{
  "submitter": "Alice Breeveld at MSSL-UCL <a.breeveld@ucl.ac.uk>",
  "body": "A. A. Breeveld (UCL-MSSL) and R. A. J. Eyles-Ferris (U Leicester) report on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 230826A 114 s after the BAT trigger (Eyles-Ferris et al., GCN Circ. 34565).\nNo optical afterglow consistent with the enhanced XRT position (Osborne et al., GCN Circ. 34569) 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           114          263        147           >20.0\nwhite              606         5452        312           >20.4\nv                  657         1105         58           >17.8\nb                  582         5339        255           >19.6\nu                  327         5134        481           >19.5\nuvw1               707         1320         71           >18.4\nuvm2               682         1303         78           >18.4\nuvw2               632         1254         78           >18.6\n\nThe magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.243 in the direction of the burst (Schlegel et al. 1998).\n",
  "createdOn": 1693218102237,
  "subject": "Subject: GRB230826A: Swift/UVOT upper limits",
  "circularId": 34582,
  "bibcode": "2023GCN.34582....1B",
  "submittedHow": "email",
  "eventId": "GRB 230826A"
}