{
  "bibcode": "2018GCN.22617....1M",
  "body": "E. Mazaeva (IKI),  L. Elenin (KIAM),  A. Pozanenko (IKI), A. Volnova \n(IKI), I. Molotov (KIAM)  report on behalf of larger GRB  follow-up \ncollaboration:\n\nWe observed the field of the Swift  short burst GRB 180402A (Lien et \nal., GCN 22580) with 0.4-m telescope of ISON-NM observatory starting on \nApr., 02 (UT) 09:45:39, i.e. 40 seconds after the burst trigger. We \nobtained 4 unfiltered images of 30 s exposure each. We do not detect any \nsource within XRT error circle (Lien et al., GCN 22580). Upper limits \nare following.\n\nDate      start (Ut)   t-T0         Exp.     UL (3sigma)\n                       (mid.,sec)    (s)\n2018-04-02 09:45:39   55            1*30     14.5\n2018-04-02 09:45:39  133            4*30     15.0\n\nThe photometry is based on nearby USNO-B1.0 stars (R2 magnitudes).",
  "circularId": 22617,
  "createdOn": 1523220042000,
  "email": "apozanen@iki.rssi.ru",
  "subject": "GRB 180402A: ISON-NM early optical limits",
  "submitter": "Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>",
  "eventId": "GRB 180402A"
}