| Summary table |
|---|
| Variable |
Value |
Source |
| GRB_name_Fermi |
GRB250207053 |
|
| T0 |
1:16:03 UTC |
GCN_circulars,Fermi GBM final loc |
| ra |
16.0891° |
Swift |
| decl |
-12.1646° |
Swift |
| pos_error |
5.44e-05° |
Swift |
| T90 |
19.712 s |
Fermi_GBM |
| T90_error |
0.724 s |
Fermi_GBM |
| T90_start |
1:16:03.664 UTC |
Fermi_GBM |
| fluence |
7.93e-06 erg/cm² |
Fermi_GBM |
| fluence_error |
3.31e-08 erg/cm² |
Fermi_GBM |
| T100 |
20.376 s |
|
| GBM_located |
False |
|
| mjd |
60713.0528125 |
GCN_circulars,Fermi GBM final loc |
| Fermi GBM table |
|---|
| GRB_name_Fermi |
GRB250207053 |
| trigger_name |
bn250207053 |
| ra |
16.0892° |
| decl |
-12.1633° |
| pos_error |
3.06e+00° |
| datum |
2025-02-07 |
| t_trigger |
1:16:03.152 UTC |
| T90 |
19.712 s |
| T90_error |
0.724 s |
| T90_start |
1:16:03.664 UTC |
| fluence |
7.93e-06 erg/cm² |
| fluence_error |
3.31e-08 erg/cm² |
| flux_1024 |
4.75e+00 erg/cm²/s |
| flux_1024_error |
2.96e-01 erg/cm²/s |
| flux_1024_time |
1.16e+01 erg/cm²/s |
| flux_64 |
7.05e+00 erg/cm²/s |
| flux_64_error |
1.41e+00 erg/cm²/s |
| IPN table |
|---|
| GRB_name |
GRB250207A |
| ra |
16.1167° |
| decl |
-12.1500° |
| pos_error |
5.00e-02° |
| Swift table |
|---|
| GRB_name |
GRB250207A |
| t_trigger |
1:16:07 UTC |
| ra |
16.0891° |
| decl |
-12.1646° |
| pos_error |
5.44e-05° |
| GCN 39181 table |
|---|
| GRB_name |
GRB250207A |
| GCN_number |
39181 |
| Detection_method |
Fermi GBM final loc |
| t_trigger |
1:16:03 UTC |
| ra |
11.8000° |
| decl |
-13.3000° |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 39181
SUBJECT: GRB 250207A: Fermi GBM Final Real-time Localization
DATE: 25/02/07 01:26:45 GMT
FROM: Fermi GBM Team at MSFC/Fermi-GBM
The Fermi GBM team reports the detection of a likely LONG GRB
At 01:16:03 UT on 7 Feb 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250207A (trigger 760583768.15163 / 250207053).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 11.8, Dec = -13.3 (J2000 degrees, equivalent to J2000 00h 47m, -13d 18'), with a statistical uncertainty of 3.2 degrees.
The angle from the Fermi LAT boresight is 47.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250207053/quicklook/glg_skymap_all_bn250207053.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250207053/quicklook/glg_healpix_all_bn250207053.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250207053/quicklook/glg_lc_medres34_bn250207053.gif
|
| GCN 39182 table |
|---|
| GRB_name |
GRB250207A |
| GCN_number |
39182 |
| Detection_method |
Swift Det |
| t_trigger |
1:16:07 UTC |
| ra |
16.1150° |
| decl |
-12.1590° |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 39182
SUBJECT: GRB 250207A: Swift detection of a burst with optical counterpart
DATE: 25/02/07 01:34:53 GMT
FROM: Jamie Kennea at Penn State
M. Ferro (INAF-OAB), R. Gupta (NASA GSFC), J. A. Kennea (PSU),
K. L. Page (U Leicester) and B. Sbarufatti (INAF-OAB) report on behalf
of the Neil Gehrels Swift Observatory Team:
At 01:16:07 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 250207A (trigger=1287821). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 16.115, -12.159 which is
RA(J2000) = 01h 04m 28s
Dec(J2000) = -12d 09' 30"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve showed a complex
structure with a duration of about 30 sec. The peak count rate
was ~3847 counts/sec (15-350 keV), at ~6 sec after the trigger.
The XRT began observing the field at 01:17:53.2 UT, 105.9 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 16.0892, -12.1633 which is equivalent to:
RA(J2000) = 01h 04m 21.41s
Dec(J2000) = -12d 09' 47.9"
with an uncertainty of 5.9 arcseconds (radius, 90% containment). This
location is 92 arcseconds from the BAT onboard position, within the BAT
error circle. Despite the onboard localisation, no X-ray source was
detected in 85 s of promptly-downlinked data, suggesting that the
initial centroid may equally have been a cosmic ray. This position
should therefore be treated with caution.
The initial flux in the 2.5 s image was 7.54e-10 erg cm^-2 s^-1 (0.2-10
keV).
UVOT took a finding chart exposure of 150 seconds with the White filter
starting 113 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
RA(J2000) = 01:04:21.41 = 16.08919
DEC(J2000) = -12:09:52.5 = -12.16458
with a 90%-confidence error radius of about 0.74 arc sec. This position is 4.6
arc sec. from the center of the XRT error circle. The estimated magnitude is
15.04 with a 1-sigma error of about 0.14. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.027.
Burst Advocate for this burst is M. Ferro (matteo.ferro 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/)
|
| GCN 39186 table |
|---|
| GRB_name |
GRB250207A |
| GCN_number |
39186 |
| Detection_method |
Swift-BAT Det |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 39186
SUBJECT: GRB 250207A: COLIBRÃ/DDRAGO Optical Afterglow Detection
DATE: 25/02/07 03:20:08 GMT
FROM: Camila Angulo Valdez at UNAM
Camila Angulo (UNAM), Alan M. Watson (UNAM), Noémie Globus (UNAM), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Dalya Akl (AUS), Sarah Antier (OCA), Jean-Luc Atteia (IRAP), Rosa L. Becerra (Università degli Studi di Roma Tor Vergata), Nathaniel R. Butler (ASU), Damien Dornic (CPPM), Jean-Grégoire Ducoin (CPPM), Francis Fortin (IRAP), Francesco Magnani (CPPM), Margarita Pereyra (UNAM), and Benjamin Schneider (LAM) report:
We imaged the field of GRB 250207A detected by Fermi/GBM (Fermi GBM Team, GCN Circ. 39181) and Swift/BAT (Ferro et al., GCN Circ.39182) with the DDRAGO wide-field camera on the COLIBRà (SVOM/F-GFT) telescope at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir in Mexico.
We observed from 2025-02-07 02:34 to 02:55 UTC (78 to 99 min after the burst), with a midpoint of 88.5 minutes after the event, and obtained 960 seconds of exposure in the r filter in good weather conditions. The data were reduced and stacked using custom software and then calibrated against the PS1 catalog and analysed using STDPipe (Karpov 2021).
At the position of the afterglow detected by XRT and UVOT (Ferro et al., GCN Circ. 39182), we detect a source with
r = 18.90 +/- 0.01
and confirm fading relative to the UVOT observation.
Our magnitude is not corrected for Galactic extinction.
Further observations are planned.
We warmly thank the COLIBRà and DDRAGO engineering teams and the staff of the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir.
|
| GCN 39199 table |
|---|
| GRB_name |
GRB250207A |
| GCN_number |
39199 |
| Detection_method |
Swift-UVOT Det |
| ra |
16.0891° |
| decl |
-12.1646° |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 39199
SUBJECT: GRB 250207A: Swift/UVOT Detection
DATE: 25/02/07 10:42:24 GMT
FROM: Paul Kuin at MSSL
Paul Kuin (MSSL/UCL) and M. Ferro (INAF-OAB) report on behalf of
the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 250207A
113 s after the BAT trigger (Ferro et al., GCN Circ. 39182). The source
was
also reported by Angulo et al. GCN Circ. 39186.
The preliminary UVOT position is:
RA (J2000) = 01:04:21.39 = 16.08912 (deg.)
Dec (J2000) = -12:09:52.5 = -12.16459 (deg.)
with an estimated uncertainty of 0.42 arc sec. (radius, 90% confidence).
Preliminary detections 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 113 263 147 15.00 +/- 0.02
v 655 674 19 16.89 +/- 0.20
b 581 600 19 16.56 +/- 0.09
u 326 575 246 15.65 +/- 0.03
uvm2 679 699 19 > 17.3 (3 sigma UL)
uvw2 630 650 19 > 17.6 (3 sigma UL)
The lack of detection in the UVM2 band may indicate a redshift greater
than 1.3.
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.027 in the direction of the burst
(Schlegel et al. 1998).
|
| GCN 39202 table |
|---|
| GRB_name |
GRB250207A |
| GCN_number |
39202 |
| Detection_method |
Optical |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 39202
SUBJECT: GRB 250207A: REM optical afterglow detection
DATE: 25/02/07 13:23:26 GMT
FROM: Riccardo Brivio at INAF-OAB
R. Brivio, M. Ferro, P. D’Avanzo, S. Covino (INAF-OAB), A. Melandri (INAF-OAR), D. B. Malesani (DAWN/NBI and Radboud Univ.), G. Tagliaferri, D. Fugazza (INAF-OAB) report on behalf of the REM team:
We observed the field of GRB 250207A, detected by Fermi/GBM (Fermi GBM Team, GCN 39181) and Swift/BAT (Ferro et al., GCN 39182) with the REM 60cm robotic telescope located at the ESO observatory of La Silla (Chile). The observations were carried in the g, r, i, z, J, H, K bands, starting on 2025 February 07 at 01:17:08 UT (i.e. 61 s after the Swift trigger), and lasting for about 2 hours.
From preliminary photometry we detect the counterpart in the optical images at the position of the optical afterglow (Angulo et al., GCN 39186; Kuin & Ferro, GCN 39199) with the following magnitude:
r = 12.7 +/- 0.1 (AB; calibrated against the Pan-STARRS catalogue)
at a mid-time of t - t0 = 66 s after the trigger.
The analysis of the NIR data is ongoing. |
| GCN 39209 table |
|---|
| GRB_name |
GRB250207A |
| GCN_number |
39209 |
| Detection_method |
Optical |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 39209
SUBJECT: GRB 250207A: FRAM-Auger optical detection
DATE: 25/02/07 17:00:05 GMT
FROM: Martin Jelinek at Astro.Inst-AVCR,Ondrejov
Martin Jelinek (ASU CAS Ondrejov, CZ), Martin Masek, Petr Janecek,
Sergey Karpov, Jakub Jurysek, Jan Ebr, Ronan Cunniffe, Petr
Travnicek, Michael Prouza (Institute of Physics, Prague, CZ) and
Jan Strobl (ASU CAS Ondrejov, CZ) report:
The 30cm robotic telescope FRAM-Auger in Malargue (Argentina)
reacted robotically to the Swift/BAT and Fermi/GBM alert of
GRB250207A (Fermi GBM Team, GCN 39181; Ferro et al., GCN 39182),
starting with a series of 20s R-band images at 01:16:49 UT, i.e. 42s
post trigger.
We detect the optical afterglow at the position reported by Brivio
et al. (GCN 39202), Kuin & Ferro (GCN 39199), and Angulo et al.
(GCN 39186) in our initial frames. The early light curve shows a
relatively steep decay with a power-law index alpha ~ 1.6. Extrapolation
of this decay rate appears inconsistent with later observations by
COLIBRI (Angulo et al., GCN 39186), suggesting a possible transition
in the light curve slope beyond ~600s post burst.
|
| GCN 39212 table |
|---|
| GRB_name |
GRB250207A |
| GCN_number |
39212 |
| Detection_method |
Swift-BAT Det |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 39212
SUBJECT: GRB 250207A: REM IR afterglow detection
DATE: 25/02/07 18:01:45 GMT
FROM: Matteo Ferro at INAF-OAB
M. Ferro, R. Brivio, P. D’Avanzo, S. Covino, D. Fugazza (INAF-OAB) report on behalf of the REM team:
We observed the field of GRB 250207A, detected by Fermi/GBM (Fermi GBM Team, GCN 39181) and Swift/BAT (Ferro et al., GCN 39182) with the REM 60cm robotic telescope located at the ESO observatory of La Silla (Chile). The observations were carried in the g, r, i, z, J, H, K bands, starting on 2025 February 07 at 01:17:08 UT (i.e. 61 s after the Swift trigger), and lasting for about 2 hours.
From preliminary photometry we detect the counterpart in the IR images at the position of the optical afterglow (Angulo et al., GCN 39186; Kuin & Ferro, GCN 39199; Brivio et al., GCN 39202; Jelinek et al., GCN 39209) with the following magnitude:
H ~ 13.3 (Vega; calibrated against the 2MASS catalogue)
at a mid-time of t - t0 = 26.6 minutes after the trigger. |
| GCN 39217 table |
|---|
| GRB_name |
GRB250207A |
| GCN_number |
39217 |
| Detection_method |
Swift-XRT Det |
| ra |
16.0893° |
| decl |
-12.1648° |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 39217
SUBJECT: GRB 250207A: Enhanced Swift-XRT position
DATE: 25/02/07 22:54:13 GMT
FROM: Phil Evans at U of Leicester
J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester)
report on behalf of the Swift-XRT team.
Using 1772 s of XRT Photon Counting mode data and 3 UVOT
images for GRB 250207A, 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 = 16.08929, -12.16479 which is equivalent
to:
RA (J2000): 01h 04m 21.43s
Dec (J2000): -12d 09' 53.3"
with an uncertainty of 2.2 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.
|
| GCN 39221 table |
|---|
| GRB_name |
GRB250207A |
| GCN_number |
39221 |
| Detection_method |
Swift-XRT Other |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 39221
SUBJECT: GRB 250207A: Swift-XRT refined Analysis
DATE: 25/02/08 01:34:17 GMT
FROM: Phil Evans at U of Leicester
A. Melandri (INAF-OAR), T. Sbarrato (INAF-OAB), D.N. Burrows (PSU), M.
A. Williams (PSU), S. Dichiara (PSU), J.P. Osborne (U. Leicester), K.L.
Page (U. Leicester), P. D'Avanzo (INAF-OAB) and P.A. Evans report on
behalf of the Swift-XRT team:
We have analysed 6.0 ks of XRT data for GRB 250207A, from 100 s to 73.6
ks after the BAT trigger. The data comprise 370 s in Windowed Timing
(WT) mode (the first 4 s were taken while Swift was slewing) with the
remainder in Photon Counting (PC) mode.
The late-time light curve (from T0+4.2 ks) can be modelled with a
power-law decay with a decay index of alpha=1.22 (+0.13, -0.10).
A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.14 (+/-0.06). The
best-fitting absorption column is 6.7 (+/-1.2) x 10^20 cm^-2, in
excess of the Galactic value of 2.4 x 10^20 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 2.02 (+0.16, -0.15)
and a best-fitting absorption column of 5.5 (+3.5, -3.1) x 10^20 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum is 3.3 x 10^-11 (3.8 x 10^-11) erg cm^-2
count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 5.5 (+3.5, -3.1) x 10^20 cm^-2
Galactic foreground: 2.4 x 10^20 cm^-2
Excess significance: <1.6 sigma
Photon index: 2.02 (+0.16, -0.15)
If the light curve continues to decay with a power-law decay index of
1.22, the count rate at T+24 hours will be 0.010 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.4 x
10^-13 (3.9 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/01287821.
This circular is an official product of the Swift-XRT team.
|
| GCN 39245 table |
|---|
| GRB_name |
GRB250207A |
| GCN_number |
39245 |
| Detection_method |
Swift-BAT Det |
| ra |
16.0970° |
| decl |
-12.1650° |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 39245
SUBJECT: GRB 250207A: Swift-BAT refined analysis
DATE: 25/02/09 00:53:00 GMT
FROM: Rahul Gupta at NASA GSFC
M. J. Moss (GSFC), S. D. Barthelmy (GSFC),
M. Ferro (INAF-OAB), R. Gupta (GSFC),
H. A. Krimm (NSF), S. Laha (GSFC/UMBC),
A. Y. Lien (U Tampa), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Parsotan (GSFC),
D. Sadaula (GSFC/UMBC), T. Sakamoto (AGU)
(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 250207A (trigger #1287821)
(Ferro, et al., GCN Circ. 39182). The BAT ground-calculated position is
RA, Dec = 16.097, -12.165 deg which is
RA(J2000) = 01h 04m 23.4s
Dec(J2000) = -12d 09' 55.0"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 72%.
The masked weighted BAT light curve shows a prominent multi-peaked structure, with the most significant activity occurring within the first 50 seconds after the trigger. T90 (15-350 keV) is 52.54 +- 19.87 sec (estimated error including systematics).
The time-averaged spectrum from T-6.60 to T+100.22 sec is the best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.27 +- 0.08. The fluence in the 15-150 keV band is 3.7 +- 0.2 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T+7.01 sec in the 15-150 keV band is 2.6 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
The results of the batgrbproduct analysis are available at
https://swift.gsfc.nasa.gov/results/batgrbcat/BAT_refined_circular/1287821 |
| GCN 39274 table |
|---|
| GRB_name |
GRB250207A |
| GCN_number |
39274 |
| Detection_method |
Optical |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 39274
SUBJECT: GRB 250207A: Skynet optical afterglow observations
DATE: 25/02/11 01:35:36 GMT
FROM: dschlekat@unc.edu
Donovan Schlekat, Dylan Dutton, Daniel Reichart, Joshua Haislip, and Vladimir Kouprianov report on behalf of the Skynet Robotic Telescope Network at the University of North Carolina at Chapel Hill.
We observed the field of GRB 250207A detected by Fermi (The Fermi GBM Team, GCN 39181) and Swift (Ferro et al., GCN 39182; Osborne et al., GCN 39217; Melandri et al., GCN 39221; Moss et al., GCN 39245) with two of Skynet's PROMPT telescopes located at the Cerro Tololo Inter-American Observatory. The observation began at 01:20:03 UT on February 7 2025, roughly 4 minutes after the Swift-BAT trigger and lasted for around 14 minutes until the field was no longer observable. Observations were performed in the B, V, R, and I bands. Exposure lengths were calculated using our automated exposure length scaling model.
We detect the optical afterglow (Ferro et al., GCN 39182; Angulo et al., GCN 39186; Kuin & Ferro, GCN 39199; Brivio et al., GCN 39202; Jelinek et al., GCN 39209; Ferro et al., 39212; Ror et al., 39250) in the V, R, and I bands. The photometry of the initial detection for each band is reported below.
Tmid - T0 (s)| Telescope | Filter | Exposure (s) | Mag | Mag Error
------------------------------------------------------------------
747.0 | PROMPT-6 | V | 22 | 16.854 | 0.064
779.0 | PROMPT-5 | R | 16 | 16.593 | 0.097
805.0 | PROMPT-6 | I | 10 | 16.570 | 0.061
Our images have been calibrated using stars from the APASS catalog. Magnitudes were not corrected for dust extinction. |
| GCN 39284 table |
|---|
| GRB_name |
GRB250207A |
| GCN_number |
39284 |
| Detection_method |
Konus-Wind Det |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 39284
SUBJECT: Konus-Wind detection of GRB 250207A
DATE: 25/02/11 13:50:11 GMT
FROM: Anna Ridnaia at Ioffe Institute
A. Ridnaia, D. Frederiks, A. Lysenko, D. Svinkin,
A. Tsvetkova, M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:
The long-duration GRB 250207A
(Fermi-GBM detection: Fermi GBM team, GCN 39181;
Swift-BAT detection: Ferro et al., GCN 39182; Moss et al., GCN 39245)
was detected by Konus-Wind (KW) in the waiting mode.
A Bayesian block analysis of the KW waiting mode data
reveals a >27 sigma count rate increase in the interval
from T0-7.699 s to T0+15.853 s where T0 = T0(BAT) = 01:16:07.33 UT.
The KW light curve of this burst is available at
http://www.ioffe.ru/LEA/GRBs/GRB250207A/
Modeling a time-integrated spectrum of the burst
(from T0-7.699 s to T0+15.853 s)
by a power law with exponential cutoff (CPL) model
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep):
yields alpha = -1.26 (-0.12, + 0.14) and Ep = 329(-64,+91) keV.
The total burst fluence is 1.04(-0.11,+0.13)x10^-5 erg/cm^2,
and the 2.944 s peak energy flux, measured from T0+4.077 s,
is 7.05(-0.98,+1.08)x10^-7 erg/cm^2.
(both in the 20 keV - 10 MeV energy range).
All the quoted errors are estimated at the 68% confidence level.
All the presented results are preliminary.
|
| GCN 39291 table |
|---|
| GRB_name |
GRB250207A |
| GCN_number |
39291 |
| Detection_method |
Fermi GBM Det |
| t_trigger |
1:16:03.150 UTC |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 39291
SUBJECT: GRB 250207A: Fermi GBM Observation
DATE: 25/02/11 21:31:46 GMT
FROM: oindabimukherjee@gmail.com
O. Mukherjee (USRA), R. Hamburg (USRA) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:
"At 01:16:03.15 UT on 07 February 2025, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 250207A (trigger 760583768/250207053).
which was also detected by Swift BAT (Ferro et al. 2025, GCN 39182), COLIBRÃ/DDRAGO (Angulo et al. 2025, GCN 39186),
Swift/UVOT (Kuin et al. 2025, GCN 39199), and Konus-Wind (Ridnaia. et al. 2025, GCN 39284)
The Fermi GBM Final Real-time Localization (GCN 39181) is consistent with the Swift BAT position.
The angle from the Fermi LAT boresight is 46 degrees.
The GBM light curve consistes of a single emission episode with multiple peaks with a duration (T90)
of about 20 s (50-300 keV). The time-averaged spectrum
from T0-3.1 to T0+25.6 s is best fit by
a power law function with an exponential high-energy cutoff.
The power law index is -1.10 +/- 0.06 and the cutoff energy,
parameterized as Epeak, is 290 +/- 30 keV.
The event fluence (10-1000 keV) in this time interval is
(1.04 +/- 0.04)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+12 s in the 10-1000 keV band is 4.7 +/- 0.3 ph/s/cm^2.
A Band function fits the spectrum equally well
with Epeak= 240 +/- 30 keV, alpha = -1.03 +/- 0.08 and beta = -2.3 +/- 0.3.
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/" |
| GCN 39463 table |
|---|
| GRB_name |
GRB250207A |
| GCN_number |
39463 |
| Detection_method |
Swift-XRT Other |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 39463
SUBJECT: GRB 250207a: ATCA Radio Upper Limits
DATE: 25/02/25 01:32:43 GMT
FROM: agul8829@uni.sydney.edu.au
A. Gulati (USyd), G. E. Anderson (Curtin), S. Chastain (UNM), A. J. van der Horst (GWU), J. K. Leung (UofT/HUJI), and L. Rhodes (TSI/McGill) on behalf of the ATCA PanRadio GRB collaboration
We observed Swift and Fermi-detected GRB 250207A (Ferro et al., GCN 39182; Fermi GBM Collaboration, GCN 39181) as part of The Australia Telescope Compact Array (ATCA) "PanRadio GRB" Large Project C3542 (PI: G. Anderson) at 5.5 and 9 GHz on 2025-02-12, 2025-02-14 and 2025-02-21.
No radio sources were detected near the Swift/XRT enhanced position (Osborne et al., GCN 39217 )in any of the observation epochs. The 3-sigma upper limits for the 9 GHz observations are 174, 96, and 60 uJy respectively.
We thank the CSIRO Space and Astronomy staff for supporting these observations.
We acknowledge the Gomeroi people as the traditional owners of the Observatory site. The Australia Telescope Compact Array is part of the Australia Telescope National Facility (https://ror.org/05qajvd42) which is funded by the Australian Government for operation as a National Facility managed by CSIRO. |