TITLE:   GCN CIRCULAR
NUMBER:  27820
SUBJECT: GRB 200524A: Kitab observatory afterglow observations
DATE:    20/05/25 15:37:06 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

S. Belkin (IKI), A. Novichonok (Petrozavodsk State University, KIAM), A. 
Pozanenko (IKI),  E. Mazaeva  (IKI), A. Volnova (IKI), I. Molotov 
(KIAM), Sh. Ehgamberdiev (UBAI) report on behalf of IKI-GRB-FuN:

We observed Fermi-LAT detected localization area of GRB 200524A (Dirirsa 
et al., GCN 27797; see also Pookalil et al., GCN 27809; Capalbi  et al., 
GCN 27811; Gupta et al., GCN 27818) with   Kitab-ISON RC-36  telescope 
starting on 2020-05-24 (UT) 19:07:41. In a stacked image in Clear filter 
(CR) we marginally detected optical afterglow discovered by ZTF (Ho et 
al., GCN 27799) and confirmed by several observations (Kumar et al. GCN 
27800; (Kumar et al., GCN 27800; Rumyantsev et al., GCN 27802; Sanwal et 
al., GCN 27803; Perley et al., GCN 27805; Kumar et al., GCN 27806; de 
Ugarte Postigo et al., GCN 27807; Blazek et al., GCN 27810; Ogawa et 
al., GCN 27813; Izzo, GCN 27817). Preliminary photometry is following

Date,      UT start, t-T0,   Exp., Filter,  OT,   Err., UL
                     (mid, days)
2020-05-24 19:07:41  0.60673 60*60 CR       20.48 0.25  21.0

The photometry is based on nearby USNO-B1.0 stars
USNO-B1.0_id R2
1508-0206198 15.78
1509-0204466 16.48
1509-0204434 16.53