{
  "bibcode": "2022GCN.32898....1R",
  "body": "Amit Kumar Ror, Snehlata, Rahul Gupta, S. B. Pandey, Amar Aryan, Ankur\nGhosh, Dimple, and Kuntal Misra (ARIES) report:\n\n\nWe observed Swift-BAT detected GRB 221028A (Lien et al. GCN 32874) using\nthe 2Kx2K CCD Imager mounted on the 1.3m Devasthal Fast Optical Telescope\n(DFOT) located at the Devasthal observatory of Aryabhatta Research\nInstitute of Observational Sciences (ARIES), India. The observations were\nstarted on 2022-10-28 at 15:17:46, i.e., around 2 hours after the BAT\ntrigger. We have taken multiple frames, each having an exposure time of 300\nsec in the R filter. We did not detect any new source within the XRT error\ncircle in our stacked image. We obtain the following 3-sigma upper limit in\nthe stacked image.\n\n\nDate Start (UT)  T_start-T0 (hours) Filter  Exp time (sec)  Limiting\nmagnitude\n\n===============================================================\n\n2022-10-28 15:17:46    ~2        R        300x6   > 21.5\n\nThe magnitude is not corrected for the Galactic extinction in the direction of\nthe burst. Photometric calibration is performed using the standard stars from\nthe USNO-B1.0 catalog.\n\nThe non-detection of the optical afterglow is consistent with Kumar et al.\nGCNs 32876, 32886; Hu et al. GCN 32878; Lipunov et al. GCN 32879;\nStrausbaugh et al. GCN 32881; Niwano et al. GCN 32883; Watson et al. GCN\nno. 32888; Belkin et al. GCN 32889; Odeh GCN 32894; and Komesh et al. GCN\n32897.\n\nThis circular may be cited.",
  "circularId": 32898,
  "createdOn": 1667200802000,
  "email": "mitturor77894@gmail.com",
  "subject": "GRB 221028A: 1.3m DFOT Optical upper limit",
  "submitter": "Amit Kumar Ror at ARIES  <mitturor77894@gmail.com>",
  "eventId": "GRB 221028A"
}