{
  "circularId": 33926,
  "createdOn": 1686057529370,
  "subject": "GRB 230606A: Swift/UVOT Upper Limits",
  "submitter": "Alice Breeveld at MSSL-UCL <a.breeveld@ucl.ac.uk>",
  "eventId": "GRB 230606A",
  "body": "A. A. Breeveld (UCL-MSSL) and A. Y. Lien (U. Tampa) report on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 230606A 2784 s after the BAT trigger (Lien et al., GCN Circ. 33921).\nNo optical afterglow consistent with the XRT position (Goad et al., GCN Circ. 33924) is detected in the initial UVOT exposures.\nPreliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are:\n\nFilter         T_start(s)   T_stop(s)      Exp(s)         Mag\n\nwhite_FC          2784         2934          147         >20.3\nwhite             2784         3554          344         >21.1\nv                 3765         3965          197         >19.2\nb                 3149         3349          197         >20.2\nu                 2943         4514          328         >20.1\nw1                4176         4376          197         >20.2\nw2                3560         3760          197         >20.3\n\nThe magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.015 in the direction of the burst (Schlegel et al. 1998).\n",
  "bibcode": "2023GCN.33926....1B"
}