{
  "bibcode": "2015GCN.17942....1L",
  "body": "S. J. LaPorte (PSU) and A. Y. Lien (GSFC/UMBC) report on behalf of the\nSwift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 150616A\n579 s after the BAT trigger (Lien et al., GCN Circ. 17936).\nNo optical afterglow consistent with the XRT position\n(Evans et al. GCN Circ. 17937) 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           579          729          147         >21.0\nwhite              579         7913          616         >21.8\nv                  736         2624          214         >19.6\nb                  836         2878          365         >20.5\nu                  810         2700          214         >20.5\nw1                 786         2674          214         >20.2\nm2                 760         2649          136         >19.9\nw2                1016         2250          156         >20.1\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.04 in the direction of the burst\n(Schlegel et al. 1998).",
  "circularId": 17942,
  "createdOn": 1434569888000,
  "email": "siegel@swift.psu.edu",
  "subject": "GRB 150616A: Swift/UVOT Upper Limits",
  "submitter": "Mike Siegel at PSU/Swift MOC  <siegel@swift.psu.edu>",
  "eventId": "GRB 150616A"
}