GRB 231205A
GCN Circular 35263
Subject
GRB 231205A: Fermi GBM Final Real-time Localization
Date
2023-12-05T02:35:45Z (2 years 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 SHORT GRB
At 02:25:11 UT on 5 Dec 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231205A (trigger 723435916.407408 / 231205101).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 206.1, Dec = 22.8 (J2000 degrees, equivalent to J2000 13h 44m, 22d 48'), with a statistical uncertainty of 3.1 degrees.
The angle from the Fermi LAT boresight is 79.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231205101/quicklook/glg_skymap_all_bn231205101.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231205101/quicklook/glg_healpix_all_bn231205101.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231205101/quicklook/glg_lc_medres34_bn231205101.gif
GCN Circular 35266
Subject
GRB 231205A: GECAM-B detection of a short burst
Date
2023-12-05T03:48:51Z (2 years ago)
From
tanwj@ihep.ac.cn
Via
Web form
GRB 231205A: GECAM-B detection of a short burst
Wenjun Tan, Shaolin Xiong, report on behalf of the GECAM team:
GECAM-B was triggered in-flight by a short burst, GRB 231205A
at 2023-12-05T02:25:11.450 UTC(T0), which was also observed by
Fermi/GBM (Fermi/GBM team, GCN 35263).
According to the realtime alert data of GECAM-B, this burst consists
of one bright short pulse followed by weaker emission with a total
duration (T90) of about ~0.3 sec (30-1020 keV).
Using the automatic on-ground localization pipeline with the realtime alert data,
GECAM-B localized this burst to the following position (J2000):
Ra: 202.8 deg
Dec: 26.8 deg
Err: 6.1 deg (1-sigma, statistical only)
GECAM location is consistent with that of Fermi/GBM within the error.
The time-averaged spectrum of GECAM-B realtime data from about T0-0.05 s to T0 could be
adequately fit by a cut-off power-law with a fluence about 1.10E-6 erg/cm^2 in 20-1000 keV.
We note that these results are based on realtime alert data and thus very preliminary.
Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor
(GECAM) mission originally consists of two microsatellites (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 35268
Subject
GRB 231205A: joint location of multiple instruments by ETJASMIN
Date
2023-12-05T16:33:30Z (2 years ago)
From
yqzhang_cl@163.com
Via
Web form
Yanting Zhang, Shaolin Xiong, Yue Huang, Shuo Xiao, Xiaoyun Zhao, Ping Wang,
report on behalf of the GECAM team:
The short burst, GRB 231205A, has been detected by GECAM-B (Tan et al., GCN 35266), Fermi/GBM (Fermi/GBM team, GCN 35263) and INTEGRAL/SPI-ACS. With the ETJASMIN pipeline (Energetic Transients joint analysis system for Multi-INstrument, Xiao et al., MNRAS, 514, 2397, 2022) and the realtime data of GECAM-B, INTEGRAL/SPI-ACS and Fermi/GBM, we did a low-latency joint location for this burst.
Firstly, we applied the Li-CCF method (Xiao et al., ApJ, 920, 43, 2021) to the realtime high temporal resolution (~1 ms) light curve of GECAM-B and the low-latency public 50 ms light curve of INTEGRAL/SPI-ACS, and derived the triangulation location as the following annuli:
--------------------------------------------------------------------------------------------------
Annulus Ra (deg) Dec (deg) Radius (deg) Radius-Error (deg, 3sigma)
GECAM-B + SPI-ACS 209.519 59.889 40.961 1.272
--------------------------------------------------------------------------------------------------
Then, we combined this annulus location, the stand-alone locations provided by GECAM-B (Tan et al., GCN 35266) and Fermi/GBM (Fermi/GBM team, GCN 35263), as well as the Earth occultation of these instruments, and derived a refined location, which is much smaller than stand-alone ones.
This refined location (~3 sigma region) could be approximately described by a polygon region,
whose center and corners are:
--------------------------------------
Ra (deg) Dec (deg)
Center 205.313 19.155
Corner1 215.859 19.155
Corner2 209.883 18.724
Corner3 202.148 18.871
Corner4 194.766 20.427
Corner5 205.313 19.524
--------------------------------------
For this refined location, the sky map and probability data could be found at:
Sky map: http://twiki.ihep.ac.cn/pub/GECAM/GRBList/GRB231205A-jointLoc-skymap-v01.png
Data file: http://twiki.ihep.ac.cn/pub/GECAM/GRBList/GRB231205A-jointLoc-healpix-v01.fits
ETJASMIN is developed for joint observation of high energy transients by the GECAM team.
We acknowledge the public data of Fermi/GBM and INTEGRAL/SPI-ACS.
GCN Circular 35277
Subject
GRB 231205A: DDOTI Upper Limits on the Afterglow
Date
2023-12-06T01:21:44Z (2 years ago)
From
Kin O. C. L. Mendoza at Instituto de Astronoma, UNAM <koclopez@astro.unam.mx>
Via
legacy email
Océlotl Lopez (UNAM), Alan M. Watson (UNAM), Rosa L. Becerra (UNAM),
Margarita Pereyra (UNAM), Nat Butler (ASU), Simone Dichiara (Penn state
university), Diego Gonzalez (UNAM), William H. Lee (UNAM), Alexander
Kutyrev (GSFC/UMD), Srihari Ravi (ASU) and Eleonora Troja (Tor Vergara
Roma) report:
We observed the field of the Fermi GBM GRB 231205A (Fermi GBM Team, GCN
Circ. 35263) with the DDOTI wide-field imager at the Observatorio
Astronómico Nacional on Sierra San Pedro Mártir (
http://ddoti.astroscu.unam.mx) from 2023-12-05 12:55:13 to 13:10:57 UTC
(10.50 to 11.75 hours after the trigger).
We observed a region of 7 degrees in RA by 7 degrees in declination
centered on the Fermi GBM Final Position of RA = 206.1 and Dec = 22.8
(J2000 degrees). This region contains 1 instrumental field or about 49
square degrees. We obtained 13.6 minutes of exposure per instrumental field
in the w filter. We obtained AB photometry by calibration against the APASS
catalog.
We detect no likely candidates for the afterglow to our 10-sigma upper
limits of w = 18.89-19.41 (inter-quartile).
We thank the staff of the Observatorio Astronómico Nacional on San Pedro
Mártir.
GCN Circular 35304
Subject
IPN triangulation of GRB 231205A
Date
2023-12-07T16:20:39Z (2 years ago)
From
Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>
Via
legacy email
A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin
on behalf of the HEND/Mars Odyssey team,
D. Svinkin, D. Frederiks, A. Ridnaia, A. Lysenko,
and T. Cline on behalf of the Konus-Wind team,
A. Goldstein, M.S. Briggs, C. Wilson-Hodge,
and E. Burns on behalf of the Fermi GBM team,
E. Bozzo and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,
S.-L. Xiong, Y. Huang, X.-Y. Zhao, and P. Wang
on behalf of the GECAM team,
and
W. Boynton, C. Fellows, K. Harshman, H. Enos, R. Starr,
and A.S. Gardner on on behalf of the GRS-Odyssey GRB team,
report:
The bright, short-duration GRB 231205A
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 35263;
GECAM-B detection: Tan et al., GCN Circ. 35266;
ETJASMIN localization: Zhang et al., GCN Circ. 35268)
has been detected by Fermi-GBM (trigger 723435916), Konus-Wind,
INTEGRAL (SPI-ACS), GECAM-B (GRD), and Mars-Odyssey (HEND)
so far, at about 8711 s UT (02:25:11).
We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
---------------------------------------------
RA(2000), deg Dec(2000), deg
---------------------------------------------
Center:
202.936 (13h 31m 45s) +17.932 (+17d 55' 55")
Corners:
203.258 (13h 33m 02s) +18.299 (+18d 17' 58")
202.683 (13h 30m 44s) +17.694 (+17d 41' 38")
202.612 (13h 30m 27s) +17.557 (+17d 33' 25")
203.188 (13h 32m 45s) +18.166 (+18d 09' 57")
---------------------------------------------
The error box area is 119 sq. arcmin, and its maximum
dimension is 58 arcmin (the minimum one is 2.4 arcmin).
The Sun distance was 62 deg.
This localization may be improved.
The IPN localization is consistent with, but reduces the area of,
the Fermi-GBM final localization and ETJASMIN localization.
A triangulation map and HEALPix FITS file are posted at
http://www.ioffe.ru/LEA/GRBs/GRB231205_T08710/IPN
The Konus-Wind time history and spectrum will be given
in a forthcoming GCN Circular.
GCN Circular 35402
Subject
GRID detection of GRB 231205A
Date
2023-12-19T12:34:43Z (a year ago)
From
GRID Student Team at Tsinghua University <grid@tsinghua.edu.cn>
Via
Web form
Chenyu Wang, Zirui Yang, Longhao Li and Songyu Shen report on behalf of the GRID Collaboration:
GRID-07 reports the detection of the short-duration GRB 231205A, which was also detected by Fermi/GBM and GECAM-B(GCN Circular 35263, 35266).
The event was triggered with GRID on 2023-12-05 at 02:25:11.2 UTC. The measured burst duration (T90) in the 30-2000 keV range is approximately 0.4 ± 0.1 seconds.
The GRID light curve of this event can be found at https://mirrors.tuna.tsinghua.edu.cn/GRID/data/GRID-GCN/GRB231205A/GRID_231205A_ltcv.pdf.
GRID is a student-led project to monitor the transient gamma-ray sky with multiple detectors onboard different nanosatellites in the era of multi-messenger astronomy. For more information about GRID, please refer to the following references: https://doi.org/10.1007/s10686-019-09636-w and https://doi.org/10.1007/s10686-021-09819-4.