{
  "bibcode": "2006GCN..5577....1G",
  "body": "C. Guidorzi, P. Romano, A. Moretti, S. Vergani on behalf of the\nSwift XRT team report:\n\n\nwe have analysed the first orbit of XRT data from GRB 060919\n(Guidorzi et al., GCN Circ 5575). A 1.3 ks Photon Counting mode image\nprovides a refined XRT position:\n\nRA(J2000)  =  18h 27m 42.21s,\nDec(J2000) = -51d 00m 50.4s\n\nwith an uncertainty of 4.1 arcsec (90% containment). This position is 1.6\narcsec away from the previous XRT position and 56 arcsec from the onboard\nBAT position (Guidorzi et al., GCN Circ 5575).\n\nThe X-ray light curve can be fit with a single power law with index\n0.85 +- 0.2 (90%) from 100 to 1400 seconds after the BAT trigger.\n\nA power-law fit to the 0.3-10 keV spectrum yields a photon index\nof 1.7+-0.5 and a column density of (9+-4)x1e21 cm-2 (90%),\nsignificantly in excess of the Galactic hydrogen column density\nin the direction of the burst (6.4e20cm-2).\n\nThe average unabsorbed flux of the first orbit is (1.1+-0.3)e-11 erg \ncm-2 s-1.\nIf the burst decays at the current rate we estimate a\n0.3-10 keV unabsorbed flux of ~1.2e-13 ergs cm-2 s-1 at T+24hr.\n\nThis circular is an official product of the Swift XRT Team.",
  "circularId": 5577,
  "createdOn": 1158677147000,
  "email": "cristiano.guidorzi@brera.inaf.it",
  "subject": "GRB060919: XRT refined analysis",
  "submitter": "Cristiano Guidorzi at INAF-OAB  <cristiano.guidorzi@brera.inaf.it>",
  "eventId": "GRB 060919"
}