TITLE:   GCN CIRCULAR
NUMBER:  25682
SUBJECT: GRB 190829A observations in CrAO, photometry of the SN
DATE:    19/09/07 10:59:13 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

A. Volnova (IKI), V. Rumyantsev (CrAO),  A. Pozanenko (IKI), S. Belkin 
(IKI), E. Mazaeva (IKI) report on behalf of IKI GRB FuN collaboration:

We are observing the optical afterglow (Xu et al., GCN 25555;  Lipunov 
et al., GCN 25558; Kumar et al. GCNC 25560) of GRB 190829A (Fermi team, 
GCN 25551; Dichiara et al., GCN 25552) at 0.0785 (Valeev et al., GCN 
25565). Observations of the OA with ZTSh 2.6m telescope of CrAO started 
on Aug. 30 and continued up to Sep. 6 in B and R filters.

Using masked subtraction we can compare the brightness of the OA in 
different epochs. The OA is steady fading between Aug. 30 and Sep. 2. 
Between the two epochs (2019-09-02T00:46:30 and 2019-09-06T00:40:50)  we 
clearly observe brightening of the OA (by 1.8 magnitude in R-filter) 
which corresponds to the rising Supernova (Bolmer et al., GCN 25651; 
Perley et al., GCN 25657; Terreran et al., GCN 25664; de Ugarte Postigo 
et al., GCN 25677).