{
  "subject": "GRB 231216A: Osservatorio Astronomico Nastro Verde upper limit",
  "eventId": "GRB 231216A",
  "submitter": "Nello Ruocco at Osservatorio Nastro Verde - Sorrento (Naples) - Italy - MPC Code C82 <osservatorionastroverde@gmail.com>",
  "submittedHow": "web",
  "bibcode": "2023GCN.35394....1R",
  "circularId": 35394,
  "createdOn": 1702843580829,
  "body": "Nello Ruocco at Osservatorio Nastro Verde - Sorrento (Naples) - Italy\nin a large collaboration with:\nM.G. Dainotti (National Astronomical Observatory of Japan), \nY. Niino (Tokyo University, Institute of Astronomy), \nK. Kalinowski (Aarhus University, Department of Physics and Astronomy),\nB. De Simone (Universita' degli Studi Di Salerno)\nreport: \n\nWe image the field of GRB 231216A detected by Swift Burst Alert Telescope (BAT)(trigger 1202749)\nwith telescope of Nastro Verde Observatory - Sorrento (Naples), Italy. Member of: \nAAVSO - American Association of Variable Star Observers.\nUAI/SSV - Unione Astrofili Italiani/sezione stelle variabili.\nAstroCampania Associazione\n\nThe observations started at 20:15 UT of  2023/12/16, after 1,40 hours after the GRB trigger, with principal telescope  SC 0.35 f/10 with focal reduced + CCD Sbig ST10 XME\nI took 20 image of 60 sec each. All images are unfiltered, calibrated with masterdark and masterflat,stacked with Tycho Tracker software\nWe have not detected any clearly visible sources, up to 19.5th magnitude  in a sky with light clouds and gusts of wind.\nStart T0+                End T0+        Rlim\n20:15:25 UT            20:36:38 UT      19.5\n\nWe did not found any optical counterpart in the error box of the XRTcandidate.\nT. Sbarrato et al. GCN 35378\n\n\n\nMagnitudes were estimated with the Gaia DR2 cat. and \nare not corrected for galactic dust extinction.\n\n\n\nThe message may be cited."
}