{
  "bibcode": "2015GCN.17965....1M",
  "body": "V. Mangano (PSU), C. Pagani (U. Leicester), A.P. Beardmore (U.\nLeicester), P.A. Evans (U. Leicester), V. D'Elia (ASDC), A. D'ai\n(INAF-IASFPA), A. Maselli  (INAF-IASFPA), M.C. Stroh (PSU), D.N.\nBurrows (PSU) and T.G.R. Roegiers report on behalf of the Swift-XRT\nteam:\n\nWe have analysed 9.2 ks of XRT data for GRB 150626A (Roegiers et al.\nGCN Circ. 17960), from 77 s to 31.2 ks after the  BAT trigger. The data\ncomprise 206 s in Windowed Timing (WT) mode (the first 9 s were taken\nwhile Swift was slewing) with the remainder in Photon Counting (PC)\nmode. The enhanced XRT position for this burst was given by Evans et\nal. (GCN Circ. 17961).\n\nThe late-time light curve (from T0+6.3 ks) can be modelled with a\npower-law decay with a decay index of alpha=0.65 (+/-0.17).\n\nA spectrum formed from the WT mode data can be fitted with an absorbed\npower-law with a photon spectral index\tof 2.08 (+/-0.06). The\nbest-fitting absorption column is  3.74 (+0.31, -0.24) x 10^21 cm^-2,\nconsistent with the Galactic value of 3.5 x 10^21 cm^-2 (Willingale et\nal. 2013). The PC mode spectrum has a photon index of 2.06 (+0.19,\n-0.18) and a best-fitting absorption column of 4.5 (+1.0, -0.9) x 10^21\ncm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion\nfactor deduced from this spectrum  is 3.9 x 10^-11 (6.4 x 10^-11) erg\ncm^-2 count^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t     4.5 (+1.0, -0.9) x 10^21 cm^-2\nGalactic foreground: 3.5 x 10^21 cm^-2\nExcess significance: 1.8 sigma\nPhoton index:\t     2.06 (+0.19, -0.18)\n\nIf the light curve continues to decay with a power-law decay index of\n0.65, the count rate at T+24 hours will be 0.018 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 6.8 x\n10^-13 (1.1 x 10^-12) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/00646603.\n\nThis circular is an official product of the Swift-XRT team.",
  "circularId": 17965,
  "createdOn": 1435329153000,
  "email": "pae9@leicester.ac.uk",
  "subject": "GRB 150626A: Swift-XRT refined Analysis",
  "submitter": "Phil Evans at U of Leicester  <pae9@leicester.ac.uk>",
  "eventId": "GRB 150626A"
}