{
  "bibcode": "2009GCN..8891....1P",
  "body": "M. Perri and G. Stratta (ASDC) report on behalf of the Swift XRT team:\n\nWe have analyzed the first 13.5 ks of Swift-XRT data of the BAT GRB\n090205 (Perri et al., GCN Circ. 8884). The data, starting at 2009-02-05\n23:04:55 UT and ending at 2009-02-06 09:10:33 UT, is all taken in\nPhoton Counting (PC) mode.\n\nThe best XRT position is the UVOT-enhanced position reported by\nEvans et al. (GCN Circ. 8885).\n\nIn the time interval T+94s-T+580 s the X-ray light curve can be modeled by\na simple power law with a decay index alpha_1= 1.4 � 0.3 (90% confidence)\nfollowed by a re-brightening around T+1 ks. After the re-brightnening,\nfrom T+5 ks up to T+30 ks, the light curve decays with a power law\nindex alpha_2= 0.9 � 0.2.\n\nThe X-ray spectrum is well fit by an absorbed power-law model\nwith a photon index of 2.0 (+/-0.2) and a column density consistent\nwith the Galactic one in the direction of the source (7.7e20 cm**-2,\nKalberla et al. 2005). The estimated 3-sigma (2-sigma) upper limit on the\nintrinsic column density at z=4.6 (Thoene et al., GCN Circ. 8889) is\n4.1e22cm**-2 (2.8e22cm**-2).\n\nAssuming the X-ray emission continues to decline at the same rate, we\npredict a 0.3-10 keV XRT count rate of 6e-3 count/s at T+24hr, which\ncorresponds to an observed 0.3-10 keV flux of ~2e-13 erg/cm**2/s.\n\nThis circular is an official product of the Swift-XRT Team.",
  "circularId": 8891,
  "createdOn": 1233935930000,
  "email": "perri@asdc.asi.it",
  "subject": "GRB 090205: Swift-XRT refined analysis",
  "submitter": "Matteo Perri at ISAC/ASDC  <perri@asdc.asi.it>",
  "eventId": "GRB 090205"
}