{
  "bibcode": "2025GCN.42651....1G",
  "submittedHow": "web",
  "format": "text/plain",
  "createdOn": 1762965938937,
  "body": "\nAnshika Gupta, Kumar Pranshu, Debolina Kar, Dhruv Jain, Pankaj Pawar and Kuntal Misra (ARIES) report:\n\nWe observed the field of GRB251111A detected by SVOM (Cheng et al. 2025, GCN 42637), with the 1.3m Devasthal Fast Optical Telescope (DFOT), located at the Devasthal Observatory of the Aryabhatta Research Institute of Observational Sciences (ARIES), India. The observations were started on 2025-11-11 at 15:37:41 UT, i.e., ~10.45 hours after the SVOM trigger. We have taken multiple frames with an exposure time of 300 s in the R filter. We stacked the images after the alignment. We could not detect the optical emission in our stacked image within the error box of SVOM/COLIBRÍ (López-Cámara et al. 2025, GCN 42638) & Swift-XRT (Campana et al. 2025, GCN 42648). We obtain the following 3-sigma upper limit in the stacked image:\n\nDate Start_UT T_start-T0 (hour) Filter  Exp time (s)  Magnitude\n===============================================================\n2025-11-11  15:37:41    ~10.45    R     300s*24     >23.2\n\nThe upper limit of the burst is consistent with López-Cámara et al. 2025 (GCN 42638); Wu et al. 2025 (GCN 42639); Zheng  et al. 2025 (GCN 42640); Wu et al. 2025 (GCN 42641); Ma et al. 2025 (GCN 42647).\n\nThe magnitude is not corrected for the Galactic extinction in the direction of the burst. Photometric calibration is performed using the standard stars from the USNO-B1.0 catalogue. \n \n\n",
  "eventId": "GRB 251111A",
  "subject": "GRB251111A: 1.3m DFOT optical upper limit",
  "circularId": 42651,
  "submitter": "ANSHIKA GUPTA at ARIES <anshika05180@gmail.com>"
}