GRB 231118B
GCN Circular 35111
Subject
GRB 231118B: Fermi GBM Final Real-time Localization
Date
2023-11-18T22:44:35Z (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 22:34:14 UT on 18 Nov 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231118B (trigger 722039659.86232 / 231118940).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 348.9, Dec = 33.6 (J2000 degrees, equivalent to J2000 23h 15m, 33d 36'), with a statistical uncertainty of 1.0 degrees.
The angle from the Fermi LAT boresight is 83.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231118940/quicklook/glg_skymap_all_bn231118940.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/bn231118940/quicklook/glg_healpix_all_bn231118940.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231118940/quicklook/glg_lc_medres34_bn231118940.gif
GCN Circular 35112
Subject
GRB 231118B: BALROG localization (Fermi Trigger 722039659 / GRB 231118940)
Date
2023-11-18T23:42:44Z (2 years ago)
From
Jochen Greiner at MPE <jcgrog@mpe.mpg.de>
Via
email
T. Preis, B. Biltzinger, J. Burgess & J. Greiner (all MPE Garching) report:
The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
722039659 at 22:34:14 on 18 Nov. 2023 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).
The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 346.7+/-0.8 deg
Decl.(2000.0) = 33.9+/-1.2 deg
We estimate an additional systematic error of 2 deg.
Further details are available at:
https://grb.mpe.mpg.de/grb/GRB231118940/
The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB231118940/healpix
The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB231118940/json
GCN Circular 35132
Subject
GRB 231118B: Fermi GBM observation
Date
2023-11-20T03:32:59Z (2 years ago)
From
Lorenzo Scotton at UAH <lscottongcn@outlook.com>
Via
Web form
C. de Barra (UCD) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:
"At 22:34:14.86 UT on 18 November 2023, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 231118B (trigger 722039659/231118940).
The Fermi GBM Final Real-time Localization is reported in GCN 35111.
The angle from the Fermi LAT boresight is 83 degrees.
The GBM light curve consists of a single bright peak
with a duration (T90) of about 6 s (50-300 keV).
The time-averaged spectrum from T0+0.1 to T0+7.9 s
is best fit by a Band function with Epeak = 127.9 +/- 3.4 keV,
alpha = -0.36 +/- 0.04, and beta = -2.89 +/- 0.13
The event fluence (10-1000 keV) in this time interval is
(1.3 +/- 0.1)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+2.7 s in the 10-1000 keV band is 21.7 +/- 0.4 ph/s/cm^2.
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 Circular 35137
Subject
GRB 231118B: CALET Gamma-Ray Burst Monitor detection
Date
2023-11-20T15:07:18Z (2 years ago)
From
Yuta Kawakubo at Louisiana State University <kawakubo1@lsu.edu>
Via
Web form
S. Nakahira (JAXA), A. Yoshida, T. Sakamoto, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), Y. Asaoka (ICRR),
S. Torii, Y. Akaike, K. Kobayashi (Waseda U), Y. Shimizu,
T. Tamura (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 231118B (Fermi GBM Final Real-time Localization:
Fermi GBM team, GCN Circ. 35111; BALROG localization: Preis
et al., GCN Circ 35112; Fermi GBM observation: de Barra et al.,
GCN Circ 35132) triggered the CALET Gamma-ray Burst
Monitor (CGBM) at 22:34:15.15 UTC on 18 November 2023
(http://cgbm.calet.jp/cgbm_trigger/flight/1384381978/index.html).
The burst signal was seen by HXM1 and SGM detectors. No real-time
CGBM GCN notice was distributed about this trigger because
the real-time communication from the ISS was off (loss of signal).
The burst light curve shows a single pulse that starts
at T-0.7 sec, peaks at T+2.8 sec, and ends at T+6.5 sec.
The T90 and T50 durations measured by the SGM data are 5.6 +/- 0.3 sec
and 2.4 +/- 0.1 sec (40-1000 keV), respectively.
The ground-processed light curve is available at
http://cgbm.calet.jp/cgbm_trigger/ground/1384381978
The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at Waseda University.