{
  "bibcode": "2008GCN..8405....1S",
  "body": "G. Stratta (ASDC) reports on behalf of the Swift-XRT team:\n\nWe have analysed the first orbit of the XRT data obtained for\nGRB 081024 (Stratta et al., GCN Circ. 8398). From T+78 s to T+105 s\nafter the burst, data were collected in Windowed Timing mode and\nthen XRT switched to Photon Counting mode. The Enhanced Swift-XRT\nposition was given by Beardmore et al. in GCN Circ. 8403.\n\nThe 0.3-10 keV flux from T+78 s to T+355 s shows a very steep decay with\na possible small re-brightening between ~T+145 s to ~T+205 s. Excluding\nthe re-brightening and assuming a power law decay, the best fit decay\nindex is alpha = 3.7 (+0.8,-0.5).\n\nThe spectrum of the WT data, with an integration time of 27s, can\nbe modelled with a power-law model with photon index of 1.6 (+0.6,- 0.3).\nThe total absorbing equivalent hydrogen column density is consistent\nwith the Galactic one NH = 7.71E+21 cm^-2 (Kalberla et al. 2005). The\nobserved (unabsorbed) 0.3-10 keV flux is 4.1(6.1)E-10 erg/cm^-2 s^-1\n\nNo source counts are detected after the first orbit, likely due to\nthe very steep flux decay.\n\nThis is an official product of the Swift-XRT team.",
  "circularId": 8405,
  "createdOn": 1224880268000,
  "email": "perri@asdc.asi.it",
  "subject": "GRB 081024: Swift-XRT refined analysis",
  "submitter": "Matteo Perri at ISAC/ASDC  <perri@asdc.asi.it>",
  "eventId": "GRB 081024"
}