GCN Circular 45951
Subject
GRB 261011A: SAO RAS and AbAO optical observations
Event
Date
2026-10-14T16:33:53Z (a day ago)
From
Alexander Moskvitin at SAO RAS <mosk@sao.ru>
Via
email
A. Moskvitin (SAO), A. Volnova (IKI), V. Goranskij (SAI MSU, SAO),
V. Vlasyuk (SAO), R. Inasaridze (AbAO), N. Pankov (IKI), A. Pozanenko
(IKI),
on behalf of the SAO GRB follow-up team and the IKI-GRB-FuN report.
We observed the field of GRB 261011A (Huang et al., GCN 45895;
Cenko et al., GCN 45896; Ridnaia et al., GCN 45924; Barthelmy et al.,
GCN 45930; Page et al., GCN 45933; Melandri et al., GCN 45934;
Luo et al., GCN 45939) at redshift z = 2.407 (Pérez-García et al.,
GCN 45931; Monsalves et al., GCN 45920) with the SAO RAS 1-m Zeiss-1000,
0.5-m AS-500(2) and AbAO 0.7-m AS-32 telescopes on October 11.
The OT (Cenko et al., GCN 45896; O'Neill et al., GCN 45897; Fu et al.,
GCN 45898; Izzo, GCNs 45899; 45909; Wu et al., GCN 45900; Shi et al.,
GCN 45903; Aryan et al., GCN 45904; Saikia et al., GCN 45907;
Bochenek and Perley, GCN 45914; Li et al., GCN 45915; Zhao et al.,
GCN 45916; Takahashi et al., GCN 45917; Cheng et al., GCN 45922;
also observed in NIR by Huang et al., GCN 45913) is marginally
detected only in the Zeiss-1000 stacked frame.
Details of the observation are the following.
Date UT start t-T0 Exp, Filter Obj Err UL
Site/Telescope
(mid,days) (n*s) (3sigma)
2026-10-11 20:22:07 0.29806 117*30 R n/d 21.6
SAO/AS-500(2)
2026-10-11 20:56:50 0.30510 3*300 Rc 21.9 0.3 22.0
SAO/Zeiss-1000
2026-10-11 21:01:57 0.32050 49*60 R n/d 20.9
AbAO/AS-32
This preliminary photometry (Vega) is based on nearby SDSS stars
(Lupton 2005 transformation) and not corrected for Galactic extinction.