{
  "bibcode": "2010GCN.10352....1M",
  "body": "R. Margutti, B. Sbarufatti (INAF-OAB), S. Oates (MSSL/UCL),\nreport on behalf of the Swift-XRT team:\n\nThe Swift ToO observations of the BATSS burst GRB 100115A\n(Cummings et al., GCN Circ. 10325) started  40ks  after the\ntrigger. The XRT data set consists of 8 ks exposure in PC mode\nsplit into two epochs: the first observation was performed\nat T0+40 ks, while a second epoch of observations was acquired\nat T0+306 ks. The UVOT-enhanced XRT position was given by\nMargutti et al. in GCN Circ. 10334.\n\nIn the second observation the X-ray source reported by Margutti\net al., GCN Circ.10326 has faded to a level of (1.4 +/- 0.9)e-3\ncount/sec corresponding to a decay index of -0.7 +/- 0.4.\nThis source is likely to be the afterglow of GRB 100115A.\nNo further observations are planned.\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 2.0 (+1.0, -0.5). The\nbest-fitting absorption column is consistent with the Galactic value\nof 3.1 x 10^20 cm^-2 (Kalberla et al. 2005). The counts to observed\n(unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum\nis 3.4 x 10^-11 (3.8 x 10^-11) erg cm^-2 count^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/00020126.\n\nThis circular is an official product of the Swift-XRT team.",
  "circularId": 10352,
  "createdOn": 1263977701000,
  "email": "raffaella.margutti@brera.inaf.it",
  "subject": "GRB 100115A: Swift-XRT refined analysis",
  "submitter": "Raffaella Margutti at U. di Milano Bicocca  <raffaella.margutti@brera.inaf.it>",
  "eventId": "GRB 100115A"
}