{
  "bibcode": "2009GCN..8918....1V",
  "body": "A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team: \n\n\"At 04:53:20.91 UT on 28 February 2009, the Fermi Gamma-Ray Burst Monitor\ntriggered and located the bright short GRB 090228 (trigger 257489602 /\n090228204).\nThe on-ground calculated location, using the GBM trigger \ndata, is RA = 106.8, DEC = -24.3 (J2000 degrees, equivalent \nto 07h 07m, -24d 18'), with a statistical uncertainty of \nless than 1 degree (radius, 1-sigma containment) and an additional \nsystematic error which is currently estimated to be 2 to 3 degrees.\n\nThe angle from the Fermi LAT boresight is 16 degrees\n\nThis short GRB shows a single bright pulse followed \nby a peak of significantly lesser intensity. \nThe burst duration (T90) is about 0.8 s (8-1000 keV).\nThe time-averaged spectrum from T0-0.016 s to T0+0.176 s is \nbest fit by a Band function with Epeak = 849 +/- 44 keV, \nalpha = -0.35 +/- 0.04, and beta = -2.98 +/- 0.25\n(chi squared 732.29 for 723 d.o.f.).\n\nThe event fluence (8-1000 keV) in this time interval is \n(6.1 +/- 0.09)E-06 erg/cm^2. The 0.32-sec peak photon flux measured \nstarting from T0 s in the 8-1000 keV band is 133 +/- 8 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary; \nfinal results will be published in the GBM GRB Catalog.\"",
  "circularId": 8918,
  "createdOn": 1235842935000,
  "email": "azk@mpe.mpg.de",
  "subject": "GRB 090228: Fermi GBM detection",
  "submitter": "Andreas von Kienlin at MPE  <azk@mpe.mpg.de>",
  "eventId": "GRB 090228"
}