{
  "bibcode": "2013GCN.14788....1M",
  "body": "A. Melandri (INAF/OAB) and S. T. Holland (STScI) report on behalf of\nthe Swift-XRT team:\n\nWe have analysed 15 ks of XRT data for GRB 130605A (Holland  et al. GCN\nCirc. 14773),  from 78 s to 58.5 ks after the  BAT trigger. The data\ncomprise 385 s in Windowed Timing (WT) mode (the first 8 s were taken\nwhile Swift was slewing) with the remainder in Photon Counting (PC)\nmode. Using 6133 s of PC mode data and 5 UVOT images, we find an\nenhanced XRT position (using the XRT-UVOT alignment and matching UVOT\nfield sources to the USNO-B1 catalogue): RA, Dec = 134.53571, -33.46152\nwhich is equivalent to:\n\nRA (J2000): 08h 58m 08.57s\nDec(J2000): -33d 27' 41.5\"\n\nwith an uncertainty of 1.8 arcsec (radius, 90% confidence).\n\nThe light curve can be modelled with  a power-law decay with a decay\nindex of alpha=1.23 (+/-0.05).\n\nA spectrum formed from the WT mode data can be fitted with an absorbed\npower-law with a photon spectral index\tof 2.3 (+0.5, -0.3). The\nbest-fitting absorption column is  2.35 (+1.96, -0.16) x 10^21 cm^-2,\nconsistent with the Galactic value of 2.2 x 10^21 cm^-2 (Kalberla et\nal. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux\nconversion factor deduced from this spectrum  is 2.7 x 10^-11 (5.0 x\n10^-11) erg cm^-2 count^-1. \n\nA summary of the WT-mode spectrum is thus:\nTotal column:\t     2.35 (+1.96, -0.16) x 10^21 cm^-2\nGalactic foreground: 2.2 x 10^21 cm^-2\nExcess significance: <1.6 sigma\nPhoton index:\t     2.3 (+0.5, -0.3)\n\nIf the light curve continues to decay with a power-law decay index of\n1.23, the count rate at T+24 hours will be 9.4 x 10^-4 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.6 x\n10^-14 (4.7 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/00557508.\n\nThis circular is an official product of the Swift-XRT team.",
  "circularId": 14788,
  "createdOn": 1370561766000,
  "email": "andrea.melandri@brera.inaf.it",
  "subject": "GRB 130605A: Swift-XRT refined Analysis",
  "submitter": "Andrea Melandri at INAF-OAB  <andrea.melandri@brera.inaf.it>",
  "eventId": "GRB 130605A"
}