{
  "subject": "GRB 250625A: AbAO and INASAN Kislovodsk Optical Observations",
  "eventId": "GRB 250625A",
  "submittedHow": "web",
  "bibcode": "2025GCN.40848....1P",
  "createdOn": 1751025309593,
  "circularId": 40848,
  "submitter": "Nicolai Pankov at HSE, IKI RAS <colinsergesen@gmail.com>",
  "format": "text/plain",
  "body": "N. Pankov (HSE, IKI), R. Ya. Inasaridze (AbAO), A. Tarasenkov (INASAN), A. Pozanenko (IKI) report on behalf of IKI-GRB-FuN:\n\nWe observed the field of GRB 250625A (Fermi GBM Team, GCN 40824; Ferro et al., GCN 40825; Beardmore et al., GCN 40827; Dichiara et al., GCN 40835; Di Lalla et al., GCN 40836) using the 0.7-meter AS-32 telescope of Abastumani Observatory (AbAO) and the 0.5-meter RC-500 telescope of INASAN Kislovodsk Observatory. The observations at AbAO started on 2025-06-25 at 17:41:35 UT and consisted of 71*60 sec exposures. The observations at RC-500  were carried out between 2025-06-25 18:19:40 UT and 2025-06-26 00:09:04 UT using 120 sec exposures. We do not detect the optical afterglow reported/followed by (Moskvitin et al., GCN 40828, Xin et al., GCN 40830; Malesani et al., GCN 40831; Lipunov et al., GCN 40826/40832; Zhu et al., GCN 40834, Fortin et al., GCN 40837; Adami et. al, GCN 40838; Brosio et. al, GCN 40839; Breeveld & Ferro, GCN 40840; WU et. al, GCN 40842; Ruocco et. al, GCN 40843; de Ugarte Postigo et. al, GCN 40846) in the R-band co-add images. \nThe preliminary photometry is as follows:\n\nDate       UT start      t-T0     Exp.    Filter  OT     Err.      UL     Telescope\n                     (mid, days)  (n*s)                         (3sigma)\n2025-06-25 17:41:35    0.09176    71*60     R     n/d    n/d      20.0       AS-32\n2025-06-25 18:38:08    0.14735    59*120    R     n/d    n/d      21.5      RC-500\n\nThe photometry has calibrated using stars from USNO-B1.0 (see Moskvitin et al., GCN 40828) and has not corrected for the Galactic extinction."
}