GCN Circular 36499

S. Bala (USRA), S. Dalessi (UAH) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:

"At 03:36:24.84 UT on 16 May 2024, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 240516A (trigger 737523389/240516150).
which was also detected by Swift BAT (T. M. Parsotan et al. 2024, GCN 36493
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 ).
The Fermi GBM on-ground location is consistent with the Swift BAT position.

The angle from the Fermi LAT boresight is 47 degrees.

The GBM light curve consists of a single emission episode with a duration (T90)
of about 46 s (50-300 keV). The time-averaged spectrum
from T0+1.0 to T0+45.1 s is best fit by
a power law function with an exponential high-energy cutoff.
The power law index is -0.69 +/- 0.09 and the cutoff energy,
parameterized as Epeak, is 528 +/- 72 keV.

The event fluence (10-1000 keV) in this time interval is
(1.12 +/- 0.06)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+3.7 s in the 10-1000 keV band is 2.4 +/- 0.2 ph/s/cm^2.

A Band function fits the spectrum equally well
with Epeak= 490 +/- 107 keV, alpha = -0.7 +/- 0.1 and beta = -2.1 +/- 0.3.

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/"