GRB 211124A: Fermi GBM Observation
Abstract
"At 02:29:53.56 UT on 24 November 2021, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 211124A (trigger 659413798 / 211124104), The results from Swift/BAT + NITRATES (DeLaunay et al. 2021, GCN 31113) are consistent with a burst coming from out of the FOV, which is also consistent with the GBM in-flight location. The GBM location, using the GBM trigger data, is RA = 94.967, DEC = -61.433 (J2000 degrees, equivalent to 06h 20m, -61d 26'), with a statistical uncertainty of 5.98 degrees (radius, 1-sigma containment, statistical only; there is additionally a systematic error which we have characterized as a core-plus-tail model, with 90% of GRBs having a 3.7 deg error and a small tail suffering a larger than 10 deg systematic error. [Connaughton et al. 2015, ApJS, 216, 32] ). The angle from the Fermi LAT boresight at the GBM trigger time is 45.00 degrees. The GBM light curve shows two peaks with a duration (T90) of about 0.5 s (50-300 keV). The time-averaged spectrum from T0-0.128 s to T0+0.576 s is well fit by a power law function with an exponential high-energy cutoff. The power law index is -0.65 +/- 0.16 and the cutoff energy, parameterized as Epeak, is 357.50 +/- 80.10 keV. The event fluence (10-1000 keV) in this time interval is (1.004 +/- 0.120)E-06 erg/cm^2. The 64-ms peak photon flux measured starting from T0 s in the 10-1000 keV band is 27 +/- 3 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/"
- Publication:
-
GRB Coordinates Network
- Pub Date:
- December 2021
- Bibcode:
- 2021GCN.31166....1H