GCN Circular 42896
Subject
GRB 251126A: SAO RAS optical observations
Event
Date
2025-11-29T17:15:20Z (2 days ago)
From
Alexander Moskvitin at SAO RAS <mosk@sao.ru>
Via
Web form
V. Goranskij (SAI MSU, SAO RAS), A. Moskvitin (SAO RAS),
V. Shergin (SAO RAS), A. Volnova (IKI), N. Pankov (HSE, IKI),
A. Pozanenko (IKI) report on behalf of IKI-GRB-FuN
and GRB follow-up team.
We observed the field of the Swift GRB 251126A (Caputo et al.,
GCN 42843; Evans, GCN 42845; Goad et al., GCN 42851; Page et al.,
GCN 42860; Barthelmy et al., GCN 42876) with the Zeiss-1000
1m telescope of the SAO RAS on November 28/29 night.
We obtained a series of 300 and 600 sec. images in Rc band
under a good weather conditions and FWHM of about 1".8.
The optical afterglow (Swain, GCN 42844; Fu et al., GCN 42848;
Reguitti et al., GCN 42849; Broens et al., GCN 42850; Anguloet al.,
GCN 42855; Pulido-Torres et al; GCN 42856; Gupta et al., GCN 42857;
Cotter et al., GCN 42858; Seki et al., GCN 42859; Volnova et al.,
GCN 42861; Breeveld and Caputo, GCN 42863; Gupta et al., GCN 42864;
Burkhonov et al., GCN 42866; Maksut et al., GCN 42868;
Moskvitin et al, GCN 42870; Adami et al., GCN 42871; Pankov et al.,
GCN 42875) is clearly detected in the stacked frame.
We report preliminary brightness of the optical afterglow.
Date UT start t-T0 Exp. Filter OT Err. UL
(mid,days) (n*s) (3sigma)
2025-11-28 22:35:56 2.2236 8*300+4*600 Rc 23.15 0.18 23.7
The photometry is based on nearby stars from the USNO-B1 catalogue
(R2 magnitudes)and is not corrected for the Galactic extinction.