TITLE:   GCN CIRCULAR
NUMBER:  33227
SUBJECT: AT2023avj ZTF Candidate: Assy optical observations
DATE:    23/01/28 14:06:56 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

N. Pankov (HSE, IKI), V. Kim (FAI, Pulkovo Observatory), A. Pozanenko 
(IKI), M. Krugov (FAI), S. Belkin (IKI) report on behalf of GRB IKI FuN:

We observed the Candidate Optical Afterglow ZTF23aaarlti (AT2023avj) 
(Wang et al., GCN 33226) with AZT-20 telescope of Assy-Turgen 
observatory starting on 2023-01-277 (UT) 19:03:41.

We clearly detect the optical source (Wang et al., GCN 33226).

Preliminary photometry of the optical afterglow in a stacked image is 
following

Date       UT start  MJD         Exp.  Filter  OT     Err.  UL(3sigma)
                    (mid, days)  (s)

2023-01-27 19:03:41  59971.80069 75*60 r'(AB)  22.67  0.12   23.9

The photometry is based on nearby PS1 stars.