GCN Circular 46242
Subject
EP261111a: AbAO and Mondy observations, optical afterglow candidate
Event
Date
2026-11-12T23:41:17Z (3 hours ago)
From
Alexei Pozanenko at IKI, Moscow <grb.alex@gmail.com>
Via
email
N. Pankov (IKI), A. Moskvitin (SAO), A. Pozanenko (IKI), R. Ya.
Inasaridze (AbAO), E. Klunko (ISTP), A. Volnova (IKI) report on
behalf of IKI-GRB-FuN:
We observed the field of the Einstein Probe transient EP261111a (Huang
et al., GCN 46226; Li et al., GCN 46235) with AS-32 telescope of
Abastumani Observatory (AbAO) and AZT-33IK of Sayan Solar Observatory
(Mondy) started (UT) 2026-11-11T17:06:33 (t_mid - T0 = 4.3 hours)
and 2026-11-11T20:30:41 (t_mid - T0 =7.6 hours) respectively.
After the subtraction of the PS1 template in the refined FXT error
circle (Li et al., GCN 46235) in the difference image from AS-32 we
found single uncatalogued object with the coordinates of (J2000) R. A.
= 02:52:28.0, Dec. = +44:26:05.3 and brightness of R = 22.0 +/- 0.3.
We do not detect this object in the AZT-33IK stacked image. The
observation details are as follows:
Date UT start t-T0 Exp, Filter Obj Err UL Telescope
(mid,days) (n*s) (3sigma)
2026-11-11 17:06:33 0.17909 60*60 R 22.0 0.3 22.1 AS-32
2026-11-11 20:30:41 0.31635 60*60 R n/d n/d 22.5 AZT-33IK
This preliminary photometry (Vega) is based on nearby SDSS stars
(Lupton 2005 transformation) and not corrected for Galactic
extinction.
We suggest that this object could be the afterglow of EP261111a.
Our results are in agreement with the non-detections by Junjie-Jin et al.,
GCN 46227; Buckley et al., GCN 46230; Eyles-Ferris et al., GCN 46236.