TITLE:   GCN CIRCULAR
NUMBER:  36137
SUBJECT: GRB 240414A: AbAO optical upprer limit
DATE:    24/04/16 14:12:25 GMT
FROM:    Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>

N. Pankov (HSE, IKI), R. Ya. Inasaridze (AbAO), A. Pozanenko (IKI), 
S. Belkin (IKI) report on behalf of GRB-IKI-FuN:

We observed the field of GRB 240414A (Caputo et. al., GCN 36083) at 
redshift z=1.833 (Adami et al., GCN 36085; de Ugarte Postigo et al., GCN 36087) with 70-cm AS-32 telescope of Abastumani Observatory (AbAO). The observations were started on 2024-04-14 (UT) 22:06:33, i.e. ~20 hr since the Swift trigger. We took 117 frames 60 sec each in the R-filter. The optical counterpart (Schneider et al., GCN 36084; Adami et al., GCN 36085; de Ugarte Postigo et al., GCN 36087; Niwano et al., GCN 36088; Lipunov et al., GCN 36095; Dutton et al., GCN 36097; Peretto, GCN 36100; Turpin et al., GCN 36101; Karambelkar et al., GCN 36103; Odeh et al., GCN 36111; Pankov et al., GCN 36113; Siegel & Caputo, GCN 36115; de Ugarte Postigo et al., GCN 36117; Xiong et al., GCN 36130; Wang et al., GCN 36131; Lopresti et al., GCN 36133) is not detected in the stacked image of 113x60 sec. Preliminary photometry is following:

Date       UT_start  t-T0     Filter Exp.   OT    err  UL(3sigma)
                    (mid, days)      (s)
2024-04-14 22:06:33  0.86281  R      113*60 n/d   n.d  21.4

The magnitudes were calibrated with nearby USNO-B1.0 stars.

The result is in agreement with observations carried out by other groups, in particular, with (de Ugarte Postigo et al., GCN 36117) at the similar epoch.