TITLE:   GCN CIRCULAR
NUMBER:  44118
SUBJECT: GRB 260326A: Fermi GBM Detection
DATE:    26/03/26 11:21:12 GMT
FROM:    Utkarsh Pathak at IIT Bombay <utkarshpathak.07@gmail.com>

U. Pathak (IITB) and S. Bala (USRA) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:

"At 01:18:28.51 UT on 26 March 2026, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 260326A (trigger 796180713/260326054). 
The Fermi GBM real-time Localization is reported in GCN 44115.

The angle from the Fermi LAT boresight is 76 degrees.

The GBM light curve consists of two spikes from a single emission episode with a duration (T90)
of about 50 s (50-300 keV). The time-averaged spectrum
from T0-6.0 to T0+66.0 s is best fit by
a Band function with Epeak = 275 +/- 1 keV,
alpha = -1.040 +/- 0.004, and beta = -2.00 +/- 0.01.

The event fluence (10-1000 keV) in this time interval is
(5.37 +/- 0.05)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+7.0 s in the 10-1000 keV band is 32.6 +/- 0.4 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/"