{
  "bibcode": "2010GCN.11072....1S",
  "body": "C. A. Swenson and D. Grupe (PSU) report on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 100807A\n91 s after the BAT trigger (Grupe et al., GCN Circ. 11067).  No optical\nafterglow consistent with the enhanced XRT position (Osborne et al.,\nGCN Circ. 11070) is detected in the initial UVOT exposures.  Preliminary\n3-sigma upper limits using the UVOT photometric system (Poole et al. 2008,\nMNRAS, 383, 627) for the first finding chart (FC) exposure and subsequent\nexposures are:\n\nFilter         T_start(s)   T_stop(s)      Exp(s)         Mag\n\nwhite_FC            91          240          147         >20.9\nu_FC               304          553          246         >20.4\nwhite               91         5947          530         >21.8\nv                  634         6358          255         >19.6\nb                  559         7063          319         >21.1\nu                  304         6973          659         >21.1\nw1                 683         6768          413         >20.8\nm2                6363         6563          197         >20.7\nw2                 609         6153          255         >20.8\n\nThe values quoted above are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.81 in the direction of the burst\n(Schlegel et al. 1998).",
  "circularId": 11072,
  "createdOn": 1281196656000,
  "email": "cswenson@astro.psu.edu",
  "subject": "GRB 100807A:  Swift/UVOT Upper Limits",
  "submitter": "Craig Swenson at PSU/Swift  <cswenson@astro.psu.edu>",
  "eventId": "GRB 100807A"
}