GCN Circular 37922
Subject
GRB 241026A: BTA and Zeiss-1000 optical observations
Date
2024-10-28T02:29:19Z (a month ago)
From
Moskvitin Alexander at SAO RAS <mosk@sao.ru>
Via
legacy email
A. S. Moskvitin, A. S. Vinokurov, O. I. Spiridonova (SAO RAS),
A. S. Pozanenko (IKI) report on behalf of the GRB follow-up team.
We observed the field of GRB 241026A (The Fermi GBM team, GCN 37894;
Melandri et al., GCN 37896, Li et al., GCN 37909) with the BTA,
6-m telescope of SAO RAS (equipped with the focal reducer Scorpio-I
and V, Rc filters) and also with the 1-m telescope of SAO RAS,
Zeiss-1000 (equipped with the CCD-photometer and Rc filter)
on October 27.
The OT (Moskvitin et al., GCNs 37899, 37916; Watson et al., GCN 37900;
Zheng & Filippenko GCN 37903; Shrestha et al., GCN 37913; Mo et al.,
GCN 37915; Mohan et al., GCN 37918) is clearly detected in our stacked
frames with the following brightness:
UT_start--UT_end t_mid-T0 exp, s R magnitude R_lim telescope
18:37:41--18:41:24 0.8313 d 4 x 20 21.24 +/- 0.09 23.7 BTA
18:47:40--19:31:31 0.8521 d 8 x 300 21.23 +/- 0.11 23.8 Zeiss-1000
The frames were calibrated against nearby USNO-B1 stars
(R2 magnitudes) and not corrected for MW extinction.