{
  "bibcode": "2009GCN..9550....1B",
  "body": "A.P. Beardmore, K.L. Page (U. Leicester) and P.A. Curran (UCL-MSSL)\nreport on behalf of the Swift-XRT team:\n\nWe have analysed five orbits of Swift-XRT photon counting (PC) mode data \nfrom GRB 090621B (Curran et al., GCN Circ. 9545), spanning the interval \nT+80 s to T+19.5 ks after the trigger.  In 10.0 ks we find a refined XRT \nposition of RA, Dec = 313.47049, 69.02845, which is equivalent to\n\nRA (J2000) =  20:53:52.92\nDec(J2000) = +69:01:42.4\n\nwith an uncertainty of 4.0 arcsec (90% containment). This position\nis 1.2 arcsec from the XRT position quoted in GCN Circ. 9545.\n\nThe X-ray light-curve shows a faint, fading source with a decay index\nof 0.61  +/- 0.19. If the source continues to decay at the same rate \nwe predict an XRT count rate of 8.6e-4 count s^-1 at T+24 hours.\n\nThe PC mode spectrum from T+80 s to T+17.1 ks can be fit by an absorbed \npowerlaw with a photon index of 1.47+/-0.66, assuming a Galactic column \ndensity of 1.9e21cm^-2 in the direction of the burst.  The observed \n(unabsorbed) 0.3-10keV flux for this model is 3.8e-13 (4.5e-13)\nerg cm^-2 s^-1.\n\nThis circular is an official product of the Swift-XRT team.",
  "circularId": 9550,
  "createdOn": 1245665815000,
  "email": "apb@star.le.ac.uk",
  "subject": "GRB 090621B: Swift-XRT refined analysis",
  "submitter": "Andy Beardmore at U Leicester  <apb@star.le.ac.uk>",
  "eventId": "GRB 090621B"
}