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GCN Circular 33407

GRB 230307A: Fermi GBM detection of a very bright GRB
2023-03-07T17:10:32Z (a year ago)
Sarah Dalessi at UAH <>
S. Dalessi(UAH)
report on behalf of the Fermi GBM Team:

"At 15:44:06.67 UT on 07 March 2023, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 230307A (trigger 699896651 / 230307656).

This event is one of the brightest among the GBM detected
GRBs. Follow-up across all wavelengths is encouraged.

The on-ground calculated location, using the GBM trigger
data, is RA = 54.06, DEC = -76.61 (J2000 degrees,
equivalent to J2000 03h 36m, -76d 35'), with a statistical uncertainty
of 1 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 142.0 degrees.

A full GCN of the Fermi-GBM analysis of this event will follow in a
later GCN, once the data has become available.

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