TITLE: GCN CIRCULAR NUMBER: 24013 SUBJECT: GRB 190326B: Fermi GBM detection DATE: 19/03/26 13:54:58 GMT FROM: Andreas von Kienlin at MPE A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team: "At 07:31:39.00 UT on 26 March 2019, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 190326B (trigger 575278303 / 190326314). The on-ground calculated location, using the GBM trigger data, is RA = 264.2, DEC = 68.3 (J2000 degrees, equivalent to 17h 37m, 68d 18'), with an uncertainty of 1.3 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 21 degrees. The GBM light curve consists of multiple pulses with a duration (T90) of about 56 s (50-300 keV). The time-averaged spectrum from T0-2.048 s to T0+59.393 s is best fit by a Band function with Epeak = 163 +/- 14 keV, alpha = -0.33 +/- 0.10, and beta = -1.93 +/- 0.07 The event fluence (10-1000 keV) in this time interval is (1.78 +/- 0.05)E-05 erg/cm^2. The 1.024-sec peak photon flux measured starting from T0+56.5128 s in the 10-1000 keV band is 7.8 +/- 0.3 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."