{
  "bibcode": "2011GCN.12013....1V",
  "body": "A.J. van der Horst and A. Camero-Arranz (USRA) report on behalf of\nthe Fermi GBM Team:\n\n\"At 15:06:26.61 UT on 26 April 2011, the Fermi Gamma-Ray Burst Monitor\ntriggered on GRB 110426A (trigger 325523188 / 110426629). The on-ground\ncalculated location, using the GBM trigger data, is RA = 219.9, Dec = -8.7\n(J2000 degrees, equivalent to 14h40m, -8d43'), with an uncertainty of\n2.1 degrees (radius, 1-sigma containment, statistical only; there is\nadditionally a systematic error which is currently estimated to be 2\nto 3 degrees). The angle from the Fermi LAT boresight is 88 degrees.\n\nThis is most likely the same source as the one that MAXI/GSC reported\nin GCN 11980. Although MAXI/GSC triggered 130 seconds later than GBM on\nGRB 110426A, the locations obtained by both instruments are consistent.\nThe GBM light curve consists of multiple peaks with a duration (T90) of\n328 +/- 3 s (50-300 keV), indicating that the source was still active\nwhen MAXI/GSC detected it.\n\nThe time-averaged spectrum from T0-4.1 s to T0+327.7 s is adequately fit\nby a simple power law function with index -2.28 +/- 0.01. The event fluence\n(10-1000 keV) in this time interval is (4.54 +/- 0.06)E-5 erg/cm^2.\nThe 1-sec peak photon flux measured starting from T0+216.1 s in the\n10-1000 keV band is 6.7 +/- 0.4 ph/s/cm^2.\n\nWe note that there is bursting emission detected in GBM starting ~40\nminutes before the trigger. This emission is significantly softer than\nthe ~6 minute emission episode after the GBM trigger time. The start of\nthe spectrally soft bursts is consistent with Sco X-1 coming out of\nEarth occultation. The GRB 110426A location, however, is not consistent\nwith Sco X-1 and thus a separate source.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog.\"",
  "circularId": 12013,
  "createdOn": 1304984826000,
  "email": "Alexander.J.VanDerHorst@nasa.gov",
  "subject": "GRB 110426A: Fermi GBM detection",
  "submitter": "Alexander van der Horst at NASA/MSFC  <Alexander.J.VanDerHorst@nasa.gov>",
  "eventId": "GRB 110426A"
}