GRB181228A

This page lists all entries on GRB181228A in GRBweb

Summary Fermi GBM IPN Swift GCN 23570 GCN 23571 GCN 23574 GCN 23575 GCN 23576 GCN 23578 GCN 23579 GCN 23580 GCN 23581 GCN 23583 GCN 23584 GCN 23588 GCN 23590 GCN 23593 GCN 23594 GCN 23596 GCN 23669

Summary table
Variable Value Source
GRB_name_Fermi GRB181228120
T0 2:53:14.960 UTC GCN_circulars,Fermi GBM Det
ra 49.8122° Swift
decl 13.2021° Swift
pos_error 1.81e-04° Swift
T90 17.664 s Fermi_GBM
T90_error 0.32 s Fermi_GBM
T90_start 2:53:16.883 UTC Fermi_GBM
fluence 2.12e-05 erg/cm² Fermi_GBM
fluence_error 5.63e-08 erg/cm² Fermi_GBM
T100 259.34 s
GBM_located False
mjd 58480.120312037034 GCN_circulars,Fermi GBM Det
Fermi GBM table
GRB_name_Fermi GRB181228120
trigger_name bn181228120
ra 49.8121°
decl 13.2022°
pos_error 2.62e+00°
datum 2018-12-28
t_trigger 2:53:14.963 UTC
T90 17.664 s
T90_error 0.32 s
T90_start 2:53:16.883 UTC
fluence 2.12e-05 erg/cm²
fluence_error 5.63e-08 erg/cm²
flux_1024 1.60e+01 erg/cm²/s
flux_1024_error 3.60e-01 erg/cm²/s
flux_1024_time 1.56e+01 erg/cm²/s
flux_64 1.84e+01 erg/cm²/s
flux_64_error 1.51e+00 erg/cm²/s
IPN table
GRB_name GRB181228A
ra 49.8292°
decl 13.2000°
pos_error 5.00e-02°
Swift table
GRB_name GRB181228A
t_trigger 2:53:17 UTC
ra 49.8122°
decl 13.2021°
pos_error 1.81e-04°
T90 257.3 s
fluence 1.00e-05 erg/cm²
GCN 23570 table
GRB_name GRB181228A
GCN_number 23570
Detection_method Swift Det
t_trigger 2:53:17 UTC
ra 49.8310°
decl 13.1950°
Circular_text TITLE: GCN CIRCULAR NUMBER: 23570 SUBJECT: GRB 181228A: Swift detection of a burst DATE: 18/12/28 03:07:38 GMT FROM: Scott Barthelmy at NASA/GSFC M. J. Moss (George Washington University), S. D. Barthelmy (GSFC), A. D'Ai (INAF-IASFPA), V. D'Elia (SSDC), J. A. Kennea (PSU), A. Y. Lien (GSFC/UMBC) and A. Tohuvavohu (PSU) report on behalf of the Neil Gehrels Swift Observatory Team: At 02:53:17 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 181228A (trigger=879909). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 49.831, +13.195, which is RA(J2000) = 03h 19m 19s Dec(J2000) = +13d 11' 42" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows multiple overlapping peaks with a duration of about 25 sec. The peak count rate was ~7000 counts/sec (15-350 keV), at ~13 sec after the trigger. The XRT began observing the field at 02:54:40.1 UT, 82.5 seconds after the BAT trigger. Using promptly downlinked data we find a bright, uncatalogued X-ray source with an enhanced position: RA, Dec 49.8114, 13.2000 which is equivalent to: RA(J2000) = 03h 19m 14.75s Dec(J2000) = +13d 12' 00.1" with an uncertainty of 2.6 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. 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. The initial flux in the 2.5 s image was 5.46e-10 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of nominal 150.000 seconds with the White filter starting 93 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. Data from the 2.7'x2.7' sub-image are not available at this time. 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 0.51. Burst Advocate for this burst is M. J. Moss (mikejmoss3 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/too.html.)
GCN 23571 table
GRB_name GRB181228A
GCN_number 23571
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 23571 SUBJECT: GRB 181228A: KAIT Optical Upper Limit DATE: 18/12/28 04:15:53 GMT FROM: Weikang Zheng at UC Berkeley 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 181228A (Moss et al., GCN 23570) starting at 03:03:30 UT, 613 s after the burst. Observations were performed with an automatic sequence in the clear (roughly R), V, and I filters, and the exposure time was 20 s per image. We do not detect any optical afterglow candidate within the XRT position error circle (Moss et al., GCN 23570), neither in single image, nor in the co-add images. The typical limiting magnitude of our single clear image is about 18.5 mag calibrated to the Pan-STARRS1 catalog.
GCN 23574 table
GRB_name GRB181228A
GCN_number 23574
Detection_method Swift-XRT Det
ra 49.8121°
decl 13.2021°
Circular_text TITLE: GCN CIRCULAR NUMBER: 23574 SUBJECT: GRB 181228A: Enhanced Swift-XRT position DATE: 18/12/28 06:34:33 GMT FROM: Phil Evans at U of Leicester A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) report on behalf of the Swift-XRT team. Using 1212 s of XRT Photon Counting mode data and 2 UVOT images for GRB 181228A, 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 = 49.81214, +13.20208 which is equivalent to: RA (J2000): 03h 19m 14.91s Dec (J2000): +13d 12' 07.5" 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.
GCN 23575 table
GRB_name GRB181228A
GCN_number 23575
Detection_method Optical
ra 49.8127°
decl 13.2019°
Circular_text TITLE: GCN CIRCULAR NUMBER: 23575 SUBJECT: GRB 181228A: REM NIR detection DATE: 18/12/28 09:35:37 GMT FROM: Paolo D'Avanzo at INAF-OAB P. D'Avanzo, S.Covino, D. Fugazza, A. Melandri (INAF-OAB), on behalf of the REM team, report: We observed the field of GRB 181228A (Moss et al. GCN 23570) with the REM 60cm robotic telescope located at the ESO premise of La Silla (Chile). The observations were performed starting on 2018 December 28 at 02:54:10 UT (i.e. 53 seconds after the burst) and were carried in the g, r, i, z, J, H and K bands. In the first set of NIR images (carried out in the H band) we detect an uncatalogued, fading source at the following position: RA (J2000): 03:19:15.05 Dec (J2000): +13:12:06.7 +/- 0.5". This position is consistent with the enhanced XRT position reported by Beardmore et al. (GCN 23574). The NIR source we detect is not present in the 2MASS catalogue. We propose this source as the NIR afterglow of GRB 181228A. From preliminary photometry we estimate the following magnitudes: H = 14.3 +/- 0.1 at t-t0 = 122 s H = 16.4 +/- 0.3 at t-t0 = 601 s (Vega; calibrated against the 2MASS catalogue). At the same epochs, the source is not detected in the optical down to a 3sigma limiting magnitude of r ~ 18.0 (AB; calibrated against the pan-STARRS catalogue). This is consistent with the early optical non-detection reported by Zheng & Filippenko (GCN 23571).
GCN 23576 table
GRB_name GRB181228A
GCN_number 23576
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 23576 SUBJECT: GRB 181228A: Global MASTER Net OT detection DATE: 18/12/28 09:46:03 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, N.Tiurina, E. Gorbovskoy, V.Kornilov, P.Balanutsa, A.Kuznetsov, D. Vlasenko, D.Kobtsev (Lomonosov Moscow State University, SAI), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar), H. Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio of San Juan National University, Argentina) R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), A. Tlatov, V.Senik, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), O. Gress, N.M. Budnev, S. Yazev, O. Chuvalaev (Irkutsk State University, API) V. Yurkov, A. Gabovich, Yu. Sergienko (Blagoveschensk Educational State University) MASTER-OAFA robotic telescope (Global MASTER 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 GRB181228A (Moss et al., GCN #23570) 26 sec after notice time and 47 sec after trigger time at 2018-12-28 02:54:05 UT. On our first (10s exposure) set we found 1 optical transient within SWIFT XRT error-box (Beardmore et al., GCN #23574) brighter than 17.5. T-Tmid Date Time Expt. Ra Dec Mag s UTC s ---------|-------------------|------|-----------------|-----------------|------- 52 2018-12-28 02:54:05 10 ( 03h 19m 14.80s , +13d 12' 02".80 ) 17.0 The 5-sigma upper limit has been about 17.5 mag . Coordinate error ~2". The galactic latitude b = -35 deg., longitude l = 170 deg. The observations made on zenit distance = 49 deg.The moon (64 % bright part) below the horizon (The altitude of the Moon is -14 deg. ). The sun altitude is -29.6 deg. The object can be observed till 2018-12-28 06:59:09 The message may be cited.
GCN 23578 table
GRB_name GRB181228A
GCN_number 23578
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 23578 SUBJECT: GRB 181228A: Global MASTER-Net OT detection DATE: 18/12/28 11:56:32 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs N.Tyurina, V. Lipunov, E. Gorbovskoy, V.Kornilov, P.Balanutsa, A.Kuznetsov, D. Vlasenko, D.Kobtsev Lomonosov Moscow State University, SAI R. Podesta, C.Lopez, F. Podesta Observatorio Astronomico Felix Aguilar (OAFA) H. Levato Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias D. Buckley, South African Astronomical Observatory A. Tlatov, V.Senik, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory O. Gres, N.M. Budnev, S. Yazev, O. Chuvalaev, Irkutsk State University V. Yurkov, A. Gabovich, Yu. Sergienko, Blagoveschensk Educational State University, Blagoveschensk MASTER-OAFA robotic telescope (Global MASTER-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 GRB181228A (Moss et al., GCN #23570) 26 sec after notice time and 47 sec after trigger time at 2018-12-28 02:54:05 UT. On our first (10s exposure) set we found 1 optical transient within SWIFT XRT error-box (Beardmore et al., GCN #23574) brighter than 17.5. T-Tmid Date Time Expt. Ra Dec Mag s UTC s ---------|---------------------|-------|-----------------|-----------------|------- 52 2018-12-28 02:54:05 10 ( 03h 19m 14.80s , +13d 12' 02".8 ) 17.0 The 5-sigma upper limit has been about 17.5 mag . Coordinate error ~1". The galactic latitude b = -35 deg., longitude l = 170 deg. The observations made on zenit distance = 49 deg.The moon (64 % bright part) below the horizon (The altitude of the Moon is -14 deg. ). The sun altitude is -29.6 deg. The object can be observed till 2018-12-28 06:59:09 The message may be cited.
GCN 23579 table
GRB_name GRB181228A
GCN_number 23579
Detection_method Fermi GBM Det
t_trigger 2:53:14.960 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 23579 SUBJECT: GRB 181228A: Fermi GBM observation DATE: 18/12/28 14:35:02 GMT FROM: Elisabetta Bissaldi at INFN,Bari E. Bissaldi (Politecnico & INFN Bari) and P. Veres (UAH) report on behalf of the Fermi GBM Team: "At 02:53:14.96 UT on 28 December 2018, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 181228A (trigger 567658399 / 181228120), which was also detected by the Swift/BAT (Moss et al. 2018, GCN 23570). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 72 degrees. The GBM light curve consists of a two-peaked emission episode with a duration (T90) of about 18 s (50-300 keV). The time-averaged spectrum from T0 to T0+19 s is best fit by a Band function with Epeak = 182 +/- 8 keV, alpha = -0.82 +/- 0.03, and beta = -2.25 +/- 0.07. The event fluence (10-1000 keV) in this time interval is (2.56 +/- 0.05)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+15.6 s in the 10-1000 keV band is 16.0 +/- 0.4 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN 23580 table
GRB_name GRB181228A
GCN_number 23580
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 23580 SUBJECT: GRB 181228A: TSHAO optical upper limit DATE: 18/12/28 16:49:22 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Volnova (IKI), I. Reva (FAPHI), A. Pozanenko (IKI), E. Mazaeva (IKI), S. Belkin (IKI), A. Kusakin (FAPHI), M. Krugov (FAPHI) report on behalf of larger GRB follow-up collaboration: We observed the field of GRB 181228A (Moss et al., GCN 23570; Beardmoreet al., GCN 23574) with Zeiss-1000 1-m telescope of Tien Shan Astronomical Observatory starting on Dec. 28 (UT) 13:35:51. We do not detected the OT (D'Avanzo et al., GCN 23574; Lipunov et al. GCN 23576). Preliminary photometry of the field is following. Date UT start t-T0 Filter Exp. OT Err. UL (mid, days) (s) 2018-12-28 13:35:51 0.46359 R 21*120 n/d n/d 21.7 The photometry is based on nearby USNO-B1.0 star USNO-B1.0_id R2 1032-0046066 16.66
GCN 23581 table
GRB_name GRB181228A
GCN_number 23581
Detection_method Swift-UVOT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 23581 SUBJECT: GRB 181228A: Swift/UVOT Upper Limits DATE: 18/12/28 16:53:43 GMT FROM: Sam LaPorte at PSU GRB 181228A: Swift/UVOT Upper Limits S. J. LaPorte (PSU) and M. J. Moss (George Washington University) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 181228A 93 s after the BAT trigger (Moss et al., GCN Circ. 23570). No optical afterglow consistent with the XRT position (Moss et al. GCN Circ. 23570) 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 93 243 147 >20.4 u_FC 305 555 246 >20.6 white 93 1354 373 >21.0 v 634 1404 97 >19.1 b 561 1330 78 >20.5 u 305 1305 304 >20.5 w1 684 1280 39 >18.4 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.51 in the direction of the burst (Schlegel et al. 1998).
GCN 23583 table
GRB_name GRB181228A
GCN_number 23583
Detection_method Swift-BAT Det
ra 49.8310°
decl 13.2120°
Circular_text TITLE: GCN CIRCULAR NUMBER: 23583 SUBJECT: GRB 181228A: Swift-BAT refined analysis DATE: 18/12/28 18:56:14 GMT FROM: Amy Lien at GSFC A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), H. A. Krimm (NSF/USRA), C. B. Markwardt (GSFC), M. J. Moss (GWU), 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 181228A (trigger #879909) (Moss et al., GCN Circ. 23570). The BAT ground-calculated position is RA, Dec = 49.831, 13.212 deg which is RA(J2000) = 03h 19m 19.5s Dec(J2000) = +13d 12' 44.0" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 30%. The mask-weighted light curve shows a multi-peaked structure. The main structure starts at ~T-4 s and ends at ~T+20 s, with the highest peak occurs at ~ T+13 s. After the main pulse, there is another much weaker pulse that starts at ~ T+200 s and ends at ~T+340 s. T90 (15-350 keV) is 257.3 +- 102.5 sec (estimated error including systematics). The time-averaged spectrum from T-4.0 to T+337.9 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.45 +- 0.06. The fluence in the 15-150 keV band is 1.0 +- 0.03 x 10^-05 erg/cm2. The 1-sec peak photon flux measured from T+13.08 sec in the 15-150 keV band is 9.5 +- 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/879909/BA/
GCN 23584 table
GRB_name GRB181228A
GCN_number 23584
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 23584 SUBJECT: GRB 181228A: Swift-XRT refined Analysis DATE: 18/12/28 20:51:37 GMT FROM: Phil Evans at U of Leicester S. J. LaPorte (PSU), J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester), A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB) and M.J. Moss report on behalf of the Swift-XRT team: We have analysed 6.2 ks of XRT data for GRB 181228A (Moss et al. GCN Circ. 23570), from 88 s to 58.6 ks after the BAT trigger. The data comprise 405 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. 23574). The late-time light curve (from T0+12.9 ks) can be modelled with a power-law decay with a decay index of alpha=0.95 (+0.29, -0.28). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.60 (+/-0.05). The best-fitting absorption column is 3.30 (+0.28, -0.27) x 10^21 cm^-2, in excess of the Galactic value of 2.9 x 10^21 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.80 (+0.20, -0.19) and a best-fitting absorption column of 5.3 (+1.4, -1.2) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.6 x 10^-11 (6.8 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 5.3 (+1.4, -1.2) x 10^21 cm^-2 Galactic foreground: 2.9 x 10^21 cm^-2 Excess significance: 3.2 sigma Photon index: 1.80 (+0.20, -0.19) If the light curve continues to decay with a power-law decay index of 0.95, the count rate at T+24 hours will be 0.012 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.7 x 10^-13 (8.4 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/00879909. This circular is an official product of the Swift-XRT team.
GCN 23588 table
GRB_name GRB181228A
GCN_number 23588
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 23588 SUBJECT: GRB 181228A: Xinglong-2.16m optical upper limit DATE: 18/12/29 13:31:29 GMT FROM: Dong Xu at NAOC/CAS Z.P. Zhu, L.P. Xin, D. Xu, J.B. Zhang (NAOC), X. Zhang, J.H. Liu (XAO) report: We observed the field of GRB 181228A (Moss et al., GCN 23570) using the 2.16-m telescope located at Xinglong, Hebei, China, equipped with the BFOSC camera. We obtained 6x300s and 2x600s frames in I-band, starting at 13:04:00 UT on 2018-12-28, i.e., 10.18 hrs after the BAT trigger. The afterglow of GRB 181228A (e.g., Moss et al., GCN 23570; D'Avanzo et al., GCN 23575; Lipunov et al., GCN 23576) is not detected in our stacked image, down to a limiting magnitude of ~20.5 mag, calibrated with the nearby PanSTARRS field.
GCN 23590 table
GRB_name GRB181228A
GCN_number 23590
Detection_method MITSuME
Circular_text TITLE: GCN CIRCULAR NUMBER: 23590 SUBJECT: GRB 181228A: MITSuME Akeno optical upper limits DATE: 18/12/30 12:22:33 GMT FROM: Katsuhiro L. Murata at Nagoya U M. Oeda, K. L. Murata, R. Itoh, Y. Tachibana, S. Harita, K. Morita, K. Shiraishi, K. Iida, M. Niwano, R. Adachi, Y. Yatsu, and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration: We searched for the optical counterpart of GRB 181228A (M. J. Moss et al., GCN Circular #23570) 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 09:04:35.19 UT. We did not find any new point source within the enhanced XRT circle (A.P. Beardmore et al., GCN Circular #23574) in all three bands. We obtained following limits for the magnitudes. T0+[hour] MID-UT T-EXP[sec] g' Rc Ic ------------------------------------------------------------------------------------------------------- 6.188 13:04:51 25320 >19.1 >19.0 >18.6 ------------------------------------------------------------------------------------------------------- T0+ : Elapsed time after the burst T-EXP: Total Exposure time We used UCAC-4 catalog for flux calibration.
GCN 23593 table
GRB_name GRB181228A
GCN_number 23593
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 23593 SUBJECT: GRB 181228A: possible NOT optical detection DATE: 18/12/31 00:02:45 GMT FROM: Dong Xu at NAOC/CAS D. Xu (NAOC), D.B. Malesani (DAWN/NBI/DTU and DARK/NBI), J.P.U. Fynbo (DAWN/NBI and DAWN/DTU), M.I. Andersen (NBI), T. Pursimo (NOT) report: We observed the field of GRB 181228A (Moss et al., GCN 23570) using the 2.56m Nordic Optical Telescope (NOT) equipped with ALFOSC, starting at 23:56:20 UT on 2018-12-28, i.e., 21.05 hr after the BAT trigger. We obtained 3x300s unfiltered frames and 3x300s frames in the Sloan i-band. There is a weak detection in our stacked image at the REM position (D'Avanzo et al., GCN 23575), thus also being consistent with the enhanced XRT error circle (Beardmore et al., GCN 23574). The above position is not consistent with that of MASTER OT reported in Lipunov et al. (GCN 23576). The NOT source has m(i)~25.0+/-0.5, calibrated with nearby PanSTARRS stars, and thus it could be the optical counterpart of GRB 181228A.
GCN 23594 table
GRB_name GRB181228A
GCN_number 23594
Detection_method Swift-BAT Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 23594 SUBJECT: GRB 181228A: Global MASTER Net OT is the same REM IR transient DATE: 18/12/31 09:57:40 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, N.Tiurina, E. Gorbovskoy, V.Kornilov, P.Balanutsa, A.Kuznetsov, D. Vlasenko, D.Kobtsev (Lomonosov Moscow State University, SAI), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar), H. Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio of San Juan National University, Argentina) R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), A. Tlatov, V.Senik, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), O. Gress, N.M. Budnev, S. Yazev, O. Chuvalaev (Irkutsk State University, API) V. Yurkov, A. Gabovich, Yu. Sergienko (Blagoveschensk Educational State University) The optical source detected by MASTER (Lipunov et al., GCN 23576) insidet Swift BAT GRB 181228A error box (Moss et al., GCN 23570) regardless of the infrared telescope REM (D'Avanzo et al., GCN 23575) is one and the same source. The difference in coordinates is less than 3 sigma. Our coordinates are of course rather rough, since the source itself is very weak. Let me remind you that the pixel MASTER is equal to 2.5 arcsec. OT (not infrared) discovered by MASTER is disappear on late imeges! HNY! The message may be cited.
GCN 23596 table
GRB_name GRB181228A
GCN_number 23596
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 23596 SUBJECT: GRB 181228A: Mondy and AbAO optical upper limits DATE: 18/12/31 17:37:10 GMT FROM: Alexei Pozanenko at IKI, Moscow S. Belkin (IKI), A. Pozanenko (IKI), E. Klunko (ISTP), R. Ya. Inasaridze (AbAO), E. Mazaeva (IKI), A. Volnova (IKI), V. R. Ayvazian (AbAO), G. V. Kapanadze (AbAO) report on behalf of the IKI GRB-FuN: We observed the field of GRB 181228A (Moss et al., GCN 23570; Beardmore et al., GCN 23574) with AZT-33IK telescope of Sayan observatory (Mondy) starting on Dec. 28 (UT) 13:48:11 in I-filter, and AS-32 telescope of Abastumani Observatory (AbAO) on Dec. 28 (UT) 15:13:46 in R-filter. We do not detected the afterglow (D'Avanzo et al., GCN 23575; Lipunov et al. GCN 23576; Xu et al., GCN 23593). Preliminary photometry of the field is following. Date UT start t-T0 Filter Exp. OT Err. UL (mid, days) (s) 2018-12-28 13:48:11 0.47494 I 30*120 n/d n/d 23.8 2018-12-28 15:13:46 0.54879 R 63*60 n/d n/d 21.0 The photometry is based on nearby USNO-B1.0 stars USNO-B1.0_id R2 I2 1032-0046066 16.66 16.08 1031-0043284 16.04 15.36
GCN 23669 table
GRB_name GRB181228A
GCN_number 23669
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 23669 SUBJECT: GRB 181228A: FRAM-ORM optical limit DATE: 19/01/10 07:26:40 GMT FROM: Martin Jelinek at Astro.Inst-AVCR,Ondrejov Martin Jelinek and Jan Strobl (ASU CAS Ondrejov, CZ), Martin Masek, Petr Janecek, Sergey Karpov, Jakub Jurysek, Jan Ebr, Ronan Cunniffe, Petr Travnicek and Michael Prouza (Institute of Physics, Prague, CZ) report: The 25cm robotic telescope FRAM-ORM at La Palma (Spain) reacted robotically to the alert of GRB181228A (Moss et al, GCNC 23570), obtaining a series of 20s R-band images starting at 02:53:51.1UT, i.e. 34s post trigger. We do not detect any new source in comparison to USNO-B1.0 catalog neither in single images (3-sigma limit R>~17.1) nor in a combined 20x20s frame (mean exp time 269s post trigger, 3-sigma limit R>~18.7). Martin Jelínek, +420602105255, +34617840945, lascaux.asu.cas.cz/mates Astronomický ústav AVČR, Ondřejov