{
  "eventId": "GRB 250430A",
  "format": "text/plain",
  "subject": "GRB 250430A: Bassano Bresciano Observatory upper limit",
  "submitter": "Ulisse Quadri at Bassano Bresciano Observatory <osservatoriobassano@gmail.com>",
  "circularId": 40303,
  "bibcode": "2025GCN.40303....1Q",
  "body": "U.Quadri, L.Strabla and P.Madurini (Bassano Bresciano Astronomical Observatory)\n\nMembers of: \nGRB/UAI - Gamma ray Burst section of Unione Astrofili Italiani.\nAAVSO - American Association of Variable Star Observers.\nGAC - Gruppo Astrofili Cremonesi.\n\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 imaged the field of GRB 250430A detected by Swift with the robotic telescope of (IAU station 565) Bassano Bresciano Observatory, Italy.\nThe observations started 5h 01m after the GRB trigger with our Newton telescope D=250 mm F/D=4.8.\n\nWe co-added 2 series of 150 exposures of 30 sec each.\n\nStart T0+   End T0+     Rc lim.   Err.\n 5h 01m     6h 30m       20.3   +/- 0.2\n 6h 31m     8h 01m       20.3   +/- 0.2\n\nWe did not found any optical uncatalogued object within the Swift error circle.\n\nOur upper limit is consistent with other observations reported by K. S. Kawabata et al. (GCN Circular 40294), Mohammad Odeh et al. (GCN Circular 40295), Andrea Saccardi et al (GCN Circular 40301), H. Hagio et al. (GCN Circular 40302).\n\nMagnitudes were estimated with the pan-STARRS cat and are derived using Lupton (2005) equations.\n\nNot corrected for galactic dust extinction.\n\nReference:\nhttp://www.osservatoriobassano.altervista.org\n\nThe message may be cited.",
  "createdOn": 1746106413820,
  "submittedHow": "web"
}