{
  "bibcode": "2009GCN..8921....1G",
  "body": "S. Guiriec (UAH)\nreports on behalf of the Fermi GBM Team:\n\n\"At 18:31:01.41 UT on 27 February 2009, the Fermi Gamma-Ray Burst Monitor\ntriggered and located the short and bright GRB 090227B\n(trigger 257452263 / 090227772).\n\nThe on-ground calculated location, using the GBM trigger data, is\nRA = 11.81, Dec = +32.17 (J2000 degrees, equivalent to 11h48m36,+32d10'12),\nwith an uncertainty of 1.77 degrees (radius, 1-sigma containment,\nstatistical only; there is additionally a systematic error which is\ncurrently estimated to be 2 to 3 degrees).\n\nThe angle from the Fermi LAT boresight is 72 degrees.\n\nThis burst was also independently detected by INTEGRAL SPI-ACS.\n\nThe GBM light curve consists of one spike with a duration (T90) of about\n0.9 s (10-1000 keV).\nThe time-averaged spectrum from T0-0.1s to T0+0.4s is best fitted by a Band\nfunction with Epeak = 2255 +/- 116 keV,  alpha = -0.53 +/- 0.02, and\nbeta = -3.04 +/- 0.23 (chi squared 673 for 607 d.o.f.).\n\nThe event fluence (10-1000 keV) in this time interval is\n(0.87 +/- 0.01)E-05 erg/cm^2. The 1-sec peak photon flux measured starting\nfrom T0 in the 10-1000 keV band is 34.6 +/- 0.3 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog.\"",
  "circularId": 8921,
  "createdOn": 1235897358000,
  "email": "sylvain.guiriec@lpta.in2p3.fr",
  "subject": "GRB 090227B: Fermi GBM detection",
  "submitter": "Sylvain Guiriec at UAH  <sylvain.guiriec@lpta.in2p3.fr>",
  "eventId": "GRB 090227B"
}