{
  "bibcode": "2021GCN.30806....1R",
  "body": "O.J. Roberts (USRA/NASA-MSFC), J. Wood (USRA/NASA-MSFC),\nreport on behalf of the Fermi GBM Team:\n\n\"At 00:45:46.94 UT on 10 September 2021, the Fermi Gamma-Ray Burst Monitor (GBM)\ntriggered and located a bright, SGR-like flare from the direction of\nthe magnetar SGR 1935+2154 (trigger 652927551/210910032).\n\nThe flare was also observed by Konus Wind (Ridnaia et al., GCN 30804) and\ntriangulated to an annulus incorporating the SGR position by the IPN (Ridnaia et al., GCN 30803).\nThe on-ground calculated location using the Fermi GBM trigger data, is consistent\nwith the known position of the SGR and the IPN localization.\n\nThe angle from the Fermi LAT boresight at the GBM trigger time is 102 degrees.\n\nThe burst has a duration (T90) of about 1.4 s (10-1000 keV).\n\nIt is best fit by a double-blackbody model with temperatures of\nkT1 = 8.51 +/- 0.08 keV and kT2 = 16.55 +/- 0.18 keV.\n\nThe event fluence (10-1000 keV) from T0-0.064s to T0+1.328s is\n(3.858 +/- 0.011)E-05 erg/cm^2. The average photon flux in the\n10-1000 keV band during this period is 522.7 +/- 1.5 ph/s/cm^2.\n\nFermi GBM has also triggered on 14 other bursts from the direction of SGR 1935+2154 over\nthe last 4 days, indicating it has entered a stage of heightened activity in this latest outburst:\n\nDate and Time in UTC     Fermi MET (s)\n2021-09-06T01:44:30.10  652585475\n2021-09-09T18:57:14.86  652906639\n2021-09-09T20:21:28.37  652911693\n2021-09-10T00:45:46.94  652927551\n2021-09-10T01:00:43.71  652928448\n2021-09-10T01:13:17.40  652929202\n2021-09-10T01:27:05.60  652930030\n2021-09-10T02:21:06.44  652933271\n2021-09-10T02:36:38.24  652934203\n2021-09-10T02:55:10.17  652935315\n2021-09-10T05:35:55.51  652944960\n2021-09-10T09:12:48.91  652957973\n2021-09-10T15:50:56.89  652981861\n2021-09-10T23:40:34.46  653010039\n\nThe spectral analysis results presented above are preliminary. We encourage multi-wavelength\nobservations to follow-up this most recent activation. For Fermi GBM data and info, please visit the\n official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"",
  "circularId": 30806,
  "createdOn": 1631319644000,
  "email": "oliver.roberts@nasa.gov",
  "subject": "Fermi GBM observation of a bright flare in the direction of SGR 1935+2154",
  "submitter": "Oliver J Roberts at USRA/NASA  <oliver.roberts@nasa.gov>",
  "eventId": "SGR 1935+2154"
}