{
  "bibcode": "2016GCN.19868....1E",
  "body": "P.A. Evans (U. Leicester), A. D'Ai (INAF-IASFPA), A. Maselli \n(INAF-IASFPA), A. Melandri (INAF-OAB), J.A. Kennea (PSU), B. Sbarufatti\n(INAF-OAB/PSU), D.N. Burrows (PSU), S.L. Gibson (U. Leicester), J.P.\nOsborne (U. Leicester) and B. Mingo report on behalf of the Swift-XRT\nteam:\n\nWe have analysed 6.5 ks of XRT data for GRB 160826A (Mingo et al. GCN\nCirc. 19866), from 93 s to 22.1 ks after the  BAT trigger. The data\ncomprise 114 s in Windowed Timing (WT) mode (the first 5 s were taken\nwhile Swift was slewing) with the remainder in Photon Counting (PC)\nmode. The refined XRT position is RA, Dec = 183.1127, -67.6639 which is\nequivalent to:\n\nRA (J2000): 12 12 27.05\nDec(J2000): -67 39 50.0\n\nwith an uncertainty of 3.5 arcsec (radius, 90% confidence).\n\nThe light curve can be modelled with a power-law decay with a decay\nindex of alpha=1.64 (+0.06, -0.05).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 1.68 (+0.31, -0.28). The\nbest-fitting absorption column is  9.1 (+3.3, -2.7) x 10^21 cm^-2, in\nexcess of the Galactic value of 4.6 x 10^21 cm^-2 (Willingale et al.\n2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion\nfactor deduced from this spectrum  is 5.7 x 10^-11 (8.5 x 10^-11) erg\ncm^-2 count^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t     9.1 (+3.3, -2.7) x 10^21 cm^-2\nGalactic foreground: 4.6 x 10^21 cm^-2\nExcess significance: 2.7 sigma\nPhoton index:\t     1.68 (+0.31, -0.28)\n\nIf the light curve continues to decay with a power-law decay index of\n1.64, the count rate at T+24 hours will be 2.1 x 10^-4 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.2 x\n10^-14 (1.7 x 10^-14) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/00709907.\n\nThis circular is an official product of the Swift-XRT team.",
  "circularId": 19868,
  "createdOn": 1472225780000,
  "email": "pae9@leicester.ac.uk",
  "subject": "GRB 160826A: Swift-XRT refined Analysis",
  "submitter": "Phil Evans at U of Leicester  <pae9@leicester.ac.uk>",
  "eventId": "GRB 160826A"
}