GRB 231204A
GCN Circular 35258
Subject
GRB 231204A: Fermi GBM Final Real-time Localization
Date
2023-12-04T20:10:25Z (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 LONG GRB
At 20:00:03 UT on 4 Dec 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231204A (trigger 723412808.99994 / 231204833).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 324.4, Dec = 54.7 (J2000 degrees, equivalent to J2000 21h 37m, 54d 42'), with a statistical uncertainty of 2.4 degrees.
The angle from the Fermi LAT boresight is 19.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231204833/quicklook/glg_skymap_all_bn231204833.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/bn231204833/quicklook/glg_healpix_all_bn231204833.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231204833/quicklook/glg_lc_medres34_bn231204833.gif
GCN Circular 35267
Subject
GRB 231204A: AstroSat CZTI detection
Date
2023-12-05T14:16:15Z (2 years ago)
From
Gaurav Waratkar at IIT Bombay <gauravwaratkar@iitb.ac.in>
Via
Web form
G. Waratkar (IITB), P. K. Navaneeth (IUCAA), 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 the long-duration GRB 231204A which was also detected by Fermi-GBM (Fermi GBM Team, GCN Circ. 35258).
The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve peaks at 2023-12-04 20:00:04.5 UTC. The measured peak count rate associated with the burst is 230.7 (+39.0, -34.4) counts/s above the background in the combined data of all quadrants, with a total of 1319 (+234, -237) counts. The local mean background count rate was 347.5 (+2.1, -2.9) counts/s. Using cumulative rates, we measure a T90 of 13 (+7, -5) s.
It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-12-04 20:00:06.6 UTC. The measured peak count rate is 873.2 (+83.1, -58.1) counts/s above the background in the combined Veto data of all quadrants, with a total of 6070 (+508, -547) counts. The local mean background count rate was 1532.5 (+4.8, -5.7) counts/s. We measure a T90 of 12 (+8, -3) s from the cumulative Veto light curve.
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 35272
Subject
GRB 231204A: CALET Gamma-Ray Burst Monitor detection
Date
2023-12-05T19:10:01Z (2 years ago)
From
Yuta Kawakubo at Louisiana State University <kawakubo1@lsu.edu>
Via
Web form
T. Tamura (Kanagawa U), A. Yoshida, T. Sakamoto, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (JAXA),
Y. Asaoka (ICRR), S. Torii, Y. Akaike, K. Kobayashi (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:
The long GRB 231204A (Fermi GBM Final Real-time Localization:
Fermi GBM team, GCN Circ. 35258; AstroSat CZTI detection:
Waratkar et al., GCN Circ. 35267) triggered the CALET Gamma-ray
Burst Monitor (CGBM) at 20:00:00.75 UTC on 4 December 2023
(http://cgbm.calet.jp/cgbm_trigger/flight/1385755095/).
The burst signal was seen by only the SGM detector.
The burst light curve shows a weak pulse that starts
at T+3.1 sec, peaks at T+4.1 sec, and ends at T+7.9 sec.
The T90 and T50 durations measured by the SGM data are 4.5 +/- 0.5 sec
and 2.5 +/- 0.1 sec (40-1000 keV), respectively.
The ground-processed light curve is available at
http://cgbm.calet.jp/cgbm_trigger/ground/1385755095/index.html
The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at Waseda University.
GCN Circular 35274
Subject
GRB 231204A: Glowbug gamma-ray detection
Date
2023-12-05T20:09:43Z (2 years ago)
From
C.C. Cheung at Naval Research Lab <Teddy.Cheung@nrl.navy.mil>
Via
Web form
C.C. Cheung, M. Kerr, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:
The Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of GRB 231204A, which was also detected by Fermi/GBM, AstroSat/CZTI, and CALET (GCN 35258, 35267, 35272).
Using an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-12-04 20:00:02.808 with a duration of 11.3 s and a total significance of about 27.2 sigma. The light curve comprises a dominant triple-peaked structure from T0 to ~T0+6s and a fainter pulse at ~T0+9s.
Using a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=0.6 and a cutoff energy ("Epeak") of 619 keV. The modeled 10-10000 keV fluence is 1.3e-05 erg/cm^2.
The analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.
Glowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC. It was launched on 2023 March 15 aboard the Department of Defense Space Test Program’s STP-H9 to the ISS. The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.
[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959
[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O
[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006
Distribution Statement A: Approved for public release. Distribution is unlimited.
GCN Circular 35371
Subject
GRB 231204A: VZLUSAT-2 detection
Date
2023-12-16T11:17:21Z (a year ago)
From
Marianna Dafčíková at Masaryk University <500025@mail.muni.cz>
Via
Web form
M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), H. Takahashi (Hiroshima U.), F. Munz , M. Topinka, F. Hroch, N. Husarikova, J.-P. Breuer (Masaryk U.), J. Hudec, J. Kapus, M. Frajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo (Needronix), G. Galgoczi (Wigner Research Center/Eotvos U.), N. Uchida (ISAS/JAXA), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), Y. Fukazawa, K. Hirose, H. Matake (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), K. Torigoe (Hiroshima U.), P. Svoboda, V. Daniel, J. Dudas, M. Junas, J. Gromes (VZLU), I. Vertat (FEL ZCU) -- the VZLUSAT-2/GRB payload collaboration.
The long duration GRB 231204A (Fermi/GBM detection: GCN 35258; AstroSat detection: GCN 35267; CALET/CGBM detection: GCN 35272; Glowbug detection: GCN 35274; Konus/WIND detection at 2023-12-04 20:00:04.344 UT; INTEGRAL/SPI-ACS peak detection at 2023-12-04 ~20:00:05 UT) was detected by the GRB detectors on board of the VZLUSAT-2 3U CubeSat (https://www.vzlusat2.cz/en/).
The data acquisition was performed by the GRB detector units no. 0 and no. 1. The detection was confirmed at the peak time 2023-12-04 20:00:07 UTC. The T90 duration is 5 s and the significance during T90 reaches 6 sigma (10 sigma) for detector unit no. 0 (no. 1).
The light curve obtained by VZLUSAT-2 is available here:
https://vzlusat2.konkoly.hu/static/share/GRB231204A_GCN_VZLUSAT2.pdf
All VZLUSAT-2 detections are listed at: https://monoceros.physics.muni.cz/hea/VZLUSAT-2/
The GRB detectors on VZLUSAT-2 are a demonstration payload for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). Two GRB modules of VZLUSAT-2 are placed in a perpendicular manner and each consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~30 keV to ~1000 keV. VZLUSAT-2 was launched on 2022 January 13 from Cape Canaveral.