GRB 251214A
GCN Circular 43107
Subject
GRB 251214A: AstroSat CZTI detection
Date
2025-12-15T06:13:10Z (a day ago)
From
Gaurav Waratkar at Caltech <gauravwaratkar@iitb.ac.in>
Via
Web form
A. Goyal (IITB), A. Arya (IITB), M. Tembhurnikar (IUCAA), S. Salunke (IUCAA), Harsha K. H. (IUCAA), G. Waratkar (Caltech/IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:
Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of GRB 251214A which was also detected by Fermi GBM (Fermi GBM Team, GCN Circ. 43086). We detect only the brighter shorter-duration part of the burst as seen in the GBM lightcurve because the source location was at an angle of 110 deg from the pointing axis of AstroSat CZTI.
The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve peaks at 2025-12-14 00:11:15.25 UTC. The measured peak count rate associated with the burst is 274 (+153, -45) counts/s above the background in the combined data of all quadrants, with a total of 134 (+124, -33) counts. The local mean background count rate was 269 (+5, -23) counts/s. Using cumulative rates, we measure a T90 of 1.4 (+0.2, -1.0) s.
The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2025-12-14 00:11:14.91 UTC. The measured peak count rate associated with the burst is 347 (+66, -71) counts/s above the background in the combined data of all quadrants, with a total of 418 (+226, -230) counts. The local mean background count rate was 1283 (+6, -7) counts/s. Due to the intrinsic 1 s binning of veto data, we cannot reliably estimate a T90 for our detection.
CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.
CZTI GRB detections are reported regularly on the payload site at:
http://astrosat.iucaa.in/czti/?q=grb
GCN Circular 43101
Subject
GRB 251214A: GECAM-B observation of a likely long burst
Date
2025-12-15T01:08:35Z (a day ago)
Edited On
2025-12-15T14:34:30Z (13 hours ago)
From
Xinghao Luo at SVOM/GRN <2952704891@qq.com>
Edited By
Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of Xinghao Luo at SVOM/GRN <2952704891@qq.com>
Via
Web form
Xing-Hao Luo, Chen-Wei Wang, Shao-Lin Xiong (IHEP) report on behalf of GECAM team:
GECAM-B was triggered on-ground by GRB 251214A, at 2025-12-14T00:11:15.200 UTC (denoted as T0), which is also detected by Fermi/GBM (Fermi GBM team, GCN #43085).
According to the GECAM-B light curves in about 70-6000 keV, this burst mainly consists of multiple pulses with a duration (T90) of 5.0 +1.0/-2.5s.
The GECAM-B light curve can be found here:
https://www.bursthub.cn//admin/static/gecambgrb251214A.png
Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) mission originally consists of two micro-satellites (GECAM-A and GECAM-B) launched in Dec. 2020. As the third member of GECAM constellation, GECAM-C was launched onboard SATech-01 experimental satellite in July 2022. GECAM mission is funded by the Chinese Academy of Sciences (CAS).
GCN Circular 43086
Subject
Fermi GRB 251214A: Global MASTER-Net observations report
Date
2025-12-14T00:45:21Z (2 days ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
Via
email
V.Lipunov, E.Gorbovskoy, A.Kuznetsov, K.Zhirkov, I.Panchenko, N.Tiurina, P.Balanutsa, V.Topolev, D.Vlasenko,
G.Antipov, A.Sankovich, Yu.Tselik, Ya.Kechin, V.Senik, A.Chasovnikov, K.Labsina, I. Gorbunov (Lomonosov MSU),
O.Gress, N.Budnev (ISU),
C.Francile, F. Podesta, R.Podesta, E. Gonzalez (Observatorio Astronomico Felix Aguilar (OAFA),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
A.Sosnovskij (CrAO),
A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity),
D.Buckley (SAAO),
R.Rebolo (The Instituto de Astrofisica de Canarias),
L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory)
MASTER-Tunka robotic telescope [1] located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the Fermi GRB 251214A ( Fermi GBM team, GCN 43085) errorbox 201 sec after notice time and 238 sec after trigger time at 2025-12-14 00:15:13 UT, with upper limit up to 14.7 mag. Observations started at twilight. The observations began at zenith distance = 44 deg. The sun altitude is -7.0 deg.
The galactic latitude b = 52 deg., longitude l = 219 deg.
Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=3070442
We obtain a following upper limits.
Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________
239 | 2025-12-14 00:15:13 | MASTER-Tunka | (10h 12m 20.99s , +17d 57m 22.4s) | C | 1 | 14.4 |
240 | 2025-12-14 00:15:13 | MASTER-Tunka | (10h 12m 21.00s , +17d 57m 22.4s) | C | 3 | 14.7 | Coadd
239 | 2025-12-14 00:15:13 | MASTER-Tunka | (10h 11m 48.16s , +18d 04m 24.3s) | C | 1 | 14.2 |
245 | 2025-12-14 00:15:18 | MASTER-Tunka | (10h 12m 21.00s , +17d 57m 22.3s) | C | 1 | 14.3 |
245 | 2025-12-14 00:15:18 | MASTER-Tunka | (10h 11m 48.16s , +18d 04m 24.2s) | C | 1 | 14.1 |
250 | 2025-12-14 00:15:24 | MASTER-Tunka | (10h 12m 21.00s , +17d 57m 22.0s) | C | 1 | 14.0 |
250 | 2025-12-14 00:15:24 | MASTER-Tunka | (10h 11m 48.17s , +18d 04m 24.0s) | C | 1 | 14.0 |
256 | 2025-12-14 00:15:30 | MASTER-Tunka | (10h 11m 48.17s , +18d 04m 23.6s) | C | 1 | 13.8 |
256 | 2025-12-14 00:15:30 | MASTER-Tunka | (10h 12m 21.00s , +17d 57m 21.9s) | C | 1 | 14.0 |
257 | 2025-12-14 00:15:30 | MASTER-Tunka | (10h 12m 21.00s , +17d 57m 22.0s) | C | 3 | 14.4 | Coadd
262 | 2025-12-14 00:15:36 | MASTER-Tunka | (10h 12m 21.01s , +17d 57m 21.7s) | C | 1 | 13.9 |
262 | 2025-12-14 00:15:36 | MASTER-Tunka | (10h 11m 48.17s , +18d 04m 23.7s) | C | 1 | 13.8 |
267 | 2025-12-14 00:15:41 | MASTER-Tunka | (10h 11m 48.18s , +18d 04m 23.4s) | C | 1 | 13.8 |
267 | 2025-12-14 00:15:41 | MASTER-Tunka | (10h 12m 21.02s , +17d 57m 21.5s) | C | 1 | 13.9 |
273 | 2025-12-14 00:15:47 | MASTER-Tunka | (10h 12m 21.05s , +17d 57m 21.5s) | C | 1 | 13.9 |
274 | 2025-12-14 00:15:47 | MASTER-Tunka | (10h 12m 21.05s , +17d 57m 21.5s) | C | 3 | 14.4 | Coadd
273 | 2025-12-14 00:15:47 | MASTER-Tunka | (10h 11m 48.20s , +18d 04m 23.3s) | C | 1 | 13.5 |
278 | 2025-12-14 00:15:52 | MASTER-Tunka | (10h 12m 21.04s , +17d 57m 21.1s) | C | 1 | 14.0 |
279 | 2025-12-14 00:15:52 | MASTER-Tunka | (10h 11m 48.20s , +18d 04m 22.9s) | C | 1 | 13.7 |
285 | 2025-12-14 00:15:58 | MASTER-Tunka | (10h 12m 21.05s , +17d 57m 21.1s) | C | 1 | 13.9 |
285 | 2025-12-14 00:15:58 | MASTER-Tunka | (10h 11m 48.23s , +18d 04m 22.8s) | C | 1 | 13.8 |
290 | 2025-12-14 00:16:04 | MASTER-Tunka | (10h 12m 21.06s , +17d 57m 20.6s) | C | 1 | 13.8 |
291 | 2025-12-14 00:16:04 | MASTER-Tunka | (10h 12m 21.06s , +17d 57m 20.6s) | C | 3 | 14.3 | Coadd
291 | 2025-12-14 00:16:04 | MASTER-Tunka | (10h 11m 48.25s , +18d 04m 22.6s) | C | 1 | 13.8 |
296 | 2025-12-14 00:16:09 | MASTER-Tunka | (10h 12m 21.03s , +17d 57m 20.4s) | C | 1 | 13.8 |
296 | 2025-12-14 00:16:09 | MASTER-Tunka | (10h 11m 48.23s , +18d 04m 22.2s) | C | 1 | 13.5 |
302 | 2025-12-14 00:16:15 | MASTER-Tunka | (10h 12m 21.04s , +17d 57m 20.4s) | C | 1 | 13.8 |
302 | 2025-12-14 00:16:15 | MASTER-Tunka | (10h 11m 48.25s , +18d 04m 22.3s) | C | 1 | 13.5 |
Filter C is a clear (unfiltred) band.
The observation and reduction will continue.
The message may be cited.
[1] - V.M. Lipunov, V.G. Kornilov, E.S. Gorbovskoy, N.A. Tiurina & A.S.Kuznetsov, 2023, Astronomical Robotic Networks and Operative Multichanel Astrophysics, Lomonosov MSU PRESS, 591pp.
http : // www.pereplet.ru/lipunov/625.html
GCN Circular 43085
Subject
GRB 251214A: Fermi GBM Final Real-time Localization
Date
2025-12-14T00:21:49Z (2 days ago)
From
Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>
Via
email
The Fermi GBM team reports the detection of a likely LONG GRB
At 00:11:15 UT on 14 Dec 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 251214A (trigger 787363880.165798 / 251214008).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 152.4, Dec = 17.9 (J2000 degrees, equivalent to J2000 10h 09m, 17d 53'), with a statistical uncertainty of 4.9 degrees.
The angle from the Fermi LAT boresight is 61.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251214008/quicklook/glg_skymap_all_bn251214008.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/bn251214008/quicklook/glg_healpix_all_bn251214008.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251214008/quicklook/glg_lc_medres34_bn251214008.gif