{
  "bibcode": "2013GCN.15275....1M",
  "body": "F. E. Marshall (NASA/GSFC) reports on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 130929A\n280 s after the BAT trigger (Marshall et al., GCN Circ. 15269).\nNo optical afterglow consistent with the XRT position\n(Goad et al. GCN Circ. 15271) is detected in the initial UVOT exposures.\nPreliminary 3-sigma upper limits using the UVOT photometric system\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first\nfinding chart (FC) exposure and subsequent exposures are:\n\nFilter         T_start(s)   T_stop(s)      Exp(s)         Mag\n\nwhite_FC           280          430          147         >21.0\nwhite              280         1008          334         >21.4\nv                  586         4628          236         >19.7\nb                  512          705           39         >19.0\nu                  487        10592          709         >20.6\nw1                 462         6710          255         >19.6\nm2                 437         6505          308         >19.7\nw2                 562         4423          236         >19.7\n\nThe magnitudes in the table are not corrected for the \nlarge Galactic extinction in the direction of the burst\n(Schlegel et al. 1998).",
  "circularId": 15275,
  "createdOn": 1380564427000,
  "email": "femarsha@khamseen.gsfc.nasa.gov",
  "subject": "GRB 130929A: Swift/UVOT Upper Limits",
  "submitter": "Frank Marshall at GSFC  <femarsha@khamseen.gsfc.nasa.gov>",
  "eventId": "GRB 130929A"
}