TITLE: GCN CIRCULAR NUMBER: 35370 SUBJECT: GRB 231215A: GAD Observatory, La Spezia, Italy upper limit; DATE: 23/12/16 11:12:34 GMT FROM: Claudio Lopresti <cl3lop@gmail.com> Claudio Lopresti (Gruppo Astronomia Digitale - GAD Observatory, La Spezia, Italy) in collaboration with: M.G. Dainotti (National Astronomical Observatory of Japan), Y. Niino (Tokyo University, Institute of Astronomy), K. Kalinowski (Aarhus University, Department of Physics and Astronomy), B. De Simone (Universita' degli Studi Di Salerno), Unione Astrofili Italiani (UAI) report: We imaged the field of GRB 231215A (trigger=1202522) with the telescope LX200 12” of GAD Observatory, La Spezia, Italy Member of: UAI/SSV - Unione Astrofili Italiani/sezione stelle variabili, GRB section. GAD - Gruppo Astronomia Digitale. The observations started 551 min after the GRB trigger, with a Shmidt-Cassegrain telescope D=304 mm with reducer F/D=4.75. Weather conditions were medium. The observation with a series of 60 sec exposures started at 2023-12-15 18:58:47 UT We co-added 230 exposures of 60 sec each. Start T0+ End T0+ R lim 551 min 815 min 17,99 We did not found any optical counterpart in 00:38:58.02 +57:38:47.2 position and in the error box of the XRT candidate. ref.: P. D'Avanzo et al. GCN 35343, P.A. Evans et al. GCN 35345 Magnitudes were estimated with the Gaia EDR3 cat. and are not corrected for galactic dust extinction. Reference: https://www.parcodellestelle.com/ The message may be cited. View this GCN Circular online at https://gcn.nasa.gov/circulars/35370. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...