{
  "bibcode": "2017GCN.20560....1P",
  "body": "K.L. Page (U. Leicester), A. D'Ai (INAF-IASFPA), A. Melandri\n(INAF-OAB), P. D'Avanzo (INAF-OAB), J.A. Kennea (PSU), B. Sbarufatti\n(INAF-OAB/PSU), D.N. Burrows (PSU), B. Mingo (U. Leicester), A.P.\nBeardmore (U. Leicester) and  report on behalf of the Swift-XRT team:\nreport on behalf of the Swift-XRT team:\n\nWe have analysed 2.8 ks of XRT data for GRB 170127B, from 60 s to 10.6\nks after the  BAT trigger. The data comprise 7 s in Windowed Timing\n(WT) mode (taken while Swift was slewing), with the remainder in Photon\nCounting (PC) mode. \n\nThe light curve can be modelled with a power-law decay with a decay\nindex of alpha=1.7 (+0.5, -0.4).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 1.57 (+0.27, -0.23). The\nbest-fitting absorption column is  consistent with the Galactic value\nof 2.0 x 10^20 cm^-2 (Willingale et al. 2013). The counts to observed\n(unabsorbed) 0.3-10 keV flux conversion factor deduced from this\nspectrum  is 4.1 x 10^-11 (4.2 x 10^-11) erg cm^-2 count^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t     2.0 (+/-4.2) x 10^20 cm^-2\nGalactic foreground: 2.0 x 10^20 cm^-2\nExcess significance: <1.6 sigma\nPhoton index:\t     1.57 (+0.27, -0.23)\n\nIf the light curve continues to decay with a power-law decay index of\n1.7, the count rate at T+24 hours will be 6.7 x 10^-6 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.7 x\n10^-16 (2.8 x 10^-16) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/00735331.\n\nThis circular is an official product of the Swift-XRT team.",
  "circularId": 20560,
  "createdOn": 1485617105000,
  "email": "pae9@leicester.ac.uk",
  "subject": "GRB 170127B: Swift-XRT refined Analysis",
  "submitter": "Phil Evans at U of Leicester  <pae9@leicester.ac.uk>",
  "eventId": "GRB 170127B"
}