{
  "bibcode": "2009GCN..9822....1B",
  "body": "A. Breeveld (MSSL/UCL) and W. Baumgartner (GSFC) report on behalf of  \nthe Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 090817   \n11008 s after the INTEGRAL trigger (Beckmann et al., GCN Circ. 9815).  \nNo new sources are found in the UVOT data at the position of the XRT  \nsource (P.A. Evans et al., GCN Circ. 9819). Preliminary 3-sigma upper  \nlimits using the UVOT photometric system (Poole et al. 2008, MNRAS,  \n383, 627) and a 3 arcsec radius aperture, for the initial summed  \nexposures are:\n\nFilter         T_start(s)   T_stop(s)      Exp(s)         Mag\n\nwhite         11516        17719          413         >21.3\nv                11975        12398          416         >19.6\nb                11058        17509          787         >21.2\nu                11008        17157           78         >19.5\n\nThe values quoted above are not corrected for the Galactic extinction  \ndue to the reddening of E(B-V) = 0.66 in the direction of the burst  \n(Schlegel et al. 1998).",
  "circularId": 9822,
  "createdOn": 1250524708000,
  "email": "aab@mssl.ucl.ac.uk",
  "subject": "GRB 090817: Swift/UVOT Upper Limits",
  "submitter": "Alice Breeveld at MSSL-UCL  <aab@mssl.ucl.ac.uk>",
  "eventId": "GRB 090817"
}