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GCN Circular 36460

GRB 240511A: Fermi GBM Observation
2024-05-13T19:02:20Z (5 days ago)
Edited On
2024-05-13T19:17:54Z (5 days ago)
Lorenzo Scotton at UAH <>
Edited By
Leo P. Singer at NASA/GSFC <> on behalf of Lorenzo Scotton at UAH <>
Web form
L. Scotton (UAH) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:

"At 18:06:20.26 UT on 11 May 2024, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 240511A (trigger 737143585/240511754),
which was also detected by Swift BAT (S. Laha et al. 2024, GCN 36430).

The Fermi GBM Final Real-time Localization (GCN 36428) is consistent
with the Swift XRT position (P.A. Evans et al. 2024, GCN 36446).

The angle from the Fermi LAT boresight is 45.7 degrees.

The GBM light curve consists of a multi-peaked emission episode with a duration (T90)
of about 95 s (50-300 keV). The time-averaged spectrum
from T0-2.0 to T0+104.5 s is best fit by
a power law function with an exponential high-energy cutoff.
The power law index is -1.35 +/- 0.03 and the cutoff energy,
parameterized as Epeak, is 250 +/- 20 keV.

The event fluence (10-1000 keV) in this time interval is
(2.54 +/- 0.07)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+53 s in the 10-1000 keV band is 4.7 +/- 0.3 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:

For Fermi GBM data and info, please visit the official Fermi GBM Support Page:"
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