TITLE:   GCN CIRCULAR
NUMBER:  24712
SUBJECT: GRB 190530A: Mondy and AbAO optical observations
DATE:    19/06/02 09:53:20 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

S. Belkin (IKI),  E. Klunko (ISTP), R. Ya. Inasaridze (AbAO), A. 
Pozanenko (IKI), V.R. Ayvazian (AbAO), E. Mazaeva (IKI), A. Volnova 
(IKI) report on behalf of IKI GRB FuN collaboration:

We continue observations the  optical afterglow (Lipunov et al., GCN 
24680, 24693 and also e.g. Kann et al., GCN 24684; Melandri et al., GCN 
24689; Heintz et al., GCN 24686; Lzzo et al., GCN  24687; Xin et al., 
GCN   24688; Watson et al., GCN  24690; Xin et al., GCN 24697)  of the 
Fermi GRB 190530A (Fermi GBM Team, GCN  24676; Longo et al., GCN 
24679) with   AZT-33IK telescope of Sayan observatory (Mondy) and AS-32 
(0.7m) telescope of Abastumani Observatory. The afterglow is clearly 
visible in stacked images. Preliminary photometry of the afterglow is 
following.

Date        UT start t-T0   Filter Exp.   OT    Err. UL
                      (mid, days) (s)

2019-06-01  15:35:00 2.23638  R    29*60 19.62  0.07  21.2
2019-06-01  17:38:57 2.31769  R    30*60 19.70  0.14  20.6

The photometry is based on the nearby USNO-B1.0 stars

USNO-B1.0_id R2
1255-0157926 13.35
1254-0159410 12.63
1255-0157793 13.56

The photometry might be influenced by nearby optical source presented in 
    Pan-STARRS DR1 catalog (ID 150571205309266249) mentioned in (Lipunov 
et al., GCN 24680).