TITLE:   GCN CIRCULAR
NUMBER:  25975
SUBJECT: Fermi/GBM observation of a bright burst from magnetar SGR 1935+2154
DATE:    19/10/07 18:37:12 GMT
FROM:    Joshua Wood at MSFC/Fermi-GBM  <joshua.r.wood@nasa.gov>

J.Wood (NASA/MSFC) and E. Bissaldi (Politecnico & INFN Bari)
report on behalf of the Fermi GBM Team:

"At 09:00:53.70 UT on 4 October 2019, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered on a bright, SGR-like burst from the direction of
the magnetar SGR 1935+2154 (trigger 591872458/191004376).

The burst has a duration (T90) of ~0.1 seconds in the energy range 10-300 keV.
It is well-fit by a Comptonized model with Epeak 28.71 +/- 2.71 keV and alpha -0.30 +/- 0.55.

The event fluence (10-300 keV) from T0-0.112s to T0+0.016s is (7.142 +/- 0.576)E-8 erg/cm^2.
The average photon flux in the 10-300 keV band during this period is 14.19 +/- 1.0 ph/s/cm^2.

We note that this is the first outburst since June 2016.
The analysis results presented above are preliminary.

For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"