TITLE: GCN CIRCULAR NUMBER: 33545 SUBJECT: GRB 230330B: Fermi GBM Final Localization DATE: 23/03/30 16:48:56 GMT FROM: Joshua Wood at MSFC/Fermi-GBM joshua.r.wood@nasa.gov

The Fermi GBM team reports the detection of a likely LONG GRB

"At 00:26:04 UT on 30 March 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230330B (trigger 701828769/230330018).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 65.05, Dec = -35.22 (J2000 degrees, equivalent to J2000 4h 20m, -35d 13'), with a statistical uncertainty of 8.61 degrees.

The angle from the Fermi LAT boresight is 32 degrees.

The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230330018/q...

The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230330018/q...

The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230330018/q..."