TITLE:   GCN CIRCULAR
NUMBER:  35888
SUBJECT: GRB 240305A: Fermi GBM observation
DATE:    24/03/06 15:13:50 GMT
FROM:    Elisabetta Bissaldi at Politecnico and INFN Bari <elisabetta.bissaldi@ba.infn.it>

E. Bissaldi (Politecnico and INFN Bari) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 09:49:21.26 UT on 05 March 2024, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 240305A (trigger 731324966 / 240305409),
which was also detected by the Swift/BAT GUANO (DeLaunay et al. 2024, GCN 35880).
The Fermi GBM Final Real-time Localization (GCN 35869)
is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 56 degrees.

The GBM light curve consists of a single weak emission episode
with a duration (T90) of about 13 s (50-300 keV).
The time-averaged spectrum from T0-2.3 s to T0+10.2 s is
best fit by a simple power law function with index -2.06 +/- 0.07.

The event fluence (10-1000 keV) in this time interval is
(1.29 +/- 0.12)e-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+2.0 s in the 10-1000 keV band
is 2.05 +/- 0.19 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/"