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GCN Circular 31976

GRB 220430A: Mondy and AbAO optical upper limits
2022-04-30T21:25:52Z (2 years ago)
Alexei Pozanenko at IKI, Moscow <>
N. Pankov (HSE),  S. Belkin (IKI), A. Pozanenko (IKI),  E. Klunko 
(ISTP), R. Ya. Inasaridze (AbAO)  report on behalf of GRB IKI FuN:

We observed the field of Swift GRB 220430A (Ambrosi et al., GCN 31972) 
also detected by AGILE (Ursi  et al., GCN 31975) with AZT-33 telescope 
of Mondy observatory starting on April, 30  (UT) 14:20:53 and AS-32 
telescope of Abastumani observatory starting on April, 30  (UT) 
16:59:12.   We do not detect any sources in the enhanced position of 
Swift-XRT (Osborne et al., GCN 31973) consistent with the observations 
of Swit/UVOT (Ambrosi et al., GCN 31972) and MeerLICHT (Groot et al., 
GCN 31974).
Preliminary photometry of the  combined images is following

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

2022-04-30  14:20:53 0.01953    1*60   R      n/d    n/d    19.5
2022-04-30  14:20:53 0.02613   20*60   R      n/d    n/d    20.5
2022-04-30  16:59:12 0.14962   59*60   R      n/d    n/d    21.0

The photometry is based on nearby USNO-B1.0 stars, R2 magnitude
USNO-B1.0_id R2
0995-0113632 16.50
0995-0113723 15.94
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