{
  "bibcode": "2021GCN.30831....1R",
  "body": "O.J. Roberts (USRA/NASA-MSFC) reports on behalf of the Fermi GBM Team:\n\n\"At 20:16:10.44 UT on 12 September 2021, the Fermi Gamma-Ray Burst Monitor (GBM)\ntriggered and located a bright, SGR-like burst from the direction of\nthe magnetar SGR 1935+2154 (trigger 653170575/210912845).\n\nThe GBM on-ground location is consistent with the known position of the SGR.\n\nThe angle from the Fermi LAT boresight at the GBM trigger time is 96 degrees.\n\nThe event episode has a duration (T90) of about 1 s (10-1000 keV). During this\ntime interval, there are several very short bursts. The first burst has a\nrapid risetime.\n\nThe whole event is best fit with a power law function\nwith an exponential high-energy cutoff. The power law index is 0.08 +/- 0.08 and\nthe cutoff energy, parameterized as Epeak, is 32.1 +/- 0.3 keV.\n\nThe time-integrated event fluence (10-1000 keV) from T0-0.064 to T0+0.944s is\n(3.545 +/- 0.038)E-6 erg/cm^2. The average photon flux in the\n10-1000 keV band during this period is 84 +/- 1 ph/s/cm^2.\n\nFermi GBM has also triggered on a further 24 bursts from the direction of SGR 1935+2154\nsince yesterday's GCN (Roberts and Wood, GCN 30806):\n\nDate and Time in UTC     Fermi MET (s)\n2021-09-12T23:19:32.08  653181577\n2021-09-12T20:16:10.44  653170575\n2021-09-12T15:03:50.60  653151835\n2021-09-12T13:55:16.45  653147721\n2021-09-12T12:19:20.44  653141965\n2021-09-12T10:10:11.73  653134216\n2021-09-12T07:28:07.46  653124492\n2021-09-12T06:51:13.22  653122278\n2021-09-12T05:14:07.84  653116452\n2021-09-11T02:36:38.24  653093506\n2021-09-11T20:22:59.04  653084584\n2021-09-11T20:05:46.22  653083551\n2021-09-11T18:54:36.05  653079281\n2021-09-11T17:01:09.77  653072474\n2021-09-11T16:50:03.83  653071808\n2021-09-11T16:36:57.91  653071022\n2021-09-11T15:26:11.55  653066776\n2021-09-11T15:15:25.44  653066130\n2021-09-11T15:03:00.55  653065385\n2021-09-11T13:27:33.85  653059658\n2021-09-11T11:53:57.29  653054042\n2021-09-11T10:42:51.85  653049776\n2021-09-11T05:32:38.65  653031163\n2021-09-11T03:02:28.36  653022153\n\nFermi GBM will not report on future triggers from this event.\n\nThe spectral analysis results presented above are preliminary. We encourage multi-wavelength\nobservations to follow-up this most recent activation.\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"",
  "circularId": 30831,
  "createdOn": 1631503994000,
  "email": "oliver.roberts@nasa.gov",
  "subject": "Fermi GBM observation of another bright burst in the direction of SGR 1935+2154",
  "submitter": "Oliver J Roberts at USRA/NASA  <oliver.roberts@nasa.gov>",
  "eventId": "SGR 1935+2154"
}