{
  "bibcode": "2021GCN.29558....1Z",
  "body": "WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on\n\nbehalf of the KAIT GRB team:\n\n\nThe 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at\n\nLick Observatory, responded to Swift GRB 210222B (Gropp et al.,\n\nGCN 29545) starting at ~0.44 days after the burst. A total of\n\n30x60s images were obtained in the clear (roughly R) filters.\n\nWe do not detect the optical afterglow (Gropp et al., GCN 29545;\n\nHu et al., GCNC 29546; Strausbaugh et al., GCNC 29547; Mong et al.,\n\nGCNC 29548; Perley, GCNC 29549; Agui Fernandez et al., GCNC 29552;\n\nLipunov et al., GCNC 29554; Jelinek et al., GCN 29557) in the\n\nco-add images, down to a limiting magnitude of ~20.0 mag calibrated\n\nto the USNOB1.0 catalog.",
  "circularId": 29558,
  "createdOn": 1614098881000,
  "email": "weikang@berkeley.edu",
  "subject": "GRB 210222B: KAIT Optical Upper Limit",
  "submitter": "Weikang Zheng at UC Berkeley  <weikang@berkeley.edu>",
  "eventId": "GRB 210222B"
}