{
  "bibcode": "2015GCN.17974....1E",
  "body": "P.A. Evans (U. Leicester), B.P. Gompertz (U. Leicester), A. Maselli \n(INAF-IASFPA), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), B.\nSbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU), T.G.R. Roegiers (PSU),\nJ.P. Osborne (U. Leicester) and L.M. McCauley report on behalf of the\nSwift-XRT team:\n\nWe have analysed 8.9 ks of XRT data for GRB 150626B (McCauley et al.\nGCN Circ. 17966), from 111 s to 23.5 ks after the  BAT trigger. The\ndata comprise 8 s in Windowed Timing (WT) mode (taken while Swift was\nslewing), with the remainder in Photon Counting (PC) mode. The enhanced\nXRT position for this burst was given by Goad et al. (GCN Circ. 17968).\nThe late-time light curve (from T0+5.3 ks) is consistent with a\nconstant source of mean count rate 1.9e-01 ct/sec. A power-law fit\ngives an index of 0.2 (+0.6, -0.5).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 1.99 (+/-0.15). The\nbest-fitting absorption column is  9.6 (+1.4, -1.3) x 10^21 cm^-2, in\nexcess of the Galactic value of 1.7 x 10^20 cm^-2 (Willingale et al.\n2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion\nfactor deduced from this spectrum  is 4.8 x 10^-11 (8.8 x 10^-11) erg\ncm^-2 count^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t     9.6 (+1.4, -1.3) x 10^21 cm^-2\nGalactic foreground: 1.7 x 10^20 cm^-2\nExcess significance: 11.7 sigma\nPhoton index:\t     1.99 (+/-0.15)\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/00646786.\n\nThis circular is an official product of the Swift-XRT team.",
  "circularId": 17974,
  "createdOn": 1435418200000,
  "email": "pae9@leicester.ac.uk",
  "subject": "GRB 150626B: Swift-XRT refined Analysis",
  "submitter": "Phil Evans at U of Leicester  <pae9@leicester.ac.uk>",
  "eventId": "GRB 150626B"
}