TITLE:   GCN CIRCULAR
NUMBER:  35609
SUBJECT: GRB 240123A: Mondy continued optical observations + correction of the GRB name in GCN 35605
DATE:    24/01/23 18:06:11 GMT
FROM:    Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>

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

We continued to observe the afterglow of GRB 240123A (D'Ai et al., GCN 35602) with AZT-33IK telescope of Mondy observatory  in  R-filter originally started on 2024-01-23 (UT) 14:00:48 (Pankov et al., GCN 35605). We confirm the afterglow decay, which  detected previously (D'Ai et al., GCN 35602; Pankov et al., GCN 35605).  

Preliminary photometry of the afterglow is following

Date       UT start  t-T0     Exp.   Filter   OT     Err. UL(3sigma)
                   (mid, days)  (s)

2024-01-23 16:03:39  0.227009 29x120 R        19.87  0.10 21.9

The photometry is based on nearby USNO-B1.0 R2 stars. 

We are also reporting the incorrect name of the GRB in GCN Circular No. 35605. The correct name of the GRB in GCN Circular #3560 should be GRB 240123A.

