TITLE:   GCN CIRCULAR
NUMBER:  37850
SUBJECT: EP241021a: SAO RAS optical observations
DATE:    24/10/23 22:53:51 GMT
FROM:    Moskvitin Alexander at SAO RAS <mosk@sao.ru>

A. S. Moskvitin and O. I. Spiridonova (SAO RAS), report
on behalf of the GRB follow-up team:

We observed the field of  X-ray transient EP241021a (Hu et al.,
GCN 37834) with the 1-m telescope of SAO RAS equipped with
CCD-photometer. We obtained 9 x 300 sec. images in Rc band
on October 23, 19:27:12--20:17:25 UT (t_mid - T0 = 2.6141 days).

We clearly detect the OT (Fu et al., GCNs 37840, 37842; Li et al.,
GCNs 37844, 37846; Ror et al., GCN 37845; Zheng et al., GCN 37849)
in our stacked frame with the brightness of R = 21.81 +/- 0.06
calibrated against nearby SDSS stars (magnitudes converted with
Lupton 2005 equations) and not corrected for the Galactic extinction.