TITLE:   GCN CIRCULAR
NUMBER:  38913
SUBJECT: EP250111a: Mondy optical observation
DATE:    25/01/11 23:14:49 GMT
FROM:    Alexei Pozanenko at IKI, Moscow <grb.alex@gmail.com>

 N. Pankov (HSE, IKI), A. Pozanenko (IKI), E. Klunko (ISTP) report on
behalf of the IKI GRB FuN collaboration:

We performed optical observations of the field of EP250111a (Zhao et. al,
GCN 38905; Kennea et. al, GCN 38910) in the R filter with the 1.5-meter
AZT-33IK telescope of the Sayan Solar Observatory (Mondy). The observations
started on 2025-01-11 11:57 UT, i.e. ~0.46 days since trigger. We detect
the optical source proposed by Fu et. al, GCN 38906 as an optical transient
of EP250111a. Preliminary photometry of the source is the following:

Date UT start t-T0 Exp. Filter OT Err. UL(3sigma)
(mid, days) (s)
2025-01-11 11:57:42 0.46301 51*70 R 21.20 0.15 21.4