90) of about 60 s (50-300 keV).
The time-averaged spectrum from T0-4 s to T0+34 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.7 +/- 0.15 and
the cutoff energy, parameterized as Epeak, is 29 +/- 6 keV.

The event fluence (10-1000 keV) in this time interval is
(2.54 +/- 0.17)E-06 erg/cm^2. The 1-sec peak photon flux
measured starting from T-0.128 s in the 10-1000 keV band
is 4.9 +/- 0.25 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support
Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB190821A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25436
SUBJECT: GRB 190821A: Enhanced Swift-XRT position
DATE:    19/08/21 22:38:34 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 1074 s of XRT Photon Counting mode data and 3 UVOT
images for GRB 190821A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 250.05481, -34.00711 which is equivalent
to:

RA (J2000): 16h 40m 13.15s
Dec (J2000): -34d 00' 25.6"

with an uncertainty of 1.6 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB190821A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25444
SUBJECT: GRB 190821A: Swift-XRT refined Analysis
DATE:    19/08/22 07:29:53 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J. D. Gropp (PSU), A. Tohuvavohu (PSU), J.A. Kennea (PSU), J.P. Osborne
(U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U.
Leicester), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), M.G.
Bernardini (INAF-OAB) and A. D'Ai report on behalf of the Swift-XRT
team:

We have analysed 6.7 ks of XRT data for GRB 190821A (D'Ai et al. GCN
Circ. 25427), from 84 s to 33.9 ks after the  BAT trigger. The data
comprise 290 s in Windowed Timing (WT) mode with the remainder in
Photon Counting (PC) mode. The enhanced XRT position for this burst was
given by Goad et al. (GCN Circ. 25436).

The light curve can be modelled with a series of power-law decays. The
initial decay index is alpha=7.82 (+0.18, -0.87). At T+140 s  the decay
flattens to an alpha of -0.4 (+/-0.5) before breaking again at T+1047 s
to a final decay with index alpha=1.06 (+0.17, -0.16).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.75 (+0.18, -0.11). The
best-fitting absorption column is  consistent with the Galactic value
of 3.3 x 10^21 cm^-2 (Willingale et al. 2013). The counts to observed
(unabsorbed) 0.3-10 keV flux conversion factor deduced from this
spectrum  is 4.4 x 10^-11 (5.9 x 10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      3.3 (+/-1.0) x 10^21 cm^-2
Galactic foreground: 3.3 x 10^21 cm^-2
Excess significance: <1.6 sigma
Photon index:      1.75 (+0.18, -0.11)

If the light curve continues to decay with a power-law decay index of
1.06, the count rate at T+24 hours will be 0.015 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 6.8 x
10^-13 (9.0 x 10^-13) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00921722.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB190821A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25448
SUBJECT: GRB 190821A: MASTER VWFC syncronous optical observations
DATE:    19/08/22 14:09:26 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

F.Balakin, V. Lipunov, E. Gorbovskoy, V. Kornilov, N.Tyurina,
P.Balanutsa,A.Kuznetsov, F.Balakin, V. Vladimirov, D. Vlasenko,
I. Gorbunov,D.Zimnukhov, V.Senik, A.Chasovnikov, A.Pozdnyakov, A.Chasovnikov,
V.Topolev, D.Kuvshinov(Lomonosov Moscow State University, SAI, Physics
Department),
R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias IAC),
R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix
Aguilar OAFA),
H. Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio
ICATE),
D. Buckley (South African Astronomical Observatory SAAO),
O. Gress, N.M. Budnev, O.Ershova (Irkutsk State University, API),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
V. Yurkov, A. Gabovich, Yu. Sergienko (Blagoveschensk Educational State
University)


MASTER-SAAO very wide field cameras (d=82 mm, FOV = 2x384 sq. degree) 
syncronously observed GRB190821A (D'Ai et al. GCN 25427)  position before, 
during and after trigger time. We do not see OT at Swift XRT (Gropp et al. 
GCN 25444) position up to 12 mag.   The syncronous observation movie is 
avalable here:

http://master.sai.msu.ru/static/MASTER_SAAO_GRB190822A.gif

MASTER-SAAO robotic telescope  (Global MASTER-Net: 
http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, 
vol. 2010, 30L)  located in South Africa (South African Astronomical 
Observatory) was pointed to the Swift GRB190821A  errorbox  8 sec after 
notice time and 41 sec after trigger time at 2019-08-21 17:10:44 UT, with 
upper limit up to  18.4 mag (Lipunov et al. GCN 25429; GCN 25433). 
Observations 
started at twilight.  We alse do not see OT at Swift XRT.  The 
observations began at zenit distance =  3 deg. The sun  altitude  is -12.4 
deg.

Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=1111516



This message may be cited.


GRB_name: GRB190821A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25450
SUBJECT: GRB 190821A: Swift/UVOT Upper Limits
DATE:    19/08/22 17:58:31 GMT
FROM:    Kira Simpson at PSU  <kira.simpson1984@gmail.com>

GRB 190821A: Swift/UVOT Upper Limits

K. K. Simpson (PSU) and A. D'Ai (INAF-IASFPA)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 190821A
89 s after the BAT trigger (D'Ai et al., GCN Circ. 25427).
No optical afterglow consistent with the XRT position
(Goad et al. GCN Circ. 25436)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC            89          239          147         >19.1
white               89         5595          344         >19.5
v                 5806         6006          197         >18.3
b                 5191         5390          197         >19.9
u                  303        11409          336         >19.6
w1                9373         9551          175         >18.9
m2                6011         6164          151         >19.7
w2                5602         5801          197         >20.2

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.53 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB190823A
Detection_method: MAXI Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25456
SUBJECT: GRB 190823A: MAXI/GSC detection
DATE:    19/08/23 14:59:48 GMT
FROM:    Motoko Serino at RIKEN/MAXI  <motoko@crab.riken.jp>

W. Iwakiri(Chuo U.), M. Serino(AGU), 
H. Negoro, M. Nakajima, W. Maruyama, M. Aoki, K. Kobayashi (Nihon U.), 
T. Mihara, T. Tamagawa, M. Matsuoka (RIKEN), 
T. Sakamoto,  S. Sugita, H. Nishida, A. Yoshida (AGU), 
Y. Tsuboi,  R. Sasaki, H. Kawai, T. Sato (Chuo U.), 
M. Shidatsu (Ehime U.),
N. Kawai, M. Sugizaki, M. Oeda, K. Shiraishi (Tokyo Tech), 
S. Nakahira, Y. Sugawara, S. Ueno, H. Tomida, M. Ishikawa, N.Isobe, R. Shimomukai, M. Tominaga (JAXA), 
Y. Ueda, A. Tanimoto, S. Yamada, S. Ogawa, K. Setoguchi, T. Yoshitake (Kyoto U.), 
H. Tsunemi, T. Yoneyama, K. Asakura, S. Ide (Osaka U.), 
M. Yamauchi, S. Iwahori, Y. Kurihara, K. Kurogi, K. Miike (Miyazaki U.), 
T. Kawamuro (NAOJ), 
K. Yamaoka (Nagoya U.),
Y. Kawakubo (LSU)
report on behalf of the MAXI team:

The MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source 
at 13:30:22 UT on 2019 August 23.
Assuming that the source flux was constant over the transit,
we obtain the source position at
(R.A., Dec) = (279.278 deg, -43.439 deg) = (18 37 06, -43 26 19) (J2000)
with a 90% C.L. statistical error of 0.17 deg and an additional systematic uncertainty 
of 0.1 deg (90% containment radius).

Without assumptions on the source constancy, we obtain a rectangular error
box for the transient source with the following corners:
(R.A., Dec) = (280.193, -43.737) deg = (18 40 46, -43 44 13) (J2000)
(R.A., Dec) = (280.285, -43.434) deg = (18 41 08, -43 26 02) (J2000)
(R.A., Dec) = (278.903, -43.205) deg = (18 35 36, -43 12 17) (J2000)
(R.A., Dec) = (278.804, -43.508) deg = (18 35 12, -43 30 28) (J2000) 

The X-ray flux averaged over the scan was 322 +- 29 mCrab
(4.0-10.0keV, 1 sigma error).

There was no significant excess flux in the previous transit at UT 11:57
with an upper limit of 20 mCrab.


GRB_name: GRB190823A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25459
SUBJECT: GRB 190823A: Tiled Swift observations
DATE:    19/08/23 17:29:06 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a series of observations, tiled on the sky, of the
MAXI GRB 190823A. Automated analysis of the XRT data will
be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00085

Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. The probability of finding
serendipitous sources, unrelated to the MAXI event is high: any X-ray source
considered to be a probable afterglow candidate will be reported via a GCN Circular
after manual consideration.

Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).

This circular is an official product of the Swift-XRT team.


GRB_name: GRB190824A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25462
SUBJECT: GRB 190824A: Fermi GBM Final Real-time Localization
DATE:    19/08/24 14:56:55 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 14:46:37 UT on 24 Aug 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190824A (trigger 588350802.674684 / 190824616).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 208.1, Dec = -39.7 (J2000 degrees, equivalent to J2000 13h 52m, -39d 42'), with a statistical uncertainty of 1.5 degrees.

The angle from the Fermi LAT boresight is 86.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190824616/quicklook/glg_skymap_all_bn190824616.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190824616/quicklook/glg_healpix_all_bn190824616.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190824616/quicklook/glg_lc_medres34_bn190824616.gif


GRB_name: GRB190824A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25463
SUBJECT: GRB 190824A: Swift detection of a burst
DATE:    19/08/24 15:03:25 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

V. D'Elia (SSDC), E. Ambrosi (INAF-IASFPA), S. D. Barthelmy (GSFC),
D. N. Burrows (PSU), J.D. Gropp (PSU), N. J. Klingler (PSU),
A. Y. Lien (GSFC/UMBC), F. E. Marshall (NASA/GSFC),
K. L. Page (U Leicester) and D. M. Palmer (LANL) report on behalf of
the Neil Gehrels Swift Observatory Team:

At 14:46:39 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 190824A (trigger=922107).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 215.329, -41.902, which is 
   RA(J2000)  =  14h 21m 19s
   Dec(J2000) = -41d 54' 07"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows multiple peaks
with a total duration of about 120 sec.  The peak count rate
was ~3200 counts/sec (15-350 keV), at ~1 sec after the trigger. 

The XRT began observing the field at 14:55:24.0 UT, 524.4 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source with an enhanced position: RA, Dec 215.3045,
-41.8943 which is equivalent to:
   RA(J2000)  = 14h 21m 13.09s
   Dec(J2000) = -41d 53' 39.3"
with an uncertainty of 2.3 arcseconds (radius, 90% containment). This
location is 71 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper. No
spectrum from the promptly downlinked event data is yet available to
determine the column density. 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 568 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.12. 

Burst Advocate for this burst is V. D'Elia (delia AT ssdc.asi.it). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB190821A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25464
SUBJECT: GRB 190821A: Swift-BAT refined analysis
DATE:    19/08/24 15:57:08 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

S. D. Barthelmy (GSFC), J. R. Cummings (CPI),
A. D'Ai (INAF-IASFPA), H. A. Krimm (NSF),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU), T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):

Using the data set from T-239 to T+963 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 190821A (trigger #921722)
(D'Ai et al., GCN Circ. 25427).  The BAT ground-calculated position is
RA, Dec = 250.070, -34.027 deg which is
   RA(J2000)  =  16h 40m 16.9s
   Dec(J2000) = -34d 01' 35.5"
with an uncertainty of 1.3 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 83%.

The mask-weighted light curve shows a multi-peaked structure that starts
at ~T-3 s and ends at ~T+60 s. The highest peak occurs at ~T+30 s.
T90 (15-350 keV) is 57.1 +- 2.6 sec (estimated error including systematics).

The time-averaged spectrum from T-3.3 to T+59.5 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.03 +- 0.10.  The fluence in the 15-150 keV band is 2.4 +- 0.1 x 10^-6
erg/cm2.
The 1-sec peak photon flux measured from T+29.98 sec in the 15-150 keV band
is 2.8 +- 0.3 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/921722/BA/


GRB_name: GRB190824A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25466
SUBJECT: GRB 190824A: Enhanced Swift-XRT position
DATE:    19/08/24 20:05:19 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 1213 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 190824A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 215.30490, -41.89382 which is equivalent
to:

RA (J2000): 14h 21m 13.18s
Dec (J2000): -41d 53' 37.8"

with an uncertainty of 1.5 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB190824A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25469
SUBJECT: GRB 190824A: Fermi GBM observation
DATE:    19/08/24 22:06:37 GMT
FROM:    Cori Fletcher at USRA  <cfletcher@usra.edu>

C. Fletcher (USRA) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 14:46:37.67 UT on 24 August 2019, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 190824A (trigger 588350802 / 190824616),
which was also detected by the Swift/BAT (D'Elia et al. 2019, GCN 25463)
The Fermi GBM Final Real-time Localization (GCN 25462) is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 82 degrees.

The GBM light curve consists of an initial bright pulse followed by
multiple peaks with a duration (T90) of about 109 s (50-300 keV).
The time-averaged spectrum from T0-1.024 s to T0+107.52 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.38 +/- 0.06 and
the cutoff energy, parameterized as Epeak, is 247 +/- 55 keV

The event fluence (10-1000 keV) in this time interval is
(1.4 +/- 0.1)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+2.05 s in the 10-1000 keV band
is 7.9 +/- 0.4 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB190824A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25470
SUBJECT: GRB 190824A: Swift-XRT refined Analysis
DATE:    19/08/25 03:13:15 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

A. Tohuvavohu (PSU), J.A. Kennea (PSU), K.L. Page (U. Leicester), A.P.
Beardmore (U. Leicester), P.A. Evans (U. Leicester), P. D'Avanzo
(INAF-OAB), M.G. Bernardini (INAF-OAB), E. Ambrosi  (INAF-IASFPA) , B.
Sbarufatti (PSU) and V. D'Elia report on behalf of the Swift-XRT team:

We have analysed 6.1 ks of XRT data for GRB 190824A (D'Elia et al. GCN
Circ. 25463), from 524 s to 34.2 ks after the  BAT trigger. The data
are entirely in Photon Counting (PC) mode. The enhanced XRT position
for this burst was given by Osborne et al. (GCN Circ. 25466).

The light curve can be modelled with a power-law decay with a decay
index of alpha=0.64 (+/-0.04).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.19 (+0.22, -0.21). The
best-fitting absorption column is  1.29 (+0.25, -0.22) x 10^22 cm^-2,
in excess of the Galactic value of 1.0 x 10^21 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 4.7 x 10^-11 (1.1 x 10^-10) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      1.29 (+0.25, -0.22) x 10^22 cm^-2
Galactic foreground: 1.0 x 10^21 cm^-2
Excess significance: 8.9 sigma
Photon index:      2.19 (+0.22, -0.21)

If the light curve continues to decay with a power-law decay index of
0.64, the count rate at T+24 hours will be 0.030 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.4 x
10^-12 (3.3 x 10^-12) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00922107.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB190825A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25471
SUBJECT: GRB 190825A: Fermi GBM Final Real-time Localization
DATE:    19/08/25 04:17:15 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 04:06:56 UT on 25 Aug 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190825A (trigger 588398821.139798 / 190825171).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 330.5, Dec = -81.2 (J2000 degrees, equivalent to J2000 22h 02m, -81d 12'), with a statistical uncertainty of 93.9 degrees.

The angle from the Fermi LAT boresight is 14.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190825171/quicklook/glg_skymap_all_bn190825171.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190825171/quicklook/glg_healpix_all_bn190825171.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190825171/quicklook/glg_lc_medres34_bn190825171.gif


GRB_name: GRB190816A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25473
SUBJECT: GRB 190816A: Swift-XRT afterglow detection
DATE:    19/08/25 04:57:43 GMT
FROM:    Kim Page at U.of Leicester  <klp5@leicester.ac.uk>

A. D'Ai (INAF-IASFPA), D.N. Burrows (PSU), J. D. Gropp (PSU), A.
Tohuvavohu (PSU), J.P. Osborne (U. Leicester), K.L. Page (U.
Leicester), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB) and P.A.
Evans (U. Leicester) report on behalf of the Swift-XRT team:

Swift-XRT has conducted further observations of the field of the
Swift/BAT-detected burst GRB 190816A (Ukwatta et al. GCN Circ. 25405).
The observations now extend from T0+141.7 ks to T0+723.4 ks. The source
previously reported by D'Ai et al. (GCN Circ. 25399), "Source 4", is
fading with 3-sigma significance, and is therefore likely the GRB
afterglow. Using 267 s of PC mode data and 1 UVOT image, we find an
enhanced XRT position (using the XRT-UVOT alignment and matching UVOT
field sources to the USNO-B1 catalogue): RA, Dec = 341.18949, -29.75761
which is equivalent to:

RA (J2000): 22h 44m 45.48s
Dec(J2000): -29d 45' 27.4"

with an uncertainty of 4.9 arcsec (radius, 90% confidence). This
position is 64 arcsec from the Swift/BAT position.  The source is
fading with alpha >0.5.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00920783.
The results of the full analysis of the XRT observations are available
at https://www.swift.ac.uk/ToO_GRBs/00920783.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB190823A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25476
SUBJECT: GRB 190823A: Swift-XRT observations
DATE:    19/08/25 19:04:38 GMT
FROM:    Elena Ambrosi at INAF-IASF  <elena.ambrosi@inaf.it>

E. Ambrosi (INAF-IASFPA), A. DAi (INAF-IASFPA) and V. D Elia (ASDC)

report on behalf of the Swift-XRT team:


Swift-XRT has performed follow-up observations of the MAXI-detected

burst GRB 190823A (Iwakiri et al. GCN circ. 25456) in a series of

observations tiled on the sky.

Total exposure time is 1.8 ks, distributed over 7 tiles. The data were
collected

between T0+12.1 ks and T0+18 ks.


One uncatalogued X-ray source has been detected, with the following details:


RA (J2000):      279.68736d = 18:38:44.97

Dec (J2000):    -43.52789d = -43:31:40.4

Error: 8.6 arcsec (radius, 90% conf.)

Count-rate:   4.1 (+1.7, -1.3) Ã—10^-2 ct s^ -1

Distance: 18.6 arcmin from MAXI position


The results of the XRT-team automatic analysis of the tiled XRT

observations, including a position-specific upper limit calculator, are

available at https://www.swift.ac.uk/xrt_products/TILED_GRB00085/ .


This circular is an official product of the Swift-XRT team.


GRB_name: GRB190824A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25479
SUBJECT: GRB 190824A: Swift/UVOT Upper Limits
DATE:    19/08/26 12:55:49 GMT
FROM:    Kira Simpson at PSU  <kira.simpson1984@gmail.com>

GRB 190824A: Swift/UVOT Upper Limits

K. K. Simpson (PSU) and V. D'Elia (SSDC)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 190824A
568 s after the BAT trigger (D'Elia et al., GCN Circ. 25463).
No optical afterglow consistent with the XRT position
(Osborne et al., GCN Circ. 25466)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC           568          718          147         >19.9
white              568         1721          389         >19.9
v                 1058         6747          196         >17.8
b                  799         1697           97         >18.9
u                  774         1672           97         >19.3
w1                 750         1647           97         >18.4
m2                 725         1622           97         >19.6
w2                 849         1742           74         >18.7

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.12 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB190824A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25482
SUBJECT: GRB 190824A, Swift-BAT refined analysis 
DATE:    19/08/26 20:50:27 GMT
FROM:    Hans Krimm at NSF/NASA-GSFC  <hkrimm@nsf.gov>

J. R. Cummings (CPI) S. D. Barthelmy (GSFC), V. D'Elia (SSDC),
H. A. Krimm (NSF), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-230 to T+963 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 190824A (trigger #922107)
(D'Elia, et al., GCN Circ. 25463).  The BAT ground-calculated position is
RA, Dec = 215.323, -41.900 deg which is 
  RA(J2000)  =  14h 21m 17.6s 
  Dec(J2000) = -41d 53' 59.5" 
with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 28%.

The mask-weighted light curve shows three main peaks, each with underlying 
substructure.  The first peak is from ~T-80 sec to T-60 sec.  The second,
largest, peak is from ~T-10 sec to T+50 sec, and the third peak is from
~T+85 sec to T+110 sec.   T90 (15-350 keV) is 169.4 +- 5.9 sec (estimated 
error including systematics).

The time-averaged spectrum from T-71.9 to T+114.6 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.62 +- 0.08.  The fluence in the 15-150 keV band is 8.5 +- 0.4 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+0.12 sec in the 15-150 keV band
is 5.0 +- 0.5 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/922107/BA/


GRB_name: GRB190827A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25489
SUBJECT: GRB 190827A: Fermi GBM Final Real-time Localization
DATE:    19/08/27 11:23:01 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 11:12:48 UT on 27 Aug 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190827A (trigger 588597173.546288 / 190827467).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 175.8, Dec = 46.5 (J2000 degrees, equivalent to J2000 11h 43m, 46d 30'), with a statistical uncertainty of 1.0 degrees.

The angle from the Fermi LAT boresight is 6.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190827467/quicklook/glg_skymap_all_bn190827467.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190827467/quicklook/glg_healpix_all_bn190827467.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190827467/quicklook/glg_lc_medres34_bn190827467.gif


GRB_name: GRB190827A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25490
SUBJECT: GRB 190827A: BALROG localization (Fermi Trigger 588597173 / GRB 190827467)
DATE:    19/08/27 11:36:00 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

J. Burgess , B. Biltzinger, F. Kunzweiler, F. Berlato, & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
588597173 at 11:12:48 on 27 Aug. 2019 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 175.8+/-0.9 deg
Decl.(2000.0) = 41.5+/-1.1 deg
We estimate an additional systematic error of 1 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB190827467/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB190827467/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB190827467/json

                        


GRB_name: GRB190828A
Detection_method: MAXI Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25502
SUBJECT: GRB 190828A: MAXI/GSC detection
DATE:    19/08/28 08:44:15 GMT
FROM:    Satoshi Sugita at Aoyama Gakuin U.  <sugita@phys.aoyama.ac.jp>

S. Sugita,  H. Nishida, M. Serino (AGU), H. Negoro (Nihon U.), K.
Asakura (Osaka U.),
M. Nakajima, W. Maruyama, M. Aoki, K. Kobayashi (Nihon U.),
T. Mihara, T. Tamagawa, M. Matsuoka (RIKEN),
T. Sakamoto, A. Yoshida (AGU),
W. Iwakiri, Y. Tsuboi,  R. Sasaki, H. Kawai, T. Sato (Chuo U.),
M. Shidatsu (Ehime U.),
N. Kawai, M. Sugizaki, M. Oeda, K. Shiraishi (Tokyo Tech),
S. Nakahira, Y. Sugawara, S. Ueno, H. Tomida, M. Ishikawa, N.Isobe, R.
Shimomukai, M. Tominaga (JAXA),
Y. Ueda, A. Tanimoto, S. Yamada, S. Ogawa, K. Setoguchi, T. Yoshitake
(Kyoto U.),
H. Tsunemi, T. Yoneyama, S. Ide (Osaka U.),
M. Yamauchi, S. Iwahori, Y. Kurihara, K. Kurogi, K. Miike (Miyazaki U.),
T. Kawamuro (NAOJ),
K. Yamaoka (Nagoya U.),
Y. Kawakubo (LSU)
report on behalf of the MAXI team:

The MAXI/GSC nova alert system triggered a bright uncatalogued X-ray
transient source at 07:58:01 UT on 2019 August 28.
Assuming that the source flux was constant over the transit,
we obtain the source position at
(R.A., Dec) = (58.011 deg, 46.448 deg) = (03 52 02, +46 26 52)  (J2000)
with a 90% C.L. statistical error of 0.25 deg and an additional
systematic uncertainty of 0.1 deg (90% containment radius).

Without assumptions on the source constancy, we obtain a rectangular error
box for the transient source with the following corners:
(56.303, 46.041) deg = (03 45 12, +46 02 27) (J2000)
(56.644, 45.605) deg = (03 46 34, +45 36 17) (J2000)
(60.044, 46.816) deg = (04 00 10, +46 48 57) (J2000)
(59.724, 47.262) deg = (03 58 53, +47 15 43) (J2000)

The X-ray flux averaged over the scan was 193 +- 27 mCrab
(4.0-10.0keV, 1 sigma error).


GRB_name: GRB190828B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25516
SUBJECT: GRB 190828B: Fermi GBM Final Real-time Localization
DATE:    19/08/28 13:10:04 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 12:59:59 UT on 28 Aug 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190828B (trigger 588690004.456526 / 190828542).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 246.6, Dec = 24.6 (J2000 degrees, equivalent to J2000 16h 26m, 24d 36'), with a statistical uncertainty of 1.0 degrees.

The angle from the Fermi LAT boresight is 17.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190828542/quicklook/glg_skymap_all_bn190828542.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190828542/quicklook/glg_healpix_all_bn190828542.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190828542/quicklook/glg_lc_medres34_bn190828542.gif


GRB_name: GRB190828B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25517
SUBJECT: GRB 190828B: Swift detection of a burst
DATE:    19/08/28 13:15:52 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

S. Dichiara (NASA/GSFC/UMCP), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), M. G. Bernardini (INAF-OAB),
A. A. Breeveld (UCL-MSSL), D. N. Burrows (PSU), A. D'Ai (INAF-IASFPA),
P. D'Avanzo (INAF-OAB), P. A. Evans (U Leicester), J.D. Gropp (PSU),
J. A. Kennea (PSU), N. J. Klingler (PSU), F. E. Marshall (NASA/GSFC),
A. Melandri (INAF-OAB), K. L. Page (U Leicester), B. Sbarufatti (PSU),
M. H. Siegel (PSU) and A. Tohuvavohu (PSU) report on behalf of the
Neil Gehrels Swift Observatory Team:

At 12:59:59.42 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 190828B (trigger=922808).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 251.818, 27.237 which is 
   RA(J2000) = 16h 47m 16s
   Dec(J2000) = +27d 14' 12"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a multi-peaked
structure with a duration of about 40 sec.  The peak count rate
was ~3000 counts/sec (15-350 keV), at ~10 sec after the trigger. 

The XRT began observing the field at 13:00:54.1 UT, 54.7 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source with an enhanced position: RA, Dec
251.8317, 27.2808 which is equivalent to:
   RA(J2000)  = 16h 47m 19.60s
   Dec(J2000) = +27d 16' 50.9"
with an uncertainty of 2.2 arcseconds (radius, 90% containment). This
location is 163 arcseconds from the BAT onboard position, within the
BAT error circle. This position may be improved as more data are
received; the latest position is available at
http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 6.84
x 10^20 cm^-2 (Willingale et al. 2013). 

The initial flux in the 2.5 s image was 2.12e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 63 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.10. 

Burst Advocate for this burst is S. Dichiara (dichiara AT umd.edu). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB190828C
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25519
SUBJECT: GRB 190828C: Fermi GBM Final Real-time Localization
DATE:    19/08/28 14:54:48 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 14:44:26 UT on 28 Aug 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190828C (trigger 588696271.447674 / 190828614).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 191.2, Dec = -58.8 (J2000 degrees, equivalent to J2000 12h 44m, -58d 47'), with a statistical uncertainty of 1.2 degrees.

The angle from the Fermi LAT boresight is 61.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190828614/quicklook/glg_skymap_all_bn190828614.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190828614/quicklook/glg_healpix_all_bn190828614.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190828614/quicklook/glg_lc_medres34_bn190828614.gif


GRB_name: GRB190828C
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25520
SUBJECT: GRB 190828C: BALROG localization (Fermi Trigger 588696271 / GRB 190828614)
DATE:    19/08/28 15:07:58 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

 J. Burgess, B. Biltzinger, F. Kunzweiler, F. Berlato & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
588696271 at 14:44:26 on 28 Aug. 2019 were automatically fitted for spectrum
and sky location with the official BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 189.1+/-0.9 deg
Decl.(2000.0) = -59.7+/-0.6 deg
We estimate an additional systematic error of 1 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB190828614/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB190828614/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB190828614/json

                        


GRB_name: GRB190828B
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25521
SUBJECT: GRB 190828B: Enhanced Swift-XRT position
DATE:    19/08/28 16:08:02 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 1594 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 190828B, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 251.83127, +27.28091 which is equivalent
to:

RA (J2000): 16h 47m 19.51s
Dec (J2000): +27d 16' 51.3"

with an uncertainty of 1.7 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB190828B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25524
SUBJECT: GRB 190828B: Dabancheng-0.5m optical upper limit
DATE:    19/08/28 16:31:06 GMT
FROM:    Dong Xu at NAOC/CAS  <dxu@nao.cas.cn>

B.Y. Yu, X. Liu, D. Xu, Z.P. Zhu (NAOC), J.H. Liu (XAO), X. Gao (Urumqi 
No.1 Senior High School), Z.B. Zhang (XJTS) report:

We observed the field of GRB 190828B (Dichiara et al., GCN 25517) using 
the Half-Meter Telescope (HMT-0.5m) located at Dabancheng, Xinjiang, 
China. We obtained 5x60 s unfiltered frames, started at 13:56:32 UT on 
2019-08-28, i.e., 56.5 min after the burst.

No optical source is detected at the XRT position (Dichiara et al., 
GCN25517) in our stacked image, down to a limiting magnitude of R~17.8, 
calibrated with the nearby SDSS field.


GRB_name: GRB190828D
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25528
SUBJECT: GRB 190828D: A long GRB detected by INTEGRAL
DATE:    19/08/28 19:53:38 GMT
FROM:    Sandro Mereghetti at IASF-Milano/INAF  <sandro.mereghetti@inaf.it>

S.Mereghetti (INAF, IASF-Milano), D.Gotz (CEA, Saclay),  E.Bozzo,
C.Ferrigno, V.Savchenko (ISDC, Versoix), L.Ducci (IAAT, Germany and ISDC,
Versoix) and J.Borkowski (CAMK, Torun) report:

a gamma ray burst lasting about 20 s has been detected by IBAS in the
IBIS/ISGRI data at 18:48:30  UT of August 28, 2019.

The refined coordinates (J2000) are:

R.A.=   251.9247 deg
DEC.=   -24.5498 deg

with an uncertainty of  2.5   arcmin (90% c.l.).

The burst had a peak flux of  0.7    counts/cm2/s (20-200 keV, 1-s
integration  time) and a fluence in the same energy range of about 7e-7
erg/cmq.

A plot of the light curve will  be posted at
http://ibas.iasf-milano.inaf.it/IBAS_Results.html


GRB_name: GRB190828A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25529
SUBJECT: GRB 190828A: Tiled Swift observations
DATE:    19/08/28 21:25:46 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a series of observations, tiled on the sky, of the
MAXI GRB 190828A. Automated analysis of the XRT data will
be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00086

Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. The probability of finding
serendipitous sources, unrelated to the MAXI event is high: any X-ray source
considered to be a probable afterglow candidate will be reported via a GCN Circular
after manual consideration.

Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).

This circular is an official product of the Swift-XRT team.


GRB_name: GRB190828B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25534
SUBJECT: GRB 190828B: Swift-BAT refined analysis
DATE:    19/08/28 23:33:26 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

H. A. Krimm (NSF), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), S. Dichiara (NASA/GSFC/UMCP),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
(i.e. the Swift-BAT team):

Using the data set from T-239 to T+962 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 190828B (trigger #922808)
(Dichiara et al., GCN Circ. 25517).  The BAT ground-calculated position is
RA, Dec = 251.838, 27.287 deg which is
   RA(J2000)  =  16h 47m 21.2s
   Dec(J2000) = +27d 17' 12.9"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.

The mask-weighted light curve shows a multi-peak structure that starts
at ~T-40 s and ends at ~T+50 s. There are roughly three main peaks
that occurs at ~T0, ~T+11 s, and ~T+31 s, respectively.
T90 (15-350 keV) is 66.6 +- 6.2 sec (estimated error including systematics).

The time-averaged spectrum from T-42.4 to T+53.3 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.29 +- 0.07.  The fluence in the 15-150 keV band is 4.2 +- 0.2 x 10^-6
erg/cm2.
The 1-sec peak photon flux measured from T+10.74 sec in the 15-150 keV band
is 2.3 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/922808/BA/


GRB_name: GRB190828B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25535
SUBJECT: GRB 190828B: Fermi GBM observation
DATE:    19/08/29 03:23:48 GMT
FROM:    Oliver J Roberts at USRA/NASA  <oliver.roberts@nasa.gov>

O.J. Roberts (USRA/MSFC), E. Bissaldi (INFN Bari) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 12:59:59.46 UT on 28 August 2019, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 190828B (trigger 588690004 / 190828542),
which was also detected by Swift (Dichiara et al. 2019, GCN 25517 )

The Fermi GBM Final Real-time Localization (GCN 25516) is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 18 degrees.

The GBM light curve consists of multiple, bright peaks with a
duration (T90) of about 55 s (50-300 keV).
The time-averaged spectrum from T0-34 s to T0+46 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -0.99 +/- 0.06 and
the cutoff energy, parameterized as Epeak, is 237 +/- 22 keV

The event fluence (10-1000 keV) in this time interval is
(1.24 +/- 0.06)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+10.6 s in the 10-1000 keV band
is 3.9 +/- 0.2 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB190823A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25541
SUBJECT: GRB 190823A: AstroSat CZTI detection
DATE:    19/08/29 09:14:15 GMT
FROM:    Ramkrishna Gaikwad at IUCAA/AstroSat  <ramkrishna@iucaa.in>

R. Gaikwad, M. Chavan, V. Sharma and D. Bhattacharya and A. Vibhute (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data showed the detection of a GRB 190823A, which was also detected by Swift-XRT (E. Ambrosi et al., GCN #25476) and Tiled Swift observations (Evans P. A. et al., GCN #25459).

The source was clearly detected in the 40-200 keV energy range. The light curve shows multiple pulses of emission with the strongest peak at 2019-08-23 13:30:05.0 UT. The measured peak count rate associated with the burst is 287 cts/s above the background in the combined data of four quadrants, with a total of 1445 cts. The local mean background count rate was 460 cts/s. Using cumulative rates, we measure a T90 of 7.3 s.

It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.

CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.


GRB_name: GRB190828A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25542
SUBJECT: GRB 190828A: Swift-XRT observations
DATE:    19/08/29 09:46:09 GMT
FROM:    Paolo D'Avanzo at INAF - OAB  <paolo.davanzo@inaf.it>

J.A. Kennea (PSU), A.P. Beardmore (U. Leicester), J.P. Osborne (U.
Leicester), M.G. Bernardini (INAF-OAB), E. Ambrosi  (INAF-IASFPA) , M.
Capalbi (INAF-IASFPA), B. Sbarufatti (PSU), D.N. Burrows (PSU) and P.A.
Evans (U. Leicester) report on behalf of the Swift-XRT team:

Swift-XRT has performed follow-up observations of the MAXI-detected
burst GRB 190828A (Sugita et al. GCN Circ. 25502) in a series of
observations tiled on the sky. The total exposure time is 1.3 ks,
distributed over 7 tiles; the maximum exposure at a single sky location
was 393 s. The data were collected between T0+48.4 ks and T0+49.8 ks,
and are entirely in Photon Counting (PC) mode. 

No X-ray sources have been detected. The 3-sigma upper limit in the
field (not including the regions where the tiles overlap) ranges from
~0.02 to ~0.15 ct s^-1, corresponding to a 0.3-10 keV observed flux of
9.9e-13 to 5.8e-12 erg cm^-2 s^-1 (assuming a typical GRB spectrum).

The results of the XRT-team automatic analysis of the tiled XRT
observations, including a position-specific upper limit calculator, are
available at https://www.swift.ac.uk/xrt_products/TILED_GRB00086.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB190828B
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25544
SUBJECT: GRB 190828B: Swift/UVOT Upper Limits
DATE:    19/08/29 13:01:37 GMT
FROM:    Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>

S. R. Oates (U.Warwick) and S. Dichiara (NASA/GSFC/UMCP)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 190828B
63 s after the BAT trigger (Dichiara et al., GCN Circ. 25517).
No optical afterglow consistent with the XRT position
(Beardmore et al. GCN Circ. 25521)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC            63          213          147         >20.8
u_FC               275          525          246         >20.1
white               63         1717          411         >21.4
v                  605         1767          136         >19.1
b                  530         1693          117         >20.0
u                  275         1668          363         >20.4
w1                 654         1644          117         >19.2
m2                 630         5626          259         >19.4
w2                 580         1743          136         >19.3

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.10 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB190828B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25546
SUBJECT: GRB 190828B: Swift-XRT refined Analysis
DATE:    19/08/29 13:16:02 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester), K.L. Page (U.
Leicester), E. Ambrosi (INAF-IASFPA) , M. Capalbi (INAF-IASFPA), M.
Perri (ASDC), B. Sbarufatti (PSU), D.N. Burrows (PSU), J. D. Gropp
(PSU) and S. Dichiara report on behalf of the Swift-XRT team:

We have analysed 5.8 ks of XRT data for GRB 190828B (Dichiara et al.
GCN Circ. 25517), from 60 s to 74.7 ks after the  BAT trigger. The data
comprise 90 s in Windowed Timing (WT) mode with the remainder in Photon
Counting (PC) mode. The enhanced XRT position for this burst was given
by Beardmore et al. (GCN Circ. 25521).

The light curve can be modelled with a series of power-law decays. The
initial decay index is alpha=2.4 (+/-0.4). At T+98.4 s the decay
flattens to an alpha of -1.5 (+0.0, -1.4). The light curve breaks again
at T+110 s to a decay with alpha=3.5 (+0.7, -0.4),  and  again at T+217
s s to alpha=-0.24 (+0.16, -0.20),  before a final break at T+1028 s s
after which the decay index is 0.96 (+/-0.04).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.56 (+0.11, -0.09). The
best-fitting absorption column is  7.8 (+3.8, -1.0) x 10^20 cm^-2,
consistent with the Galactic value of 6.8 x 10^20 cm^-2 (Willingale et
al. 2013). The PC mode spectrum has a photon index of 1.91 (+/-0.10)
and a best-fitting absorption column of 1.25 (+0.29, -0.27) x 10^21
cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 3.6 x 10^-11 (4.4 x 10^-11) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      1.25 (+0.29, -0.27) x 10^21 cm^-2
Galactic foreground: 6.8 x 10^20 cm^-2
Excess significance: 3.4 sigma
Photon index:      1.91 (+/-0.10)

If the light curve continues to decay with a power-law decay index of
0.96, the count rate at T+24 hours will be 0.035 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.3 x
10^-12 (1.6 x 10^-12) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00922808.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB190828B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25548
SUBJECT: GRB 190828B: optical upper limit from 0.5m Savelli Robotic Telescope
DATE:    19/08/29 14:35:27 GMT
FROM:    Andrea Melandri at INAF-OAB  <andrea.melandri@brera.inaf.it>

A. Brosio (Oss. Astr. Savelli), A. Melandri (INAF-OAB), E. Palazzi (INAF-OAS), L. Nicastro (INAF-OAS), M.A. Tripodi (Oss. Astr. Savelli), S. Savaglio (UniCal) on behalf of a larger collaboration report:


We observed the field of GRB 190828B (Dichiara et al., GCN 25517) with the 0.5m Savelli Robotic Telescope (SRT) located at the Osservatorio Astronomico Lilio (Savelli, Italy). The observations were performed starting on 2019 August 28 at 19:19:22 UT (i.e. about 6.3 hours after the burst) and consisted of 24x300s exposures in the r-sdss band. 

No optical counterpart is detected nearby the XRT enhanced position (Beardmore et al., GCN 25521) in our stacked image, down to a 5sigma limiting magnitude of r>20.5, at a mean time of about 7.48 hours after the GRB. Calibration was performed against the SDSS catalog.


GRB_name: GRB190828B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25550
SUBJECT: GRB 190828B: VLT/X-shooter optical afterglow candidate
DATE:    19/08/29 16:58:17 GMT
FROM:    Kasper Elm Heintz at Univ. of Iceland and DAWN/NBI  <keh14@hi.is>

J. P. U. Fynbo (DAWN/NBI), K. E. Heintz (Univ. of Iceland), D. B. Malesani (DTU space), and D. A. Perley (LJMU), report on behalf of the Stargate collaboration:

We imaged the field of the Swift (Dichiara et al., GCN 25517) and Fermi-GBM (Roberts et al., GCN 25536) detected GRB 190828B with the ESO-VLT/X-shooter acquisition camera between 00:03:44 and 00:22:49 UT on August 29 (i.e. 11.15 hr after the trigger). From the combined images, obtained with a total integration time of 210 sec, we identify a faint source within the XRT error circle with magnitude r = 23.55 +/- 0.15 AB mag, calibrated from the photometry of nearby field stars as listed in the Pan-STARRS archival data. To verify whether this source is the afterglow or host galaxy of the GRB, a second epoch of images is required.

We acknowledge the ESO observing staff at Paranal, especially Alain Smette, Camila Navarrete and Linda Schmidtobreick.

[GCN OPS NOTE(31aug19): Per author's request, the "Title:" string was removed from the SUBJECT: line.]


GRB_name: GRB190829A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25551
SUBJECT: GRB 190829A: Fermi GBM Final Real-time Localization
DATE:    19/08/29 20:06:10 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 19:55:53 UT on 29 Aug 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190829A (trigger 588801358.125594 / 190829830).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 45.6, Dec = -7.1 (J2000 degrees, equivalent to J2000 03h 02m, -7d 05'), with a statistical uncertainty of 2.2 degrees.

The angle from the Fermi LAT boresight is 30.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190829830/quicklook/glg_skymap_all_bn190829830.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190829830/quicklook/glg_healpix_all_bn190829830.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190829830/quicklook/glg_lc_medres34_bn190829830.gif


GRB_name: GRB190829A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25552
SUBJECT: GRB 190829A: Swift detection of a burst consistent with a galaxy at z=0.08
DATE:    19/08/29 20:25:37 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

S. Dichiara (NASA/GSFC/UMCP), M. G. Bernardini (INAF-OAB),
D. N. Burrows (PSU), P. D'Avanzo (INAF-OAB), C. Gronwall (PSU),
J.D. Gropp (PSU), J. A. Kennea (PSU), N. J. Klingler (PSU),
H. A. Krimm (NSF), N. P. M. Kuin (UCL-MSSL), S. J. LaPorte (PSU),
A. Melandri (INAF-OAB), K. L. Page (U Leicester), D. M. Palmer (LANL),
M. H. Siegel (PSU), K. K. Simpson (PSU) and A. Tohuvavohu (Toronto)
report on behalf of the Neil Gehrels Swift Observatory Team:

At 19:56:44.60 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 190829A (trigger=922968).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 44.540, -8.968 which is 
  RA(J2000) = 02h 58m 10s
  Dec(J2000) = -08d 58' 03"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a smaller peak
at ~T-50 seconds followed by the main peak around T~0 with a 
duration of about 15 sec.  The peak count rate
was ~1500 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 19:58:21.9 UT, 97.3 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
uncatalogued X-ray source with an enhanced position: RA, Dec 44.5440,
-8.9579 which is equivalent to:
   RA(J2000)  = 02h 58m 10.57s
   Dec(J2000) = -08d 57' 28.6"
with an uncertainty of 2.0 arcseconds (radius, 90% containment). This
location is 39 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data does not constrain the column density. 

The initial flux in the 2.5 s image was 7.75e-10 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 106 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.05. 

This GRB was also reported by the Fermi GBM Team (GCN #25551), 
at the time of the first peak. 

We note the presence of a galaxy SDSS J025810.28-085719.2 with z=0.07914 
centered at a distance of 10 arcseconds from the XRT location. 
http://skyserver.sdss.org/dr14/en/tools/explore/Summary.aspx?id=1237652899156721762

Burst Advocate for this burst is S. Dichiara (dichiara AT umd.edu). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25555
SUBJECT: GRB 190829A: Dabancheng-0.5m optical afterglow detection
DATE:    19/08/29 21:36:30 GMT
FROM:    Dong Xu at NAOC/CAS  <dxu@nao.cas.cn>

D. Xu, B.Y. Yu, Z.P. Zhu (NAOC) report on behalf of a larger collaboration:

We observed the field of GRB 190829A (Dichiara et al., GCN 25552) using 
the Half Meter Telescope (HMT-0.5m) located at Dabancheng, Xinjiang, 
China. Observations started at 20:49:03 UT on 2019-08-29 (i.e., 52.3 min 
after the burst), and a series of 150s unfiltered frames and photometry 
is still ongoing.

We detected an uncatalogued and evolving optical source at coordinates

R.A. (J2000) = 2:58:10.580
Dec. (J2000) = -8:57:29.82

with an uncertainty of ~0.3 arcsec, fully consistent with the XRT error 
circle (Dichiara et al., GCN 25552). Preliminary analysis gives 
m(r)~16.0 mag for the source in our first image. We thus conclude that 
this source is the optical counterpart of the bust at z=0.079.


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25558
SUBJECT: GRB 190829A:: MASTER-net bright and decay OT detection
DATE:    19/08/29 22:35:55 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, F.Balakin,  E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, 
A.Kuznetsov, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik,
T.Pogrosheva,  D.Kuvshinov
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),

H.Levato
(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),

R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),

D. Buckley
(South African Astronomical Observatory),

O.A. Gres, N.M. Budnev, O.Ershova
(Irkutsk State University, API),

A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich, Yu. Sergienko
(Blagoveschensk Educational State University)


MASTER-Kislovodsk robotic telescope  (Global MASTER-Net: 
http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, 
vol. 2010, 30L)  located in Russia (Lomonosov MSU, Kislovodsk Solar 
Station of Pulkovo observatory) was pointed to the SWIFT GRB190829.83 
(trigger No 922968,Dichiara et al GCN 25552) errorbox 
1215 sec after notice time and 1239 sec after trigger time at 2019-08-29 
20:17:23 UT, with upper limit up to  18.6 mag. The observations began at 
zenit distance = 89 deg. The sun  altitude  is -36.2 deg.

MASTER-SAAO robotic telescope  located in South Africa (South African 
Astronomical Observatory) was pointed to the SWIFT GRB190829.83 errorbox 
1215 sec after notice time and 6757 sec after trigger time at 2019-08-29 
21:49:21 UT, with upper limit up to  17.3 mag. The observations began at 
zenit distance = 76 deg. The sun  altitude  is -64.5 deg.

MASTER-Tavrida robotic telescope  located in Russia (Lomonosov MSU, SAI 
Crimea astronomical station) was pointed to the SWIFT GRB190829.83 
errorbox  1215 sec after notice time and 6766 sec after trigger time at 
2019-08-29 21:49:30 UT, with upper limit up to  16.4 mag. The observations 
began at zenit distance = 79 deg. The sun  altitude  is -36.7 deg.

The galactic latitude b = -60 deg., longitude l = 98 deg.


Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=1119490

MASTER-Kislovodsk auto-detection system discovered OT source at (RA, Dec) 
= 02h 58m 10.51s -08d 57m 27.2s on 2019-08-29.86841 UT.
The OT unfiltered magnitude is 14.9m (limit 17.2m).

The OT is seen in 12 images.
The OT decay on ~2 magnitudes  during first 2 hours of observations. 
So this OT could be a GRB 190829A optical counterpart.

We have reference image without OT on 2014-11-20.85262 UT with unfiltered 
magnitude limit 20.7m.


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25560
SUBJECT: GRB 190829A: GROWTH India detection of afterglow
DATE:    19/08/29 22:55:45 GMT
FROM:    Varun Bhalerao at Indian Inst of Tech  <varunb@iitb.ac.in>

H. Kumar, V. Bhalerao (IITB), Jigmat Stanzin, G C Anupama, S. Barwe (IIAP) report on behalf of the GROWTH-India collaboration:

We observed the field of 190829A (Fermi GBM Team, GCN 2555; Dichiara et al., GCN 25552) with the GROWTH-India telescope. We obtained multiple 500 second exposures in g and r, starting 51 minutes after the event. We clearly detect an optical afterglow in all filters. Preliminary photometry values in g band are quoted below.

     JD           dt_minutes   ap_mag   Mag_err
2458725.366  51.16  16.93   0.01
2458725.372  59.80  17.21   0.02
2458725.394  91.48  18.00   0.12
2458725.400 100.12  18.08   0.04

The data are consistent with a power-law decline with a slope of 1.6. In addition, we also obtained an r band data point at JD 2458725.385, detecting the afterglow clearly with m_r = 16.475 +- 0.013, broadly consistent with Xu et al. (GCN 25555)

We caution that these photometry values are contaminated by flux from the host galaxy, and the afterglow brightness has been overestimated. 

The GROWTH India Telescope (GIT) is a 70-cm telescope with a 0.7 degree field of view, set up by the Indian Institute of Astrophysics and the Indian Institute of Technology Bombay with support from the Indo-US Science and Technology Forum (IUSSTF) and the Science and Engineering Research Board (SERB) of the Department of Science and Technology (DST), Government of India (https://sites.google.com/view/growthindia/). It is located at the Indian Astronomical Observatory (Hanle), operated by the Indian Institute of Astrophysics (IIA).

[Per author's request, the inclusion of discussion of a second GRB (GRB190701A) was an accident.
It has been removed from the archived copies.]


GRB_name: GRB190830A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25561
SUBJECT: GRB 190830A: Fermi GBM Final Real-time Localization
DATE:    19/08/30 00:43:05 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 00:32:48 UT on 30 Aug 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190830A (trigger 588817973.260436 / 190830023).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 111.9, Dec = -23.8 (J2000 degrees, equivalent to J2000 07h 27m, -23d 48'), with a statistical uncertainty of 7.5 degrees.

The angle from the Fermi LAT boresight is 106.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190830023/quicklook/glg_skymap_all_bn190830023.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190830023/quicklook/glg_healpix_all_bn190830023.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190830023/quicklook/glg_lc_medres34_bn190830023.gif


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25563
SUBJECT: GRB 190829A: NOT optical afterglow detection and spectroscopy
DATE:    19/08/30 03:42:22 GMT
FROM:    Daniel Perley at Liverpool JMU  <d.a.perley@ljmu.ac.uk>

K. E. Heintz (Univ. of Iceland), J. P. U. Fynbo (DAWN/NBI), P. Jakobsson 
(Univ. of Iceland), D. Xu (NAOC), D. A. Perley (LJMU), D. B. Malesani 
(DTU space), and J. Viuho (NOT), report on behalf of a larger 
collaboration:

We observed the Swift-detected GRB 190829A (Dichiara et al., GCN 25552) 
with the Nordic Optical Telescope (NOT) equipped with AlFOSC. We 
obtained 3x300s r-band images at a mid-time of 02:03:52 UT on August 30 
(i.e. 6.1 hr post-burst). We clearly detect the optical counterpart 
reported by Xu et al. (GCN 25555), superimposed on the SDSS galaxy 
J025810.28-085719.2 at z=0.08 as noted previously.  We measure a 
preliminary magnitude of r(AB) = 18.9 +/- 0.1 for this source, 
calibrated against photometry of nearby field stars from the Pan-STARRS 
catalog.

Following the imaging sequence, we obtained a series of spectra with an 
integration time of 4x600s using grism 4 (covering 320-960 nm), 
beginning at 02:27:42 UT. The spectrum shows a featureless red 
continuum, with no clear absorption lines to identify the redshift. 
Since the continuum is detected at all observed wavelengths we can place 
a limit on the redshift of z < 1.8.









DisclaimerNone


GRB_name: GRB190830B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25564
SUBJECT: GRB 190830B: Fermi GBM Final Real-time Localization
DATE:    19/08/30 06:31:13 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 06:20:46 UT on 30 Aug 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190830B (trigger 588838851.35002 / 190830264).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 159.2, Dec = -54.7 (J2000 degrees, equivalent to J2000 10h 36m, -54d 42'), with a statistical uncertainty of 9.8 degrees.

The angle from the Fermi LAT boresight is 118.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190830264/quicklook/glg_skymap_all_bn190830264.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190830264/quicklook/glg_healpix_all_bn190830264.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190830264/quicklook/glg_lc_medres34_bn190830264.gif


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25565
SUBJECT: GRB 190829A: 10.4m GTC spectroscopy
DATE:    19/08/30 06:40:25 GMT
FROM:    Alberto J. Castro-Tirado at IAA-CSIC  <ajct@iaa.es>

A. F. Valeev (SAO-RAS), A. J. Castro-Tirado, Y.-D. Hu, and E. 
Fernandez-Garcia (IAA-CSIC), V. V. Sokolov (SAO-RAS), I. Carrasco and A. 
Castellon (UMA) D. Garcia Alvarez (GRANTECAN, IAC, ULL) and M. Rivero 
(GRANTECAN), on behalf of a larger collaboration, report:

Following the detection of GRB 190829A by Fermi (GCNC 25551) and Swift 
(Dichiara et al., GCN 25552), we obtained optical imaging and 
spectroscopy of the proposed optical counterpart (Xu et al. GCNC 25555, 
Lipunov et al. GCNC 25558, Kumar et al. GCNC 25560) covering the range 
3700-10000 A with the 10.4m GTC telescope equipped with OSIRIS in La 
Palma (Spain) starting on Aug 30, 03:00 UT.

On Aug 30, 3:00 UT, we measure i = 18.42 +/- 0.05. The GRB 190829A 
optical afterglow spectrum displays a red continuum consistent with the 
NOT results (Heintz et al. GCNC 25563). We find the Ca H & K doublet 
(3933 & 3969 A) in absorption in the afterglow spectrum, which also 
shows the emission lines of the underlying SDSS galaxy 
J025810.28-085719.2 at redshift z = 0.0785 +/- 0.005, thus supporting 
the physical association between GRB 190829A and the galaxy.

Thus, GRB 198029A is one of the nearest GRBs detected to date. 
Multiwavelength follow-up observations are encouraged.

This message can be quoted.


GRB_name: GRB190829A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25566
SUBJECT: GRB190829A: Detection of VHE gamma-ray emission with H.E.S.S. 
DATE:    19/08/30 07:08:37 GMT
FROM:    Fabian Schussler at CEA  <fabian.schussler@cea.fr>

M. de Naurois on behalf of the H.E.S.S. collaboration

The H.E.S.S. array of imaging atmospheric Cherenkov telescopes was used to carry out follow-up observations of the afterglow of GRB 190829A (Dichiara et al., GCN 25552). At a redshift of z = 0.0785 +/- 0.005 (A.F. Valeev et al., GCN 25565) this is one of the nearest GRBs detected to date. H.E.S.S. Observations started July 30 at 00:16 UTC (i.e. T0 + 4h20), lasted until 3h50 UTC and were taken under good conditions. A preliminary onsite analysis of the obtained data shows a >5sigma gamma-ray excess compatible with the direction of GRB190829A. Further analyses of the data are on-going and further H.E.S.S. observations are planned. We strongly encourage follow-up at all wavelengths.

H.E.S.S. is an array of five imaging atmospheric Cherenkov telescopes for the detection of very-high-energy gamma-ray sources and is located in the Khomas Highlands in Namibia. It was constructed and is operated by researchers from Armenia, Australia, Austria, France, Germany, Ireland, Japan, the Netherlands, Poland, South Africa, Sweden, UK, and the host country, Namibia. For more details see https://www.mpi-hd.mpg.de/hfm/HESS/


GRB_name: GRB190829A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25567
SUBJECT: GRB 190829A: Enhanced Swift-XRT position
DATE:    19/08/30 08:42:57 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 882 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 190829A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 44.54402, -8.95837 which is equivalent
to:

RA (J2000): 02h 58m 10.57s
Dec (J2000): -08d 57' 30.1"

with an uncertainty of 1.8 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB190829A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25568
SUBJECT: GRB 190829A: Swift-XRT refined Analysis
DATE:    19/08/30 09:06:05 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), M. Capalbi
(INAF-IASFPA), M. Perri (ASDC), V. D'Elia (ASDC), D.N. Burrows (PSU),
J. D. Gropp (PSU), A. Tohuvavohu (PSU), A.P. Beardmore (U. Leicester)
and S. Dichiara report on behalf of the Swift-XRT team:

We have analysed 10 ks of XRT data for GRB 190829A (Dichiara et al. GCN
Circ. 25552), from 103 s to 39.7 ks after the  BAT trigger. The data
comprise 697 s in Windowed Timing (WT) mode with the remainder in
Photon Counting (PC) mode. The enhanced XRT position for this burst was
given by Evans et al. (GCN Circ. 25567).

The late-time light curve (from T0+4.8 ks) can be modelled with an
initial power-law decay with an index of alpha=2.6 (+0.7, -1.1),
followed by a break at T+144 s to an alpha of 0.33 (+0.09, -0.11).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.17 (+0.20, -0.19). The
best-fitting absorption column is  7.4 (+1.7, -1.5) x 10^21 cm^-2, in
excess of the Galactic value of 5.6 x 10^20 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 2.46 (+0.21, -0.20)
and a best-fitting absorption column of 1.53 (+0.23, -0.21) x 10^22
cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 4.5 x 10^-11 (1.5 x 10^-10) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      1.53 (+0.23, -0.21) x 10^22 cm^-2
Galactic foreground: 5.6 x 10^20 cm^-2
Excess significance: 11.5 sigma
Photon index:      2.46 (+0.21, -0.20)

If the light curve continues to decay with a power-law decay index of
0.33, the count rate at T+24 hours will be 0.95 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 4.2 x
10^-11 (1.4 x 10^-10) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00922968.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25569
SUBJECT: GRB 190829A: GROND detection of the Optical/NIR Afterglow
DATE:    19/08/30 09:16:48 GMT
FROM:    Ting-Wan Chen at MPE  <jchen@mpe.mpg.de>

T.-W. Chen, J. Bolmer (both MPE Garching), A. Nicuesa Guelbenzu and S.Klose (both TLS Tautenburg) report: 

We observed the field of GRB 190829A (SWIFT trigger 922968; Dichiara et al. GCN 25552) simultaneously in gâ€™râ€™iâ€™zâ€™JHKs with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La Silla Observatory (Chile). 

Observations started at 05:41 UT on 30 August 2019, 9.73 hr after the GRB trigger. They were performed at an average seeing of 1.75" and at an average airmass of 1.6. We detect the optical/NIR afterglow  (Xu et al., GCN 25555; Lipunov et al., GCN 25558; Kumar et al., GCN 25560; Heintz et al., GCN 25563; Valeev et al., GCN 25565) at coordinates RA, DEC (J2000) = 2:58:10.51, -8:57:28.1 (+/- 0.3 arcsec) with the following preliminary AB magnitudes:

gâ€™ = 20.30 +/- 0.03,
râ€™ = 19.34 +/- 0.03,
iâ€™ = 18.77 +/- 0.03,
zâ€™ = 18.21 +/- 0.03,
J = 17.34 +/- 0.06,
H = 16.68 +/- 0.06,
Ks = 16.40 +/- 0.08.

Given magnitudes are calibrated against SDSS as well as 2MASS field stars and are not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V)=0.04 mag in the direction of the burst (Schlafly & Finkbeiner 2011).

We acknowledge excellent help in obtaining these data from Sam Kim on La Silla.  


GRB_name: GRB190829A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25570
SUBJECT: GRB 190829A: Swift/UVOT detection of an optical afterglow with a rise
DATE:    19/08/30 10:42:30 GMT
FROM:    Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>

S. R. Oates (U.Warwick) and S. Dichiara (NASA/GSFC/UMCP)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 190829A
106 s after the BAT trigger (Dichiara et al., GCN Circ. 25552).
An optical afterglow consistent with the XRT position
(Evans et al. GCN Circ. 25567) and the optical afterglow reported by 
Dabancheng-0.5m (Xu et al. GCN Circ. 25555), MASTER-net
(Lipunov et al. GCN Circ. 25558), GROWTH (Kumar et al. GCN Circ. 25560),
NOT (Heintz et al. GCN Circ. 25563), GTC (Valeev et al. GCN Circ. 25565)
and GROND (Chen et al. GCN Circ. 25569) is detected in the initial UVOT exposures.

An inital rise is observed in the UVOT images peaking at ~1400s. The afterglow
is detected in white, v, b, u and w1, but is not detected in the initial m2 and w2 exposures.
For m2 and w2 we provide upper limits from a summed image created from 4 individual
exposures closest to the peak.

Preliminary detections and 3 sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and other early exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC    106              256            147          20.05 +/- 0.17 
u_FC           264        514            246          19.95 +/- 0.27
white           546        566              19          19.48 +/- 0.30 
v                  771        791              19          17.52 +/- 0.28 
b                1149      1168              19          17.29 +/- 0.15 
u                  845        865              19          18.40 +/- 0.36 
w1             1099      1638              78          18.54 +/- 0.35
m2             1075      1614              78          > 18.5            
w2             1026      1565              78          > 18.7

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.05 in the direction of the burst
(Schlegel et al. 1998). In addition, the underlying host galaxy has not
been subtracted.


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25573
SUBJECT: GRB 190829A:: Global MASTER-net optical clear and polarization observations scheduler  and some spiculations
DATE:    19/08/30 11:29:38 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, E. Gorbovskoy, F.Balakin,  V.Kornilov, 
N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Vladimirov, D. Vlasenko,
I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva,  D.Kuvshinov, 
A.Chasovnikov, V.Topolev, A.Posdnyakov
(Lomonosov Moscow State University, SAI, Physics Department),

V. Yurkov, A. Gabovich, Yu. Sergienko
(Blagoveschensk Educational State University)

A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),


R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),

H.Levato
(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),

R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),

D. Buckley
(South African Astronomical Observatory),

O.A. Gres, N.M. Budnev, O.Ershova
(Irkutsk State University, API),



MASTER-Amur robotic telescope (Global MASTER-Net: 
http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, 
vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical 
University) was pointed to the  GRB190829A (Fermi GCN 25551 )  55 sec 
after Swift trigger  time (Dichiara et al., GCN 25552) at  2019-08-29 19:57:39   UT. The 
5-sigma image limit has been about 14.5 mag


MASTER-Kislovodsk robotic telescope was pointed to the  GRB190829A  by 
FERMI GBM coordinates  15 s after trigger time at 2019-08-29 19:56:59 in 
two polarizations.
The Swift BAT position was 2 degree below horison at this time on 
MASTER-Kislovodsk in two polarizations.  The first image at Swift BAT 
position was obtained 909 s after trigger at 2019-08-29 20:11:53, but due to extrimelly high zenith 
distance (89.5 degree) this images has no stars. The first images with 
stars  was obtained  1239 s after trigger at 2019-08-29 20:17:23 (zenith 
distance 88.7).

The both FERMI-GBM and Swift BAT position was below horisont at 
MASTER-SAAO,  MASTER-Tavrida and MASTER-OAFA sites. Thus, automatic 
pointing was not possible.

MASTER-SAAO robotic telescope  located in South Africa (South African 
Astronomical Observatory) was pointed to the GRB190829A errorbox  6757 sec 
after trigger time at 2019-08-29 21:49:21 UT, with upper limit up to  21.3 
mag. The observations began at zenit distance = 76 deg. The sun  altitude 
is -64.5 deg.

MASTER-Tavrida robotic telescope  located in Russia (Lomonosov MSU, SAI 
Crimea astronomical station) was pointed to the  GRB190829.83 errorbox 
6766 sec after trigger time at 2019-08-29 21:49:30 UT, with upper limit up 
to  18.5 mag. The observations began at zenit distance = 79 deg. The sun 
altitude  is -36.7 deg.

MASTER-OAFA robotic telescope  located in Argentina (OAFA observatory of 
San Juan National University) joined  to the  GRB190829A observations 
27862 sec after trigger time at 2019-08-30 03:41:06 UT, with upper limit 
up to  19.8 mag. The observations began at zenit distance = 77 deg. The 
sun  altitude  is -64.8 deg.
Observation with the MASTER-OAFA telescope continues.


Swift team  noted   the presence of a galaxy SDSS J025810.28-085719.2 
(PGC997094) with z=0.07914 centered at a distance of 10 arcseconds from 
the XRT location.

The aftergrlow was detected indipendingly by ( Xu et al. GCNC 25555,
Lipunov et al. GCNC 25558).
We see object with 3.1E 7.5S arcsec ofsset from the galaxy center.


Optical afterglow spectrum displays a red 
continuum  (Valeev et al., 25565) consistent with the
NOT results (Heintz et al. GCNC 25563) at redshift z = 0.0785 +/- 0.005 
which coincided with PGC Galaxy.

Very late brightening (up to 1 hour after trigger)  in our data, says 
about the unusual nature of this phenomenon. By the way, after 
the maximum of the brightness of the brightness decreases linearly with 
time!

Obviously, this fact indicates the affinity of the galaxy and the 
gamma-evant.

If a very probable connection between the gamma-ray burst and the nearby 
galaxy PGC997094 at a distance of ~ 320 Megaparsec  and the lack of
an LVC alert can make an  important conclusion (VML):
as expected, the collapse of the progenitor core proceeds through the slow 
(on the scale of the radial fall time) compression of the quasicylindrical 
object - the spinar (Lipunov & Gorbovskoy, 2007, ApJ, vol. 665, 
97; Lipunov & Gorbovskoy, MNRAS, 2008, vol. 383, 1397;
Lipunova et al., MNARS, 2009, vol. 397; 1695 .

The one of the automatic detection images is available at
master.sai.msu.ru/static/OT/GRB190829.jpg

You can see the tools of the MASTER robot in Kislovodsk. From left to 
right: the image corresponds to the specified time, the next frame of the 
DSS,  the next is difference between the new and the reference frame, 
frame from  SDSS.

Below are two frames of today's observation. Then a logarithm frame. 
Finaly, old reference frame.

Ruduction is continue.
This message can be cited.


GRB_name: GRB190829A
Detection_method: Fermi LAT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25574
SUBJECT: GRB 190829A: Fermi-LAT Upper Limits
DATE:    19/08/30 12:37:54 GMT
FROM:    Frederic Piron at CNRS/IN2P3/LUPM  <piron@in2p3.fr>

F. Piron (CNRS/IN2P3/LUPM), F. Longo (Univ. and INFN Trieste), M. 
Axelsson (KTH and Stockholm Univ.), M. Arimoto (Kanazawa Univ.), J. L. 
Racusin (NASA/GSFC) and E. Bissaldi (Politecnico and INFN Bari) report 
on behalf of the Fermi-LAT Collaboration:

Fermi-LAT observed the position of GRB 190829A, which was detected by 
Fermi-GBM (GCN Circ. 25551), Swift (GCN Circ. 25552), and H.E.S.S. (GCN 
Circ. 25566). The GRB position was in the LAT field of view at the time 
of the GBM trigger (T0= 2019-08-29 19:55:53 UTC), and remained visible 
until ~T0+1100 s. No high-energy gamma-ray emission was detected by the 
LAT in the initial interval or any subsequent intervals, including 
during the H.E.S.S. observations.

LAT upper limits (95% confidence level, 100 MeV - 1 GeV), assuming a 
photon index of -2.0, cover the following intervals:

Time Interval         Energy Flux (erg/cm2/s)       Photon Flux (ph/cm2/s)

0-1.1 ks                      5.3e-10                       1.3e-6
0-10 ks                       3.2e-10                       7.9e-7
10-30 ks                      1.4e-10                       3.5e-7
15-30 ks (H.E.S.S. interval)  1.8e-10                       4.3e-7


The Fermi-LAT point of contact for this burst is Frederic Piron 
(piron@in2p3.fr).

The Fermi-LAT is a pair conversion telescope designed to cover the 
energy band from 20 MeV to greater than 300 GeV.  It is the product of 
an international collaboration between NASA and DOE in the U.S. and many 
scientific institutions across France, Italy, Japan and Sweden.


GRB_name: GRB190829A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25575
SUBJECT: GRB 190829A: Fermi GBM detection
DATE:    19/08/30 12:43:01 GMT
FROM:    Suraj Poolakkil at UAH  <sp0076@uah.edu>

S. Lesage (UAH), S. Poolakkil (UAH), C. Fletcher (USRA), C. Meegan (UAH)
and A. Goldstein (USRA) report on behalf of the Fermi GBM Team:

"At 19:55:53.13 UT on 29 August 2019, the Fermi Gamma-Ray Burst Monitor
(GBM)
triggered and located GRB 190829A (trigger 588801358 / 190829830),
which was also detected by the Swift/XRT (Dichiara et al. 2019, GCN 25552)
The Fermi GBM Final Real-time Localization (GCN 25551) is consistent with
the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 33
degrees.

The GBM light curve shows an initial pulse followed by a brighter
peak, with a duration (T90) of about 63 s (50-300 keV).
The time-averaged spectrum for the initial pulse,
from T0s to T0+4.0 s, is best fit by
a power law function with an exponential
high-energy cutoff.  The power law index is -1.41 +/- 0.08 and
the cutoff energy, parameterized as Epeak, is 130 +/- 20 keV.
The time-averaged spectrum for the second pulse,
from T0+47.1 s to T0+61.4 s, is best fit by
a Band function with Epeak = 11 +/- 1 keV,
alpha = -0.92 +/- 0.62, and beta = -2.51 +/- 0.01.

The fluence (10-1000 keV) of the two peaks is
(1.267 +/- 0.015)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+51.2 s in the 10-1000 keV band
is ~25.6 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support
Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB190828D
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25576
SUBJECT: GRB 190828D: Insight-HXMT/HE detection
DATE:    19/08/30 12:59:32 GMT
FROM:    Qi Luo at IHEP  <luoqi@ihep.ac.cn>

J. M. Yao, Y. G. Zheng, C. Cai, Q. Luo, S. Xiao, Q. B. Yi, 
Y. Huang, C. K. Li, G. Li, X. B. Li, J. Y. Liao, S. L. Xiong,
C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, A. M. Zhang, 
Y. F. Zhang, X. F. Lu, C. L. Zou (IHEP), Y. J. Jin, 
Z. Zhang (THU), T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, 
M. Wu, Y. P. Xu, S. N. Zhang (IHEP), 
report on behalf of the Insight-HXMT team:

At 2019-08-28T18:48:33.70 (T0), Insight-HXMT/HE detected 
GRB 190828D (trigger ID: HEB190828783) in a routine search of the data, 
which was also triggered by INTEGRAL (GCN #25528).

The Insight-HXMT/HE light curve mainly consists of multiple 
pulses with a duration (T90) of 5.21 s measured from T0+0.03 s. 
The 1-ms peak rate, measured from T0+0.03 s, is 4001 cnts/sec. 
The total counts from this burst is 5857 counts. 
URL_LC: http://www.hxmt.org/images/GRB/HEB190828783_lc.jpg 

All measurements above are made with the CsI detectors operating in the 
regular mode with the energy range of about 80-800 keV (deposited energy). 
Only gamma-rays with energy greater than about 200 keV can penetrate 
the spacecraft and leave signals in the CsI detectors installed inside 
of the telescope. 

Insight-HXMT is the first Chinese space X-ray telescope, which was 
funded jointly by the China National Space Administration (CNSA) and 
the Chinese Academy of Sciences (CAS). 
More information about it could be found at: 
http://www.hxmt.org.


GRB_name: GRB190829A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25577
SUBJECT: GRB 190829A: AGILE ratemeters detection and MCAL upper limits
DATE:    19/08/30 13:16:54 GMT
FROM:    Carlotta Pittori at ASI SSDC, INAF-OAR  <carlotta.pittori@ssdc.asi.it>

C. Pittori (SSDC, and INAF/OAR), A. Ursi (INAF/IAPS), M. Tavani
(INAF/IAPS, and Univ. Roma Tor Vergata), M. Cardillo, C. Casentini,
G. Piano (INAF/IAPS), F. Lucarelli, F. Verrecchia (SSDC, and INAF/OAR),
A. Bulgarelli, V. Fioretti, N. Parmiggiani (INAF/OAS-Bologna),
M. Pilia (INAF/OA-Cagliari), F. Longo (Univ. Trieste, and INFN Trieste),
report on behalf of the AGILE Team:

AGILE observed the long GRB 190829A at T0 = 2019-08-29 19:55:53 (UT)
first reported by Fermi GBM (GCN 25551) and by Swift (GCN 25552).
The scientific ratemeters of the Anti-Coincidence (50-200 keV) and
Super-AGILE (SA; 18-60 keV) detected the burst.
The GRB 190829A was also seen at VHE gamma-ray energy by
H.E.S.S.(GCN 25566).

The GRB location was fully accessible to the AGILE MCAL, but no trigger
occured around +/- 100 sec from T0.

Three-sigma upper limits (ULs) are obtained for a 1 s integration
time at different celestial positions from a minimum of
1.16E-06 erg cm^-2 to a maximum of 1.36E-06 erg cm^-2
(assuming as spectral model a single power law with photon index 1.5).

The AGILE-MCAL detector is a CsI detector with a 4 pi FoV, sensitive in
the energy range 0.4-100 MeV.

The GRB 190829A  position has optimal exposure also in the AGILE
field of View of the Gamma-Ray Imaging Detector (GRID) and
further analyses are still in progress.


GRB_name: GRB190829A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25578
SUBJECT: GRB 190829A: AGILE-GRID upper limits
DATE:    19/08/30 14:42:21 GMT
FROM:    Giovanni Piano at INAF-IAPS  <giovanni.piano@inaf.it>

G. Piano (INAF/IAPS), F. Verrecchia (SSDC, and INAF/OAR), M. Tavani
(INAF/IAPS, and Univ. Roma Tor Vergata),  C. Pittori (SSDC, and INAF/OAR),
A. Ursi, M. Cardillo, C. Casentini (INAF/IAPS), F. Lucarelli (SSDC, and
INAF/OAR),
A. Bulgarelli, V. Fioretti, N. Parmiggiani (INAF/OAS-Bologna), M. Pilia
(INAF/OA-Cagliari), F. Longo (Univ. Trieste, and INFN Trieste)

report on behalf of the AGILE Team:

AGILE observed the long GRB 190829A at T0 = 2019-08-29 19:55:53 (UT) first
reported by Fermi GBM (GCN 25551) and by Swift (GCN 25552).

A sub-threshold gamma-ray source (at about 2.5 sigma) was found by
integrating the AGILE-GRID data from T0 to T0 + 100 s.

The following preliminary GRID values of 3-sigma upper limits (ULs) are
obtained above 50 MeV:

- 5.5e-08 erg cm^-2 s^-1 over the time interval (T0; T0 + 100 s);
- 1.9e-09 erg cm^-2 s^-1 over the time interval (T0; T0 + 5 hr).

These measurements were obtained with AGILE observing a large portion of
the sky in spinning mode. Additional analysis of AGILE data is in progress.


GRB_name: GRB190829A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25579
SUBJECT: GRB 190829A, Swift-BAT refined analysis
DATE:    19/08/30 15:10:52 GMT
FROM:    Hans Krimm at NSF/NASA-GSFC  <hkrimm@nsf.gov>

A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), S. Dichiara (NASA/GSFC/UMCP),
H. A. Krimm (NSF), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
(i.e. the Swift-BAT team):(i.e. the Swift-BAT team):

Using the data set from T-239 to T+963 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 190829A (trigger #922968)
(Dichiara, et al., GCN Circ. 25552).  The BAT ground-calculated position is
RA, Dec = 44.542, -8.958 deg which is 
  RA(J2000)  =  02h 58m 10.0s 
  Dec(J2000) = -08d 57' 28.4" 
with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 5%.

The mask-weighted light curve shows an early peak centered at T-50 sec, coincident 
with the Fermi/GBM trigger (Lesage, et al., GCN Circ. 25575).  This early peak 
shows more counts in the higher energy bands (> 50 keV) than is typical for a precursor.  
This was followed by the main peak of emission from T-5 to T+10 sec, peaking at the 
trigger time.  Finally, there was a weak, hard peak between T+15 and T+20 sec.  
T90 (15-350 keV) is 58.2 +- 8.9 sec (estimated error including systematics).

The time-averaged spectrum from T-51.9 to T+7.2 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.56 +- 0.21.  The fluence in the 15-150 keV band is 6.4 +- 0.7 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T-0.01 sec in the 15-150 keV band
is 18.0 +- 2.7 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/922968/BA/


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25580
SUBJECT: GRB 190829A: KAIT Detection of the Optical Afterglow
DATE:    19/08/30 17:48:47 GMT
FROM:    Weikang Zheng at UC Berkeley  <weikang@berkeley.edu>

WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on
behalf of the KAIT GRB team:

The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, observed the Swift GRB 190829A (Dichiara et al.,
GCN 25552) starting at 0.604 days after the burst. Observations
were performed with a total of 8 images in clear (roughly R) filters
with exposure time of 60 s per image. We detected the optical
afterglow (Xu et al., GCN 25555; Lipunov et al., GCN 25558
Kumar et al., GCN 25560; Heintz et al., GCN 25563; Valeev et al.,
GCN 25565; Chen et al., GCN 25569; Oates et al., GCN 25570; Lipunov
et al., GCN 25573) in our co-added images and we estimate the
clear band magnitude to be ~19.0 without applying galaxy subtraction.


GRB_name: GRB190829A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25581
SUBJECT: GRB 190829A: Follow up VLA and VLBI radio observations urged
DATE:    19/08/30 20:21:02 GMT
FROM:    Arnon Dar at Technion-Israel Inst. of Tech  <arnon@physics.technion.ac.il>

S. Dado and A. Dar report,

The long duration, low luminosity GRB190829A [1] at redshift z=0.0785 [2] 
with Ep=130 +/- 20 keV and Eiso~1.8E50 erg, most probably, is an ordinary 
narrowly beamed GRB being viewed from far off-axis -it satisfies well the 
correlation (1+z)Ep propto (Eiso)^{1/3}, predicted [3] by the cannonball 
model of GRBs, as can be seen from figure 3 of [4].  Like in SHB 170817A
[5], VLA and VLBI follow up observations of the radio afterglow of
GRB190829A may resolve its compact superluminal source and measure its 
apparent superluminal velocity, Vapp ~ 2c/theta, from which  its far 
off-axis viewing angle theta  can be determined [6]. We urge such follow 
up VLA and VLBI radio observations of its afterglow.

[1] S. Lesage et al.,  GCN 25575.
[2] A. F. Valeev et al., GCN  25565.
[3] A. Dar & A. De R'ujula, arXiv:astro-ph/0012227 (Eq. 40).
[4] S. Dado & A. Dar, arxiv:1908.05116.
[5] K. P. Mooley, et al., Nature, 561, 355 (2018) [arXiv:1806.09693].
[6] A. Dar & A. De R'ujula, arXiv:astro-ph/0008474.


GRB_name: GRB190829A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25582
SUBJECT: GRB 190829A: No Neutrino Counterpart detected with ANTARES
DATE:    19/08/30 20:49:41 GMT
FROM:    Antoine Kouchner at ANTARES Collaboration  <kouchner@apc.in2p3.fr>

Alexis Coleiro (APC/Univ de Paris) and Damien Dornic (CPPM/CNRS) report on behalf of the ANTARES Collaboration:

Using data from the ANTARES detector, we have performed a follow-up analysis of the recently reported GRB 190829A (Fermi-GBM GCN 25551, Swift GCN 25552) also observed in TeV gamma-rays ( H.E.S.S GCN 25566). 

No up-going muon neutrino candidate events were detected within 3 degrees of the GRB coordinates during a +/- 1h time-window centered on the time of the Swift Burst Alert, and over which the potential source remained visible all time. A search over an extended time window of +1 day has also yielded no detection (55% visibility). 
 
This leads to a preliminary 90% confidence level upper limit on the muon-neutrino radiant fluence from a point source of about 15 GeV.cm^-2 over the energy range 3 TeV â€“ 3 PeV (the range corresponding to 5-95% of the detectable flux) for an E^-2 power-law spectrum, and about 30 GeV.cm^-2 (500 GeV - 250 TeV) for an E^-2.5 spectrum, computed for the time of the Swift Burst Alert. 
 
ANTARES is the largest undersea neutrino detector (Mediterranean Sea) and it is primarily sensitive to astrophysical neutrinos in the TeV-PeV energy range. At 10 TeV, the median angular resolution for muon neutrinos is about 0.5 degrees. In the range 1-100 TeV ANTARES has a competitive sensitivity to this position in the sky.


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25583
SUBJECT: GRB 190829A: MMT detection of the optical afterglow
DATE:    19/08/30 23:41:32 GMT
FROM:    Wen-fai Fong at Northwestern U  <wfong@northwestern.edu>

W. Fong (Northwestern), T. Laskar (U. Bath), G. Schroeder, D. Coppejans and R. Margutti (Northwestern) report:

"We observed the location of the GRB 190829A (Fermi Collab. et al., GCN 25551; Dichiara et al., GCN 25552) with the MMTCam mounted on the MMT 6.5-meter telescope on Mount Hopkins, Arizona. We obtained 15x60-sec each in g- and r-bands at a mid-time of 2019 August 30.493 UT (15.89 hr post-burst). The observations have a mean airmass of 1.03, 1.0" seeing, and were taken in thin, variable clouds. We detect the optical afterglow (Xu et al., GCN 25555; Lipunov et al., GCN 25558; Kumar et al., GCN 25560; Heintz et al., GCN 25563; Valeev et al., GCN 25565; Chen et al., GCN 25569; Oates et al., GCN 25570; Zheng & Filippenko, GCN 25580) with a preliminary magnitude of r~20.0 +/- 0.1 AB mag, not corrected for Galactic extinction and calibrated to Pan-STARRS1. Our measurement is considerably fainter than the KAIT measurement at a similar epoch (Zheng & Filippenko, GCN 25580), likely attributable to the difference in filter, and substantial but uncertain host galaxy contribution.

Compared to earlier r-band observations of the afterglow at dt > 1.3 hr, we measure an optical flux decline rate of F~t^-1.3. This is consistent with the measured Swift/XRT afterglow decline rate on these timescales (https://www.swift.ac.uk/xrt_live_cat/00922968/).

Further observations are planned. We thank the MMT staff, and in particular ShiAnne Kattner and Nelson Caldwell, for their assistance with planning and executing these observations."


GRB_name: GRB190829A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25584
SUBJECT: GRB 190829A: UKIRT detection of the NIR Afterglow
DATE:    19/08/31 00:49:09 GMT
FROM:    Gregory SungHak Paek at SNU  <shpaek@astro.snu.ac.kr>

Gregory S. H. Paek and Myungshin Im (CEOU/SNU), on behalf of a larger
collaboration

We observed the afterglow of GRB 190829A (Fermi GBM Team, GCN 25551;
Dichiara et al., GCN 25552) with the United Kingdom Infrared Telescope
(UKIRT). The observation started at 2019-08-30 12:30:51.984 UT or about 16
hours after the event.

The afterglow is clearly detected in all J, H and K bands, and preliminary
magnitudes are derived from quick-look data, using nearby 2MASS stars as
photometry references.

Filter Date UT-start AB_mag

K    2019-08-30 12:30:51.984    16.95 +/- 0.21

H    2019-08-30 12:38:40.013    17.53 +/- 0.08

J    2019-08-30 12:46:27.005    18.09 +/- 0.05

This shows an J-,H-, and K-band fading of 0.75, 0.85, and 0.55 mag with
respect to the value reported by Chen et al. (GCN 25569).

Further observations are planned.

We thank the staffs at UKIRT for carrying out the observation.

[GCN OPS NOTE(05sep19):  Per author's request, the referenced
Circular in the first line was changed from "2555" to "25551".]


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25585
SUBJECT: GRB 190829A: Liverpool Telescope optical photometry
DATE:    19/08/31 03:50:09 GMT
FROM:    Daniel Perley at Liverpool JMU  <d.a.perley@ljmu.ac.uk>

D. A. Perley and A. M. Cockeram (LJMU) report:

We obtained observations of the afterglow of GRB 190829A (Dichiara et 
al., GCN 25552; Lesage et al., GCN 25575; Xu et al., GCN 25555) with the 
IO:O imager on the 2m robotic Liverpool Telescope.  Two epochs of 
imaging in the u, g, r, i, and z filters were acquired on 2019-08-30 UT 
(at approximately 03:33 and 05:01) plus one epoch of g, r, in and z 
imaging on 2019-08-31 UT (starting at 02:27).  The afterglow is clearly 
detected in griz in all three epochs.  It is not detected in u-band.

For our most recent epoch, we report the following magnitudes after 
subtraction of the presumptive host galaxy using PS1 catalog images 
(times relative to the Swift trigger, in days):

  t-t0    filt   mag       unc
  ------  ----   -----     ----
  1.2715    i  = 20.75 +/- 0.10
  1.2809    g  = 22.45 +/- 0.21
  1.2903    r  = 21.65 +/- 0.10
  1.2996    z  = 19.88 +/- 0.06

Further observations are planned.










DisclaimerNone


GRB_name: GRB190831A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25586
SUBJECT: GRB 190831A: Fermi GBM Final Real-time Localization
DATE:    19/08/31 08:07:51 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 07:57:31 UT on 31 Aug 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190831A (trigger 588931056.191116 / 190831332).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 65.6, Dec = 14.9 (J2000 degrees, equivalent to J2000 04h 22m, 14d 54'), with a statistical uncertainty of 5.0 degrees.

The angle from the Fermi LAT boresight is 99.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190831332/quicklook/glg_skymap_all_bn190831332.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190831332/quicklook/glg_healpix_all_bn190831332.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190831332/quicklook/glg_lc_medres34_bn190831332.gif


GRB_name: GRB190829A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25589
SUBJECT: GRB 190829A: NOEMA detection of the mm afterglow
DATE:    19/08/31 15:01:35 GMT
FROM:    Alexander Kann at IAA-CSIC  <kann@iaa.es>

A. de Ugarte Postigo (HETH/IAA-CSIC and DARK/NBI), M. Bremer (IRAM), D. 
A. Kann (HETH/IAA-CSIC), S. Schulze (Weizmann), C. C. Thoene, M. Blazek, 
K. Bensch, J. F. Agui (all HETH/IAA-CSIC), L. Izzo (DARK/NBI), D. A. 
Perley (LJMU), S. Martin (ALMA), I. de Gregorio-Monsalvo (ESO), M. 
Michalowski (AOI-AMU), D. B. Malesani (DARK/NBI, DAWN/NBI) R. 
Sanchez-Ramirez (INAF-IAPS) report:

We observed the afterglow of GRB 190829A (Fermi GBM team, GCN #25551; 
Dichiara et al., GCN #25552), at a redshift of z = 0.0785 (Valeev et al. 
GCN #25565) with NOEMA at 90 GHz. Observations started at 01:26 UT on 31 
August, 29.48 hrs after the GRB. The afterglow is well detected and had 
a flux density of 6.3 mJy at 90 GHz.

We derive the following refined coordinates for the afterglow:

RA. (J2000): 02:58:10.510
Dec (J2000): -08:57:28.44

with an error of +/- 0".1.


GRB_name: GRB190829A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25591
SUBJECT: GRB 190829A: TNG imaging of the NIR afterglow
DATE:    19/08/31 17:53:09 GMT
FROM:    Paolo D'Avanzo at INAF-OAB  <pda.davanzo@gmail.com>

P. D'Avanzo (INAF-OAB), V. D'Elia (ASI/SSDC), A. Rossi (INAF-OAS), A. Melandri (INAF-OAB), M. De Pasquale (Istanbul University), 
D. B. Malesani (DTU space), G. Andreuzzi, A. Garcia de Gurtubai Escudero (INAF/TNG), I. Carleo (Wesleyan University) report on 
behalf of the CIBO collaboration:


We observed the afterglow of GRB 190829A (Dichiara et al., GCN 25552; Lesage et al., GCN 25575; Xu et al., GCN 25555) 
with the 3.6m Italian TNG telescope (Canary Islands, Spain), equipped with the NICS infrared camera in imaging mode. 

We obtained a series of images with the J, H and Ks filters on 2019 Aug 31 from 03:45 to 05:52 UT (i.e. from about 
31.8 hours to about 34 hours after the GRB). 

From preliminary aperture photometry, the NIR afterglow is clearly detected with the following magnitudes: 

J  = 18.8 +/- 0.2 
H  = 18.1 +/- 0.1 
Ks = 17.8 +/- 0.1

(AB, calibrated against the 2MASS catalogue). We cannot exclude contamination from the host galaxy light. 

Compared to the magnitudes reported by Paek & Im (GCN 25584), our results are consistent with a power-law decay with 
index alpha ~ 1 of the NIR afterglow flux. 


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25592
SUBJECT: GRB 190829A: Liverpool Telescope observations
DATE:    19/08/31 21:01:12 GMT
FROM:    Martin Blazek at HETH/IAA-CSIC  <alf@iaa.es>

M. Blazek, L. Izzo. D. A. Kann (all HETH/IAA-CSIC), A. de Ugarte-Postigo
(HETH/IAA-CSIC, DARK/NBI) and C. C. Thoene (HETH/IAA-CSIC) report:

We observed the  GRB 190829A (Fermi GBM team, GCN 25551; Dichiara et al.,
GCN 25552) with the 2-m Liverpool Telescope located in La Palma, Spain.
The observation started at 05:29:50 UT on August 30, 2019 (t-t0 = 9.55 hours).
We obtained 5x60 seconds exposures in r'. We clearly detected the optical
afterglow inside the SWIFT error circle given of Evans et al. (GCN 25567).
We measure the following magnitude

r' = 19.79 +- 0.10 mag,

Magnitudes were derived from against comparison stars from the SDSS catalogue
and are in the AB system.


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25595
SUBJECT: GRB 190829A: Keck LRIS spectroscopy of the optical afterglow
DATE:    19/08/31 21:28:59 GMT
FROM:    Kishalay De at Caltech, GROWTH  <kde@astro.caltech.edu>

K. De (Caltech), V. Karambelkar (Caltech), M. M. Kasliwal (Caltech)
report on behalf of the GROWTH collaboration

We obtained a spectrum of the optical afterglow (GCN #25555, #25558,
#25560) of GRB190829A (GCN #25551, #25552) with the Low Resolution
Imaging Spectrometer (LRIS; Oke et al. 1995) on the Keck I telescope.
Observations began at UT 2019-08-31 03:35 for a total exposure time of
20 minutes. The afterglow is clearly detected in the data, and
exhibits a featureless red continuum. Narrow galaxy emission lines of
H alpha and [S II]  are detected at a redshift of z = 0.078,
consistent with the redshift of the underlying galaxy. The red
continuum and host emission features are consistent with those
reported in GCN #25563 and #25565.


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25597
SUBJECT: GRB 190829A: Continued fading inferred from Liverpool Telescope photometry
DATE:    19/09/01 14:36:35 GMT
FROM:    Daniel Perley at Liverpool JMU  <d.a.perley@ljmu.ac.uk>

D. A. Perley and A. M. Cockeram (LJMU) report:

We obtained additional observations of the afterglow of GRB 190829A 
(Dichiara et al., GCN 25552; Lesage et al., GCN 25575; Xu et al., GCN 
25555) with the IO:O imager on the 2m robotic Liverpool Telescope.  A 
single epoch consisting of two 150s exposures in both i and z bands was 
acquired on 2019-09-01 between 04:11 and 04:22 (UT).  The afterglow has 
faded significantly since our previous observation (GCN 25585).

We report the following magnitudes after subtraction of the presumptive 
host galaxy using PS1 catalog images (times relative to the Swift 
trigger, in days):

   t-t0    filt   mag       unc
   ------  ----   -----     ----
   2.3438  i    = 21.60 +/- 0.12
   2.3478  z    = 20.99 +/- 0.20

We infer a decay index (t^-alpha) of approximately 1.3.









DisclaimerNone


GRB_name: GRB190901A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25601
SUBJECT: GRB 190901A: Fermi GBM Final Real-time Localization
DATE:    19/09/01 21:31:54 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 21:21:49 UT on 1 Sep 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190901A (trigger 589065714.612092 / 190901890).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 220.3, Dec = 0.9 (J2000 degrees, equivalent to J2000 14h 41m, 0d 54'), with a statistical uncertainty of 1.0 degrees.

The angle from the Fermi LAT boresight is 85.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190901890/quicklook/glg_skymap_all_bn190901890.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190901890/quicklook/glg_healpix_all_bn190901890.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190901890/quicklook/glg_lc_medres34_bn190901890.gif


GRB_name: GRB190901A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25602
SUBJECT: GRB 190901A: BALROG localization (Fermi Trigger 589065714 / GRB 190901890)
DATE:    19/09/01 21:51:54 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

B. Biltzinger, F. Kunzweiler, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
589065714 at 21:21:49 on 01 Sept. 2019 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 224.7+/-0.8 deg
Decl.(2000.0) = -0.5+/-1.1 deg
We estimate an additional systematic error of 2 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB190901890/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB190901890/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB190901890/json

                        


GRB_name: GRB190831B
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25615
SUBJECT: GRB 190831B: CALET Gamma-Ray Burst Monitor detection of a short burst
DATE:    19/09/02 14:28:43 GMT
FROM:    Valentin Pal'shin at AGU  <val@phys.aoyama.ac.jp>

T. Tamura (Kanagawa U),
A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
Y. Asaoka, S. Ozawa, S. Torii (Waseda U), Y. Shimizu (Kanagawa U),
N. Cannady (GSFC/UMBC), M. L. Cherry (LSU),
S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

At 06:30:28.620 UTC on 31 August 2019, the CALET Gamma-ray Burst Monitor
(CGBM) triggered on short GRB 190831B. The burst signal was mainly seen by
the SGM detector.
No real-time CGBM GCN notice was distributed about this trigger
because the real-time communication from the ISS was off (loss of signal).

This short burst also triggered INTEGRAL SPI-ACS (trigger #8366).

The burst light curve shows a single pulse which starts at T-0.6 sec,
peaks at T-0.4 sec and ends at T+0.2 sec. The T90 and T50 durations
measured by the SGM data are 0.7 +- 0.2 sec and 0.4 +- 0.2 sec
(40-1000 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1251268076/

The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at the Waseda University.


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25623
SUBJECT: GRB 190829A: Flattening of optical light curve from continued Liverpool Telescope photometry
DATE:    19/09/03 05:28:44 GMT
FROM:    Daniel Perley at Liverpool JMU  <d.a.perley@ljmu.ac.uk>

D. A. Perley and A. M. Cockeram (LJMU) report:

We obtained further observations of the afterglow of GRB 190829A 
(Dichiara et al., GCN 25552; Lesage et al., GCN 25575; Xu et al., GCN 
25555) with the IO:O imager on the 2m robotic Liverpool Telescope. 
Observations were conducted on 2019-09-02 (03:33-04:03 UT) and 
2019-09-03 (02:46-03:36 UT).

In all three filters, the optical afterglow has slowed its decay from 
its previous power-law decline (GCN 25597), with little additional 
evolution in flux over the past 48 hours.  There is tentative evidence 
for rebrightening in the i-band.  We interpret this as the beginning of 
the rise of an associated supernova, but this still requires 
spectroscopic confirmation.

Additional i-band photometry (all subtracted versus PS1 reference 
imaging, with times in days referenced to the Swift trigger) is as follows:

  t-t0    filt   mag       unc
  ------  ----   -----     ----
  3.3193  i    = 21.69 +/- 0.12
  4.2889  i    = 21.45 +/- 0.12












DisclaimerNone


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25627
SUBJECT: GRB 190829A: Detection of radio afterglow with the uGMRT
DATE:    19/09/03 10:59:37 GMT
FROM:    Poonam Chandra at TIFR  <poonam@ncra.tifr.res.in>

Poonam Chandra (NCRA-TIFR) reports on behalf of a larger collaboration:

We observed GRB 190829A (GCN # 25551, 25552) with the upgraded Giant Metrewave Radio Telescope (uGMRT) in band 5 (1050â€”1450 MHz) on 2019 Sep 02.11 UT. In our preliminary analysis of the software backend data, we detect a radio afterglow with the flux density of 800+/-55 uJy at the optical afterglow position of the GRB (GCN # 25558). 

We thank the staff of the uGMRT that made these observations possible. uGMRT is run by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research. More observations are planned.


GRB_name: GRB190903A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25633
SUBJECT: GRB 190903A: Fermi GBM Final Real-time Localization
DATE:    19/09/03 17:29:59 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 17:19:36 UT on 3 Sep 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190903A (trigger 589223981.255486 / 190903722).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 62.4, Dec = -64.9 (J2000 degrees, equivalent to J2000 04h 09m, -64d 54'), with a statistical uncertainty of 6.3 degrees.

The angle from the Fermi LAT boresight is 86.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190903722/quicklook/glg_skymap_all_bn190903722.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190903722/quicklook/glg_healpix_all_bn190903722.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190903722/quicklook/glg_lc_medres34_bn190903722.gif


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25635
SUBJECT: GRB 190829A: MeerKAT radio observation
DATE:    19/09/03 22:19:25 GMT
FROM:    Alexander van der Horst at George Washington U  <ajvanderhorst@gwu.edu>

I. Monageng (UCT/SAAO), A.J. van der Horst (GWU), P.A. Woudt (UCT)
and M. Bottcher (NWU) report on behalf of a large collaboration:

"We observed the position of the GRB 190829A afterglow at 1.3 GHz with
the MeerKAT radio telescope on September 2, from 2:00 to 3:19 UT, i.e.
3.3 days after the burst (GCN 25551, 25552).
We detect a radio source with a flux density of 842 +/- 42 microJy at
the position of the optical counterpart (GCN 25552, 25555).

We would like to thank the staff at the South African Radio Astronomy
Observatory for scheduling and obtaining these DDT observations.â€


GRB_name: GRB190903A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25636
SUBJECT: GRB 190903A: Fermi GBM detection
DATE:    19/09/03 23:22:28 GMT
FROM:    Bagrat Mailyan at UAH  <bm0054@uah.edu>

B. Mailyan (UAH) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 17:19:36.26 UT on 3 September 2019, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 190903A (trigger 589223981/190903722).

The on-ground calculated location, using the GBM trigger
data, is RA = 62.43 , DEC = -64.86  (J2000 degrees,
equivalent to 11h 32m, -17d 46'), with an uncertainty
of 6.3 degrees (radius, 1-sigma containment).

The angle from the Fermi LAT boresight is 86  degrees.

The GBM light curve consists of a single short spike
with a duration (T90) of about 0.27s (50-300 keV).
The time-averaged spectrum from T0-0.064s to T0+0.128s is
adequately fit by a Band function with Epeak = 824 +/- 308 keV,
alpha = -0.79 +/- 0.13, and beta = -2.15 +/- 0.36

The event fluence (10-1000 keV) in this time interval is
 (7.8 +/- 0.65)E-07 erg/cm^2. The 1-sec peak photon flux measured
starting from T0-0.38s in the 10-1000 keV band is 3.01 +/- 0.23 ph/s/cm^2."

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html
For Fermi GBM data and info,
please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25641
SUBJECT: GRB 190829A: LCO Optical Afterglow Detection
DATE:    19/09/04 02:39:09 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:


We observed Fermi GRB 190829A (Fermi GBM Team at MSFC/Fermi-GBM, GCN 25551) with
the LCO 1-m Sinistro instrument on August 30, from 00:21 to 00:44 UT
(corresponding to 4.43 to 4.81 hours from the GRB trigger time)
with the SDSS i' filter.

We performed a series of 10x120s exposures, and we clearly
detect the optical afterglow (Xu et al. GCN 25555) with
the following  magnitude:

i' = 15.92 +/- 0.09

This flux measurement may be partially contaminated by the host galaxy, and it is calibrated against several USNO-B1.0 objects near the GRB location but is not corrected for Galactic Extinction.

Observations and analysis are ongoing with data from a second epoch collected on August 31, and a planned follow-up on September 3.

These observations were possible thanks to the USVI NASA-EPSCoR Research Infrastructure Development (RID) grant NNX16AL44A.


GRB_name: GRB190904A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25642
SUBJECT: GRB 190904A: Fermi GBM Final Real-time Localization
DATE:    19/09/04 04:21:19 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 04:11:00 UT on 4 Sep 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190904A (trigger 589263065.737252 / 190904174).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 35.9, Dec = -25.0 (J2000 degrees, equivalent to J2000 02h 23m, -25d 00'), with a statistical uncertainty of 12.7 degrees.

The angle from the Fermi LAT boresight is 98.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190904174/quicklook/glg_skymap_all_bn190904174.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190904174/quicklook/glg_healpix_all_bn190904174.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190904174/quicklook/glg_lc_medres34_bn190904174.gif


GRB_name: GRB190901A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25646
SUBJECT: GRB 190901A: Insight-HXMT/HE detection
DATE:    19/09/04 06:48:31 GMT
FROM:    Ce Cai at IHEP  <caice@ihep.ac.cn>

J. M. Yao, Y. G. Zheng, C. Cai, Q. Luo, S. Xiao, Q. B. Yi, 
Y. Huang, C. K. Li, G. Li, X. B. Li, J. Y. Liao, S. L. Xiong,
C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, A. M. Zhang, 
Y. F. Zhang, X. F. Lu, C. L. Zou (IHEP), Y. J. Jin, 
Z. Zhang (THU), T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, 
M. Wu, Y. P. Xu, S. N. Zhang (IHEP), 
report on behalf of the Insight-HXMT team:

At 2019-09-01T21:21:57.80 (T0), Insight-HXMT/HE detected 
GRB 190901A (trigger ID: HEB190901890) in a routine search of the data, 
which was also triggered by Fermi GBM (GCN #25601).

The Insight-HXMT/HE light curve mainly consists of a single  
pulse with a duration (T90) of 15.69 s measured from T0-3.00 s. 
The 1-ms peak rate, measured from T0+0.95 s, is 1500 cnts/sec. 
The total counts from this burst is 12538 counts. 
URL_LC: http://www.hxmt.org/images/GRB/HEB190901890_lc.jpg 

All measurements above are made with the CsI detectors operating in the 
regular mode with the energy range of about 80-800 keV (deposited energy). 
Only gamma-rays with energy greater than about 200 keV can penetrate 
the spacecraft and leave signals in the CsI detectors installed inside 
of the telescope. 

Insight-HXMT is the first Chinese space X-ray telescope, which was 
funded jointly by the China National Space Administration (CNSA) and 
the Chinese Academy of Sciences (CAS). 
More information about it could be found at: 
http://www.hxmt.org.


GRB_name: GRB190829A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25651
SUBJECT: GRB190829A: GROND detection of the accompanying SN
DATE:    19/09/04 10:14:13 GMT
FROM:    Jan Bolmer at MPE/Garching  <jan@bolmer.de>

J. Bolmer, J. Greiner, and T.-W. Chen (all MPE) report

We have been using GROND (Greiner et al. 2008, PASP 120, 405) to follow up the
afterglow of GRB 190829A (Dichiara et al., GCN 25552) at z=0.08 (Valeev et al.,
GCN 25565).
The light of the optical transient has been fading in all GROND bands during the first 
days, was then flattening and is now finally showing a relativley sharp rise in all seven
GROND bands (e.g. about 0.5 mag in z' to 19.55 +/- 0.03 mag_AB; 330s integration
time) between 4.5 and 5.5 days
after the BAT trigger. This behavior can be interpreted as the 
upcoming supernova component.

Further spectroscopic follow up is encouraged.


GRB_name: GRB190829A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25652
SUBJECT: GRB 190829A: MASTER confirmation of GROND SN
DATE:    19/09/04 11:34:56 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, F.Balakin,  E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa,A.Kuznetsov, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik,
T.Pogrosheva,  D.Kuvshinov(Lomonosov Moscow State University, SAI, Physics Department),
R. Podesta, C.Lopez, F. Podesta, C.Francile(Observatorio Astronomico Felix Aguilar OAFA),
H.Levato(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),
R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias),
D. Buckley(South African Astronomical Observatory),
O.A. Gres, N.M. Budnev, O.Ershova(Irkutsk State University, API),
A. Tlatov, D. Dormidontov(Kislovodsk Solar Station of the Pulkovo Observatory),
V. Yurkov, A. Gabovich, Yu. Sergienko(Blagoveschensk Educational State University)

MASTER-SAAO robotic telescope
(http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy,
vol.2010, 30L)
observed GRB 190829A (Fermi GCN 25551, Swift GCN25552) every night since 
discovery OT (Xu et al., GCN 25555; Lipunov et al., GCN 25553; Kumar et 
al., GCN 25560; Heintz et al., GCN 25563; Valeev et al., GCN 25565).

We also see the appearance OT (Bolmer et al., GCN 25651)  in place
MASTER OT 025810.51-085727.2

RA, Dec = 02h 58m  10.51s  -08d 57m 27.2s 
(Lipunov et al., GCN 25558)

at 2019-09-04 02:56:18 with 
mlim=20.5 .
SN unfiltered magnitude ~19.5.

This message can be cited.


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25657
SUBJECT: GRB 190829A: Liverpool Telescope observations of a slow supernova rise
DATE:    19/09/04 16:36:59 GMT
FROM:    Daniel Perley at Liverpool JMU  <d.a.perley@ljmu.ac.uk>

D. A. Perley and A. M. Cockeram (LJMU) report:

We obtained another epoch of r/i/z imaging of the optical counterpart of 
GRB 190829A (Dichiara et al., GCN 25552; Lesage et al., GCN 25575; Xu et 
al., GCN 25555) with IO:O on the Liverpool Telescope Telescope on 
2019-09-04 between 04:43 and 05:32 UT.  Image subtraction was performed 
using PS1 imaging as a template.  We report the following photometry:

  t-t0    filt   mag        unc
  ------  ----   -----     ----
  5.3707  i      21.32 +/- 0.09
  5.3941  z      20.61 +/- 0.10

This is consistent with a continued, slight rise compared to our 
previous two LT epochs (e.g., i = 21.45 at t = 4.29 days; GCN 25623) and 
with our earlier interpretation of the light curve flattening as the 
appearance of an associated supernova.  Spectroscopic confirmation is 
still necessary to solidify this interpretation.

We note that our z-band measurement is 1 magnitude fainter than that 
reported by Bolmer et al. (GCN 25651) at a similar epoch, and we do not 
confirm the sharp, short-timescale rise that they report.  It is 
possible that the difference arises due to lack of host galaxy 
subtraction in the GROND photometry.













DisclaimerNone


GRB_name: GRB190829A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25660
SUBJECT: Konus-Wind observation of GRB 190829A
DATE:    19/09/04 17:16:45 GMT
FROM:    Anastasia Tsvetkova at Ioffe Institute  <tsvetkova@mail.ioffe.ru>

A. Tsvetkova, S. Golenetskii, R.Aptekar, D. Frederiks,
M. Ulanov, D. Svinkin, A. Lysenko, A. Kozlova and T. Cline
on behalf of the Konus-Wind team, report:

The long GRB 190829A which triggered Swift/BAT
at T0=T0(BAT)=19:56:44.60 UT
(Swift/BAT detection: Dichiara et al., GCN 25552; Lien et al., GCN 25579;
Fermi GBM detection: Lesage et al., GCN 25575)
was detected by Konus-Wind in the waiting mode.

The burst light curve shows two emission episodes:
the first pulse lasts from ~T0-51.6 s to ~T0-42.8 s,
and the second pulse lasts from ~T0-4.5 s to ~T0+10.2 s.
The total duration of the burst is ~61.8 s.

As observed by Konus-Wind, the burst had a fluence of
1.29(-0.13,-0.15)x10^-5 erg/cm2 and a 2.944-s peak flux,
measured from ~T0(BAT)-1.58 s, of 1.13(-0.11,+0.13)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

Fitting the K-W 3-channel time-integrated spectrum
(from ~T0(BAT)-51.628 s to ~T0(BAT)+10.196 s)
in the 20 keV - 2 MeV range
by a simple power law model yields
the PL index = 2.30(-0.08,+0.09),
chi2 = 0.61 / 1 dof.

Modelling the K-W 3-channel spectrum of the initial pulse
(from ~T0(BAT)-51.628 s to ~T0(BAT)-48.684 s)
in the 20 keV - 2 MeV range
by a power law with exponential cutoff model
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) yields
alpha = -1.33(-0.23,+0.30),
and Ep =579(-281,+2282) keV.

Assuming the redshift z=0.0785
(Valeev  et al., GCN 25565; De et al., GCN Circ. 25595)
and a standard cosmology model with H_0 = 67.3 km/s/Mpc,
Omega_M = 0.315, and Omega_Lambda = 0.685 (Planck Collaboration, 2014),
we estimate the following rest-frame parameters:
the isotropic energy release E_iso is ~2.0x10^50 erg,
the peak luminosity L_iso is ~1.9x10^49 erg/s,
and the rest-frame peak energy of the initial pulse spectrum,
Ep,z, is ~624 keV.

All the quoted errors are estimated at the 1 sigma confidence level.
All the presented results are preliminary.

The K-W light curve of this burst is available at
http://www.ioffe.rssi.ru/LEA/GRBs/GRB190829A/


GRB_name: GRB190903A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25662
SUBJECT: IPN triangulation of GRB 190903A (short)
DATE:    19/09/04 22:48:35 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, A. Kozlova,
and T. Cline on behalf of the Konus-Wind team,

K. Hurley, on behalf of the IPN,

A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
on behalf of the Fermi GBM team,

and

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,
report:

The short-duration GRB 190903A
(Fermi-GBM detection: Fermi GBM Team, GCN Circ. 25633;
Mailyan and Meegan, GCN Circ. 25636)
was detected by Fermi (GBM trigger 589223981), INTEGRAL (SPI-ACS),
and Konus-Wind, at about 62376 s UT (17:19:36).

We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
    63.950 (04h 15m 48s) -59.485 (-59d 29' 04")
  Corners:
    62.459 (04h 09m 50s) -49.304 (-49d 18' 15")
    66.042 (04h 24m 10s) -66.310 (-66d 18' 34")
    64.926 (04h 19m 42s) -65.995 (-65d 59' 43")
    61.374 (04h 05m 30s) -46.559 (-46d 33' 33")
  ---------------------------------------------
The error box area is about 7.5 sq. deg, and its maximum
dimension is 19.9 deg (the minimum one is 27.5 arcmin).
The Sun distance was 100 deg.

This box may be improved.

The IPN localization is consistent with, but reduces the area of, the 
Fermi-GBM one.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB190903_T62377/IPN/

The Konus-Wind time history and spectrum will be given in a forthcoming
GCN Circular.


GRB_name: GRB190829A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25664
SUBJECT: GRB190829A: Keck LRIS spectroscopic confirmation of the accompanying supernova
DATE:    19/09/05 03:11:38 GMT
FROM:    Giacomo Terreran at Northwestern/CIERA  <giacomo.terreran@northwestern.edu>

G. Terreran, W. Fong, R. Margutti, A. Miller, K. Alexander, P. Blanchard, D. Coppejans, K. Paterson (Northwestern) report:

We observed the optical afterglow of GRB 190829A (Fermi Collab. et al., GCN 25551; Dichiara et al., GCN 25552) with the Low Resolution Imaging Spectrometer (LRIS) mounted on the 10-m Keck I telescope at a mid-time of 14:15 UT on 2019 Sep 4 (5.76 days after the Swift trigger). We obtained 3x1200-s of spectroscopy covering a wavelength range of ~3200-10200 Ang.

The spectrum appears very red and shows features consistent with a broad-line SN one week before maximum light. In particular, a very broad and shallow feature is present at 7800 Ang, possibly associated with O I. We find the best match to be with SN 2006aj a few days post explosion. However, a reddening correction with E(B-V) of ~0.6-0.9 mag is necessary to match the slope of the continuum of SN 2006aj at these phases. The high reddening inferred from the optical spectrum is consistent with the relatively high absorption column density reported by J.P. Osborne et al. (GCN 25568) in their X-ray analysis.

The emergence of the supernova light is consistent with the reported photometric flattening (J. Bolmer et al., GCN 25651; V. Lipunov et al., GCN 25652) and re-brightening (D. A. Perley and A. M. Cockeram; GCN 25657) of the optical source.

----------------------------------------------
Giacomo Terreran
Postdoctoral Associate
Northwestern University
----------------------------------------------


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25667
SUBJECT: GRB 190829A optical observation
DATE:    19/09/05 17:14:04 GMT
FROM:    Roberto Nesci at INAF/IAPS-Roma Italy  <roberto.nesci@inaf.it>

A. Vagnozzi (Stroncone Observatory), R. Nesci (INAF/IAPS-Roma)

The GRB 190829A (Dichiara et al. GCN Circ 25552) was observed at Stroncone 
Observatory (MPC 589) with the 50cm R-C telescope, a CCD SBIG camera
and the I_Cousins filter. Nine frames with 300s exposure each were
obtained: Bias, Flat and Dark current corrections were applied with IRAF
standard tasks.
Aperture photometry was performed with IRAF/apphot. The contribution
from the underlying galaxy was subtracted assuming a symmetric light
distribution, and evaluated about 0.2 mag. Comparison stars were taken
from PanSTARRS-DR1 (i') and GSC2.3.2 (N) with very consistent results
besides the zero point offset.
Mid-exposure time was 2019-08-30T00:47:15 UT; the magnitude of the GRB
was I_C=16.7 corrected for the galaxy contribution but not for reddening.


GRB_name: GRB180620A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25671
SUBJECT: GRB 180620A: SEDM Observations
DATE:    19/09/05 22:46:33 GMT
FROM:    Virginia Cunningham at U of MD  <vcunning@astro.umd.edu>

V. Cunningham (U of Maryland), J. D. Neill (Caltech), S. B. Cenko

(NASA GSFC), and R. Walters (Caltech) report on behalf of the

SEDM team:


We observed the optical counterpart to GRB 180620A (Evans, et al.,

GCN 22798)  with the Spectral Energy Distribution Machine (SEDM)

on the 60 inch telescope at Palomar Observatory. The SEDM is a

low resolution (R ~ 100) integral field unit spectrometer with a multi-

band (ugri) rainbow camera imager (see Blagorodnova et al. 2018,

PASP, 130, 035003, and Rigault et al. 2019, A&A, 627, A115).


The SEDM began observing the optical counterpart at 9:37:37 UTC

(63 minutes after the burst trigger time). We performed 2 x 1200 s

exposures over the wavelength range 3800-9200 A. The continuum

emission is well-fit by a power law spectrum with index alpha = 1.4

(f_nu ~ nu^-alpha). We do not confidently identify any obvious

emission or absorption features in the spectrum.


GRB_name: GRB190905A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25672
SUBJECT: GRB 190905A: Fermi GBM Final Real-time Localization
DATE:    19/09/05 23:48:54 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 23:38:28 UT on 5 Sep 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190905A (trigger 589419513.488626 / 190905985).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 234.5, Dec = 3.1 (J2000 degrees, equivalent to J2000 15h 37m, 3d 06'), with a statistical uncertainty of 3.6 degrees.

The angle from the Fermi LAT boresight is 97.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190905985/quicklook/glg_skymap_all_bn190905985.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190905985/quicklook/glg_healpix_all_bn190905985.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190905985/quicklook/glg_lc_medres34_bn190905985.gif


GRB_name: GRB190829A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25676
SUBJECT: GRB 190829A: ATCA cm-band detection
DATE:    19/09/06 13:54:36 GMT
FROM:    Tanmoy Laskar at U of Bath  <tanmoylaskar@gmail.com>

T. Laskar (Bath), S. Bhandari (CSIRO), G. Schroeder, W. Fong, K. D.
Alexander (Northwestern), E. Berger (Harvard), R. Chornock (Ohio U.), D.
Coppejans, R. Margutti (Northwestern), E. Ayache, C. G. Mundell, P. Schady,
and H. J. van Eerten (Bath), report on behalf of a larger collaboration:

"We observed GRB 190829A (Fermi GBM team, GCN 25551; Dichiara et al, GCN
25552) with the Australia Telescope Compact Array beginning at 2019 Aug 30
16:10 UT, 20.2 hours after the burst. We detect the cm-band afterglow at
the position of the mm-band counterpart (de Ugarte Postigo et al., GCN
25589) with a preliminary flux density of ~ 2 mJy at 5.5 GHz.

Further observations are on-going.

We thank the CSIRO staff for rapidly scheduling these observations. The
Australia Telescope Compact Array is part of the Australia Telescope
National Facility which is funded by the Australian Government for
operation as a National Facility managed by CSIRO."


GRB_name: GRB190829A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25677
SUBJECT: GRB 190829A: GTC confirmation of an associated Type Ic-BL Supernova
DATE:    19/09/06 14:47:37 GMT
FROM:    Alexander Kann at IAA-CSIC  <kann@iaa.es>

A. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), L. Izzo (DARK/NBI), C. C 
Thoene, M. Blazek, K. Bensch, J. F. Agui, D. A. Kann (all 
HETH/IAA-CSIC), A. L. Cabrera Lavers, N. Castro-Rodriguez (both IAC, 
Grantecan), and A. Tejero Caro (Grantecan) report:

We obtained spectroscopy of GRB 190829A (Fermi GBM team, GCN #25551; 
Dichiara et al., GCN #25552) with OSIRIS on the 10.4 m Gran Telescopio 
Canarias on La Palma, Spain, based on Director's Discretionary Time 
proposal GTC02-19BDDT. We obtained 3 x 600 s exposures each in two 
grisms, R1000B and R1000R, yielding a total wavelength coverage from 
3700 to 10000 AA. Observations began at 03:57 UT on 06 September 2019, 
7.35 days after the trigger.

After correcting for the large amount of host-galaxy reddening, using 
A_V = 1.5 mag and an SMC-like extinction curve, we find a spectrum 
showing broad undulations. An excellent match is obtained vs. an 
X-shooter spectrum of SN 2010bh at a similar epoch (Bufano et al., ApJ, 
753, 67), especially above 5000 AA (see 
https://www.iaa.csic.es/~deugarte/GRBs/190829A/GRB190829A_SN.png). We 
further find a good match to a spectrum of SN 1998bw (Patat et al. 2001, 
ApJ, 555, 900) taken 6.6 days before peak light (and ~ 8 days post-GRB), 
but a less good match for SN 2006aj at a similar time after the GRB.

We find evidence for broad absorption lines of SiII 6355, OI 7775, and 
CaII 8490, with the expansion speed of SiII being ~ 30,000 km/s, very 
similar to SN 1998bw at this time after trigger. This fully confirms the 
results of Terreran et al. (GCN #25664) that this rising source (Perley & Cockerma, 
GCN 25623, Bolmer et al., GCN 25651) is indeed the SN accompanying GRB 
190829A, and we unambiguously identify it as a broad-lined Type Ic SN 
similar to other SNe accompanying GRBs.

Comparison spectra were obtained from WISeREP 
(https://wiserep.weizmann.ac.il, Yaron & Gal-Yam, 2012, PASP, 124, 66.)

[GCN OPS NOTE(07sep19): Per author's request, "(GCN #25664)" was added
in the 4th paragraph.]


GRB_name: GRB190906A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25678
SUBJECT: IPN triangulation of GRB 190906A (short)
DATE:    19/09/06 17:35:09 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

K. Hurley, on behalf of the IPN,

I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin,
on behalf of the HEND-Odyssey GRB team,

D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, A. Kozlova,
and T. Cline on behalf of the Konus-Wind team,

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,

S. Barthelmy, J. Cummings, H. Krimm, and D. Palmer,
on behalf of the Swift-BAT team, and

W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr,
on behalf of the GRS-Odyssey GRB team, report:

The short-duration GRB 190906A has been detected by
Konus-Wind, INTEGRAL (SPI-ACS), Mars-Odyssey (HEND)
and Swift (BAT), at about 3889 s UT (01:04:49).
The burst was outside the coded field of view of the BAT.

We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
   267.576 (17h 50m 18s) -11.916 (-11d 54' 59")
  Corners:
   267.903 (17h 51m 37s)  -9.219 ( -9d 13' 08")
   267.589 (17h 50m 21s) -11.207 (-11d 12' 24")
   267.230 (17h 48m 55s) -15.208 (-15d 12' 30")
   267.563 (17h 50m 15s) -12.659 (-12d 39' 34")
  ---------------------------------------------
The error box area is about 1463 sq. arcmin, and its maximum
dimension is 6.0 deg (the minimum one is 6.6 arcmin).
The Sun distance was about 103 deg.

This box may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB190906_T03893/IPN

The Konus-Wind time history and spectrum will be given in a forthcoming
GCN Circular.


GRB_name: GRB190906B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25679
SUBJECT: GRB 190906B: Fermi GBM Final Real-time Localization
DATE:    19/09/06 18:35:26 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 18:25:09 UT on 6 Sep 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190906B (trigger 589487114.28841 / 190906767).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 171.8, Dec = -71.6 (J2000 degrees, equivalent to J2000 11h 27m, -71d 35'), with a statistical uncertainty of 3.5 degrees.

The angle from the Fermi LAT boresight is 74.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190906767/quicklook/glg_skymap_all_bn190906767.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190906767/quicklook/glg_healpix_all_bn190906767.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190906767/quicklook/glg_lc_medres34_bn190906767.gif


GRB_name: GRB190823A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25680
SUBJECT: GRB 190823A: Swift-XRT afterglow detection
DATE:    19/09/06 19:19:49 GMT
FROM:    Elena Ambrosi at INAF-IASF  <elena.ambrosi@inaf.it>

V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAB), A.
Tohuvavohu (U Toronto), J.A. Kennea (PSU), B. Sbarufatti (PSU), A.P.
Beardmore (U. Leicester), J.P. Osborne (U. Leicester) and P.A. Evans
(U. Leicester) report on behalf of the Swift-XRT team:

Swift-XRT has performed further observations of the MAXI-detected burst
GRB 190823A (Iwakiri et al. GCN Circ. 25456).
The observations now extend from T0+12.3 ks and T0+1148.9 ks with a 
total exposure time of 4.1 ks in Photon Counting (PC) mode.

The source previously reported by Ambrosi et al. (GCN Circ. 25476) is
fading with 3-sigma significance, and is therefore likely the GRB
afterglow.
Using 147 s of PC mode data and 1 UVOT image, we find an enhanced XRT
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 279.68735, -43.52789 which is
equivalent to:

RA (J2000): 18h 38m 44.97s
Dec(J2000): -43d 31' 40.4"

with an uncertainty of 8.7 arcsec (radius, 90% confidence). This
position is 18.6 arcmin from the MAXI position.  The source is fading
with alpha >0.7.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00020932.
The results of the full analysis of the tiled XRT observations are
available at https://www.swift.ac.uk/xrt_products/TILED_GRB00085.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB190829A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25682
SUBJECT: GRB 190829A observations in CrAO, photometry of the SN
DATE:    19/09/07 10:59:13 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

A. Volnova (IKI), V. Rumyantsev (CrAO),  A. Pozanenko (IKI), S. Belkin 
(IKI), E. Mazaeva (IKI) report on behalf of IKI GRB FuN collaboration:

We are observing the optical afterglow (Xu et al., GCN 25555;  Lipunov 
et al., GCN 25558; Kumar et al. GCNC 25560) of GRB 190829A (Fermi team, 
GCN 25551; Dichiara et al., GCN 25552) at 0.0785 (Valeev et al., GCN 
25565). Observations of the OA with ZTSh 2.6m telescope of CrAO started 
on Aug. 30 and continued up to Sep. 6 in B and R filters.

Using masked subtraction we can compare the brightness of the OA in 
different epochs. The OA is steady fading between Aug. 30 and Sep. 2. 
Between the two epochs (2019-09-02T00:46:30 and 2019-09-06T00:40:50)  we 
clearly observe brightening of the OA (by 1.8 magnitude in R-filter) 
which corresponds to the rising Supernova (Bolmer et al., GCN 25651; 
Perley et al., GCN 25657; Terreran et al., GCN 25664; de Ugarte Postigo 
et al., GCN 25677).


GRB_name: GRB190901A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25687
SUBJECT: GRB 190901A: AstroSat CZTI detection
DATE:    19/09/09 11:17:45 GMT
FROM:    Ramkrishna Gaikwad at IUCAA/AstroSat  <ramkrishna@iucaa.in>

R. Gaikwad, V. Sharma and D. Bhattacharya (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data showed the detection of a GRB 190901A, which was also detected by Fermi GBM Final Real-time Localization (GCN #25601), BALROG localization (Biltzinger B. et al., GCN #25602), Global MASTER-Net (Lipunov V. et al., GCN #25603), Insight-HXMT/HE (Yao J. M. et al., GCN # 25646).

The source was clearly detected in the 40-200 keV energy range. The light curve shows multiple pulses of emission with the strongest peak at 2019-09-01 21:21:49.0 UT. The measured peak count rate associated with the burst is 215 cts/s above the background in the combined data of four quadrants, with a total of 891 cts. The local mean background count rate was 572 cts/s. Using cumulative rates, we measure a T90 of 13.4 s.

It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.

CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.


GRB_name: GRB190910A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25692
SUBJECT: GRB 190910A: Fermi GBM Final Real-time Localization
DATE:    19/09/10 00:49:51 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 00:39:37 UT on 10 Sep 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190910A (trigger 589768782.860244 / 190910028).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 229.5, Dec = 9.1 (J2000 degrees, equivalent to J2000 15h 18m, 9d 05'), with a statistical uncertainty of 6.6 degrees.

The angle from the Fermi LAT boresight is 61.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190910028/quicklook/glg_skymap_all_bn190910028.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190910028/quicklook/glg_healpix_all_bn190910028.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190910028/quicklook/glg_lc_medres34_bn190910028.gif


GRB_name: GRB190913A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25736
SUBJECT: GRB 190913A: Fermi GBM Final Real-time Localization
DATE:    19/09/13 03:53:25 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 03:43:09 UT on 13 Sep 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190913A (trigger 590038994.332068 / 190913155).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 264.4, Dec = 18.4 (J2000 degrees, equivalent to J2000 17h 37m, 18d 23'), with a statistical uncertainty of 19.9 degrees.

The angle from the Fermi LAT boresight is 73.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190913155/quicklook/glg_skymap_all_bn190913155.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190913155/quicklook/glg_healpix_all_bn190913155.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190913155/quicklook/glg_lc_medres34_bn190913155.gif


GRB_name: GRB190828C
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25745
SUBJECT: GRB 190828C: AstroSat CZTI detection
DATE:    19/09/14 06:46:33 GMT
FROM:    Ramkrishna Gaikwad at IUCAA/AstroSat  <ramkrishna@iucaa.in>

R. Gaikwad, V. Sharma and D. Bhattacharya (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data showed the detection of a GRB 190828C, which was also detected by Fermi GBM Final Real-time Localization (GCN #25519), BALROG localization (Burgess J. et al., GCN #25520).

The source was clearly detected in the 40-200 keV energy range. The light curve shows multiple pulses of emission with the strongest peak at 2019-08-28 14:44:26.0 UT. The measured peak count rate associated with the burst is 436 cts/s above the background in the combined data of four quadrants, with a total of 3237 cts. The local mean background count rate was 674 cts/s. Using cumulative rates, we measure a T90 of 11 s.

It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.

CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.

[GCN OPS NOTE(14sep19), Per author's GCN Circ. 25746, the GRB name in the SUBJECT-line has been changed
from "190928C" to "190828C".]


GRB_name: GRB190828C
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25746
SUBJECT: Correction in name: GRB 190828C (not GRB 190928C) : AstroSat CZTI detection
DATE:    19/09/14 06:56:48 GMT
FROM:    Ramkrishna Gaikwad at IUCAA/AstroSat  <ramkrishna@iucaa.in>

R. Gaikwad (IUCAA) report on behalf of the AstroSat CZTI team:

The GRB name of GRB 190828C (R. Gaikwad et al. GCN Circ. #25745) should be GRB 190828C.
I sincerely apologize for any confusion caused.


GRB_name: GRB190914A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25747
SUBJECT: GRB 190914A: Fermi GBM Final Real-time Localization
DATE:    19/09/14 08:26:59 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 08:16:34 UT on 14 Sep 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190914A (trigger 590141799.630546 / 190914345).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 18.4, Dec = 21.5 (J2000 degrees, equivalent to J2000 01h 13m, 21d 30'), with a statistical uncertainty of 14.9 degrees.

The angle from the Fermi LAT boresight is 54.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190914345/quicklook/glg_skymap_all_bn190914345.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190914345/quicklook/glg_healpix_all_bn190914345.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190914345/quicklook/glg_lc_medres34_bn190914345.gif


GRB_name: GRB190915A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25750
SUBJECT: GRB 190915A: Fermi GBM Final Real-time Localization
DATE:    19/09/15 05:56:10 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 05:44:57 UT on 15 Sep 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190915A (trigger 590219102.911008 / 190915240).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 48.3, Dec = 4.0 (J2000 degrees, equivalent to J2000 03h 13m, 4d 00'), with a statistical uncertainty of 4.3 degrees.

The angle from the Fermi LAT boresight is 75.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190915240/quicklook/glg_skymap_all_bn190915240.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190915240/quicklook/glg_healpix_all_bn190915240.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190915240/quicklook/glg_lc_medres34_bn190915240.gif


GRB_name: GRB190915A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25751
SUBJECT: GRB 190915A: BALROG localization (Fermi Trigger 590219102 / GRB 190915240)
DATE:    19/09/15 06:11:07 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

F. Kunzweiler, B. Biltzinger, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
590219102 at 05:44:57 on 15 Sept. 2019 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 54.2+/-4.5 deg
Decl.(2000.0) = 7.2+/-3.1 deg
We estimate an additional systematic error of 1 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB190915240/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB190915240/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB190915240/json

                        


GRB_name: GRB190915A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25759
SUBJECT: GRB190915A: MASTER optical observation of BALROG Fermi GRB localization
DATE:    19/09/16 07:41:38 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, E. Gorbovskoy, V.Kornilov, F.Balakin, N.Tyurina,P.Balanutsa,A.Kuznetsov, 
V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov,V.Senik, T.Pogrosheva, K.Pozdnyakov,
A.Chasovnikov, V.Topolev, D.Kuvshinov(Lomonosov Moscow State University, SAI, Physics Department),
R. Podesta, C.Lopez, F. Podesta, C.Francile(Observatorio Astronomico Felix Aguilar OAFA),
H.Levato(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),
R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias),
D. Buckley(South African Astronomical Observatory),
O.A. Gres, N.M. Budnev, O.Ershova(Irkutsk State University, API),
A. Tlatov, D. Dormidontov(Kislovodsk Solar Station of the Pulkovo Observatory),
V. Yurkov, A. Gabovich, Yu. Sergienko(Blagoveschensk Educational State University)

MASTER Global Robotic Net (http://observ.pereplet.ru, Lipunov et al., 2010,Advances in Astronomy, vol.2010, 30L)
started inspect of Fermi  GRB190916A (GBM team GCN 25750, Trig.N 590219102, Ttrig=05:44:57 UT on 15 Sep 2019 )
BALROG localization (Kunzweiler et al. GCN 25751, R.A.,Dec(2000)=54.2+/-4.5 , 7.2+/-3.1 )
12 sec after notice time at MASTER-IAC, MASTER-OAFA, MASTER-SAAO.

MASTER-IAC robotic telescope located in Spain (IAC Teide Observatory)
started inspect of the FERMI GRB 190915A BALROG localization 12 sec after notice time 
(1594 sec after trigger time) at 2019-09-15 06:11:31 UT, with upper limit up to  17.6 mag.
Observations started at twilight.  The observations began at zenit distance = 26 deg. The sun  altitude  is -8.8 deg.

MASTER-OAFA robotic telescope  located in Argentina (OAFA observatory of San Juan National University)
started inspect of the FERMI GRB 190915A BALROG localization 25 sec after  notice time (1607 sec after trigger time)
  at 2019-09-15 06:11:44 UT, with upper limit up to  17.7 mag.
The observations began at zenit distance = 52 deg. The sun  altitude  is -53.4 deg.

MASTER-SAAO robotic telescope  located in South Africa (South African 
Astronomical Observatory) started inspect of the Fermi GRB 190915A BALROG localization 
at 2019-09-15 21:31:37 UT, with upper limit up to  18.9 mag. The observations 
began at zenit distance = 77 deg. The sun  altitude  is -57.5 deg.

The galactic latitude b = -60 deg., longitude l = 98 deg.

Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/event.php?id=1136619

The observation and reduction will be continued.
The message may be cited.


GRB_name: GRB190915A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25760
SUBJECT: GRB 190915A: Insight-HXMT/HE detection
DATE:    19/09/16 10:38:15 GMT
FROM:    YaoGuang Zheng at IHEP  <zhengyg@ihep.ac.cn>

Y. G. Zheng, C. Cai, Q. Luo, S. Xiao, Q. B. Yi, 
Y. Huang, C. K. Li, G. Li, X. B. Li, J. Y. Liao, S. L. Xiong,
C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, A. M. Zhang, 
Y. F. Zhang, X. F. Lu, C. L. Zou (IHEP), Y. J. Jin, 
Z. Zhang (THU), T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, 
M. Wu, Y. P. Xu, S. N. Zhang (IHEP), 
report on behalf of the Insight-HXMT team:

At 2019-09-15T05:44:58.40 (T0), Insight-HXMT/HE detected 
GRB 190915A (trigger ID: HEB190915239) in a routine search of the data, 
which was also triggered by Fermi/GBM (GCN #25750).

The Insight-HXMT/HE light curve mainly consists of a single  
pulse with a duration (T90) of 13.66 s measured from T0-1.75 s. 
The 1-ms peak rate, measured from T0-0.07 s, is 1427 cnts/sec. 
The total counts from this burst is 8974 counts. 
URL_LC: http://www.hxmt.org/images/GRB/HEB190915239_lc.jpg 

All measurements above are made with the CsI detectors operating in the 
regular mode with the energy range of about 80-800 keV (deposited energy). 
Only gamma-rays with energy greater than about 200 keV can penetrate 
the spacecraft and leave signals in the CsI detectors installed inside 
of the telescope. 

Insight-HXMT is the first Chinese space X-ray telescope, which was 
funded jointly by the China National Space Administration (CNSA) and 
the Chinese Academy of Sciences (CAS). 
More information about it could be found at: 
http://www.hxmt.org.


GRB_name: GRB190916A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25762
SUBJECT: GRB 190916A: Fermi GBM Final Real-time Localization
DATE:    19/09/16 14:20:33 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 14:10:14 UT on 16 Sep 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190916A (trigger 590335819.554478 / 190916590).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 321.3, Dec = -48.9 (J2000 degrees, equivalent to J2000 21h 25m, -48d 53'), with a statistical uncertainty of 11.8 degrees.

The angle from the Fermi LAT boresight is 117.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190916590/quicklook/glg_skymap_all_bn190916590.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190916590/quicklook/glg_healpix_all_bn190916590.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190916590/quicklook/glg_lc_medres34_bn190916590.gif


GRB_name: GRB190828B
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25771
SUBJECT: GRB 190828B: AstroSat CZTI detection
DATE:    19/09/17 09:06:06 GMT
FROM:    Ramkrishna Gaikwad at IUCAA/AstroSat  <ramkrishna@iucaa.in>

R. Gaikwad, V. Sharma, D. Bhattacharya and A. Vibhute (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data showed the detection of a GRB 190828B, which was also detected by Fermi GBM Final Real-time Localization (GCN #25516), Swift (S. Dichiara. et al., GCN # 25517), Swift-XRT (Beardmore A. et al., GCN # 25521), Swift-BAT (Krimm H. et al., GCN # 25534), Fermi GBM (Roberts J. et al., GCN # 25535),.

The source was clearly detected in the 40-200 keV energy range. The light curve shows multiple pulses of emission with the strongest peak at 2019-08-28 12:59:59.0 UT. The measured peak count rate associated with the burst is 297 cts/s above the background in the combined data of four quadrants, with a total of 3424 cts. The local mean background count rate was 611 cts/s. Using cumulative rates, we measure a T90 of 31.9 s.

It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.

CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.


GRB_name: GRB190919A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25783
SUBJECT: GRB 190919A: Fermi GBM Final Real-time Localization
DATE:    19/09/19 18:30:16 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 18:20:02 UT on 19 Sep 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190919A (trigger 590610007.65552 / 190919764).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 357.4, Dec = -21.8 (J2000 degrees, equivalent to J2000 23h 49m, -21d 48'), with a statistical uncertainty of 2.5 degrees.

The angle from the Fermi LAT boresight is 83.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190919764/quicklook/glg_skymap_all_bn190919764.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190919764/quicklook/glg_healpix_all_bn190919764.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190919764/quicklook/glg_lc_medres34_bn190919764.gif


GRB_name: GRB190919B
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25788
SUBJECT: GRB 190919B: A long GRB detected by INTEGRAL
DATE:    19/09/20 00:41:44 GMT
FROM:    Sandro Mereghetti at IASF-Milano/INAF  <sandro.mereghetti@inaf.it>

S.Mereghetti (INAF, IASF-Milano), D.Gotz (CEA, Saclay),  C.Ferrigno,
E.Bozzo, V.Savchenko (ISDC, Versoix), L.Ducci (IAAT, Germany and ISDC,
Versoix)
and J.Borkowski (CAMK, Torun) report:

a gamma ray burst lasting about 30 s has been detected by IBAS in the
IBIS/ISGRI data at 23:46:40  UT of September 19, 2019.

The refined coordinates (J2000) are:
R.A.=  311.8862 deg
DEC.=  -44.7029 deg
with an uncertainty of   1.5  arcmin (90% c.l.).

The burst had a peak flux of  0.6  ph/cm2/s (20-200 keV, 1-s integration
time) and a fluence in the same energy range of about  3e-7 erg/cm2.

A plot of the light curve will  be posted at
http://ibas.iasf-milano.inaf.it/IBAS_Results.html


GRB_name: GRB190919B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25789
SUBJECT: GRB 190919B: GROND detection of the NIR afterglow
DATE:    19/09/20 02:30:15 GMT
FROM:    Jan Bolmer at MPE/Garching  <jan@bolmer.de>

J. Bolmer (MPE Garching) report: 

We observed the field of GRB 190919B (INTEGRAL trigger 8377; Mereghetti et al. GCN 25788) 
simultaneously in g'r'i'z'JHKs with GROND (Greiner et al. 2008, PASP 120, 405) mounted
at the 2.2 m MPG telescope at ESO La Silla Observatory (Chile). 

Observations started at 23:50 UT on 19 September 2019, 3.6 min after the GRB trigger.
They were performed at an average seeing of 1.31" and at an average airmass of 1.2. We
detect the fading NIR afterglow at the following coordinates and with the following
preliminary AB magnitudes at 407 +/- 194 s after the trigger:

Ra, Dec = 311.87765 -44.69533

J = 16.33 +/- 0.05,
H = 16.06 +/- 0.05,
Ks = 15.92 +/- 0.07.

Given magnitudes are calibrated against 2MASS field stars and are not corrected
for the expected Galactic foreground extinction corresponding to a reddening of
E_(B-V)=0.10 mag in the direction of the burst (Schlafly & Finkbeiner 2011).


GRB_name: GRB190919B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25790
SUBJECT: GRB 190919B: Swift ToO observations
DATE:    19/09/20 07:01:17 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a ToO observation of the INTEGRAL GRB 190919B. 
Automated analysis of the XRT data will be presented online at
https://www.swift.ac.uk/ToO_GRBs/00020948

Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. These are
not necessarily related to the INTEGRAL event. Any X-ray source
considered to be a probable afterglow candidate will be reported via a 
GCN Circular after manual consideration.

Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).

This circular is an official product of the Swift-XRT team.


GRB_name: GRB190919B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25791
SUBJECT: GRB 190919B: MASTER OT early detection at GROND position
DATE:    19/09/20 07:30:40 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

N.Tyurina, V. Lipunov, E. Gorbovskoy, V.Kornilov, F.Balakin,
P.Balanutsa,A.Kuznetsov, V.Vladimirov, D. Vlasenko, I.Gorbunov,
D.Zimnukhov,V.Senik, T.Pogrosheva, K.Pozdnyakov,
A.Chasovnikov, V.Topolev, D.Kuvshinov(Lomonosov Moscow State University, SAI,
Physics Department),
R. Podesta, C.Lopez, F. Podesta, C.Francile(Observatorio Astronomico Felix
Aguilar OAFA),
H.Levato(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),
R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias),
D. Buckley(South African Astronomical Observatory),
O.A. Gres, N.M. Budnev, O.Ershova(Irkutsk State University, API),
A. Tlatov, D. Dormidontov(Kislovodsk Solar Station of the Pulkovo Observatory),
V. Yurkov, A. Gabovich, Yu. Sergienko(Blagoveschensk Educational State
University)


We see GRB190919B (INTEGRAL trigger 8377; Mereghetti et al. GCN 25788) at 
prompt and afterglow stage with flare (after 7 min)  on several MASTER 
telescopes (Lipunov et al., GCN 25787) at GROND position (Bolmer et al, 25789).

Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/event.php?id=1136619

The OT coordinates are:

  RA, Dec = 20h 47m 30.56s , -44d 41m 42s.5
Error = 0.3 arcsec


The observation and reduction will be continued.
The message may be cited.


GRB_name: GRB190919B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25792
SUBJECT: GRB 190919B: VLT/X-shooter redshift
DATE:    19/09/20 08:30:58 GMT
FROM:    Daniele B Malesani at DTU Space  <malesani@space.dtu.dk>

G. Pugliese (Univ. Amsterdam), L. Izzo (DARK/NBI), J. Bolmer (MPE 
Garching), N. R. Tanvir (Univ Leicester), D. B. Malesani (DTU Space), D. 
Xu (NAO/CAS), D. A. Kann (HETH/IAA-CSIC), J. P. U. Fynbo (DAWN/NBI), 
report on behalf of the Stargate collabaration:

We observed the optical afterglow (Bolmer, GCN 25789) of the INTEGRAL 
GRB 190919B (Mereghetti et al., GCN 25788) using the ESO VLT UT2 
(Kueyen) equipped with the X-shooter spectrograph. Our spectra cover the 
wavelength range 3000-24700 AA, and consist of 4 exposures by 600 s 
each. The observation mid time was 2019 Sep 20.194 UT (4.87 hr after the 
GRB).

In a 30 s image taken with the acquisition camera on Sep 20.1714 UT, we 
detect the optical afterglow, for which we measure a magnitude r = 20.10 
+- 0.02 AB (calibrated against nearby stars from the SkyMapper catalog; 
Wolf et al. 2018, PASA, 35, 010; https:doi.org/10.4225/41/593620ad5b574).

We clearly detect continuum over the full covered wavelength range. A 
wide trough is visible around 5130 AA, which we identify as due to H I. 
This is confirmed by the presence of the Ly alpha forest blueward of 
this wavelength. We also detect multiple, narrow absorption features 
across all the three arms, which we interpret as due to e.g. S II, Si 
II, O I, S IV, C IV, Fe II, Mg II, Ca I, at a common redshift z = 3.225.

We acknowledge excellent support from the ESO observing staff in 
Paranal, in particular Pedro Figueira, Nestor Jimenez, Camila Navarrete, 
and Juan Carlos Olivares.


GRB_name: GRB190919B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25793
SUBJECT: GRB 190919B: Swift-XRT observations
DATE:    19/09/20 14:05:48 GMT
FROM:    Andy Beardmore at U Leicester  <ab271@leicester.ac.uk>

A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAB), J.A. Kennea (PSU), B.
Sbarufatti (PSU), D.N. Burrows (PSU), J.P. Osborne (U. Leicester), K.L.
Page (U. Leicester), P. D'Avanzo (INAF-OAB) and P.A. Evans (U.
Leicester) report on behalf of the Swift-XRT team:

Swift-XRT has performed follow-up observations of the INTEGRAL-detected
burst GRB 190919B (Mereghetti et al. GCN Circ. 25788), collecting 3.0
ks of Photon Counting (PC) mode data between T0+28.6 ks and T0+36.4 ks.


An uncatalogued X-ray source has been detected 1.1 arcsec from the
reported GROND afterglow position (Bolmer, GCN Circ. 25789):

Source 1:
  RA (J2000):  311.87783  =  20:47:30.68
  Dec (J2000): -44.69542  =  -44:41:43.5
  Error: 2.1 arcsec (radius, 90% conf. [Enhanced position])
  Count-rate: 0.0222 [+0.0032, -0.0031] ct s^-1   
  Distance: 0 arcsec from INTEGRAL position.
  Flux: (7.16 [+1.03, -0.98])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)


The source is below the RASS limit and, due to the limited amount of
data available so far, shows no signs of fading.


The results of the XRT-team automatic analysis of the XRT observations,
including a position-specific upper limit calculator, are available at
https://www.swift.ac.uk/ToO_GRBs/00020948.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB190919B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25794
SUBJECT: GRB 190919B: FRAM-Auger optical detection
DATE:    19/09/20 15:00:30 GMT
FROM:    Martin Jelinek at Astro.Inst-AVCR,Ondrejov  <martin.jelinek@asu.cas.cz>

Martin Jelinek (ASU CAS Ondrejov, CZ), Sergey Karpov,
Martin Masek, Petr Janecek, Jakub Jurysek, Jan Ebr, Ronan Cunniffe,
Petr Travnicek, Michael Prouza (Institute of Physics, Prague, CZ)
and Jan Strobl (ASU CAS Ondrejov, CZ)

report:

The 30 cm robotic telescope FRAM-Auger in Malargue (Argentina)
reacted robotically to the INTEGRAL/IBAS alert of GRB190919B
(Mereghetti et al., GCNC 25788), starting with a series of 20 s
unfiltered images at 23:47:16 UT, i.e. 36 s post trigger.

We clearly detect the optical afterglow reported by Bolmer (GCN
25789), Tyurina et al. (GCN 25791) and Pugliese et al. (GCN
25792) at single frames. The optical lightcurve seems to have
a multi-peak structure with maxima reaching r'(AB) ~ 16.5 mag,
and fades beyond the single-image detection limit of r' ~ 17.2 by
~ 10 minutes post trigger. A detailed analysis is ongoing.


GRB_name: GRB190919B
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25795
SUBJECT: GRB 190919B: Swift/UVOT Upper Limits
DATE:    19/09/20 20:58:25 GMT
FROM:    Frank Marshall at Swift/UVOT  <marshall@milkyway.gsfc.nasa.gov>

F. E. Marshall (NASA/GSFC) and A. Beardmore (U. Leicester)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 190919B
28564 s after the INTEGRAL trigger (Mereghetti et al., GCN Circ. 25788).
No optical afterglow consistent with the optical position
(Bolmer, GCN Circ. 25789; Tyurina et al. GCN Circ. 25791)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

u_FC             28987        29196          206         >20.3
v                30258        36440          225         >19.6
b                29201        36022          301         >20.2
u                28987        35920          301         >20.7
w1               28564        35819          602         >20.8
m2               30471        30737          262         >20.3
w2               29416        36416         1204         >21.8

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.03 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB190919B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25796
SUBJECT: GRB 190919B: LCO Optical Afterglow Detection
DATE:    19/09/21 02:24:34 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:

We observed Fermi GRB 190919B (Mereghetti, GCN 25788) with
the LCO 1-m Sinistro instrument on September 20, from 17:58 to 19:10 UT
(corresponding to 18.27 to 19.47 hours from the GRB trigger time)
with the SDSS i and r filters.

We performed a series of 28x30s exposures in each band. We do not detect the source in individual frames; however we detect a source in stacked images (at least 5 stacked images) that is not present in USNO-B1.0 or 2MASS surveys with
the following  magnitudes:


i = 20.60 +/- 0.14

r = 21.48 +/- 0.18

This flux measurement may be partially contaminated by the host galaxy, and it is calibrated against several USNO-B1.0 objects near the GRB location but is not corrected for Galactic Extinction.

Analysis is ongoing to determine if the source is fading over the course of the observations, and therefore likely the GRB afterglow.

These observations were possible thanks to the USVI NASA-EPSCoR
Research Infrastructure Development (RID) grant NNX16AL44A.


GRB_name: GRB190919B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25798
SUBJECT: GRB 190919B: BOOTES-5/JGT and BOOTES-3/YA optical observations
DATE:    19/09/21 15:04:32 GMT
FROM:    Alberto J. Castro-Tirado at IAA-CSIC  <ajct@iaa.es>

Y.-D. Hu, E. Fernandez-Garcia and A. J. Castro-Tirado (IAA-CSIC), D. 
Hiriart and W. H. Lee (UNAM), S. Jeong and I. H. Park (SKKU) and M. D. 
Caballero-Garcia (ASU-CAS, CZ), I. Carrasco, C. Perez del Pulgar (Univ. 
de Malaga) and R. Querel (NIWA) on behalf of a larger collaboration, 
report:

The 60cm BOOTES-5/JGT robotic telescope at Observatorio Astronomico 
Nacional in San Pedro Martir (Mexico) automatically responded in 3.33 
hrs to the INTEGRAL trigger of GRB190919B (Mereghetti et al., GCNC 
25788). A series of unfiltered images were taken (60s exposure time). 
The optical source is detected at the position reported by Bolmer et al. 
(GCNC 25789) and Tyurina et al. (GCNC 25791) in the co-added image from 
which we derive a magnitude of 19.56 +/- 0.15 at median time of 4.41 h 
after the trigger.

Few hours later, the 60cm BOOTES-3/YA robotic telescope at NIWA Lauder 
in Otago (New Zealand) also automatically responded to this trigger and 
gathered a serie of unfiltered images (60s exposure time). The optical 
source still can be detected in the co-added image with a magnitude of f 
21.2 +/- 0.4 at a median time of 9.54 hrs after trigger.

These results confirm the fading of the afterglow. The magnitude is 
calibrated against the USNO-B1 catalog and is not corrected for Galactic 
extinction in the direction of the GRB. Further observations are 
ongoing.

We thank the staff at both the Observatorio Astronomico Nacional in San 
Pedro Martir and NIWA Lauder for their excellent support.


GRB_name: GRB190921A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25799
SUBJECT: GRB 190921A: Fermi GBM Final Real-time Localization
DATE:    19/09/21 16:56:12 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 16:45:55 UT on 21 Sep 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190921A (trigger 590777160.12475 / 190921699).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 338.4, Dec = -63.4 (J2000 degrees, equivalent to J2000 22h 33m, -63d 23'), with a statistical uncertainty of 5.4 degrees.

The angle from the Fermi LAT boresight is 17.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190921699/quicklook/glg_skymap_all_bn190921699.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190921699/quicklook/glg_healpix_all_bn190921699.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190921699/quicklook/glg_lc_medres34_bn190921699.gif


GRB_name: GRB190923A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25818
SUBJECT: GRB 190923A: Fermi GBM Final Real-time Localization
DATE:    19/09/23 14:58:21 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 14:48:02 UT on 23 Sep 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190923A (trigger 590942887.75117 / 190923617).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 8.2, Dec = -11.0 (J2000 degrees, equivalent to J2000 00h 32m, -11d 00'), with a statistical uncertainty of 4.9 degrees.

The angle from the Fermi LAT boresight is 43.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190923617/quicklook/glg_skymap_all_bn190923617.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190923617/quicklook/glg_healpix_all_bn190923617.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190923617/quicklook/glg_lc_medres34_bn190923617.gif


GRB_name: GRB190923A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25820
SUBJECT: GRB 190923A: BALROG localization (Fermi Trigger 590942887 / GRB 190923617)
DATE:    19/09/23 15:09:00 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

F. Kunzweiler, B. Biltzinger, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
590942887 at 14:48:02 on 23 Sept. 2019 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 5.9+/-1.6 deg
Decl.(2000.0) = -14.0+/-1.3 deg
We estimate an additional systematic error of 1 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB190923617/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB190923617/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB190923617/json

                        


GRB_name: GRB190926A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25848
SUBJECT: GRB 190926A: Swift detection of a burst
DATE:    19/09/26 10:06:20 GMT
FROM:    Hans Krimm at NSF/NASA-GSFC  <hkrimm@nsf.gov>

A. Melandri (INAF-OAB), M. G. Bernardini (INAF-OAB),
P. D'Avanzo (INAF-OAB), P. A. Evans (U Leicester), J.D. Gropp (PSU),
H. A. Krimm (NSF), A. Y. Lien (GSFC/UMBC), F. E. Marshall (NASA/GSFC)
and K. L. Page (U Leicester) report on behalf of the Neil Gehrels
Swift Observatory Team:

At 09:52:16 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 190926A (trigger=926515).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 100.599, +59.511 which is 
   RA(J2000) = 06h 42m 24s
   Dec(J2000) = +59d 30' 40"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  Since this is an image trigger, the BAT 
light curve showed no significant structure. 

The XRT began observing the field at 09:54:30.4 UT, 134.0 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 100.5699, 59.5292 which is equivalent to:
   RA(J2000)  = 06h 42m 16.78s
   Dec(J2000) = +59d 31' 45.1"
with an uncertainty of 4.8 arcseconds (radius, 90% containment). This
location is 84 arcseconds from the BAT onboard position, within the BAT
error circle. No event data are yet available to determine the column
density using X-ray spectroscopy. 

The initial flux in the 2.5 s image was 5.87e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 144 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers none of
the XRT error circle. The 8'x8' region for the list of sources generated
on-board covers 100% of the XRT error circle. The list of sources is typically
complete to about 18 mag. No correction has been made for the expected
extinction corresponding to E(B-V) of 0.06. 

Burst Advocate for this burst is A. Melandri (andrea.melandri AT brera.inaf.it). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB190926A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25850
SUBJECT: GRB 190926A: Enhanced Swift-XRT position
DATE:    19/09/26 19:43:25 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 3630 s of XRT Photon Counting mode data and 3 UVOT
images for GRB 190926A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 100.57044, +59.52920 which is equivalent
to:

RA (J2000): 06h 42m 16.90s
Dec (J2000): +59d 31' 45.1"

with an uncertainty of 2.0 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB190926A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25851
SUBJECT: GRB 190926A: Swift-XRT refined Analysis
DATE:    19/09/26 19:45:30 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

B. Sbarufatti (PSU), D.N. Burrows (PSU), J. D. Gropp (PSU), J.P.
Osborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U.
Leicester), P. D'Avanzo (INAF-OAB), M.G. Bernardini (INAF-OAB) and A.
Melandri report on behalf of the Swift-XRT team:

We have analysed 10 ks of XRT data for GRB 190926A (Melandri et al. GCN
Circ. 25848), from 140 s to 23.8 ks after the  BAT trigger. The data
comprise 685 s in Windowed Timing (WT) mode with the remainder in
Photon Counting (PC) mode. The enhanced XRT position for this burst was
given by Goad et al. (GCN Circ. 25850).

The late-time light curve (from T0+4.1 ks) can be modelled with an
initial power-law decay with an index of alpha=0.661 (+0.053, -0.030),
followed by a break at T+677 s to an alpha of 3.34 (+0.30, -0.12).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.804 (+/-0.023). The
best-fitting absorption column is  3.00 (+/-0.11) x 10^21 cm^-2, in
excess of the Galactic value of 7.5 x 10^20 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 4.1 x 10^-11 (5.5 x 10^-11) erg
cm^-2 count^-1. 

A summary of the WT-mode spectrum is thus:
Total column:      3.00 (+/-0.11) x 10^21 cm^-2
Galactic foreground: 7.5 x 10^20 cm^-2
Excess significance: 33.3 sigma
Photon index:      1.804 (+/-0.023)

If the light curve continues to decay with a power-law decay index of
3.34, the count rate at T+24 hours will be 3.2 x 10^-6 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.3 x
10^-16 (1.7 x 10^-16) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00926515.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB190926A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25852
SUBJECT: GRB 190926A: KAIT Optical Upper Limit
DATE:    19/09/26 20:22:19 GMT
FROM:    Weikang Zheng at UC Berkeley  <weikang@berkeley.edu>

WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on
behalf of the KAIT GRB team:

The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, responded to Swift GRB 190926A (Melandri et al.,
GCN 25848) starting at ~59 minutes after the burst. Observations
were performed in the clear (roughly R) filters, a total of 102
images were obtained and the exposure time was 60 s per image.
We do not detect any optical afterglow candidate within the Enhanced
XRT position error circle (Goad et al., GCN 25850), neither in single
image, nor in the co-add images. The typical limiting magnitude
of our single clear image is about 19.0 mag.


GRB_name: GRB190926A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25853
SUBJECT: GRB 190926A: Swift/UVOT Upper Limits
DATE:    19/09/26 20:47:53 GMT
FROM:    Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>

S. R. Oates (U.Warwick) and A. Melandri (INAF-OAB)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 190926A
144 s after the BAT trigger (Melandri et al., GCN Circ. 25848).
No optical afterglow consistent with the enhanced XRT position
(Goad et al. GCN Circ. 25850)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC           144          294          147         >20.2
u_FC               303          553          246         >19.3
white              144         6525          580         >20.9
v                  634        11670         1116         >20.0
b                  559         6321          432         >20.2
u                  303         6115          659         >20.0
w1                 685         5910          413         >19.8
m2                 659        12294         1022         >20.3
w2                 610        10756         1148         >20.6

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.06 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB190926A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25854
SUBJECT: GRB 190926A: MITSuME Akeno optical upper limits
DATE:    19/09/27 03:33:15 GMT
FROM:    Adachi Ryo at Tokyo Institute of Tech  <adachi@hp.phys.titech.ac.jp>

R. Adachi, K. L. Murata, M. Oeda, K.Shiraishi, K. Iida, M. Niwano,
F. Ogawa, R. Hosokawa, S. Toma, Y. Yatsu, and N. Kawai (TokyoTech)
report on behalf of the MITSuME collaboration:

We searched for the optical counterpart of GRB 190926A (A. Melandri et
al., GCN Circular #25848) with the optical three color (g', Rc, and
Ic) CCD cameras attached to the MITSuME 50 cm telescope of Akeno
Observatory, Yamanashi, Japan.
The observation started on 16:16:33 UT. We did not find any new point
sources within the XRT circle (M.R. Goad et al., GCN Circular #25850)
in all three bands.
We obtained the following 5-sigma limits for the magnitudes.

T0+[hour]   MID-UT    T-EXP[sec]    5-sigma limits
------------------------------------------------------------------------------------------------
 ~7.0         18:13:34    6960              g'>19.8, Rc>19.5, Ic>19.2
------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used UCAC4 catalog for flux calibration.
The magnitudes are expressed in the AB system.


GRB_name: GRB190926A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25856
SUBJECT: GRB 190926A: Upper Limit from OSN T150 Observation
DATE:    19/09/27 19:44:40 GMT
FROM:    Alexander Kann at IAA-CSIC  <kann@iaa.es>

D. A. Kann, M. Blazek (both HETH/IAA-CSIC), A. de Ugarte Postigo 
(HETH/IAA-CSIC, DARK/NBI), C. C. Thoene, K. Bensch, J. F. Agui (all 
HETH/IAA-CSIC), and A. Sota (IAA-CSIC) report:

We observed the field of GRB 190926A (Melandri et al. GCN #25848) with 
the 1.5m OSN telescope, at Sierra Nevada Observatory (Granada, Spain). 
The observation is centered 0.7321 days after the GRB and consisted of 
41 x 180 s exposures in the Ic band for a total exposure time of 7380 s.

No new object is detected within the refined XRT error circle (Goad et 
al. GCN #25850) down to a 3-sigma limit of Ic(AB) = 23.6 mag, as 
compared to stars of the PanSTARRS catalog. This is in agreement with 
other non-detections (Lipunov et al., GCN #25849, Zheng & Filippenko, 
GCN # 25852, Oates & Melandri, GCN #25853, Adachi et al., GCN #25854); 
and the very high-significance detection of excess hydrogen column 
density in the XRT observations (Sbarufatti et al., GCN #25851) 
indicates this is a dark GRB, and less likely a high-redshift one.


GRB_name: GRB190928A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25857
SUBJECT: Fermi  trigger No 591321287: Global MASTER-Net observations report 
DATE:    19/09/28 01:31:42 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, 
V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva, D.Kuvshinov 
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile 
(Observatorio Astronomico Felix Aguilar OAFA),

H.Levato 
(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),

R. Rebolo, M. Serra 
(The Instituto de Astrofisica de Canarias),

D. Buckley 
(South African Astronomical Observatory),

O.A. Gres, N.M. Budnev, O.Ershova 
(Irkutsk State University, API),

A. Tlatov, D. Dormidontov 
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich, Yu. Sergienko 
(Blagoveschensk Educational State University)




MASTER-SAAO robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB190928. (trigger No 591321287,06h 55m 16.080s , +53d 28m 58.80s, R=34.9) errorbox  2615 sec after notice time and 2694 sec after trigger time at 2019-09-28 00:39:36 UT, with upper limit up to  18.7 mag. The observations began at zenit distance = 79 deg. The sun  altitude  is -44.4 deg. 

The galactic latitude b = -60 deg., longitude l = 98 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1151511

We obtain a following upper limits.  

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

    2784 | 2019-09-28 00:39:36 |         MASTER-SAAO | (06h 35m 47.982s , +20d 03m 42.44s) |   C |   180 | 15.2 |        
    3242 | 2019-09-28 00:47:14 |         MASTER-SAAO | (06h 32m 29.819s , +22d 03m 41.37s) |   C |   180 | 17.6 |        
    3462 | 2019-09-28 00:50:54 |         MASTER-SAAO | (06h 44m 17.719s , +20d 04m 19.94s) |   C |   180 | 16.7 |        
    3764 | 2019-09-28 00:55:56 |         MASTER-SAAO | (06h 38m 18.849s , +24d 04m 10.15s) |   C |   180 | 17.1 |        
    3993 | 2019-09-28 00:59:45 |         MASTER-SAAO | (06h 32m 28.426s , +22d 03m 45.77s) |   C |   180 | 18.6 |        
    4450 | 2019-09-28 01:07:22 |         MASTER-SAAO | (06h 41m 32.555s , +22d 03m 59.98s) |   C |   180 | 18.4 |        
    4674 | 2019-09-28 01:11:05 |         MASTER-SAAO | (06h 44m 20.126s , +20d 04m 28.93s) |   C |   180 | 18.7 |        
    4890 | 2019-09-28 01:14:42 |         MASTER-SAAO | (06h 49m 44.878s , +22d 04m 15.98s) |   C |   180 | 18.5 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.


GRB_name: GRB190928A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25859
SUBJECT: GRB 190928A: AGILE/MCAL detection of a burst
DATE:    19/09/28 18:03:46 GMT
FROM:    Alessandro Ursi at INAF/IAPS  <alessandro.ursi@gmail.com>

A. Ursi (INAF/IAPS), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), M.
Cardillo, C. Casentini, G. Piano (INAF/IAPS), F. Lucarelli, C. Pittori, F.
Verrecchia (SSDC, and INAF/OAR), A. Bulgarelli, V. Fioretti, N. Parmiggiani
(INAF/OAS-Bologna), M. Pilia (INAF/OA-Cagliari), F. Longo (Univ. Trieste
and INFN Trieste), report on behalf of the AGILE Team:

AGILE detected a long burst at T0 = 2019-09-28 13:13:48.39 +/- 0.01 s
(UTC). The event is visible in the scientific ratemeters (RMs) of the
Super-AGILE (SA; 18-60 keV), Anti-Coincidence (AC; 50-200 keV), and
Mini-CALorimeter (MCAL; 0.4-100 MeV) detectors. Their light curves show a
multi-peaked profile, lasting ~20 s and releasing ~2,200 counts in the SA
RMs, lasting ~30 s and releasing ~160,000 counts in the AC RMs, and lasting
~20 s and releasing ~73,200 counts in the MCAL RMs. The ratemeters light
curves can be found at
http://www.agilescienceapp.it/notices/GRB_064516_496761236.785171_RM.png.

The event also triggered two Mini-Calorimeter (MCAL) data acquisitions (in
the 0.4-100 MeV energy range). Additional analysis of the AGILE data is in
progress.


GRB_name: GRB190926A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25860
SUBJECT: GRB 190926A: Swift-BAT refined analysis
DATE:    19/09/28 20:05:29 GMT
FROM:    Hans Krimm at NSF/NASA-GSFC  <hkrimm@nsf.gov>

C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), J. R. Cummings (CPI),
H. A. Krimm (NSF), A. Y. Lien (GSFC/UMBC), A. Melandri (INAF-OAB),
D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-239 to T+963 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 190926*A (trigger #926515)
(Melandri, et al., GCN Circ. 25848).  The BAT ground-calculated position is
RA, Dec = 100.616, 59.531 deg which is 
  RA(J2000)  =  06h 42m 27.9s 
  Dec(J2000) = +59d 31' 51.2" 
with an uncertainty of 2.3 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 50%.

The BAT mask-weighted light curve shows a complex structure with multiple
peaks extending from roughly T-120 sec to T+450 sec.  T90 (15-350 keV) is 
368.9 +- 20.9 sec (estimated error including systematics).

The time-averaged spectrum from T-0.00 to T+395.46 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.14 +- 0.18.  The fluence in the 15-150 keV band is 2.5 +- 0.2 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+52.95 sec in the 15-150 keV band
is 0.6 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/926515/BA/


GRB_name: GRB190926A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25862
SUBJECT: GRB 190926A: AbAO upper optical limit
DATE:    19/09/29 10:55:59 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

S. Belkin (IKI), A. Pozanenko (IKI), R. Ya. Inasaridze (AbAO, 
Samtskhe-Javakheti State University), E. Mazaeva (IKI), A. Volnova 
(IKI),  V. R. Ayvazian  (AbAO, Samtskhe-Javakheti State University), 
G.V.  Kapanadze (AbAO, Samtskhe-Javakheti State University), I. Molotov 
(KIAM) report on behalf of larger IKI GRB follow-up collaboration:

We observed  GRB 190926A (Melandri et al., GCN 25848) with AS-32 (0.7m) 
telescope of Abastumani Observatory starting on Sep. 27 (UT) 01:16:46. 
We obtained several 60 s exposures  in R-filter. We do not detect any 
source within enhanced Swift-XRT position (Goad et al., GCN 25850) in 
the stacked image. Photometry of the field  is following

Date       UT start t-T0    Filter Exp.  OT    Err. UL
                    (mid, days) (s)

2019-09-27 01:16:46 0.6493   R    21*60  n/d   n/d  20.8

Photometry is based on nearby USNO-B1.0 star (R2 magnitude):

USNO-B1.0_id R2
1496-0169403 18.52


The non detection in an agreement with previously reported results 
(Lipunov et al., GCN #25849, Zheng & Filippenko, GCN # 25852, Oates & 
Melandri, GCN #25853, Adachi et al., GCN #25854; Kann et al., GCN #25856).


GRB_name: GRB190928A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25864
SUBJECT: IPN triangulation of GRB 190928A (long/bright)
DATE:    19/09/29 19:07:00 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

K. Hurley, on behalf of the IPN,

I. G. Mitrofanov, D. Golovin, A. Kozyrev, M. L. Litvak,
and A. B. Sanin, on behalf of the HEND-Odyssey GRB team,

D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, A. Kozlova,
and T. Cline on behalf of the Konus-Wind team,

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,

and

W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr,
on behalf of the GRS-Odyssey GRB team, report:

The long-duration, very bright GRB 190928A
was detected by AGILE (Ursi et al., GCN Circ. 25859),
CALET (GBM trigger 1253711524), Konus-Wind, INTEGRAL (SPI-ACS),
and Mars-Odyssey (HEND) at about 47536 s UT (13:12:16).

We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
    36.579 (02h 26m 19s) +29.461 (+29d 27' 38")
  Corners:
    31.573 (02h 06m 17s) +35.236 (+35d 14' 10")
    40.668 (02h 42m 40s) +23.151 (+23d 09' 02")
    42.081 (02h 48m 19s) +19.298 (+19d 17' 54")
    32.689 (02h 10m 45s) +33.718 (+33d 43' 03")
  ---------------------------------------------
The error box area is about 4.56 sq. deg, and its maximum
dimension is 18.4 deg (the minimum one is 17.6 arcmin).
The Sun distance was about 139 deg.

This box may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB190928_T47536/IPN

The Konus-Wind time history and spectrum will be given in a forthcoming
GCN Circular.


GRB_name: GRB190928A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25865
SUBJECT: GRB 190928A: CALET Gamma-Ray Burst Monitor detection
DATE:    19/09/30 08:17:04 GMT
FROM:    Valentin Pal'shin at AGU  <val@phys.aoyama.ac.jp>

V. Pal'shin, A. Yoshida, T. Sakamoto, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
Y. Asaoka, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U),
N. Cannady (GSFC/UMBC), M. L. Cherry (LSU),
S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The long bright GRB 190928A (AGILE/MCAL detection: Ursi et al., GCN Circ.
25859; IPN triangulation: Hurley et al., GCN Circ. 25864) triggered the
CALET Gamma-ray Burst Monitor (CGBM) at 13:12:11.187 UTC on 28 September
2019. The burst signal was seen by all CGBM detectors.

The burst light curve shows two multi-peaked pulses separated by a period
of low-level emission. The first pulse starts at T+2.6 sec, peaks at
T+4.8 sec and ends at T+8.1 sec, the second, much brighter, pulse starts at
T+76.4 sec, peaks at T+106.1 sec and ends at T+175.5 sec.
The T90 and T50 durations measured by the SGM data are 106.6 +- 49.1 sec and
6.9 +- 0.4 sec (40-1000 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1253711524/

The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at the Waseda University.


GRB_name: GRB190930A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25866
SUBJECT: GRB 190930A: Fermi GBM Final Real-time Localization
DATE:    19/09/30 09:46:20 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 09:36:06 UT on 30 Sep 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190930A (trigger 591528971.501752 / 190930400).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 235.5, Dec = 3.9 (J2000 degrees, equivalent to J2000 15h 41m, 3d 53'), with a statistical uncertainty of 7.1 degrees.

The angle from the Fermi LAT boresight is 31.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190930400/quicklook/glg_skymap_all_bn190930400.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190930400/quicklook/glg_healpix_all_bn190930400.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190930400/quicklook/glg_lc_medres34_bn190930400.gif


GRB_name: GRB190928A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25867
SUBJECT: GRB 190928A: MASTER optical observations
DATE:    19/09/30 10:33:55 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tiurina, F.Balakin, P.Balanutsa,A.Kuznetsov, V.Vladimirov, D. Vlasenko, I.Gorbunov,
D.Zimnukhov,V.Senik, T.Pogrosheva, K.Pozdnyakov, A.Chasovnikov, V.Topolev, D.Kuvshinov(Lomonosov Moscow State University, SAI, Physics Department),
R. Podesta, C.Lopez, F. Podesta, C.Francile(Observatorio Astronomico Felix Aguilar OAFA),
H.Levato(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),
R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias),
D. Buckley(South African Astronomical Observatory),
O.A. Gres, N.M. Budnev, O.Ershova(Irkutsk State University, API),
A. Tlatov, D. Dormidontov(Kislovodsk Solar Station of the Pulkovo Observatory),
V. Yurkov, A. Gabovich, Yu. Sergienko(Blagoveschensk Educational State University)

MASTER Global Robotic Net (http://observ.pereplet.ru, Lipunov et al., 2010,Advances in Astronomy, vol.2010, 30L)
started inspect of long/bright (Hurley et al. IPN triangulation GCN 25864)
GRB 190928A (Ursi  et al. AGILE GCN 25859 , GCN 25865)

MASTER-SAAO robotic telescope located in South Africa (South African Astronomical Observatory)
  started inspect of the IPN GRB190928.55/GRB190928A errorbox  43353 sec after trigger time at 2019-09-29 01:14:49 UT,
with upper limit up to  19.8 mag.
The observations began at zenit distance = 54 deg. The sun  altitude is -38.1 deg.

MASTER-IAC robotic telescope  located in Spain (IAC Teide Observatory) 
started inspect of the IPN GRB190928.55 errorbox  50163 sec after trigger time at 2019-09-29 03:08:19 UT,
with upper limit up to  20.1 mag.
  The observations began at zenit distance =  4 deg. The sun  altitude  is -48.7 deg.

MASTER-Amur robotic telescope  located in Russia (Blagoveshchensk State Pedagogical University)
started inspect of the IPN GRB190928.55 errorbox  77575 sec after trigger time at 2019-09-29 10:45:11 UT,
with upper limit up to  17.2 mag.
Observations started at twilight.  The observations began at zenit distance = 67 deg. The sun  altitude  was -15.1 deg.

MASTER-Tunka robotic telescope  located in Russia (Applied Physics Institute, Irkutsk State University)
started inspect of the IPN GRB190928.55 errorbox  83489 sec after trigger time at 2019-09-29 12:23:45UT,
with upper limit up to  20.0 mag. Observations started at twilight. 
The observations began at zenit distance = 67 deg. The sun  altitude  is -15.2 deg.

MASTER-Kislovodsk robotic telescope  located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory)
started inspect of the IPN GRB190928.55 errorbox  1 days 18913 sec after trigger time at 2019-09-29 18:27:29 UT,
with upper limit up to  20.4 mag.
The observations began at zenit distance = 63 deg. The sun  altitude  is -36.9 deg.

The error-box center galactic latitude b = -60 deg., longitude l = 98 deg.

We obtained following upper limits.

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________
    43444 | 2019-09-29 01:14:49 |         MASTER-SAAO | (02h 47m 41.951s , +22d 01m 46.67s) |   C |   180 | 17.2 |
    43662 | 2019-09-29 01:18:27 |         MASTER-SAAO | (02h 32m 39.043s , +24d 01m 24.20s) |   C |   180 | 14.7 |
    50253 | 2019-09-29 03:08:19 |          MASTER-IAC | (02h 31m 38.751s , +23d 59m 41.60s) |   C |   180 | 19.9 |
    50254 | 2019-09-29 03:08:19 |          MASTER-IAC | (02h 40m 38.749s , +23d 55m 43.19s) |   C |   180 | 20.1 |
    51547 | 2019-09-29 03:29:52 |          MASTER-IAC | (02h 31m 36.457s , +23d 59m 19.80s) |   C |   180 | 19.9 |
    51547 | 2019-09-29 03:29:52 |          MASTER-IAC | (02h 40m 36.860s , +23d 55m 26.72s) |   C |   180 | 20.1 |
    51803 | 2019-09-29 03:34:09 |          MASTER-IAC | (02h 38m 14.592s , +21d 54m 59.78s) |   C |   180 | 20.0 |
    52057 | 2019-09-29 03:38:22 |          MASTER-IAC | (02h 46m 38.495s , +21d 59m 15.57s) |   C |   180 | 20.0 |

MASTER real time updated cover map of GRB190928A  and our upper limits are available at
https://master.sai.msu.ru/site/master2/ligo_1.php?id=10845

MASTER OT J020953.61+360533.8 discovery

During inspect, MASTER-Kislovodsk auto-detection system discovered OT source at
(RA, Dec) = 02h 09m 53.61s +36d 05m 33.8s on 2019-09-29.86025UT.

The OT unfiltered magnitude is 18.4m (mlimit 19.9m).
The OT is seen in 2 images. There is no minor planet at this place.

We have reference images without OT on 2014-10-28.91229 UT with unfiltered 
magnitude limit 20.6m, nearest in time on 2019-06-19 23:25:49 with mlim=18.2 (MASTER-Kislovodsk).

Our preliminary classification is CV, but 
Spectral observations are required.

The discovery and reference images are available at:
http://master.sai.msu.ru/static/OT/020953.61360533.8.png


GRB_name: GRB190928A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25868
SUBJECT: Konus-Wind observation of GRB 190928A
DATE:    19/09/30 11:29:55 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

D. Frederiks, S. Golenetskii, R.Aptekar, A. Kozlova,
A.Lysenko,  D. Svinkin, A. Tsvetkova,  M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:

The long, very bright GRB 190928A
(AGILE/MCAL detection: Ursi et al., GCN 25859;
IPN triangulation: Hurley et al., GCN 25864;
CALET Gamma-Ray Burst Monitor detection: Pal'shin et al., GCN 25865)
triggered Konus-Wind (KW) at T0=47536.665 s UT (13:12:16.665).

The burst light curve starts with a smooth pulse, which was followed,
after a period of low-level emission, by a much more intense,
multi-peaked emission complex. The total duration of the burst is ~195 s.
The emission is seen up to ~15 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB190928_T47536/

As observed by Konus-Wind, the burst had
a fluence of (4.9 Â± 0.3)x10^-4 erg/cm^2 and
a 256-ms peak energy flux, measured from T0+103.168,
of (9.0 Â± 0.2)x10^-5 erg/cm^2/s (both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum (measured from T0 to T0+185.334 s)
is best fit in the 20 keV - 20 MeV range
by the GRB (Band) function with the following model parameters:
the low-energy photon index alpha = -0.98 (-0.07,+0.07),
the high energy photon index beta = -1.97 (-0.13,+0.07),
the peak energy Ep = 591 (-88,+108) keV,
chi2 = 89/97 dof.

The spectrum near the peak count rate (measured from T0+103.168 s
to T0+103.424 s) is best fit in the 20 keV - 20 MeV range
by the GRB (Band) function with the following model parameters:
the low-energy photon index alpha = -0.72 (-0.25,+0.26),
the high energy photon index beta = -1.73 (-0.24,+0.09),
the peak energy Ep = 636 (-232,+754) keV,
chi2 = 72/57 dof.

All the quoted errors are estimated at the 90% confidence level.
All the presented results are preliminary.


GRB_name: GRB190928A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25879
SUBJECT: GRB 190928A: Insight-HXMT/HE detection
DATE:    19/09/30 15:50:41 GMT
FROM:    Qi Luo at IHEP  <luoqi@ihep.ac.cn>

Q. Luo, C. Cai, S. Xiao, Q. B. Yi, Y. G. Zheng, Y. Huang, 
C. K. Li, X. B. Li, G. Li, J. Y. Liao, S. L. Xiong, 
C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, A. M. Zhang, 
Y. F. Zhang, X. F. Lu, C. L. Zou (IHEP), Y. J. Jin, 
Z. Zhang (THU), T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, 
M. Wu, Y. P. Xu, S. N. Zhang (IHEP), 
report on behalf of the Insight-HXMT team:

At 2019-09-28T13:12:14.00 (T0), Insight-HXMT/HE detected 
GRB 190928A (trigger ID: HEB190928550) in a routine search of the data, 
which was also reported by AGILE/MCAL (GCN #25859), IPN triangulation 
(GCN #25864), CALET/GBM (GCN #25865) and Konus-Wind (GCN #25868). 

The Insight-HXMT/HE light curve mainly consists of multiple 
pulses with a duration (T90) of 31.10 s measured from T0+78.39 s. 
The 1-ms peak rate, measured from T0+102.88 s, is 23712 cnts/sec. 
The total counts from this burst is 152469 counts. The data of 
Insight-HXMT/HE suffers saturation in the brightest part.
URL_LC: http://www.hxmt.org/images/GRB/HEB190928550_lc.jpg 

All measurements above are made with the CsI detectors operating in the 
regular mode with the energy range of about 80-800 keV (deposited energy). 
Only gamma-rays with energy greater than about 200 keV can penetrate 
the spacecraft and leave signals in the CsI detectors installed inside 
of the telescope. 

Insight-HXMT is the first Chinese space X-ray telescope, which was 
funded jointly by the China National Space Administration (CNSA) and 
the Chinese Academy of Sciences (CAS). 
More information about it could be found at: 
http://www.hxmt.org.


GRB_name: GRB191001A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25893
SUBJECT: GRB 191001A: Fermi GBM Final Real-time Localization
DATE:    19/10/01 06:50:20 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 06:41:50 UT on 1 Oct 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 191001A (trigger 591604915.579128 / 191001279).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 308.9, Dec = 18.5 (J2000 degrees, equivalent to J2000 20h 35m, 18d 30'), with a statistical uncertainty of 3.3 degrees.

The angle from the Fermi LAT boresight is 102.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191001279/quicklook/glg_skymap_all_bn191001279.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191001279/quicklook/glg_healpix_all_bn191001279.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191001279/quicklook/glg_lc_medres34_bn191001279.gif


GRB_name: GRB191001A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25894
SUBJECT: GRB 191001A: BALROG localization (Fermi Trigger 591604915 / GRB 191001279)
DATE:    19/10/01 07:00:08 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

J. Burgess , F. Kunzweiler, B. Biltzinger, F. Berlato, & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
591604915 at 06:41:50 on 01 Oct. 2019 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 313.4+/-6.0 deg
Decl.(2000.0) = 15.1+/-1.4 deg
We estimate an additional systematic error of 2 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB191001279/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB191001279/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB191001279/json

                        


GRB_name: GRB191001B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25902
SUBJECT: GRB 191001B: Swift detection of a burst
DATE:    19/10/01 17:39:17 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

E. Troja (NASA/GSFC/UMCP), E. Ambrosi (INAF-IASFPA),
S. D. Barthelmy (GSFC), V. D'Elia (SSDC), J. A. Kennea (PSU),
N. J. Klingler (PSU), F. E. Marshall (NASA/GSFC), M. J. Moss (GWU),
B. Sbarufatti (PSU) and A. Tohuvavohu (Toronto) report on behalf of
the Neil Gehrels Swift Observatory Team:

At 17:19:20 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 191001B (trigger=927345).  Swift did not slew due to
targets with higher priority.  The BAT on-board calculated location is 
RA, Dec 86.368, -15.907 which is 
   RA(J2000)  =  05h 45m 28s
   Dec(J2000) = -15d 54' 25"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows several peaks
with a total duration of about 25 sec.  The peak count rate
was ~1600 counts/sec (15-350 keV), at ~20 sec after the trigger. 

Due to higher priority observations, Swift will not slew to the BAT position. 
There will thus be no prompt XRT or UVOT data for this trigger. 

Burst Advocate for this burst is E. Troja (eleonora.troja AT nasa.gov). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB191001B
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25906
SUBJECT: GRB 191001B: MITSuME Akeno optical upper limits
DATE:    19/10/01 18:52:08 GMT
FROM:    Katsuhiro L. Murata at Nagoya U  <murata@u.phys.nagoya-u.ac.jp>

K. L. Murata, R. Adachi,  M. Oeda, K.Shiraishi, K. Iida, M. Niwano,
F. Ogawa, R. Hosokawa, S. Toma, Y. Yatsu, and N. Kawai (TokyoTech)
report on behalf of the MITSuME collaboration:

We searched for the optical counterpart of GRB 191001B (E. Troja et
al., GCN Circular #25902) with the optical three color (g', Rc, and
Ic) CCD cameras attached to the MITSuME 50 cm telescope of Akeno
Observatory, Yamanashi, Japan.

The observation started on 17:22:09 UT. We did not find any new point
sources within the BAT on-board calculated error circle in all three bands.
We obtained the following 5-sigma limits for the magnitudes.

T0+[sec]   MID-UT    T-EXP[sec]    5-sigma limits
------------------------------------------------------------------------------------------------
~169       ~17:37    1680             g'>18.8, Rc>18.8, Ic>18.6
------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used GSC2.3 catalog for flux calibration.
The magnitudes are expressed in the AB system.


GRB_name: GRB191001A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25911
SUBJECT: GRB 191001A: DDOTI Optical Counterpart Candidate
DATE:    19/10/01 22:28:50 GMT
FROM:    Emma Margarita Pereyra Talamantes at IA-UNAM Ensenada  <mpereyra@astro.unam.mx>

Margarita Pereyra (UNAM), Alan M. Watson (UNAM), Nat Butler (ASU), Rosa L.
Becerra (UNAM), Diego Gonzalez (UNAM), Alexander Kutyrev (GSFC/UMD),
illiam H. Lee (UNAM), Eleonora Troja (GSFC/UMD), Gabriele Minervini
(INAF/IAPS-Rome)  and Tanner Wolfram (ASU), Simone Dichiara (GSFC/UMD)
report:

We observed the field of GRB 191001A (trigger 591604915, Fermi GBM Team,
GCN Circ. 25893) from 2019 Oct 1 06:48:21 UTC (391 seconds after the
trigger) to 06:59:52 UTC with the DDOTI wide-field imager at the
Observatorio Astronomico Nacional on Sierra San Pedro Martir (
http://ddoti.astroscu.unam.mx/). We calibrated our images against the APASS
catalog and obtained a 10-sigma limiting magnitude of w = 18.6.

Comparing our 10-sigma detections against the USNO-B1 and Pan-STARRS DR1
catalogues, we detect an uncatalogued source at 20:20:47.65 +15:05:03.4
that fades at the 2.4 sigma level from w = 16.7 to 17.0. Specifically, it
fades as a power-law in time since trigger with an index of -0.53 +/- 0.23.

Independently and roughly simultaneously, the source was detected at a
similar magnitude by ATLAS as ATLAS19wxr and is cataloged in the Transient
Name Server as AT2019rog (TNS Astronomical Transient Report 48331). The
discovery report states that it was not detected on 2019 Sep 29.

No known minor planets, brighter than V = 24.0, were found in the 5 arcmin
region around the source position at the time our observations were
performed.

The source is about 1 sigma from the Fermi Final Real-Time Localization and
BALROG positions (Fermi GBM Team, GCN Circ. 25893; Burgess et al., GCN
Circ. 25894). We suggest that it might be the optical counterpart of the
GRB and encourage further observations.

We thank the staff of the Observatorio Astronomico Nacional in San Pedro
Martir.
--


GRB_name: GRB191001A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25918
SUBJECT: GRB 191001A: RATIR Optical and NIR Observations
DATE:    19/10/02 04:57:45 GMT
FROM:    Emma Margarita Pereyra Talamantes at IA-UNAM Ensenada  <mpereyra@astro.unam.mx>

Margarita Pereyra (UNAM), Alan M. Watson (UNAM), Eleonora Troja (GSFC), Nat
Butler (ASU),  Alexander Kutyrev (GSFC), William H. Lee (UNAM), Diego
Gonzalez (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier
Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI), Owen
Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), JesÃºs GonzÃ¡lez (UNAM),
Carlos RomÃ¡n-ZÃºÃ±iga (UNAM), Harvey Moseley (GSFC), John Capone (UMD), V.
Zach Golkhou (U. Wash.), and Vicki Toy (UMD) report:

We observed the field of the candidate afterglow of GRB 191001A (trigger
591604915, Fermi GBM Team, GCN Circ. 25893, Pereyra et al. GCN Circ.
25911), centered at 20:20:47.65 +15:05:03.4,  with the Reionization and
Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m Harold
Johnson Telescope at the Observatorio AstronÃ³mico Nacional on Sierra San
Pedro MÃ¡rtir from 2019/10 2.12 to 2019/10 2.17 UTC (20.08 to 21.45 hours
after the Fermi trigger), obtaining a total of 0.34 hours exposure in the g
and r bands, 0.67 hours exposure in the i band and 0.37 hours exposure in
the i, Z, Y, J, and H bands.

At the position of the transient source AT2019rog discovered independently
by ATLAS and DDOTI, in comparison with the USNO-B1, PS1 and 2MASS catalogs,
we obtain the following upper limits (3-sigma):

  g > 23.20
  r > 23.01
  i > 23.26
  Z > 21.40
  Y > 21.49
  J > 21.22
  H > 20.92

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

The non-detection implies that the source has faded by about 6 magnitudes
in 20 hours. This is consistent with it being the afterglow of GRB 191001A.

We thank the staff of the Observatorio AstronÃ³mico Nacional in San Pedro
MÃ¡rtir.


GRB_name: GRB191001A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25919
SUBJECT: GRB 191001A: KAIT Optical Upper Limit
DATE:    19/10/02 05:54:41 GMT
FROM:    Weikang Zheng at UC Berkeley  <weikang@berkeley.edu>

WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on
behalf of the KAIT GRB team:

The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, responded to the GBM GRB 191001A (Fermi GBM team,
GCN 25893) starting at ~21.8 hours after the burst. We observed
the afterglow candidate AT2019rog, which was discovered independently
by ATLAS (Tonry et al., TNSTR 1954) and DDOTI (Pereyra et al., GCN 25911),
obtaining 17 x 60s images in the clear (roughly R) filters. We do not
detect the afterglow candidate in our co-add images with limiting mag
of ~21.5. Our non-detection result is consistent with observations from
RATIR (Pereyra et al., GCN 25918).


GRB_name: GRB191001A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25924
SUBJECT: GRB 191001A: Swift ToO observations
DATE:    19/10/02 14:08:17 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a ToO observation of the Fermi/GBM GRB 191001A. 
Automated analysis of the XRT data will be presented online at
https://www.swift.ac.uk/ToO_GRBs/00020949

Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. These are
not necessarily related to the Fermi/GBM event. Any X-ray source
considered to be a probable afterglow candidate will be reported via a 
GCN Circular after manual consideration.

Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).

This circular is an official product of the Swift-XRT team.


GRB_name: GRB191001A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25926
SUBJECT: IPN triangulation of GRB 191001A
DATE:    19/10/02 18:21:00 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, A. Kozlova,
and T. Cline on behalf of the Konus-Wind team,

K. Hurley, on behalf of the IPN, and

A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
on behalf of the Fermi GBM team, report:

The long duration GRB 191001A
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 25893;
BALROG localization: Burgess et al., GCN Circ. 25894)
was detected by Fermi (GBM trigger 591604915), Konus-Wind,
and Swift (BAT) at about 24110 s UT (06:41:50).
The burst was outside the coded field of view of the BAT.

We have triangulated this GRB to a Konus-GBM annulus centered at
RA(2000)=346.113 deg (23h 04m 27s) Dec(2000)=-7.939 deg (-7d 56' 21"),
whose radius is 46.475 +/- 2.251 deg (3 sigma).

The distance between the optical transient ATLAS19wxr
(Smartt, et al., GCN Circ. 25922; Pereyra et al., GCN Circ. 25911)
and the annulus center line is 9.3 arcmin,
supporting the association of the transient and the GRB.

This annulus may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB191001_T24130/IPN


GRB_name: GRB191001B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25930
SUBJECT: GRB 191001B: Swift-BAT refined analysis
DATE:    19/10/02 23:53:19 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

D. M. Palmer (LANL), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), T. Sakamoto (AGU),
M. Stamatikos (OSU), E. Troja (NASA/GSFC/UMCP),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-239 to T+962 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 191001B (trigger #927345)
(Troja et al., GCN Circ. 25902).  The BAT ground-calculated position is
RA, Dec = 86.423, -15.880 deg which is
   RA(J2000)  =  05h 45m 41.5s
   Dec(J2000) = -15d 52' 48.3"
with an uncertainty of 3.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 33%.

The mask-weighted light curve shows a multi-peaked structure that starts
at ~T-10 s and ends at ~T+130 s. T90 (15-350 keV) is 108.9 +- 15.1 sec
(estimated error including systematics).

The time-averaged spectrum from T-8.77 to T+126.11 sec is best fit by a
simple
power-law model.  The power law index of the time-averaged spectrum is
1.58 +- 0.11.  The fluence in the 15-150 keV band is 4.6 +- 0.3 x 10^-6
erg/cm2.
The 1-sec peak photon flux measured from T+20.44 sec in the 15-150 keV band
is 1.8 +- 0.4 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/927345/BA/


GRB_name: GRB190919A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25935
SUBJECT: GRB 190919A: AstroSat CZTI detection
DATE:    19/10/03 12:38:11 GMT
FROM:    Ramkrishna Gaikwad at IUCAA/AstroSat  <ramkrishna@iucaa.in>

R. Gaikwad, V. Sharma, D. Bhattacharya and A. Vibhute (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data showed the detection of a GRB 190919A, which was also detected by Fermi GBM Final Real-time Localization (GCN #25783).

The source was clearly detected in the 40-200 keV energy range. The light curve shows multiple pulses of emission with the strongest peak at 2019-09-19 18:20:02.0 UT. The measured peak count rate associated with the burst is 340 cts/s above the background in the combined data of four quadrants, with a total of 4389 cts. The local mean background count rate was 492 cts/s. Using cumulative rates, we measure a T90 of 42.6 s.

It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.

CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.


GRB_name: GRB190926A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25937
SUBJECT: GRB 190926A: Upper limit from CAHA 2.2m observation
DATE:    19/10/03 14:31:18 GMT
FROM:    Alexander Kann at IAA-CSIC  <kann@iaa.es>

M. Blazek, D. A. Kann (both HETH/IAA-CSIC), A. de Ugarte Postigo 
(HETH/IAA-CSIC, DARK/NBI), C. C. Thoene, K. Bensch, J. F. Agui (all 
HETH/IAA-CSIC), I. Hermelo, and S. Pedraz (both CAHA) report:

We observed the field of GRB 190926A (Melandri et al. GCN #25848) with 
the 2.2m  telescope at Calar Alto Observatory, Spain. The observation is 
centered 0.6523 days after the GRB and consisted of 3 x 360 s exposures 
in the V band for a total exposure time of 1080 s, obtained before 
technical problems shut down the observation sequence.

No new object is detected within the refined XRT error circle (Goad et 
al. GCN #25850) down to a 3-sigma limit of V(AB) = 21.9 mag, as compared 
to stars of the GSC 2.3 catalog. This is in agreement with the deep 
non-detection by OSN (Kann et al., GCN #25856).


GRB_name: GRB191001A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25938
SUBJECT: GRB 191001A: Fermi GBM observation
DATE:    19/10/03 17:42:48 GMT
FROM:    Rachel Hamburg at UAH  <rkh0007@uah.edu>

E. Bissaldi (Politecnico & INFN Bari), R. Hamburg (UAH)
and C. Meegan (UAH) report on behalf of the Fermi GBM Team:

"At 06:41:50.58 UT on 1 October 2019, the Fermi Gamma-Ray
Burst Monitor (GBM) triggered and located GRB 191001A
(trigger 591604915 / 191001279). The on-ground calculated
location has been reported in GCN #25893, and an IPN
annulus consistent with the GBM localization was reported
in GCN #25926. The ATLAS and DDOTI (GCN #25911) optical
counterpart position are consistent with the GBM localization.

The GBM light curve consists of several pulses
with a duration (T90) of about 24 s (50-300 keV).
The time-averaged spectrum from T0-4.99 s to T0+25.73 s
is best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -0.8 +/- 0.1
and the cutoff energy, parameterized as Epeak, is 114 +/- 9 keV.

The event fluence (10-1000 keV) in this time interval is
(4.7 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+15.7 s in the 10-1000 keV band
is 10.5 +/- 0.4 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support
Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB191001B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25940
SUBJECT: GRB 191001B: Optical Upper Limits with LCO
DATE:    19/10/03 18:30:36 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:

We observed Swift GRB 191001B (Barthelmy et al., GCN 25902) with the LCO 1-m Sinistro instrument on October 2, from 01:23 to 01:47 UT (corresponding to 5.73 to 6.2 hours from the GRB trigger time) with the SDSS r and i filters.

We performed a series of 5x120s exposures in each band. We do not detect any fading sources over the course of our observations in a 26.5' x 26.5' field of view centered around the Swift coordinates (Barthelmy et al., GCN 25902).  Using the USNO-B.1 catalog as reference, we obtain the following 3-sigma upper limits:


r > 18.82

i > 16.98

These observations were possible thanks to the USVI NASA-EPSCoR Research Infrastructure Development (RID) grant NNX16AL44A.


GRB_name: GRB191001A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25942
SUBJECT: GRB 191001A: Swift-XRT observations
DATE:    19/10/03 20:26:43 GMT
FROM:    Antonino D'Ai at IASF-PA  <antonino.dai@inaf.it>

D.N. Burrows (PSU), J. D. Gropp (PSU), A. Tohuvavohu (U. Toronto), K.L.
Page (U. Leicester), A.P. Beardmore (U. Leicester), P. D'Avanzo
(INAF-OAB), M.G. Bernardini (INAF-OAB), E. Ambrosi  (INAF-IASFPA)  and
P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team:

Swift-XRT has performed follow-up observations of the Fermi/GBM
detected burst GRB 191001A (GCN Circ. 25893, 25894), collecting 5.2 ks
of Photon Counting (PC) mode data between T0+114.2 ks and T0+161.3 ks.

No X-ray sources have been detected consistent with being within 2.0
arcsec of the likely associated optical transient AT2019rog (GCN Circ.
25911, 25918, 25919 and Tonry et al., TNSTR 1954). The 3-sigma upper
limit in the field ranges from ~0.002 to ~0.003 ct s^-1, corresponding
to a 0.3-10 keV observed flux of 8.6e-14 to 1.0e-13 erg cm^-2 s^-1
(assuming a typical GRB spectrum).

The results of the XRT-team automatic analysis of the XRT observations,
including a position-specific upper limit calculator, are available at
https://www.swift.ac.uk/ToO_GRBs/00020949.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB191004A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25945
SUBJECT: GRB 191004A: Swift detection of a burst with an optical detection
DATE:    19/10/04 18:30:53 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

S. B. Cenko (GSFC), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), A. D'Ai (INAF-IASFPA),
V. D'Elia (SSDC), J.D. Gropp (PSU), N. J. Klingler (PSU),
S Laha (CRESST/GSFC/UMD), A. Y. Lien (GSFC/UMBC),
F. E. Marshall (NASA/GSFC), M. J. Moss (GWU),
K. L. Page (U Leicester), B. Sbarufatti (PSU) and
A. Tohuvavohu (Toronto) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 18:07:02 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 191004A (trigger=927825).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 31.721, -36.932 which is 
   RA(J2000)  =  02h 06m 53s
   Dec(J2000) = -36d 55' 53"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a double-peaked
structure with a duration of about 5 sec.  The peak count rate
was ~8000 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 18:08:24.2 UT, 81.5 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 31.66950, -36.93368 which is equivalent
to:
   RA(J2000)  = 02h 06m 40.68s
   Dec(J2000) = -36d 56' 01.2"
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This
location is 148 arcseconds from the BAT onboard position, within the
BAT error circle. This position may be improved as more data are
received; the latest position is available at
http://www.swift.ac.uk/sper. No spectrum from the promptly downlinked
event data is yet available to determine the column density. 

UVOT took a finding chart exposure of 150 seconds with the White
filter  starting 84 seconds after the BAT trigger. Results from the
list of sources generated on-board shows an optical source consistent
with the XRT position.  Because there was not automatic aspect
solution for the image,  the precise position and magnitude will be
reported later.  The 2.7'x2.7' sub-image covers none of the XRT error
circle.  No correction has been made for the expected  extinction
corresponding to E(B-V) of 0.01. 

Burst Advocate for this burst is S. B. Cenko (brad.cenko AT nasa.gov). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB191004B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25947
SUBJECT: GRB 191004B: Swift detection of a burst with an optical counterpart
DATE:    19/10/04 21:43:36 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

S. B. Cenko (GSFC), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), A. D'Ai (INAF-IASFPA),
V. D'Elia (SSDC), J.D. Gropp (PSU), J. A. Kennea (PSU),
N. J. Klingler (PSU), N. P. M. Kuin (UCL-MSSL),
S Laha (CRESST/GSFC/UMD), A. Y. Lien (GSFC/UMBC),
F. E. Marshall (NASA/GSFC), M. J. Moss (GWU), D. M. Palmer (LANL) and
A. Tohuvavohu (Toronto) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 21:33:41 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 191004B (trigger=927839).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 49.177, -39.613, which is 
   RA(J2000)  =  03h 16m 42s
   Dec(J2000) = -39d 36' 46"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows multiple peaks
with a total duration of about 40 sec.  The peak count rate
was ~9500 counts/sec (15-350 keV), at ~3 sec after the trigger. 

The XRT began observing the field at 21:34:39.3 UT, 57.7 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
uncatalogued X-ray source located at RA, Dec 49.20403, -39.63494 which
is equivalent to:
   RA(J2000)  = 03h 16m 48.97s
   Dec(J2000) = -39d 38' 05.8"
with an uncertainty of 3.9 arcseconds (radius, 90% containment). This
location is 108 arcseconds from the BAT onboard position, within the
BAT error circle. This position may be improved as more data are
received; the latest position is available at
http://www.swift.ac.uk/sper. No spectrum from the promptly downlinked
event data is yet available to determine the column density. 

The initial flux in the 2.5 s image was 1.81e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 68 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  = 03:16:49.10 =  49.20458
  DEC(J2000) = -39:38:03.3  = -39.63425
with a 90%-confidence error radius of about 0.62 arc sec. This position is 2.9
arc sec. from the center of the XRT error circle. The estimated magnitude is
18.00 with a 1-sigma error of about  0.14. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.02. 

Burst Advocate for this burst is S. B. Cenko (brad.cenko AT nasa.gov). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB191004B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25949
SUBJECT: GRB 191004B: Optical Afterglow Detection with LCO
DATE:    19/10/04 23:55:39 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:

We observed Swift GRB 191004B (Palmer et al., GCN 25947) with
the LCO 1-m Sinistro instrument on September 4, from 21:50 to 22:07 UT
(corresponding to 0.11 to 0.4 hours from the GRB trigger time)
with the Bessel R filter.

We performed a series of 5x180s exposures, and we detect a source not present in either USNO-B1.0 or 2MASS surveys consistent with the optical afterglow location (Palmer et al., GCN 25947
) with the following magnitude:

R = 18.07 +/- 0.02

This flux is calibrated against several USNO-B1.0 objects near the GRB location but is not corrected for Galactic Extinction.

These observations were possible thanks to the USVI NASA-EPSCoR
Research Infrastructure Development (RID) grant NNX16AL44A.


GRB_name: GRB191004A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25950
SUBJECT: GRB 191004A: Enhanced Swift-XRT position
DATE:    19/10/05 00:20:01 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 2401 s of XRT Photon Counting mode data and 5 UVOT
images for GRB 191004A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 31.66842, -36.93302 which is equivalent
to:

RA (J2000): 02h 06m 40.42s
Dec (J2000): -36d 55' 58.9"

with an uncertainty of 1.7 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB191004B
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25951
SUBJECT: GRB 191004B: Enhanced Swift-XRT position
DATE:    19/10/05 01:36:47 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 162 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 191004B, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 49.20398, -39.63502 which is equivalent
to:

RA (J2000): 03h 16m 48.96s
Dec (J2000): -39d 38' 06.1"

with an uncertainty of 2.0 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB191004A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25952
SUBJECT: GRB 191004A: NOT optical upper limits
DATE:    19/10/05 03:47:35 GMT
FROM:    Kasper Elm Heintz at Univ. of Iceland and DAWN/NBI  <keh14@hi.is>

K. E. Heintz (Univ. of Iceland), D. B. Malesani (DTU space), and S. Moran (NOT), report on behalf of a larger collaboration:

We observed the field of the Swift-detected GRB 191004A (Cenko et al., GCN 25945) with the Nordic Optical Telescope (NOT) equipped with StanCAM. We obtained 3x300s exposures with the Bessel R filter starting at 02:10:34 UT on October 5 (i.e. 8.05 hr post-burst). We do not detect the previously reported optical afterglow (Cenko et al., GCN 25945; Lipunov et al., GCN 25944), down to a limit of R > 23.5 mag, calibrated against the photometry of nearby field stars from the USNO-B1 catalog. 


GRB_name: GRB191004A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25953
SUBJECT: GRB 191004A: Swift-BAT refined analysis
DATE:    19/10/05 03:50:01 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

T. Sakamoto (AGU), S. D. Barthelmy (GSFC), J. R. Cummings (CPI),
S. B. Cenko (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL),
M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-61 to T+242 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 191004A (trigger #927825)
(Cenko, et al., GCN Circ. 25945).  The BAT ground-calculated position is
RA, Dec = 31.716, -36.932 deg, which is
   RA(J2000)  =  02h 06m 51.8s
   Dec(J2000) = -36d 55' 54.0"
with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 26%.

The mask-weighted light curve has two overlapping peaks starting at
~T-0.2 sec, peaking at ~T_zero, and ending at ~3.1 sec.
T90 (15-350 keV) is 2.44 +- 0.08 sec (estimated error including systematics).

The time-averaged spectrum from T-0.09 to T+2.58 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.35 +- 0.08.  The fluence in the 15-150 keV band is 1.3 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T-0.09 sec in the 15-150 keV band
is 7.8 +- 0.5 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/927825/BA/


GRB_name: GRB191004B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25954
SUBJECT: GRB 191004B: NOT optical photometry
DATE:    19/10/05 03:58:45 GMT
FROM:    Kasper Elm Heintz at Univ. of Iceland and DAWN/NBI  <keh14@hi.is>

K. E. Heintz (Univ. of Iceland), D. B. Malesani (DTU space), and S. Moran (NOT), report on behalf of a larger collaboration:

We observed the field of the Swift-detected GRB 191004B (Cenko et al., GCN 25947) with the Nordic Optical Telescope (NOT) equipped with StanCAM. We obtained 3x300s exposures with the Bessel R filter starting at 02:30:07 UT on October 5 (i.e. 4.94 hr post-burst). We clearly detect the optical afterglow (Cenko et al., GCN 25947; Lipunov et al., GCN 25948; Strausbaugh & Cucchiara, GCN 25949) and measure a magnitude of R = 20.87 +/- 0.05 mag in the stacked image. We calibrated the photometry assuming for the USNO star at (RA, Dec) = (03:16:54.39, -39:37:41.5) a magnitude of R = 16.97 mag. The derived magnitude for the GRB afterglow is not corrected for the Galactic extinction.


GRB_name: GRB191004B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25955
SUBJECT: GRB 191004B: Swift-BAT refined analysis
DATE:    19/10/05 04:07:48 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

M. Stamatikos (OSU), S. D. Barthelmy (GSFC), S. B. Cenko (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF), S. Laha (GSFC/UMBC),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Sakamoto (AGU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-60 to T+243 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 191004B (trigger #927839)
(Cenko, et al., GCN Circ. 25947).  The BAT ground-calculated position is
RA, Dec = 49.200, -39.637 deg, which is
   RA(J2000)  =  03h 16m 47.9s
   Dec(J2000) = -39d 38' 15.0"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 97%.

The mask-weighted light curve shows multiple overlapping peaks starting at
T-1 sec, peaking at ~T+7 sec, and ending at ~T+45 sec.
T90 (15-350 keV) is 37.7 +- 14.9 sec (estimated error including systematics).

The time-averaged spectrum from T-1.45 to T+56.17 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.10 +- 0.08.  The fluence in the 15-150 keV band is 2.5 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+2.75 sec in the 15-150 keV band
is 5.0 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/927839/BA/


GRB_name: GRB191004B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25956
SUBJECT: GRB 191004B: VLT/X-shooter redshift
DATE:    19/10/05 08:40:16 GMT
FROM:    Valerio D'Elia at ASDC  <valerio.delia@ssdc.asi.it>

V. D'Elia (SSDC), J. P. U. Fynbo (DAWN/NBI), L. Izzo (DARK/NBI), D. B. Malesani (DTU Space), K. E. Heintz (Univ. of Iceland), N. R. Tanvir (Univ. Leicester), A. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), S. D. Vergani (CNRS -GEPI/Observatorie de Paris) report on behalf of the Stargate collabaration:
We observed the optical afterglow (Lipunov et al., GCN 25948, Strausbaugh et al., GCN 25949) of the Swift/BAT GRB 191004B (Cenko et al., GCN 25947) using the ESO VLT UT2 (Kueyen) equipped with the X-shooter spectrograph. Our spectra cover the wavelength range 3000-21000 AA, and consist of 6 exposures by 600 s each. The observation mid time was 2019 Oct 05 at about 5:30 UT (8 hr after the GRB).
In a 30 s image taken with the acquisition camera on Oct 05.1989 UT, we detect the optical afterglow, for which we measure a magnitude r = 21.23 +- 0.03 AB (calibrated against nearby stars from the SkyMapper catalog; Wolf et al. 2018, PASA, 35, 010; https:doi.org/10.4225/41/593620ad5b574).

We clearly detect continuum over the full covered wavelength range. A strong absorption is visible around 5474 AA, and an emission feature at 5479 AA, which we identify as due to H I. This is confirmed by the presence of the Ly alpha forest blueward of this wavelength. We also detect other narrower absorption features which we interpret as due to e.g. C IV and Si IV at a common redshift z = 3.503. The continuum is well detected down to ~800 AA rest frame, i.e, below the Lyman limit.
We also detect an intervening absorber (Mg II, Fe II) at z=2.137
We acknowledge excellent support from the ESO observing staff in Paranal, in particular Camila Navarrete and Bin Yang.


GRB_name: GRB191004A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25957
SUBJECT: GRB 191004A: Swift-XRT refined Analysis
DATE:    19/10/05 18:31:05 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J. D. Gropp (PSU), A. Tohuvavohu (U. Toronto), A.P. Beardmore (U.
Leicester), P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester),
M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) , M. Capalbi
(INAF-IASFPA), J.A. Kennea (PSU) and V. Lipunov report on behalf of the
Swift-XRT team: report on behalf of the Swift-XRT team:

We have analysed 4.8 ks of XRT data for GRB 191004A (Lipunov et al. GCN
Circ. 25944), from 86 s to 12.4 ks after the  BAT trigger. The data
comprise 88 s in Windowed Timing (WT) mode with the remainder in Photon
Counting (PC) mode. The enhanced XRT position for this burst was given
by Osborne et al. (GCN Circ. 25950).

The light curve can be modelled with an initial power-law decay with an
index of alpha=0.74 (+0.07, -0.08), followed by a break at T+883 s to
an alpha of 1.36 (+0.34, -0.10).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.04 (+0.21, -0.13). The
best-fitting absorption column is  2.0 (+3.8, -0.5) x 10^20 cm^-2,
consistent with the Galactic value of 1.5 x 10^20 cm^-2 (Willingale et
al. 2013). The PC mode spectrum has a photon index of 1.81 (+0.14,
-0.13) and a best-fitting absorption column of 6.0 (+3.4, -3.1) x 10^20
cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 3.6 x 10^-11 (4.0 x 10^-11) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      6.0 (+3.4, -3.1) x 10^20 cm^-2
Galactic foreground: 1.5 x 10^20 cm^-2
Excess significance: 2.4 sigma
Photon index:      1.81 (+0.14, -0.13)

If the light curve continues to decay with a power-law decay index of
1.36, the count rate at T+24 hours will be 2.9 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.1 x
10^-13 (1.2 x 10^-13) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00927825.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB191004B
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25958
SUBJECT: GRB 191004B: COATLI Optical Observations
DATE:    19/10/06 03:15:25 GMT
FROM:    Alan M Watson at UNAM  <alan@astro.unam.mx>

Alan M. Watson (UNAM),  Nat Butler (ASU), Rosa L. Becerra (UNAM), Diego GonzÃ¡lez
(UNAM), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Margarita Pereyra
(UNAM), and Eleonora Troja (GSFC) report:

We observed the field of GRB 191004B (Cenko et al., GCN Circ. 25947) with the
COATLI 50-cm telescope and interim imager at the Observatorio AstronÃ³mico
Nacional on the Sierra de San Pedro MÃ¡rtir (http://coatli.astroscu.unam.mx) from
2019-10-05 06:54 to 12:11, obtaining a total of 1.65 hours of exposure in the w
filter.

At the position of the bright afterglow detected by Swift/UVOT (Cenko et al.,
GCN Circ. 25947), we detect a source with w = 21.47 +/- 0.17.

Our w magnitudes are calibrated against the Pan-STARRS1 catalog, are on an
approximate AB system (Becerra et al., 2019, ApJ, 872, 118), and are not
corrected for Galactic extinction in the direction of the GRB.

We thank the COATLI technical team and the staff of the Observatorio AstronÃ³mico
Nacional.


GRB_name: GRB191004A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25959
SUBJECT: GRB 191004A: GROND Upper limits
DATE:    19/10/06 10:23:06 GMT
FROM:    Patricia Schady at Swift  <p.schady@bath.ac.uk>

P. Schady (Univ. of Bath), J. Balmer (MPE Garching), and A. Nicuesa Guelbenzu (TLS Tautenburg) report:


We observed the field of GRB 191004A (Swift trigger 927825; Cenko et al., GCN #25945) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La Silla Observatory (Chile).


Observations started at 01:56 UT on 5th October, 7.8 hours after the GRB trigger. They were performed at an average seeing of 1.4" and at an average airmass of 1.5.


We do not detect a source at the position of the Swift-XRT and MASTER afterglow (Osborne et al., GCN #25950; Lipunov et al., GCN #25944) down to the following 3-sigma limits (all AB magnitude):


g' > 23.7 mag
r' > 24.2 mag
i' > 23.5 mag
z' > 23.3 mag
J > 21.4 mag
H > 20.4 mag
K > 19.9 mag


The given limits are derived based on calibrating the images against Sky-Mapper and 2MASS field stars and are not corrected for the Galactic foreground extinction corresponding to a reddening of E_(B-V)= 0.01 in the direction of the burst (Schlafly & Finkbeiner 2011).

We acknowledge the excellent support from Regis Lachaume in La Silla in acquiring these observations.


GRB_name: GRB191004B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25960
SUBJECT: GRB 191004B: GROND Detection of the Optical/NIR Afterglow
DATE:    19/10/06 10:24:52 GMT
FROM:    Patricia Schady at Swift  <p.schady@bath.ac.uk>

P. Schady (Univ. of Bath), J. Balmer (MPE Garching), and A. Nicuesa Guelbenzu (TLS Tautenburg) report:


We observed the field of GRB 191004B (Swift trigger 927839; Cenko et al., GCN #25947) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La Silla Observatory (Chile).


Observations started at 02:25 UT on 5th October, 4.9 hours after the GRB trigger. They were performed at an average seeing of 1.5" and at an average airmass of 1.8.


We detect a single point source consistent with the position of the Swift-XRT and MASTER afterglow (Beardmore et al., GCN # 25951; Lipunov et al., GCN # 25948) in all optical and NIR bands apart from K. In an 8 min exposure, we measure an AB magnitude in the r band filter of r' = 20.86 +/- 0.04 mag.


The optical and NIR afterglow is still clearly detected in a second epoch of observations taken on the night of 6th October, with an AB magnitude r' = 22.10 +/- 0.03 mag.

The above magnitudes are calibrated again sky-mapper, and not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V)=0.01 in the direction of the burst (Schlafly & Finkbeiner 2011).

We acknowledge the excellent support from Regis Lachaume in La Silla in acquiring these observations.


GRB_name: GRB191004B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25961
SUBJECT: GRB 191004B: Swift-XRT refined Analysis
DATE:    19/10/06 12:41:44 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

A. Tohuvavohu (U. Toronto), J.P. Osborne (U. Leicester), K.L. Page (U.
Leicester), E. Ambrosi (INAF-IASFPA) , M. Capalbi (INAF-IASFPA), M.
Perri (ASDC), J.A. Kennea (PSU), B. Sbarufatti (PSU), 
 and S.B. Cenko report on behalf of the Swift-XRT team:

We have analysed 8.6 ks of XRT data for GRB 191004B (Cenko et al. GCN
Circ. 25947), from 63 s to 102.9 ks after the  BAT trigger. The data
comprise 142 s in Windowed Timing (WT) mode with the remainder in
Photon Counting (PC) mode. The enhanced XRT position for this burst was
given by Beardmore et al. (GCN Circ. 25951).

The light curve can be modelled with an initial power-law decay with an
index of alpha=2.9 (+0.6, -0.7), followed by a break at T+94.6 s to an
alpha of 1.073 (+0.031, -0.027).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.75 (+0.09, -0.07). The
best-fitting absorption column is  1.4 (+6.8, -1.4) x 10^21 cm^-2, at a
redshift of 3.503, in addition to the Galactic value of 1.9 x 10^20
cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index
of 1.54 (+0.21, -0.14) and a best-fitting absorption column of 2 (+178,
-2) x 10^20 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux
conversion factor deduced from this spectrum  is 4.2 x 10^-11 (4.3 x
10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Galactic foreground: 1.9 x 10^20 cm^-2
Intrinsic column:    2 (+178, -2) x 10^20 cm^-2 at z=3.503
Photon index:      1.54 (+0.21, -0.14)

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00927839.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB190928A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25965
SUBJECT: GRB 190928A: AstroSat CZTI detection
DATE:    19/10/07 06:44:14 GMT
FROM:    Ramkrishna Gaikwad at IUCAA/AstroSat  <ramkrishna@iucaa.in>

R. Gaikwad, V. Sharma and D. Bhattacharya (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data showed the detection of a GRB 190928A, which was also detected by AGILE/MCAL (Ursi A. et al., GCN # 25859), IPN Triangulation (Hurley K. et al., GCN # 25864), CALET Gamma-ray Burst Monitor (Valentin P. et al., GCN # 25865), MASTER optical observations (Lipunov L. et al., GCN # 25867), Konus-Wind observation (Frederiks D. et al., GCN # 25868) and Insight-HXMT/HE (Luo Q. et al., GCN # 25879).

The source was clearly detected in the 40-200 keV energy range. The light curve shows multiple pulses of emission with the strongest peak at 2019-09-28 13:12:16.0 UT. The measured peak count rate associated with the burst is 3601 cts/s above the background in the combined data of four quadrants, with a total of 52582 cts. The local mean background count rate was 494 cts/s. Using cumulative rates, we measure a T90 of 114.6 s. In preliminary analysis, we find that 4621 Compton events are associated with this event.

It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.

CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.


GRB_name: GRB191004A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25971
SUBJECT: GRB 191004A: Optical Detection with LCO
DATE:    19/10/07 16:14:13 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:

We observed Swift GRB 191004A (Barthelmy et al., GCN 25945) with
the LCO 1-m Sinistro instrument on September 4, from 20:12 to 20:47 UT
(corresponding to 1.70 to 2.28 hours from the GRB trigger time)
with the Bessel R and I filters.

We performed a series of 10x180s exposures in each band.  We do not detect a significant source in individual frames, but we do  detect a source in co-added frames that is not present in either USNO-B1.0 or 2MASS surveys and is consistent with the optical afterglow location (Evans et al., GCN 25950) with the following magnitudes:

R = 22.89 +/- 0.10
I = 21.00 +/- 0.09


This flux is calibrated against several USNO-B1.0 objects near the GRB location but is not corrected for Galactic Extinction.

These observations were possible thanks to the USVI NASA-EPSCoR
Research Infrastructure Development (RID) grant NNX16AL44A.


GRB_name: GRB191004A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25972
SUBJECT: GRB 191004A: Swift/UVOT Detection
DATE:    19/10/07 17:39:25 GMT
FROM:    Sam LaPorte at PSU  <sjl5346@psu.edu>

GRB 191004A: Swift/UVOT Detection

S. J. LaPorte (PSU) and S. B. Cenko (GSFC)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 191004A
84 s after the BAT trigger (Cenko et al., GCN Circ. 25945).
A fading source consistent with the XRT position
(Osborne et al. GCN Circ. 25950)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

b                       582             775             38         >18.83
uvm2                680             873             38         >18.00
u                       327             750           265         >19.60
v                       656            1104            58         >18.06
uvw1                705              898            38         >17.89
uvw2                632            1080            58         >18.28
white                115            1054          333           19.78+-0.16

white              5567          12438          956         >21.24

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.01 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB191004A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25973
SUBJECT: Konus-Wind observation of GRB 191004A
DATE:    19/10/07 17:53:55 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks,
M. Ulanov, A. Tsvetkova, A. Lysenko, A. Kozlova, and T. Cline
on behalf of the Konus-Wind team, report:

The long-duration GRB 191004A
(Swift-BAT detection: Cenko et al., GCN circ. 25945;
Sakamoto et al., GCN circ. 25953)
triggered Konus-Wind at T0=65226.378 s UT (18:07:06.378).

The burst light curve shows a multi-peaked structure
which starts at ~T0-0.2 s and has a total duration of ~5 s.
The emission is seen up to ~1 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB191004_T65226/

As observed by Konus-Wind, the burst
had a fluence of 2.00(-0.41,+0.62)x10^-6 erg/cm2,
and a 64-ms peak flux, measured from T0+1.872 s,
of 2.38(-0.83,+1.02)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+8.448 s)
is best fit in the 20 keV - 2 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -0.69(-0.61,+0.83)
and Ep = 157(-37,+95) keV (chi2 = 49/57 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.0
(chi2 = 48/56 dof).

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.


GRB_name: GRB191004B
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25974
SUBJECT: Konus-Wind observation of GRB 191004B
DATE:    19/10/07 18:00:56 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks,
M. Ulanov, A. Tsvetkova, A. Lysenko, A. Kozlova, and T. Cline
on behalf of the Konus-Wind team, report:

The long-duration GRB 191004B
(Swift-BAT detection: Cenko et al., GCN circ. 25947;
Stamatikos et al., GCN circ. 25955)
triggered Konus-Wind at T0=77626.99 s UT (21:33:46.990).

The burst light curve shows a multi-peaked structure
which starts at ~T0-0.5 s and has a total duration of ~5.5 s.
The emission is seen up to ~1 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB191004_T77626/

As observed by Konus-Wind, the burst
had a fluence of 4.13(-0.40,+0.45)x10^-6 erg/cm2,
and a 64-ms peak flux, measured from T0+3.504 s,
of 2.56(-0.73,+0.74)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+8.448 s)
is best fit in the 20 keV - 10 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -0.51(-0.30,+0.34)
and Ep = 172(-21,+27) keV (chi2 = 59/57 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -3.0
(chi2 = 59/56 dof).

Assuming the redshift z=1.260 (D'Elia et al., GCN circ. 25956)
and a standard cosmology model with H_0 = 67.3 km/s/Mpc,
Omega_M = 0.315, and Omega_Lambda = 0.685 (Planck Collaboration, 2014),
we estimate the following rest-frame parameters:
the isotropic energy release E_iso is 1.79(-0.17,+0.20)x10^52 erg,
the peak luminosity L_iso is 2.51(-0.72,+0.73)x10^52 erg/s,
and the rest-frame peak energy of the time-integrated spectrum,
Ep,i, is 389(-47,+61) keV.
With these energetics, the burst lies within the 90% prediction bands
for both 'Amati' and 'Yonetoku' relations built for the sample
of 138 long KW GRBs with known redshifts
(Tsvetkova et al., ApJ 850 161, 2017).

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.


GRB_name: GRB191004B
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25976
SUBJECT: GRB 191004B: Correction to Konus-Wind GCN 25974
DATE:    19/10/07 19:14:38 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin reports on behalf of the Konus-Wind team:

The redshift of GRB 191004B mentioned in GCN 25974 was incorrect,
the correct one is z = 3.503 (D'Elia et al., GCN circ. 25956).

Thus, assuming the redshift z=3.503 and a standard cosmology model with
H_0 = 67.3 km/s/Mpc, Omega_M = 0.315, and Omega_Lambda = 0.685
(Planck Collaboration, 2014),
we estimate the following rest-frame parameters:
the isotropic energy release E_iso is 1.08(-0.10,+0.12)x10^53 erg,
the peak luminosity L_iso is 3.01(-0.86,+0.87)x10^53 erg/s,
and the rest-frame peak energy of the time-integrated spectrum,
Ep,i, is 775(-95,+122) keV.
With these energetics, the burst lies within the 68% prediction bands
for both 'Amati' and 'Yonetoku' relations built for the sample
of 138 long KW GRBs with known redshifts
(Tsvetkova et al., ApJ 850 161, 2017).

I apologize for possible inconvenience.


GRB_name: GRB191004B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25977
SUBJECT: GRB 191004B: Continued Optical Afterglow Monitoring with LCO
DATE:    19/10/07 20:11:14 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:

We obtained a second epoch (first epoch, GCN 25949) of Swift GRB 191004B (Palmer et al., GCN 25947) data with
the LCO 1-m Sinistro instrument at the Sutherland Site (SAAO) on September 5, from 2:40 to 3:03 UT
(corresponding to 4.95 to 5.3 hours from the GRB trigger time)
with the Bessel R and I filters.

We performed a series of 5x240s exposures, and we detect the afterglow with the following magnitudes:

R = 21.01 +/- 0.08
I = 19.91 +/- 0.08

This flux is calibrated against several USNO-B1.0 objects near the GRB location but is not corrected for Galactic Extinction.

These observations were possible thanks to the USVI NASA-EPSCoR
Research Infrastructure Development (RID) grant NNX16AL44A.


GRB_name: GRB191004B
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25978
SUBJECT: GRB 191004B: Swift/UVOT Detection
DATE:    19/10/07 20:45:09 GMT
FROM:    Sam LaPorte at PSU  <sjl5346@psu.edu>

GRB 191004B: Swift/UVOT Detection

S. J. LaPorte (PSU) and S. B. Cenko (GSFC)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 191004B
69 s after the BAT trigger (Cenko et al., GCN Circ. 25947).
A fading source consistent with the XRT position
(Beardmore et al. GCN Circ. 25951)
is detected in the initial UVOT exposures.

The preliminary UVOT position is:
    RA  (J2000) =  03:16:49.10 =  49.20459 (deg.)
    Dec (J2000) = -39:38:03.9  = -39.63441 (deg.)
with an estimated uncertainty of 0.43 arc sec. (radius, 90% confidence),
consistent with the positions reported by LCO (Strausbaugh et al. GCN Circ.
25949),
NOT (Heintz et al. GCN Circ. 25954), VLT/X-Shooter (D'Elia et al. GCN Circ.
25956),
COATLI (Watson et al. GCN Circ. 25958), and GROND (Schady et al. GCN Circ.
25960).

Preliminary detections and 3-sigma upper limits using the UVOT photometric
system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures
are:

Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

b                    38697         38997          295           >20.42
uvm2             44827         45727          885           >20.25
u                       294              387            91           >19.04

v                    43916         44822          885           >20.07
uvw1             45734         46281          538            >19.96
uvw2             39915         40544          618            >20.09
white                   82             232          147
18.01+-0.05
white             39003         39909          885              20.51+-0.13



The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB191008A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25979
SUBJECT: GRB 191008A: Fermi GBM Final Real-time Localization
DATE:    19/10/08 07:17:16 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 07:06:59 UT on 8 Oct 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 191008A (trigger 592211224.080392 / 191008297).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 61.7, Dec = 51.0 (J2000 degrees, equivalent to J2000 04h 06m, 51d 00'), with a statistical uncertainty of 19.1 degrees.

The angle from the Fermi LAT boresight is 86.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191008297/quicklook/glg_skymap_all_bn191008297.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191008297/quicklook/glg_healpix_all_bn191008297.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191008297/quicklook/glg_lc_medres34_bn191008297.gif


GRB_name: GRB191004A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25981
SUBJECT: GRB 191004A: CALET Gamma-Ray Burst Monitor detection
DATE:    19/10/08 12:30:46 GMT
FROM:    Valentin Pal'shin at AGU  <val@phys.aoyama.ac.jp>

K. Yamaoka (Nagoya U),
A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU),
Y. Kawakubo (LSU), S. Nakahira (RIKEN),
Y. Asaoka, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U),
N. Cannady (GSFC/UMBC), M. L. Cherry (LSU),
S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The soft GRB 191004A (Swift-BAT detection: Cenko et al., GCN Circ. 25945,
Sakamoto et al., GCN Circ. 25953; Konus-Wind observation: Svinkin et al.,
GCN Circ. 25973) triggered the CALET Gamma-ray Burst Monitor (CGBM) at
18:07:05.528 UTC on 4 October 2019. The burst signal was seen by all CGBM
detectors.
No real-time CGBM GCN notice was distributed about this trigger because
the real-time communication from the ISS was off (loss of signal).

The burst light curve shows two pulses which start at T-2.7 sec and end
at T+0.0 sec. The T90 and T50 durations measured by the SGM data are
2.6 +- 0.3 sec and 1.9 +- 1.4 sec (40-1000 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1254247608/

The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at the Waseda University.


GRB_name: GRB191009A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25985
SUBJECT: GRB 191009A: Fermi GBM Final Real-time Localization
DATE:    19/10/09 07:19:20 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 07:08:56 UT on 9 Oct 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 191009A (trigger 592297741.769374 / 191009298).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 26.8, Dec = 65.7 (J2000 degrees, equivalent to J2000 01h 47m, 65d 42'), with a statistical uncertainty of 1.4 degrees.

The angle from the Fermi LAT boresight is 40.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191009298/quicklook/glg_skymap_all_bn191009298.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191009298/quicklook/glg_healpix_all_bn191009298.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191009298/quicklook/glg_lc_medres34_bn191009298.gif


GRB_name: GRB191009A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25986
SUBJECT: GRB 191009A: BALROG localization (Fermi Trigger 592297741 / GRB 191009298)
DATE:    19/10/09 07:38:41 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

B. Biltzinger, F. Kunzweiler, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
592297741 at 07:08:56 on 09 Oct. 2019 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 30.0+/-5.9 deg
Decl.(2000.0) = 67.1+/-2.1 deg
We estimate an additional systematic error of 2 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB191009298/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB191009298/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB191009298/json

                        


GRB_name: GRB191011A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25987
SUBJECT: GRB 191011A: Fermi GBM Final Real-time Localization
DATE:    19/10/11 04:46:15 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 04:35:58 UT on 11 Oct 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 191011A (trigger 592461363.582334 / 191011192).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 207.9, Dec = 57.8 (J2000 degrees, equivalent to J2000 13h 51m, 57d 47'), with a statistical uncertainty of 4.0 degrees.

The angle from the Fermi LAT boresight is 169.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191011192/quicklook/glg_skymap_all_bn191011192.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191011192/quicklook/glg_healpix_all_bn191011192.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191011192/quicklook/glg_lc_medres34_bn191011192.gif


GRB_name: GRB191011A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25988
SUBJECT: GRB 191011A: Swift detection of a burst with an optical counterpart
DATE:    19/10/11 04:46:45 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

S. L Laha (GSFC/UMBC/CRESST), C. Gronwall (PSU), J.D. Gropp (PSU),
N. P. M. Kuin (UCL-MSSL), A. Y. Lien (GSFC/UMBC),
K. L. Page (U Leicester), D. M. Palmer (LANL) and
E. Troja (NASA/GSFC/UMCP) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 04:35:56 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 191011A (trigger=928924).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 44.724, -27.845 which is 
   RA(J2000) = 02h 58m 54s
   Dec(J2000) = -27d 50' 40"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a complex peak
structure with a duration of about 20 sec.  The peak count rate
was ~3000 counts/sec (15-350 keV), at ~1 sec after the trigger. 

The XRT began observing the field at 04:37:11.1 UT, 74.8 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 44.72679, -27.84594 which is equivalent
to:
   RA(J2000)  = 02h 58m 54.43s
   Dec(J2000) = -27d 50' 45.4"
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This
location is 9.5 arcseconds from the BAT onboard position, within the
BAT error circle. This position may be improved as more data are
received; the latest position is available at
http://www.swift.ac.uk/sper.  We cannot determine whether the source is
fading at the present time. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (1.54 x
10^20 cm^-2, Willingale et al. 2013), with an excess column of 5.8
(+3.35/-2.89) x 10^21 cm^-2 (90% confidence). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 77 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  = 02:58:54.80 =  44.72832
  DEC(J2000) = -27:50:43.5  = -27.84541
with a 90%-confidence error radius of about 0.83 arc sec. This position is 6.1
arc sec. from the center of the XRT error circle. The estimated magnitude is
20.20 with a 1-sigma error of about  0.19. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.02. 

Burst Advocate for this burst is S. L Laha (sib.laha AT gmail.com). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB191011A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25991
SUBJECT: GRB 191011A: VLT X-shooter redshift from RRM Observations
DATE:    19/10/11 06:19:02 GMT
FROM:    Alexander Kann at IAA-CSIC  <kann@iaa.es>

D. B. Malesani (DTU Space), A. de Ugarte Postigo (HETH/IAA-CSIC, 
DARK/NBI), D. A. Kann (HETH/IAA-CSIC), V. D'Elia (SSDC), J. P. U. Fynbo 
(DAWN/NBI), and G. Pugliese (Univ. Amsterdam) report on behalf of the 
Stargate Consortium:

We observed the localization of the Swift GRB 191011A (Laha et al., GCN 
25988) with X-shooter on the VLT in RRM mode. The optical afterglow 
(Laha et al., GCN 25988, Lipunov et al., GCN 25989) is well-detected, 
and we measure a magnitude of r' = 19.18 +/- 0.06 mag (AB) from the 15 s 
acquisition image obtained starting at 2019-10-11T04:59:12.540, 23.28 
min after the trigger, measured against PanSTARRS field stars.

In the first spectrum (integration time 175 s) we detect Ly-a, SII, OI, 
SiII, CII, SiIV, CIV, FeII, CI, AlII, AlIII, MnII, MgII, MgI, and FeII*, 
all at a common redshift z=1.722. We consider this the redshift of GRB 
191011A. We furthermore report the presence of an intervening MgII 
system at z=1.2072.

We acknowledge excellent support from the ESO observing staff in 
Paranal, in particular Chiara Mazzucchelli, Rodrigo Palominos, and 
Camila Navarrete.

NB: We note the detection of a Fermi GRB (The Fermi GBM team, GCN 25987) 
at essentially the same time and with similar light curve structure, 
however, this GRB is localized to the northern hemisphere.


GRB_name: GRB191011A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25992
SUBJECT: GRB 191011A: GROND Detection of the Optical/NIR afterglow
DATE:    19/10/11 06:24:06 GMT
FROM:    Ana Nicuesa at TLS Tautenburg  <ana@tls-tautenburg.de>

A. Nicuesa Guelbenzu (TLS Tautenburg) and P. Schady (Univ. of Bath)
report:

We observed the field of GRB 191011A (Swift trigger 928924; Laha et al.,
GCN 25988) simultaneously in g'r'i'z'JHKs with GROND (Greiner et al. 2008,
PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La Silla
Observatory (Chile).

Observations started at 04:38 UT on 2019-10-11, around 2 minutes after the
GRB trigger and lasted for about 5 minutes. They were performed at an
average seeing of 1.14" and at an average airmass of 1.1.

We detect the optical afterglow candidate reported by Laha et al. (GCN
25988) and measure the following preliminary magnitudes and upper limits
(AB magnitudes):

r' = 19.52 +/- 0.1 mag,
i' = 18.46 +/- 0.05 mag,
z' = 18.62 +/- 0.1 mag,
J  = 17.89 +/- 0.1 mag,
H  = 17.21 +/- 0.1 mag.

The optical afterglow is also visible in g' band.

The magnitudes are calibrated against GROND zeropoints and 2MASS field
stars and are not corrected for the Galactic foreground extinction
corresponding to a reddening of E_(B-V)= 0.02 mag in the direction of the
burst (Schlegel et al. 1998).

We acknowledge the excellent support from Regis Lachaume in La Silla
in acquiring these observations.


GRB_name: GRB191011A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25993
SUBJECT: GRB 191011A: BALROG localization (Fermi Trigger 592461363 / GRB 191011192)
DATE:    19/10/11 06:29:51 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

J. Burgess, F. Kunzweiler, B. Biltzinger, F. Berlato,  & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
592461363 at 04:35:58 on 11 Oct. 2019 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 46.4+/-4.6 deg
Decl.(2000.0) = -32.5+/-5.6 deg
We estimate an additional systematic error of 2 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB191011192/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB191011192/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB191011192/json

                        


GRB_name: GRB191011A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25994
SUBJECT: GRB 191011A: correction of reported magnitudes
DATE:    19/10/11 08:09:21 GMT
FROM:    Ana Nicuesa at TLS Tautenburg  <ana@tls-tautenburg.de>

A. Nicuesa Guelbenzu (TLS Tautenburg) reports:

An error occurred in the previous data reduction. Corrected AB magnitudes
are (midtime of the observations: 04:42 UT, Oct. 11):

g' = 19.97 +/- 0.08 mag,
r' = 19.46 +/- 0.05 mag,
i' = 19.08 +/- 0.07 mag,
z' = 18.79 +/- 0.10 mag,
J  = 18.79 +/- 0.06 mag, and
H  = 18.61 +/- 0.06 mag,

calibrated against PanSTARRS and 2MASS field stars.


GRB_name: GRB191011A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25995
SUBJECT: GRB 191011A: Enhanced Swift-XRT position
DATE:    19/10/11 10:26:18 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 4075 s of XRT Photon Counting mode data and 7 UVOT
images for GRB 191011A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 44.72800, -27.84540 which is equivalent
to:

RA (J2000): 02h 58m 54.72s
Dec (J2000): -27d 50' 43.4"

with an uncertainty of 1.5 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB191011A
Detection_method: retraction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25996
SUBJECT: GRB 191011A: MASTER OT retraction.
DATE:    19/10/11 10:49:05 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov
Sternberg Astronomical Institute, Moscow State University

The GRB 191011A optical transient candidate  published by us in (Lipunov 
et. al. GCN 25989) is a group of hot pixels on a CCD matrix. This is not 
a real GRB afterglow candidate. We sorry for this mistake.


GRB_name: GRB191009A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25997
SUBJECT: GRB 191009A: Insight-HXMT/HE detection
DATE:    19/10/11 11:14:37 GMT
FROM:    QiBin Yi at IHEP, HXMT  <yiqb@ihep.ac.cn>

Q. B. Yi, S. Xiao, Q. Luo, C. Cai, C. K. Li,
X. B. Li, G. Li, J. Y. Liao, S. L. Xiong, 
C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, X. F. Lu,
A. M. Zhang, Y. F. Zhang, C. L. Zou (IHEP), Y. J. Jin, 
Z. Zhang (THU), T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, 
M. Wu, Y. P. Xu, S. N. Zhang (IHEP),
report on behalf of the Insight-HXMT team:

At 2019-10-09T07:08:56.77 (T0), Insight-HXMT/HE detected 
GRB 191009A (trigger ID: HEB191009297) in a routine search of the data, 
which was also triggered by Fermi/GBM (GCN #25985). 

The Insight-HXMT/HE light curve mainly consists of a single  
pulse with a duration (T90) of 17.76 s measured from T0-1.56 s. 
The 1-ms peak rate, measured from T0+7.40 s, is 495 cnts/sec. 
The total counts from this burst is 1769 counts. 
URL_LC: http://www.hxmt.org/images/GRB/HEB191009297_lc.jpg 

All measurements above are made with the CsI detectors operating in the 
regular mode with the energy range of about 80-800 keV (deposited energy). 
Only gamma-rays with energy greater than about 200 keV can penetrate 
the spacecraft and leave signals in the CsI detectors installed inside 
of the telescope. 

Insight-HXMT is the first Chinese space X-ray telescope, which was 
funded jointly by the China National Space Administration (CNSA) and 
the Chinese Academy of Sciences (CAS). 
More information about it could be found at: 
http://www.hxmt.org.


GRB_name: GRB191011A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25998
SUBJECT: GRB 191011A: Swift-XRT refined Analysis
DATE:    19/10/11 13:13:26 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore
(U. Leicester), M. Capalbi (INAF-IASFPA), M. Perri (ASDC), V. D'Elia
(ASDC), J.A. Kennea (PSU), B. Sbarufatti (PSU), D.N. Burrows (PSU) and
S.L Laha report on behalf of the Swift-XRT team:

We have analysed 7.1 ks of XRT data for GRB 191011A (L Laha et al. GCN
Circ. 25988), from 84 s to 23.3 ks after the  BAT trigger. The data are
entirely in Photon Counting (PC) mode. The enhanced XRT position for
this burst was given by Evans et al. (GCN Circ. 25995).

The light curve can be modelled with an initial power-law decay with an
index of alpha=0.15 (+0.15, -0.20), followed by a break at T+855 s to
an alpha of 1.34 (+/-0.12).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.83 (+/-0.15). The
best-fitting absorption column is  5.3 (+3.5, -3.1) x 10^21 cm^-2, at a
redshift of 1.722, in addition to the Galactic value of 1.5 x 10^20
cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed)
0.3-10 keV flux conversion factor deduced from this spectrum  is 3.6 x
10^-11 (4.1 x 10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Galactic foreground: 1.5 x 10^20 cm^-2
Intrinsic column:    5.3 (+3.5, -3.1) x 10^21 cm^-2 at z=1.722
Photon index:      1.83 (+/-0.15)

If the light curve continues to decay with a power-law decay index of
1.34, the count rate at T+24 hours will be 1.0 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.7 x
10^-14 (4.2 x 10^-14) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00928924.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB191011A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  25999
SUBJECT: GRB 19011A: Optical Afterglow Detection with LCO
DATE:    19/10/11 13:52:55 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:

We observed Fermi GRB 191011A (Fermi GBM Team at MSFC/Fermi-GBM, GCN 25987) with
the LCO 1-m Sinistro instrument at the Cerro Tololo site on October 11, from 04:54 to 05:18 UT
(corresponding to 0.13 to 0.4 hours from the GRB trigger time)
with the Bessel I filter.

We performed a series of 5x120s exposures.  While we do not detect a source in individual frames, we do detect a source in co-added frames that is not present in either USNO-B1.0 or 2MASS surveys that is consistent with the optical afterglow location (Palmer et al., GCN 25988) with the following magnitude:

I = 18.81 +/- 0.13

This flux is calibrated against several USNO-B1.0 objects near the GRB location but is not corrected for Galactic Extinction.

These observations were possible thanks to the USVI NASA-EPSCoR
Research Infrastructure Development (RID) grant NNX16AL44A.


GRB_name: GRB191011A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26000
SUBJECT: GRB 191011A: Fermi GBM observation
DATE:    19/10/11 14:23:34 GMT
FROM:    Peter Veres at UAH  <veresp@gmail.com>

E. Bissaldi (Politecnico and INFN Bari) and P. Veres (UAH)
report on behalf of the Fermi GBM Team:

"At 04:35:58.58 UT on 11 October 2019, the Fermi Gamma-Ray Burst Monitor
(GBM) triggered and located GRB 191011A (trigger 592461363 / 191011192), which
was also detected by the Swift/BAT (Laha et al. 2019, GCN 25988).

The GBM localization statistic exhibited two minima, one of which is
consistent with the Swift location (75% containment).  The localization
centroid in the Real-time Localization notice (GCN 25987) is for the other
minimum, which is near the Earth limb and is inconsistent with the Swift
location.

The angle from the Fermi LAT boresight at the GBM trigger time is 39
degrees.

The GBM light curve shows several pulses
with a duration (T90) of about 13 s (50-300 keV).
The time-averaged spectrum from T0-2.0 s to T0-0.38 s is
adequately fit by a simple power law function with index -1.76 +/- 0.08.

The event fluence (10-1000 keV) in this time interval is
(4.33 +/- 0.50)E-7 erg/cm^2. The 1-sec peak photon flux measured
starting from T0-1.8 s in the 10-1000 keV band is 3.29 +/- 0.30 ph/s/cm^2.

A power law function with an exponential high-energy cutoff
fits the spectrum equally well. The power law index is -1.24 +/- 0.29 and
the cutoff energy, parameterized as Epeak, is 89 +/- 23 keV.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support
Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB191011A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26001
SUBJECT: GRB 191011A: RATIR Optical and NIR Observations 
DATE:    19/10/11 15:41:42 GMT
FROM:    Alan M Watson at UNAM  <alan@astro.unam.mx>

Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC), William H.
Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier Prochaska
(UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI), Diego GonzÃ¡lez (UNAM),
Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), JesÃºs
GonzÃ¡lez (UNAM), Carlos RomÃ¡n-ZÃºÃ±iga (UNAM), Harvey Moseley (GSFC), John Capone
(UMD), V. Zach Golkhou (U. Wash.), and Vicki Toy (UMD) report:

We observed the field of GRB 191011A (Laha et al., GCN Circ. 25988) with the
Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m
Harold Johnson Telescope at the Observatorio AstronÃ³mico Nacional on Sierra San
Pedro MÃ¡rtir from 2019/10 11.26 to 2019/10 11.48 UTC (1.60 to 6.94 hours after
the BAT trigger), obtaining a total of 1.64 hours exposure in the i band and
0.49 hours exposure in the Z, Y, J, and H bands.

For a source within the Swift-XRT error circle, in comparison with the USNO-B1
and 2MASS catalogs, we obtain the following detections and upper limits
(3-sigma):

  i = 21.59 +/- 0.13
  Z = 21.22 +/- 0.21
  Y > 21.76
  J > 19.81
  H > 20.54

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

We thank the staff of the Observatorio AstronÃ³mico Nacional in San Pedro 
MÃ¡rtir.


GRB_name: GRB191011A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26002
SUBJECT: GRB 191011A: Swift/UVOT Detection
DATE:    19/10/11 17:23:17 GMT
FROM:    Paul Kuin at MSSL  <npkuin@gmail.com>

N. P. M. Kuin (UCL-MSSL) and Laha (GSFC/UMBC/CRESST)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 191011A
78 s after the BAT trigger (Laha et al., GCN Circ. 25988).  A source
consistent with the XRT position (Evans et al. GCN Circ. 25995)
is detected in the initial UVOT exposures. This GRB was also detected
by Fermi/GBM (GCN Circ. 25987,26000) and Insight-HXMT-HE(Yi et al, GCN
Cir. 25997). A redshift was reported using the VLT/Xshooter (Kahn et al,
GCN Circ.25991), while the optical afterglow was reported from Master
(Lipunov et al, GCN Circ. 25990; GROND (Nicuesa Guelbenzu et al.,
GCN Circ. 25992).

The preliminary UVOT position is:
    RA  (J2000) =  02:58:54.79 =  44.72829 (deg.)
    Dec (J2000) = -27:50:43.4  = -27.84540 (deg.)
with an estimated uncertainty of 0.73 arc sec. (radius, 90% confidence).

Preliminary detections and 3-sigma upper limits using the UVOT photometric
system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures
are:

Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

white               78          228          147         20.27 +/- 0.16
v                  620        11672         1211        >20.2
b                  545         7080          510         21.03 +/- 0.27
u                  290         6875          697         20.86 +/- 0.27
w1                 670         6670          510        >20.3
m2                1073        12198          767        >21.1
w2                1024         7491          432        >20.9

The afterglow is seen to be nearly constant in the white filter until
about 1000s, whereafter a decay is observed.  The magnitudes in the table
are
not corrected for the Galactic extinction due to the reddening of E(B-V) =
0.02
in the direction of the burst (Schlegel et al. 1998).


GRB_name: GRB191011A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26003
SUBJECT: GRB 191011A: Swift-BAT refined analysis
DATE:    19/10/12 01:36:12 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

T. N. Ukwatta (LANL), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), J. P. Norris (BSU),
D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU) (i.e. the Swift-BAT team):

Using the data set from T-239 to T+963 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 191011A (trigger #928924)
(Laha et al., GCN Circ. 25988).  The BAT ground-calculated position is
RA, Dec = 44.729, -27.853 deg which is
   RA(J2000)  =  02h 58m 55.0s
   Dec(J2000) = -27d 51' 12.4"
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 96%.

The mask-weighted light curve shows a short pulse that starts and peaks
at ~T0, and ends at ~T+2 s. The short pulse is followed by some weak
emission
that lasts until ~T+8 s. T90 (15-350 keV) is 7.37 +- 0.95 sec (estimated
error
including systematics).

The time-averaged spectrum from T-0.21 to T+8.04 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.94 +- 0.17.  The fluence in the 15-150 keV band is 3.3 +- 0.4 x 10^-7
erg/cm2.
The 1-sec peak photon flux measured from T+0.18 sec in the 15-150 keV band
is 1.8 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

Using the 16-ms binned light curve, the spectral lag of the short pulse
is 30 (+45, -34) ms for the 50-100 keV to 15-25 keV bands, and 20 (+40,
-44) ms
for the 25-50 keV to 15-25 keV bands. These values are consistent with
both short and long GRBs due to the large uncertainties.


The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/928924/BA/


GRB_name: GRB191009A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26004
SUBJECT: GRB 191009A: AstroSat CZTI detection
DATE:    19/10/12 05:31:46 GMT
FROM:    Ramkrishna Gaikwad at IUCAA/AstroSat  <ramkrishna@iucaa.in>

R. Gaikwad, V. Sharma and D. Bhattacharya (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data showed the detection of a GRB 191009A, which was also detected by Fermi GBM Final Real-time Localization (GCN #25985), BALROG localization (Biltzinger B. et al., GCN # 25986) and Insight-HXMT/HE (Luo Q. et al., GCN # 25997).

The source was clearly detected in the 40-200 keV energy range. The light curve shows multiple pulses of emission with the strongest peak at 2019-10-09 07:08:56.0 UT. The measured peak count rate associated with the burst is 572 cts/s above the background in the combined data of four quadrants, with a total of 1682 cts. The local mean background count rate was 473 cts/s. Using cumulative rates, we measure a T90 of 22.0 s. 

It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.

CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.


GRB_name: GRB191016A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26008
SUBJECT: GRB 191016A: Swift detection of a burst
DATE:    19/10/16 04:25:46 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

J.D. Gropp (PSU), N. J. Klingler (PSU), A. Y. Lien (GSFC/UMBC),
M. J. Moss (GWU), D. M. Palmer (LANL) and B. Sbarufatti (PSU) report
on behalf of the Neil Gehrels Swift Observatory Team:

At 04:09:00 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 191016A (trigger=929744).  Swift did not immediately
slew due to an observing constraint. 
The BAT on-board calculated location is 
RA, Dec 30.296, +24.501 which is 
   RA(J2000) = 02h 01m 11s
   Dec(J2000) = +24d 30' 03"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a complex structure
structure with a duration of at least 200 sec.  The peak count rate
was ~1500 counts/sec (15-350 keV), at ~-6 sec after the trigger. 

Due to a Moon observing constraint, Swift cannot slew to the BAT
position until 15:17 UT on 2019 October 16. There will thus be no XRT
or UVOT data for this trigger before this time. 

This source lies within the current (Sector 17) field-of-view of TESS camera 1. 

Burst Advocate for this burst is J.D. Gropp (jdg44 AT psu.edu). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB191016A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26010
SUBJECT: GRB 191016A: COATLI Optical Observations and Detection of the Afterglow
DATE:    19/10/16 05:03:38 GMT
FROM:    Alan M Watson at UNAM  <alan@astro.unam.mx>

Alan M. Watson (UNAM),  Nat Butler (ASU), Rosa L. Becerra (UNAM), Diego GonzÃ¡lez
(UNAM), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Margarita Pereyra
(UNAM), and Eleonora Troja (GSFC) report:

Alan M. Watson (UNAM),  Nat Butler (ASU), Rosa L. Becerra (UNAM), Diego GonzÃ¡lez
(UNAM), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Margarita Pereyra
(UNAM), and Eleonora Troja (GSFC) report:

We observed the field of GRB 191016A (Gropp et al., GCN Circ. Gropp) with the
COATLI 50-cm telescope and interim imager at the Observatorio AstronÃ³mico
Nacional on the Sierra de San Pedro MÃ¡rtir (http://coatli.astroscu.unam.mx) from
2019-10-16 04:40:19 (378.7 seconds after the trigger and 21.8 seconds after the
alert) to 04:49, obtaining a total of 1200 seconds of exposure in the w filter.

We detect a bright uncataloged source at 02:01:04.75 +24:30:36.8 J2000 (+/- 0.5
arcsec), about 91 arcsec from the BAT position. The source rises from w = 16.5
to w = 15.0 before fading. We suggest this is the afterglow.

Our w magnitudes are calibrated against the Pan-STARRS1 catalog, are on an
approximate AB system (Becerra et al., 2019, ApJ, 872, 118), and are not
corrected for Galactic extinction in the direction of the GRB.

Observations are continuing.

We thank the COATLI technical team and the staff of the Observatorio AstronÃ³mico
Nacional.


GRB_name: GRB191016A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26011
SUBJECT: GRB 191016A: KAIT Optical Afterglow Confirmation
DATE:    19/10/16 19:32:11 GMT
FROM:    Weikang Zheng at UC Berkeley  <weikang@berkeley.edu>

WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on
behalf of the KAIT GRB team:

The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, responded to the Swift GRB 191016A (Gropp et al.,
GCN 26008) starting at ~1.6 hours after the burst. We obtained
33x60s images in the clear (roughly R) filter. We detect and thus
confirm the optical afterglow at the position reported by Watson et al.
(GCN 26010) in our co-added image. Due to a strong moon light gradient
in our images, we are unable to measure a reliable magnitude of the
target. We estimate the afterglow is between 16.5 to 17.5 mag at a
mid-time of ~2.0 hours after the burst.


GRB_name: GRB191016A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26012
SUBJECT: GRB 191016A: Swift-BAT refined analysis
DATE:    19/10/16 21:40:40 GMT
FROM:    Sibasish Laha at GSFC  <sibasish.laha@nasa.gov>

S. D. Barthelmy (GSFC), J. R. Cummings (CPI),
J.D. Gropp (PSU), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Sakamoto (AGU), M. Stamatikos (OSU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-240 to T+962 sec from the recent telemetry
 downlink, we report further analysis of BAT GRB 191016A (trigger #929744)
(Gropp et al., GCN Circ. 26008).  The BAT ground-calculated position is
RA, Dec = 30.268, 24.508 deg which is
   RA(J2000)  =  02h 01m 04.4s
   Dec(J2000) = +24d 30' 30.4"
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 64%.

The mask weighted light curve shows two overlapping pulses.
Overall structure starts at ~ T-40 s and lasts till ~ T+420 s.
The two peaks occur at ~ T-10 s and ~ T+35 s, respectively.
T90 (15-350 keV) is 219.70 +- 183.35 sec (estimated error including systematics).

The time-averaged spectrum from T-42.82 to T+422.61 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.55 +- 0.09.  The fluence in the 15-150 keV band is 6.5 +- 0.4 x 10^-06 erg/cm2.
The 1-sec peak photon flux measured from T-7.75 sec in the 15-150 keV band
is 1.5 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/929744/BA/


GRB_name: GRB191016A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26013
SUBJECT: GRB 191016A: Optical limit by Ondrejov D50
DATE:    19/10/16 21:55:29 GMT
FROM:    Martin Jelinek at Astro.Inst-AVCR,Ondrejov  <martin.jelinek@asu.cas.cz>

Martin Jelinek and Jan Strobl (ASU CAS Ondrejov, CZ)
report:

We observed GRB 191016A (Gropp et al. GCNC 26008) with the 50 cm robotic
telescope (D50) of Ondrejov observatory in the Czech Republic, obtaining a
series of 120s images starting at 17:55UT, i.e. 13.6h post trigger.

We do not detect the optical afterglow (Watson, GCNC 26010; Zheng et al.,
GCNC 26011 and others) in a combined 60x120s I-band image with exposure
mean time 14.6h after the GRB. A rough conservative detection limit of the
image is I(Vega) > 19.5; as mentioned before by Zheng et al., the proximity
of Moon makes any photometric measurement difficult.


GRB_name: GRB191016A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26015
SUBJECT: GRB 191016A: RATIR Optical and NIR Observations 
DATE:    19/10/17 01:31:15 GMT
FROM:    Alan M Watson at UNAM  <alan@astro.unam.mx>

Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC), William H.
Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier Prochaska
(UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI), Eleonora Troja (GSFC), Owen
Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), JesÃºs GonzÃ¡lez (UNAM), Carlos
RomÃ¡n-ZÃºÃ±iga (UNAM), Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou
(U. Wash.), and Vicki Toy (UMD) report:

We observed the field of GRB 191016A (Gropp et al., GCN Circ. 26008) with the
Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m
Harold Johnson Telescope at the Observatorio AstronÃ³mico Nacional on Sierra San
Pedro MÃ¡rtir from 2019/10 16.18 to 2019/10 16.26 UTC (0.12 to 2.13 hours after
the BAT trigger), obtaining a total of 0.99 hours exposure in the r and i bands
and 0.54 hours exposure in the Z, Y, J, and H bands.

We detect a source coincident with the COATLI afterglow candidate (Watson et
al., GCN Circ. 26010). In comparison with the SDSS DR9 and 2MASS catalogs, we
obtain the following detections:

  r = 16.42 +/- 0.00
  i = 16.16 +/- 0.00
  Z = 15.91 +/- 0.01
  Y = 15.78 +/- 0.01
  J = 15.42 +/- 0.01
  H = 15.10 +/- 0.01

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

The light curve shows similar behaviour to that reported by Watson et al. We see
the source rise from r = 16.8 to r = 15.3 before falling to r = 17 at the end of
these observations.

In subsequent observations we added images in the g filter and determined that
the g - r color is 0.44 +/- 0.01. This strongly suggests that the GRB is at z <
4 (Littlejohns et al. 2014).

We thank the staff of the Observatorio AstronÃ³mico Nacional in San Pedro MÃ¡rtir.


GRB_name: GRB191016A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26017
SUBJECT: GRB 191016A: early time BOOTES Network and follow-up 1.5m OSN optical observations
DATE:    19/10/17 09:58:20 GMT
FROM:    Alberto J. Castro-Tirado at IAA-CSIC  <ajct@iaa.es>

Y.-D. Hu, E. Fernandez-Garcia, A. J. Castro-Tirado, I. Olivares, F. 
Rendon, A. Sota (IAA-CSIC), C. Perez del Pulgar, A. Castellon, I. M. 
Carrasco, S. Castillo (Univ. de Malaga), D. Hiriart, W. H. Lee (UNAM), 
I. H. Park (SKKU) and M. D. Caballero-Garcia (ASU-CAS, CZ) on behalf of 
a larger collaboration, report:

Following the detection of GRB 191016A by Swift (Gropp et al., GCNC 
26008), the BOOTES Network robotic telescopes automatically responded to 
this burst at the different astronomical stations worlwide.

The 60cm BOOTES-5/JGT robotic telescope at Observatorio Astronomico 
Nacional in San Pedro Martir (Mexico) gathered images (clear-filter) 
starting at 04:15:06U T (6.0 min after the GRB onset).

The 60cm BOOTES-2/TELMA robotic telescope at IHSM La Mayora (UMA-CSIC) 
in Algarrobo Costa (Spain) obtained images (i-band filter) starting at 
04:15:15 UT (6.3 min after the GRB onset).

The 30cm BOOTES-1B robotic telescope at INTA-CEDEA in Mazagon (Huelva), 
southern Spain, imaged the field (clear filter) starting at 04:16:32 UT 
(7.5 min after the GRB onset).

The optical afterglow (Watson et al. GCNC 26010, Zheng et al. GCNC 
26011, Watson et al. GCNC 26015) is detected in all three BOOTES 
stations. Detailed data analysis is ongoing.

Follow-up observations were also triggered at the 1.5m OSN telescope in 
Observatorio de Sierra Nevada, Granada (Spain) starting at 19:56 UT 
(15.8 h after the GRB trigger). The afterglow was still detected in the 
R-band, for which we measure R = 19.8 +/- 0.1 (preliminary).

We thank the staff at Observatorio Astronomico Nacional in San Pedro 
Martir, IHSM La Mayora, INTA-CEDEA and Observatorio de Sierra Nevada for 
the excellent support.


GRB_name: GRB191016A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26018
SUBJECT: GRB 191016A: AZT-20 (Assy observatory) optical photometry
DATE:    19/10/17 10:18:43 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

V. Kim (AFIF, Pulkovo Observatory) A. Pozanenko (IKI), M. Krugov (AFIF), 
  I. Reva (AFIF), E. Mazaeva  (IKI), A. Volnova (IKI) report on behalf 
of larger GRB IKI FuN collaboration:

We observed the field of the  GRB 191016A   (Gropp al., GCN  26008) with 
AZT-20 telescope  of Assy-Turgen observatory (MPC observatory code 217) 
starting on Oct. 16  (UT) 14:58:49  in  r'-filter.    We clearly detect 
the optical afterglow (Watson al., GCN  26010; Zheng al., GCN  26011; 
Watson  al., GCN  26015; Hu et al., GCN 26017).
Preliminary photometry of the afterglow is following.

Date       UT start   t-T0       Filter Exp.   OT   Err.
                       (mid, days)        (s)

2019-10-16 14:58:49   0.48336     r'    120*30 20.6 0.15

The photometry is based on the nearby USNO-B1  stars and BRI 
transformations to r'.

The photometry in agreement with non detection of the optical afterglow 
by Jelinek et al. (GRB 26013).


GRB_name: GRB191016A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26019
SUBJECT: GRB191016A: MITSuME Okayama optical observation
DATE:    19/10/17 11:15:15 GMT
FROM:    Sayaka Toma at Tokyo Institute of Technology  <toma@hp.phys.titech.ac.jp>

S. Toma, M. Niwano, R. Adachi, K. L. Murata,  M. Oeda, K.Shiraishi, K. Iida,
F. Ogawa, R. Hosokawa, Y. Yatsu, and N. Kawai (TokyoTech)
report on behalf of the MITSuME collaboration:


We searched for the optical counterpart of GRB 191016A (J.D. Gropp et
al., GCN Circular #26008) with the optical three color (g', Rc, and
Ic) CCD cameras
attached to the MITSuME 50 cm telescope of Okayama
Astrophysical Observatory, Okayama, Japan.

The observation started on 09:37:49.50 UT which corresponds to
5.5 hours after the trigger.
We detected the point source at the position consistent with the
afterglow detected previously (Alan M. Watson et al. GCN #26010).
The measured magnitudes and 3-sigma limit are listed as follows.

T0+[sec]    MID-UT      T-EXP[sec]        g'       Rc        Ic
â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”â€”
20794      13:31:46          20040              19.5+/-0.4
> 19.0     18.6+/-0.2
-------------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used GSC2.3 and UCAC4 catalog for flux calibration.
The magnitudes are expressed in the Vega system.


GRB_name: GRB191017A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26020
SUBJECT: GRB 191017A: Fermi GBM Final Localization
DATE:    19/10/17 14:22:00 GMT
FROM:    Rachel Hamburg at UAH  <rkh0007@uah.edu>

R. Hamburg (UAH) reports on behalf of the Fermi GBM Team:

The Fermi Gamma-ray Burst Monitor (GBM) trigger (trigger 592997024 /
191017391)
at 09:23:39.27 UT on 17 October, 2019, was misclassified by the GBM flight
software as a particle event but is in fact due to a GRB.

Therefore, the Fermi GBM team reports the detection of GRB 191017A. The
on-ground calculated location, using the Fermi GBM trigger data, is
RA = 171.25, Dec = +38.05 (J2000 degrees, equivalent to J2000 11h 25m, 38d
03'),
with a statistical uncertainty of 1.5 degrees. The angle from the Fermi LAT
boresight is 131.44 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191017391/quicklook/glg_skymap_all_bn191017391.png

The HEALPix FITS file, including the estimated localization systematic, can
be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191017391/quicklook/glg_healpix_all_bn191017391.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191017391/quicklook/glg_lc_medres34_bn191017391.gif


GRB_name: GRB191017B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26021
SUBJECT: GRB 191017B: Swift detection of a burst
DATE:    19/10/17 14:55:44 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

B. Sbarufatti (PSU), J.D. Gropp (PSU), J. A. Kennea (PSU),
N. J. Klingler (PSU), A. Y. Lien (GSFC/UMBC), M. J. Moss (GWU),
K. L. Page (U Leicester), D. M. Palmer (LANL) and
A. Tohuvavohu (Toronto) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 14:36:06 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 191017B (trigger=929981).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 245.151, -73.561 which is 
   RA(J2000) = 16h 20m 36s
   Dec(J2000) = -73d 33' 40"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single-peaked
structure with a duration of about 8 sec.  The peak count rate
was ~1000 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 14:37:50.7 UT, 103.8 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source with an enhanced position: RA, Dec 245.1255, -73.5404
which is equivalent to:
   RA(J2000)  = 16h 20m 30.13s
   Dec(J2000) = -73d 32' 25.3"
with an uncertainty of 2.2 arcseconds (radius, 90% containment). This
location is 78 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (9.84 x
10^20 cm^-2, Willingale et al. 2013), with an excess column of 3
(+3.00/-2.59) x 10^21 cm^-2 (90% confidence). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 301 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.11. 

Burst Advocate for this burst is B. Sbarufatti (bxs60 AT psu.edu). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB191017B
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26022
SUBJECT: GRB 191017B: Enhanced Swift-XRT position
DATE:    19/10/17 20:12:56 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 759 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 191017B, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 245.12493, -73.54074 which is equivalent
to:

RA (J2000): 16h 20m 29.98s
Dec (J2000): -73d 32' 26.7"

with an uncertainty of 1.8 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB191017C
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26023
SUBJECT: GRB 191017C: Fermi GBM Final Real-time Localization
DATE:    19/10/17 23:08:45 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 22:58:20 UT on 17 Oct 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 191017C (trigger 593045905.586428 / 191017957).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 134.6, Dec = 15.3 (J2000 degrees, equivalent to J2000 08h 58m, 15d 18'), with a statistical uncertainty of 12.4 degrees.

The angle from the Fermi LAT boresight is 69.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191017957/quicklook/glg_skymap_all_bn191017957.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191017957/quicklook/glg_healpix_all_bn191017957.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191017957/quicklook/glg_lc_medres34_bn191017957.gif


GRB_name: GRB191016A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26024
SUBJECT: GRB 191016A: Swift/UVOT Detection
DATE:    19/10/17 23:13:53 GMT
FROM:    Mike Siegel at PSU/Swift MOC  <mhs18@psu.edu>

M. H. Siegel and J. D. Gropp (PSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 191016A
45 ks after the BAT trigger (Gropp et al., GCN Circ. 26008).  A 
source is detected consistent with the XRT position and the optical source reported
by Watson et al. (GCN Circ. 26010, 26015), Zheng and Filippenko (GCN Circ. 26011),
Hu et al. (GCN Circ. 26017), Kim et al. (GCN Circ. 26018) and Toma et al.
(GCN Circ. 26019).

The preliminary UVOT position is:
    RA  (J2000) =  02:01:04.68 =  30.26948 (deg.)
    Dec (J2000) = +24:30:35.7  =  24.50990 (deg.)
with an estimated uncertainty of 0.5 arc sec. (radius, 90% confidence).

Preliminary detections and 3-sigma upper limit using the UVOT photometric
system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures
are:

Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

white            45023        46878         1822        21.09+/-0.17
white            50812        52638         1794        21.21+/-0.19
white            56420        56938          506        >21.23

The magnitudes in the table are not corrected for the Galactic extinction due
to the reddening of E(B-V) = 0.09 in the direction of the burst (Schlegel et al. 1998).


GRB_name: GRB191016A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26026
SUBJECT: GRB 191016A: Swift-XRT afterglow detection
DATE:    19/10/18 00:12:22 GMT
FROM:    Boris Sbarufatti at PSU  <bxs60@psu.edu>

K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), M. Perri
(ASDC), V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), B. Sbarufatti (PSU),
D.N. Burrows (PSU), J. D. Gropp (PSU) and P.A. Evans (U. Leicester)
report on behalf of the Swift-XRT team:

Swift-XRT has performed follow-up observations of the
Swift/BAT-detected burst GRB 191016A (WeiKang Zheng et al. GCN Circ.
26012), collecting 4.2 ks of Photon Counting (PC) mode data between
T0+45.0 ks and T0+56.9 ks. 

An uncatalogued X-ray source is detected consistent with being within
296 arcsec of the Swift/BAT position and is above the RASS limit, and
is therefore likely the GRB afterglow. Using 3470 s of PC mode data and
3 UVOT images, we find an enhanced XRT position (using the XRT-UVOT
alignment and matching UVOT field sources to the USNO-B1 catalogue):
RA, Dec = 30.26933, +24.50988 which is equivalent to:

RA (J2000): 02h 01m 04.64s
Dec(J2000): +24d 30' 35.6"

with an uncertainty of 1.9 arcsec (radius, 90% confidence). This
position is 93 arcsec from the Swift/BAT position. 

The light curve can be modelled with a power-law decay with a decay
index of alpha=1.8 (+1.5, -0.5).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.9 (+0.5, -0.4). The
best-fitting absorption column is  1.4 (+1.7, -0.4) x 10^21 cm^-2,
consistent with the Galactic value of 1.0 x 10^21 cm^-2 (Willingale et
al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux
conversion factor deduced from this spectrum  is 3.4 x 10^-11 (4.3 x
10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      1.4 (+1.7, -0.4) x 10^21 cm^-2
Galactic foreground: 1.0 x 10^21 cm^-2
Excess significance: <1.6 sigma
Photon index:      1.9 (+0.5, -0.4)

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00929744.
The results of the full analysis of the XRT observations are available
at https://www.swift.ac.uk/ToO_GRBs/00929744.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB191017B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26027
SUBJECT: GRB 191017B: Swift-XRT refined Analysis
DATE:    19/10/18 05:32:16 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

A.P. Beardmore (U. Leicester), V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA),
A. Melandri (INAF-OAB), D.N. Burrows (PSU), J. D. Gropp (PSU), A.
Tohuvavohu (U. Toronto), P.A. Evans (U. Leicester), J.P. Osborne (U.
Leicester) and B. Sbarufatti report on behalf of the Swift-XRT team:

We have analysed 6.1 ks of XRT data for GRB 191017B (Sbarufatti et al.
GCN Circ. 26021), from 256 s to 29.2 ks after the  BAT trigger. The
data are entirely in Photon Counting (PC) mode. The enhanced XRT
position for this burst was given by Goad et al. (GCN Circ. 26022).

The light curve can be modelled with a power-law decay with a decay
index of alpha=0.64 (+/-0.05).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.54 (+0.20, -0.12). The
best-fitting absorption column is  consistent with the Galactic value
of 9.8 x 10^20 cm^-2 (Willingale et al. 2013). The counts to observed
(unabsorbed) 0.3-10 keV flux conversion factor deduced from this
spectrum  is 4.4 x 10^-11 (4.9 x 10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      9.8 (+/-6.9) x 10^20 cm^-2
Galactic foreground: 9.8 x 10^20 cm^-2
Excess significance: <1.6 sigma
Photon index:      1.54 (+0.20, -0.12)

If the light curve continues to decay with a power-law decay index of
0.64, the count rate at T+24 hours will be 0.018 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 7.8 x
10^-13 (8.6 x 10^-13) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00929981.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB191016A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26028
SUBJECT: GRB 191016A: REM optical observations
DATE:    19/10/18 13:44:05 GMT
FROM:    Andrea Melandri at INAF-OAB  <andrea.melandri@inaf.it>

A. Melandri, S.Covino, D. Fugazza, P. Dâ€™Avanzo (INAF/OAB), on behalf of the REM team, report:


We observed the field of GRB191016A (Gropp et al. GCN 26008) with the REM 60cm robotic telescope located at the ESO premise of La Silla (Chile). The observations were performed starting from about 6 min after the event and were carried in the g, r, i, z bands. 

The optical counterpart (Watson et al. GCN 26010; Zheng & Filippenko GCN 26011; Watson et al. GCN 26015; Hu et al. GCN 26017; Kim et al. 26018; Toma et al. GCN 26019; Siegel & Gropp GCN 26024) is detected in the optical bands. A preliminary photometry gives:

r = 16.1 +- 0.2 at 13 min from the GRB time.

Magnitudes are calibrated against the APASS catalogue.


GRB_name: GRB191017B
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26029
SUBJECT: GRB 191017B: Swift/UVOT Upper Limits
DATE:    19/10/18 14:37:28 GMT
FROM:    Sam LaPorte at PSU  <sjl5346@psu.edu>

GRB 191017B: Swift/UVOT Upper Limits

J. D. Gropp (PSU) and B. Sbarufatti (PSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 191017B
302 s after the BAT trigger (Sbarufatti et al., GCN Circ. 26021).
No optical afterglow consistent with the XRT position
(Goad et al. GCN Circ. 26022)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC           302          452          147         >18.9
white              302         1010          334         >19.1
v                  460         4806          255         >18.1
b                  558          752           39         >18.3
u                  533          727           39         >18.9
w1                 509          702           39         >18.2
m2                 484          852           39         >18.6
w2                 609         4601          235         >20.0

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.11 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB191017B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26030
SUBJECT: GRB 191017B: Swift-BAT refined analysis
DATE:    19/10/18 23:37:15 GMT
FROM:    Sibasish Laha at GSFC  <sibasish.laha@nasa.gov>

J. R. Cummings (CPI), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Sakamoto (AGU), B. Sbarufatti (PSU),
M. Stamatikos (OSU), T. N. Ukwatta (LANL),
S. D. Barthelmy (GSFC), (i.e. the Swift-BAT team):

Using the data set from T-82 to T+962 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 191017B (trigger #929981)
(Sbarufatti et al., GCN Circ. 26021).  The BAT ground-calculated position is
RA, Dec = 245.131, -73.583 deg which is
   RA(J2000)  =  16h 20m 31.3s
   Dec(J2000) = -73d 34' 57.7"
with an uncertainty of 1.8 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 44%.

The mask weighted light curve shows a single peak structure with a duration of ~8 sec.
The overall structure starts at ~ T-2 sec and lasts till ~ T+6 sec.
T90 (15-350 keV) is 5.95 +- 1.28 sec (estimated error including systematics).

The time-averaged spectrum from T-1.34 to T+5.59 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.82 +- 0.20.  The fluence in the 15-150 keV band is 5.6 +- 0.7 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+0.36 sec in the 15-150 keV band
is 1.9 +- 0.3 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/929981/BA/


GRB_name: GRB191019A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26031
SUBJECT: GRB 191019A: Swift detection of a burst
DATE:    19/10/19 15:21:47 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

K. K. Simpson (PSU), S. D. Barthelmy (GSFC), J.D. Gropp (PSU),
A. Y. Lien (GSFC/UMBC), K. L. Page (U Leicester), D. M. Palmer (LANL)
and A. Tohuvavohu (Toronto) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 15:12:33 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 191019A (trigger=930285).  Swift did not slew due to an observing
constraint.  The BAT on-board calculated location is 
RA, Dec 340.038, -17.333, which is 
   RA(J2000)  =  22h 40m 09s
   Dec(J2000) = -17d 19' 59"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows multiple peaks in a FRED
envelope with a total duration of about 80 sec.  The peak count rate
was ~4500 counts/sec (15-350 keV), at ~4 sec after the trigger. 

Due to an observing constraint, Swift will not slew until T0+51.6
minutes. There will be no XRT or UVOT data until this time. 

Burst Advocate for this burst is K. K. Simpson (kira.simpson1984 AT gmail.com). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB191019A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26032
SUBJECT: GRB 191019A: MASTER optical observation
DATE:    19/10/19 15:46:07 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, N.Tiurina, E. Gorbovskoy, V.Kornilov, F.Balakin,P.Balanutsa,A.Kuznetsov, V.Vladimirov, D. Vlasenko, I.Gorbunov,
D.Zimnukhov,V.Senik, T.Pogrosheva, K.Pozdnyakov,A.Chasovnikov, V.Topolev, D.Kuvshinov(Lomonosov Moscow State University, SAI,Physics Department),
R. Podesta, C.Lopez, F. Podesta, C.Francile(Observatorio Astronomico FelixAguilar OAFA),
H.Levato(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),
R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias),
D. Buckley(South African Astronomical Observatory),
O.A. Gres, N.M. Budnev, O.Ershova(Irkutsk State University, API),
A. Tlatov, D. Dormidontov(Kislovodsk Solar Station of the Pulkovo Observatory),
V. Yurkov, A. Gabovich, Yu. Sergienko(Blagoveschensk Educational StateUniversity)


MASTER-Kislovodsk robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, v.2010, 30L)
started Swift GRB191019A (Simpson et al. GCN26031 , BAT, RA,Dec= RA(J2000)  =  22h 40m 09s, -17d 19' 59")
observations at  2019-10-19 15:13:14Ut with exp. 10s, but sun altitude=-10.
The first image with mlim=15.0 made at 2019-10-19 15:23:59UT.

Real time updated cover map and possibly OT, that can be discovered, 
will be available here:
https://master.sai.msu.ru/site/master2/event.php?id=1171578


The observation and reduction will be continued.
The message may be cited.


GRB_name: GRB191019A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26034
SUBJECT: GRB 191019A: Swift-XRT observations
DATE:    19/10/19 16:22:58 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester), D.N. Burrows
(PSU), J.A. Kennea (PSU), S. Campana (INAF-OAB) and G. Cusumano
(INAF-IASF PA) report on behalf of the Swift-XRT team:

The XRT began observing the field of GRB 191019A at 16:06:04.5 UT,
3210.9 seconds after the BAT trigger. Using promptly downlinked data we
find an uncatalogued X-ray source with an enhanced position: RA, Dec
340.0244, -17.3286 which is equivalent to:
   RA(J2000)  = 22h 40m 05.86s
   Dec(J2000) = -17d 19' 42.9"
with an uncertainty of 3.1 arcseconds (radius, 90% containment). This
location is 49 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper.  We
cannot determine whether the source is fading at the present time. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (3.28 x
10^20 cm^-2, Willingale et al. 2013), with an excess column of 3.5
(+2.44/-3.29) x 10^22 cm^-2 (90% confidence). 


GRB_name: GRB191019A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26036
SUBJECT: GRB 191019A: TSHAO optical observations, probable afterglow and host galaxy
DATE:    19/10/19 18:55:20 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

I. Reva (FAPHI), A. Pozanenko (IKI), M. Krugov (FAPHI), S. Belkin (IKI), 
  E. Mazaeva (IKI), A. Volnova (IKI) report on behalf of IKI-GRB-FuN:

We observed the field of GRB 191019A (Simpson  et al.  GCN 26031) with 
Zeiss-1000 1-m telescope of Tien Shan Astronomical Observatory starting 
on Oct. 19 (UT) 15:26:32, i.e. 14 minutes after GRB trigger.   Within 
XRT error circle (Evans et al., GCN 26034) we found only one source 
which is presented in catalogs.   Preliminary photometry of the source 
is following.

Date       UT start t-T0    Filter  Exp. OT    Err.
                     (mid, days)     (s)

2019-10-19 15:26:32 0.013877  R     720 18.37  0.03

The photometry is based nearby USNO-B1.0 stars.

The brightness of the catalogued source is R2(USNO-B1.0 340.024514480) = 
19.36 and r'(Pan-STARRS 0726-1153339) = 19.30. The source is probably a 
host galaxy of  GRB 191019A and we suggest the afterglow of the source 
on a top of the host galaxy.


GRB_name: GRB191019A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26039
SUBJECT: GRB 191019A: NOT optical observations
DATE:    19/10/19 21:30:22 GMT
FROM:    Daniel Perley at Liverpool JMU  <d.a.perley@ljmu.ac.uk>

D. A. Perley (LJMU), D. B. Malesani (DTU Space), A. de Ugarte Postigo 
(HETH, IAA/CSIC; DARK/NBI), D. Xu (NAO/CAS), J. P. U. Fynbo (DAWN/NBI), 
K. E. Heintz (Univ. Iceland), and N. E. Jannsen (NOT) report on behalf 
of a larger collaboration:

We observed the field of GRB 191019A (Simpson et al., GCN 26031) with 
the Nordic Optical Telescope (NOT) equipped with the ALFOSC imaging 
camera. Observations started on 2019 Oct 19.822 UT (4.52 hr after the 
trigger).

In a single 120 s image taken in the SDSS i band, we detect the object 
mentioned by Reva et al. (GCN 26036), which is also visible in the 
Pan-STARRS archival images and is consistent with the X-ray position 
(Evans et al., GCN 26034). The target is clearly extended (FWHM 1.4" 
with a seeing of 1.1").

The object centroid has coordinates (J2000, calibrated against the Gaia 
catalog):

RA  =  22:40:05.89
Dec = -17:19:42.7

Measuring its magnitude over an aperture of 1.7" radius, we obtain i = 
18.66 +/- 0.01 AB (statistical error), compared to i = 18.71 +/- 0.01 
from the Pan-STARRS catalog (Chambers et al. 2015, arXiv:1612.05560), 
confirmed by our own measurement on the i-band Pan-STARRS image. The 
small flux difference may be due to calibration, color effects, or 
variable aperture correction, so we do not claim any afterglow 
detection.  A conservative limit on the afterglow magnitude at the time 
of our observation would be i > 21.

We note the elevated column density measured in a preliminary analysis 
of the X-ray spectra (Evans et al., GCN 26034). This may suggest a 
dust-obscured event.









DisclaimerNone


GRB_name: GRB191019B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26040
SUBJECT: GRB 191019B: Fermi GBM Final Real-time Localization
DATE:    19/10/19 23:27:25 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 23:17:13 UT on 19 Oct 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 191019B (trigger 593219838.347392 / 191019970).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 216.3, Dec = -40.6 (J2000 degrees, equivalent to J2000 14h 25m, -40d 36'), with a statistical uncertainty of 1.0 degrees.

The angle from the Fermi LAT boresight is 82.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191019970/quicklook/glg_skymap_all_bn191019970.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191019970/quicklook/glg_healpix_all_bn191019970.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191019970/quicklook/glg_lc_medres34_bn191019970.gif


GRB_name: GRB191019A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26041
SUBJECT: GRB 191019A: NOT optical spectroscopy of candidate counterpart
DATE:    19/10/19 23:47:11 GMT
FROM:    Daniele B Malesani at DTU Space  <malesani@space.dtu.dk>

J. P. U. Fynbo (DAWN/NBI), D. A. Perley (LJMU), A. de Ugarte Postigo 
(HETH/IAA-CSIC; DARK/NBI), D. B. Malesani (DTU Space), N. E. Jannsen 
(NOT), report on behalf of a larger collaboration:

Spectroscopy was secured of the optical counterpart (Reva et al., GCN 
26036; Perley et al., GCN 26039) of GRB 191019A (Simpson et al., GCN 
26031), using the ALFOSC instrument mounted on the Nordic Optical 
Telescope (NOT). Observations started on 2019 Oct 19.873 UT (5.74 hr 
after the GRB), for a total of 2x1800 s exposure.

Our spectrum, secured with grism #4, covers the approximate wavelength 
range 3500-9400 AA. The continuum is well detected. No prominent 
emission lines are visible. However, several absorption features can be 
identified, including Ca H & K, Na I D, Hdelta, Hgamma, Hbeta, G band, 
all at a common redshift z = 0.248. The 4000 AA break is also present.

The spectrum is typical of an old stellar population, and is unlike that 
of long-duration GRB host galaxies. The association of this object with 
GRB 191019A is therefore unclear.

Using the formula by Bloom et al. (2002, AJ, 123, 1111), the chance 
association probability for a source with magnitude r = 19.14 AB (from 
the Pan-STARRS catalog) and an error circle radius of 3.1" (Evans et 
al., GCN 26034) is approximately 3*10^-3.


GRB_name: GRB191019A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26042
SUBJECT: GRB 191019A: GROND observations
DATE:    19/10/20 13:43:49 GMT
FROM:    Ana Nicuesa at TLS Tautenburg  <ana@tls-tautenburg.de>

A. Nicuesa Guelbenzu (TLS Tautenburg) reports:

GROND (Greiner et al. 2008, PASP 120, 405) performed a first visit of
the field of GRB 191019A (Swift trigger 930285; Simpson et al., GCN 26031)
at 01:35 UT on 2019-10-20, about 10.3 hours after the burst.
Observations were performed at an airmass of 1.02 and a seeing of 2.0
arcsec. Second-epoch observations started at 05:10 UT on the same night
(airmass 1.75, seeing 1.7 arcsec).

The potential afterglow plus host-galaxy complex is clearly detected.
Between the 1st and the 2nd-epoch observations there is  no evidence for
fading in any band (g'r'i'z' as well as in JHKs). The GROND
r'(AB = 19.14 +/- 0.01) and i' (AB = 18.73 +/- 0.01) magnitudes are in
agreement with the NOT observations and the Pan-STARRS catalog (Perley et
al., GCN 26039; Fynbo et al., GCN 26041).

I acknowledge the excellent support from Sam Kim on La Silla in acquiring
these observations


GRB_name: GRB191019A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26043
SUBJECT: GRB 191019A: Enhanced Swift-XRT position
DATE:    19/10/20 15:06:57 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 616 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 191019A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 340.02470, -17.32803 which is equivalent
to:

RA (J2000): 22h 40m 5.93s
Dec (J2000): -17d 19' 40.9"

with an uncertainty of 2.4 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB191019A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26045
SUBJECT: GRB 191019A: Swift-XRT refined Analysis
DATE:    19/10/20 15:32:57 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB),
J. D. Gropp (PSU), A. Tohuvavohu (U. Toronto), J.A. Kennea (PSU), P.A.
Evans (U. Leicester), J.P. Osborne (U. Leicester), K.L. Page (U.
Leicester) and K.K. Simpson report on behalf of the Swift-XRT team:

We have analysed 3.9 ks of XRT data for GRB 191019A (Simpson et al. GCN
Circ. 26031), from 3.3 ks to 17.2 ks after the BAT trigger. The data
are entirely in Photon Counting (PC) mode. The enhanced XRT position
for this burst was given by Osborne et al. (GCN Circ. 26043). The
results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00930285.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB191019A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26046
SUBJECT: GRB 191019A: Swift-BAT refined analysis
DATE:    19/10/20 16:54:32 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

H. A. Krimm (NSF), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), S. Laha (GSFC/UMBC),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
K. K. Simpson (PSU), M. Stamatikos (OSU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-239 to T+963 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 191019A (trigger #930285)
(Simpson et al., GCN Circ. 26031).  The BAT ground-calculated position is
RA, Dec = 340.035, -17.340 deg which is
   RA(J2000)  =  22h 40m 08.3s
   Dec(J2000) = -17d 20' 23.9"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 46%.

The mask-weighted light curve shows a complex structure with many
overlapping
pulses that starts at ~T0 and ends at ~T+90 s. The burst went out of the
BAT FOV at ~T+400 s. T90 (15-350 keV) is 64.35 +- 4.45 sec (estimated error
including systematics).

The time-averaged spectrum from T-0.83 to T+84.28 sec is best fit by a
simple
power-law model.  The power law index of the time-averaged spectrum is
2.25 +- 0.05.  The fluence in the 15-150 keV band is 1.0 +- 0.03 x 10^-5
erg/cm2.
The 1-sec peak photon flux measured from T-0.14 sec in the 15-150 keV band
is 5.7 +- 0.4 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/930285/BA/


GRB_name: GRB191019A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26048
SUBJECT: GRB 191019A: Swift-XRT updated analysis
DATE:    19/10/20 20:12:27 GMT
FROM:    Boris Sbarufatti at PSU  <bxs60@psu.edu>

B. Sbarufatti (PSU), P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester) 
and K.K. Simpson (PSU) report on behalf of the Swift-XRT team:


We have analyzed 8.5 ks of XRT data for GRB 191019a (Simpson et al. GCN Circ. 26031), from 3.3 ks to 32.4 ks after the BAT trigger.
The data are entirely in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Osborne et al. (GCN Circ. 26043).

The light curve can be modeled with a power-law decay with a decay index of alpha=1.0 (+/-0.2).

A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.0 (+/- 0.40). The
best-fitting absorption column is  consistent with the Galactic value of 3.3 x 10^20 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.4 x 10^-11 (4.1 x 10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total intrinsic column:     < 2.23 x 10^21 cm^-2
Galactic foreground: 3.3 x 10^20 cm^-2
Photon index:     2.0 (+/- 0.4)

If the light curve continues to decay with a power-law decay index of 1.0, the count rate at T+48 hours will be 1.2 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 4.1 x 10^-14 (4.9 x 10^-14) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00930285/.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB191019A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26053
SUBJECT: GRB 191019A: Swift/UVOT Detection
DATE:    19/10/21 22:05:22 GMT
FROM:    Sam LaPorte at PSU  <sjl5346@psu.edu>

GRB 191019A: Swift/UVOT Detection

S. J. LaPorte (PSU) and K. K. Simpson (PSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 191019A
3294 s after the BAT trigger (Simpson et al., GCN Circ. 26031).
A fading source consistent with the XRT position
(Evans et al. GCN Circ. 26034)
is detected in the initial UVOT exposures.

Preliminary detections and 3-sigma upper limits using the UVOT photometric
system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures
are:

Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

b               4541          4741             196
19.55+-0.30
uvm2        5361          5561             196              >19.20
u               4336          4536             196              >19.43
v               5156          5356              196             >18.75
uvw1        4131          4331              196              >19.13
uvw2        4952          5151              196              >19.28
white        4746          4946              196                19.66+-0.20

white      27982        28668              668                20.27+-0.18

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.04 in the direction of the burst
(Schlegel et al. 1998). Additionally, these magnitudes likely include a
contribution
from the probable host-galaxy, as reported by TSHAO (Reva et al., GCN Circ.
26036),
NOT (Fynbo et al., GCN Circ. 26041), and GROND (Guelbenzu et al. GCN Circ.
26042).


GRB_name: GRB191022A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26055
SUBJECT: GRB 191022A: Fermi GBM Final Real-time Localization
DATE:    19/10/22 07:00:19 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 06:50:05 UT on 22 Oct 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 191022A (trigger 593419810.073896 / 191022285).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 273.1, Dec = -23.1 (J2000 degrees, equivalent to J2000 18h 12m, -23d 06'), with a statistical uncertainty of 3.2 degrees.

The angle from the Fermi LAT boresight is 36.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191022285/quicklook/glg_skymap_all_bn191022285.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191022285/quicklook/glg_healpix_all_bn191022285.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191022285/quicklook/glg_lc_medres34_bn191022285.gif


GRB_name: GRB191022A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26056
SUBJECT: GRB 191022A: BALROG localization (Fermi Trigger 593419810 / GRB 191022285)
DATE:    19/10/22 08:05:28 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

F. Kunzweiler, B. Biltzinger, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
593419810 at 06:50:05 on 22 Oct. 2019 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 277.1+/-5.2 deg
Decl.(2000.0) = -19.6+/-3.6 deg
We estimate an additional systematic error of 2 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB191022285/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB191022285/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB191022285/json

                        


GRB_name: GRB191022B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26057
SUBJECT: GRB 191022B: Fermi GBM Final Real-time Localization
DATE:    19/10/22 08:21:19 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 08:11:06 UT on 22 Oct 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 191022B (trigger 593424671.253214 / 191022341).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 169.3, Dec = -31.2 (J2000 degrees, equivalent to J2000 11h 17m, -31d 11'), with a statistical uncertainty of 6.7 degrees.

The angle from the Fermi LAT boresight is 73.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191022341/quicklook/glg_skymap_all_bn191022341.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191022341/quicklook/glg_healpix_all_bn191022341.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191022341/quicklook/glg_lc_medres34_bn191022341.gif


GRB_name: GRB191019B
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26058
SUBJECT: GRB 191019B: AstroSat CZTI detection
DATE:    19/10/22 09:32:48 GMT
FROM:    Ramkrishna Gaikwad at IUCAA/AstroSat  <ramkrishna@iucaa.in>

R. Gaikwad, S. Gupta, V. Sharma and D. Bhattacharya (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data showed the detection of a GRB 191019B, which was also detected by Fermi GBM Final Real-time Localization (GCN #26040).

The source was clearly detected in the 40-200 keV energy range. The light curve shows multiple pulses of emission with the strongest peak at 2019-10-19 23:17:13.0 UT. The measured peak count rate associated with the burst is 265 cts/s above the background in the combined data of four quadrants, with a total of 7067 cts. The local mean background count rate was 501 cts/s. Using cumulative rates, we measure a T90 of 128.3 s.

It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.

CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.


GRB_name: GRB191019A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26059
SUBJECT: GRB 191019A: Nanshan-0.6m optical observations
DATE:    19/10/22 13:58:53 GMT
FROM:    Dong Xu at NAOC/CAS  <dxu@nao.cas.cn>

Z.P. Zhu, B.Y. Yu, D. Xu (NAOC), X. Gao (Urumqi No.1 Senior High School) 
report:

We observed the field of GRB 191019A (Simpson et al., GCN 26031) using 
the 0.6m NEXT telescope located at Nanshan, Xinjiang, China. 
Observations started at 15:34:01 UT (i.e., 21.5 min after the BAT 
trigger) and ended at 18:22:51 UT on 2019-10-19, and a series of 60 s, 
200 s, 300 s Sloan r-band frames were obtain in a high airmass.

A source is detected in our images at the XRT position (Osborne et al., 
GCN 26043), which is already present in Pan-STARRS with m(r) = 19.12 +/- 
0.01. The source had m(r) = 18.96 +/- 0.10 at the beginning and decayed 
to m(r) = 19.19 +/- 0.10 in about an hour. Because the flux difference 
is small and observations were carried out in high airmass, it's not 
clear if there is a GRB afterglow contribution. Our measurements are in 
agreement with that by NOT (Perley et al., GCN 26039; Fynbo et al., GCN 
26041) and GROND (Guelbenzu et al., GCN 26042).


GRB_name: GRB191023A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26060
SUBJECT: GRB 191023A: Fermi GBM Final Real-time Localization
DATE:    19/10/23 15:17:17 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 15:06:56 UT on 23 Oct 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 191023A (trigger 593536021.755384 / 191023630).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 295.3, Dec = 6.2 (J2000 degrees, equivalent to J2000 19h 41m, 6d 12'), with a statistical uncertainty of 1.8 degrees.

The angle from the Fermi LAT boresight is 88.0 degrees.

The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191023630/quicklook/glg_skymap_all_bn191023630.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191023630/quicklook/glg_healpix_all_bn191023630.fit

The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn191023630/quicklook/glg_lc_medres34_bn191023630.gif


GRB_name: GRB191023A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26061
SUBJECT: GRB 191023A: BALROG localization (Fermi Trigger 593536021 / GRB 191023630)
DATE:    19/10/23 15:28:42 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

B. Biltzinger, F. Kunzweiler, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
593536021 at 15:06:56 on 23 Oct. 2019 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 294.0+/-6.6 deg
Decl.(2000.0) = 3.3+/-2.0 deg
We estimate an additional systematic error of 2 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB191023630/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB191023630/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB191023630/json

                        


GRB_name: GRB191019A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26062
SUBJECT: GRB 191019A: NOT optical afterglow and host association confirmation
DATE:    19/10/23 21:55:37 GMT
FROM:    Daniel Perley at Liverpool JMU  <d.a.perley@ljmu.ac.uk>

D. A. Perley (LJMU), D. B. Malesani (DTU Space), A. J. Levan (Radboud 
Univ.), J. P. U. Fynbo (DAWN/NBI), and A. A. Djupvik (NOT) report on 
behalf of a larger collaboration:

We obtained additional observations of the optical counterpart (Reva et 
al., GCN 26036; LaPorte & Simpson, GCN 26053; Zhu et al., GCN 26059) of 
GRB 191019A (Simpson et al., GCN 26031), using the Nordic Optical 
Telescope (NOT) equipped with the ALFOSC camera.  A total of 25 minutes 
exposure was secured with mid time Oct 22.875 UT (77.8 hr after the GRB).

The archival object consistent with the XRT error circle is well 
detected, with a magnitude of i = 18.71 +/- 0.02 AB, consistent with the 
Pan-STARRS tabulated value of i = 18.71 +/- 0.01 and slightly fainter 
than our earlier observation (Perley et al., GCN  26039), for which the 
mid time was 4.60 hr after the GRB.

Digital image subtraction was carried out with ISIS (Alard 2000, A&AS, 
144, 363) between the two epochs. A clear point-like residual is 
detected, for which we measure a magnitude i = 21.78 +/- 0.05 AB 
(assuming no residual flux in our second epoch). Its position calibrated 
against the Gaia catalog is:

RA(J2000) = 22:40:05.89
Dec(J2000) = -17:19:42.6

(+/- 0.3")

An image showing the subtraction result is available here: 
http://outer.space.dtu.dk/~dmales/GRB/191019A/subtraction.jpg

The transient location is 0.07" east of the galaxy nucleus, 
strengthening the case for a physical association between the two 
objects.  The offset is within the margin of error, although the NOT 
spectroscopy (Fynbo et al., GCN 26041) does not suggest that the source 
is an AGN.

Our observations thus confirm the presence of a transient optical source 
at a position consistent with the X-ray afterglow, located to within the 
errors on top of the nucleus of the candidate host. The lack of any 
non-obscured star formation makes this system unique among long-duration 
GRBs.

We encourage observations of this puzzling source at all wavelengths.









DisclaimerNone


GRB_name: GRB191024A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26063
SUBJECT: GRB 191024A: Swift detection of a burst
DATE:    19/10/24 05:10:57 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

K. L. Page (U Leicester), J.D. Gropp (PSU), N. J. Klingler (PSU),
D. M. Palmer (LANL) and A. Tohuvavohu (Toronto) report on behalf of
the Neil Gehrels Swift Observatory Team:

At 04:42:52 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 191024A (trigger=931242).  Swift slewed to the burst after
a delay to clear the Earth limb observing constraint. 
The BAT on-board calculated location is 
RA, Dec 10.147, -67.139 which is 
   RA(J2000) = 00h 40m 35s
   Dec(J2000) = -67d 08' 21"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The first 8 seconds of the BAT light curve 
showed a FRED structure structure with an extrapolated duration of 
about 12 sec.  (Further light curve data will not be available until
the full dataset is downlinked to the ground.)  The peak count rate
was ~2000 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 04:56:41.7 UT, 829.1 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 10.11387, -67.14323 which is equivalent
to:
   RA(J2000)  = 00h 40m 27.33s
   Dec(J2000) = -67d 08' 35.6"
with an uncertainty of 4.5 arcseconds (radius, 90% containment). This
location is 48 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper.  We
cannot determine whether the source is fading at the present time. No
spectrum from the promptly downlinked event data is yet available to
determine the column density. 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 832 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.02. 

Burst Advocate for this burst is K. L. Page (klp5 AT leicester.ac.uk). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB191024A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26064
SUBJECT: GRB 191024A: Enhanced Swift-XRT position
DATE:    19/10/24 08:53:34 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 839 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 191024A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 10.11473, -67.14506 which is equivalent
to:

RA (J2000): 00h 40m 27.53s
Dec (J2000): -67d 08' 42.2"

with an uncertainty of 2.4 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB191024A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26065
SUBJECT: GRB191024A: MASTER optical observation 
DATE:    19/10/24 10:03:29 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, E. Gorbovskoy, V.Kornilov, F.Balakin,N.Tyurina,P.Balanutsa,A.Kuznetsov, V.Vladimirov, D. Vlasenko, I.Gorbunov,
D.Zimnukhov,V.Senik, T.Pogrosheva, K.Pozdnyakov,A.Chasovnikov, V.Topolev, D.Kuvshinov(Lomonosov Moscow State University, SAI,Physics Department),
R. Podesta, C.Lopez, F. Podesta, C.Francile(Observatorio Astronomico FelixAguilar OAFA),
H.Levato(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),
R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias),
D. Buckley(South African Astronomical Observatory),
O.A. Gres, N.M. Budnev, O.Ershova(Irkutsk State University, API),
A. Tlatov, D. Dormidontov(Kislovodsk Solar Station of the Pulkovo Observatory),
V. Yurkov, A. Gabovich, Yu. Sergienko(Blagoveschensk Educational State University)

MASTER-OAFA 
(MASTER Global Robotic Net http://observ.pereplet.ru, Lipunov et al.,2010,Advances in Astronomy, vol.2010, 30L)
located in Argentina (OAFA observatory of San Juan National University) 
was pointed to the SWIFT GRB191024A
(Page et al.GCN #26063, Beardmore et al. GCN 26064 trigger No 931242, XRT R.A.Dec(2000)=00h 40m 27.53s -67d 08' 42.2")
errorbox  37 sec after trigger time at 2019-10-24 04:43:29 UT,
with upper limit up to  14.4 on 10s images (18.2 mag on 1800s sum)
There is no OT on first images.

The observations began at zenith distance = 38 deg. The sun  altitude  was -47.1 deg.

The galactic latitude b = -60 deg., longitude l = 98 deg.

Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/event.php?id=1175693

We obtained the following upper limits:

Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

       42 |         MASTER-OAFA |   C |    10 | 14.4 |
       83 |         MASTER-OAFA |   C |    10 | 13.8 |
      131 |         MASTER-OAFA |   C |    20 | 14.5 |
      187 |         MASTER-OAFA |   C |    30 | 14.6 |
      237 |         MASTER-OAFA |   C |   130 | 15.3 |  Coadd
      253 |         MASTER-OAFA |   C |    40 | 14.3 |
      335 |         MASTER-OAFA |   C |    60 | 14.9 |
      436 |         MASTER-OAFA |   C |    80 | 15.6 |
      546 |         MASTER-OAFA |   C |   300 | 16.1 |  Coadd
      558 |         MASTER-OAFA |   C |   100 | 15.2 |
      700 |         MASTER-OAFA |   C |   120 | 15.4 |
      866 |         MASTER-OAFA |   C |   150 | 16.3 |
     1873 |         MASTER-OAFA |   C |  1800 | 17.7 |  Coadd
     6099 |         MASTER-OAFA |   C |  1800 | 18.2 |  Coadd


Reduction will be continued.
The message may be cited.


GRB_name: GRB191024A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26066
SUBJECT: GRB 191024A: GROND early upper limits
DATE:    19/10/24 13:47:49 GMT
FROM:    Jan Bolmer at MPE/Garching  <jan@bolmer.de>

J. Bolmer (MPE Garching), and P. Schady (Univ. of Bath),  report:

We observed the field of GRB 191024A (Swift trigger 931242; Page et al., GCN #26063)
simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted
at the 2.2 m MPG telescope at ESO La Silla Observatory (Chile).

Observations started at 04:45:40 UT on 24th October, 3 minutes after the GRB trigger.
They were performed at an average seeing of 1.2" and at an average airmass of 1.4.

We do not detect a source at the enhanced position of the Swift-XRT afterglow
(Beardmore et al., GCN #26064) â€” down to the following 3-sigma limits (all AB magnitude) â€” 
in the stacked images of observations taken between 168 and 5906 seconds post trigger
(total integration time of 95 min).

g' > 25.5 mag
r' > 25.6 mag
i' > 24.8 mag
z' > 23.4 mag
J > 21.9 mag
H > 21.4 mag
K > 20.2 mag


Given limits are calibrated against Sky-Mapper and 2MASS field stars and are not
corrected for the Galactic foreground extinction corresponding to a reddening of
E_(B-V)= 0.01 in the direction of the burst (Schlafly & Finkbeiner 2011).


