GCN Circular 38271
Subject
GRB 241115B: Fermi GBM Observation
Date
2024-11-18T20:06:33Z (a month ago)
From
oindabimukherjee@gmail.com
Via
Web form
O. Mukherjee (USRA), S. Bala (USRA) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:
"At 18:07:25.97 UT on 15 November 2024, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 241115B (trigger 753386850/241115755).
which was also detected by Swift/BAT-NITRATES (Ronchini et al. 2024, GCN 38260).
The Fermi GBM on-ground location was reported in GCN 38241.
The angle from the Fermi LAT boresight is 97 degrees.
The GBM light curve consists of multiple peaks with a duration (T90)
of about 71 s (50-300 keV). The time-averaged spectrum
from T0-8.9 to T0+70.9 s is best fit by
a power law function with an exponential high-energy cutoff.
The power law index is -1.04 +/- 0.09 and the cutoff energy,
parameterized as Epeak, is 833 +/- 263 keV.
The event fluence (10-1000 keV) in this time interval is
(9.9 +/- 0.5)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+14 s in the 10-1000 keV band is 3.2 +/- 0.2 ph/s/cm^2.
A Band function fits the spectrum equally well with
Epeak = 780 +/- 272 keV, alpha = -1.03 +/- 0.09 and beta = -2.65 +/- 1.39.
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/"