GCN Circular 37951

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
Not found
 
 
) with the 1-m telescope of SAO RAS, Zeiss-1000
equipped with the CCD-photometer on October 28 and 29.

We detect the OT (Fu et al., GCNs 37840
Not found
 
 
, 37842
Not found
 
 
; Li et al.,
GCNs 37844
Not found
 
 
, 37846
Not found
 
 
; Ror et al., GCN 37845
Not found
 
 
; Zheng et al., GCN 37849
Not found
 
 
;
Moskvitin & Spiridonova, GCN 37850
Not found
 
 
; Pugliese et al., GCN 37852
Not found
 
 
;
Pérez-Fournon et al., GCN 37858
Not found
 
 
; Bochenek & Perley, GCN 37869
Not found
 
 
;
Kumar et al., GCN 37875
Not found
 
 
; Busmann et al., GCN 37877
Not found
 
 
; J-Jin et al.,
GCN 37892
Not found
 
 
; Freeburn et al., GCNs 37911
Not found
 
 
, 37942
Not found
 
 
; Quirola-Vasquez et al.,
GCN 37930
Not found
 
 
) in rebrightening state with the following results.

date    UT_start--UT_end   t_mid-T0  exp, s   R magnitude     R_lim
Oct. 28 19:41:42--23:00:33 7.6758    15 x 300 21.57 +/- 0.08  23.0
Oct. 29 19:55:32--21:03:35 8.6400    12 x 300 21.64 +/- 0.05  23.6

Preliminary photometry was performed in the aperture with r = 2".5,
calibrated against nearby SDSS stars (magnitudes converted with
Lupton 2005 equations) and not corrected for the Galactic extinction.