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GCN Circular 34251

GRB 230723B: Optical afterglow candidate from CAHA
2023-07-24T17:05:45Z (a year ago)
Antonio de Ugarte Postigo at OCA <>
J.F. Agui Fernandez (IAA-CSIC), A. de Ugarte Postigo (OCA/CNRS), C.C. Thoene (ASU-CAS), M. Blazek and Ana Guijarro Roman (CAHA) report:

After XRT delivered its refined analysis and updated GRB localisation (Osborne et al. GCN 34248) we noticed that the new localisation has very little overlap with the fist one. The revised localisation is no longer consistent with the object mentioned in our previous GCN (Agui Fernandez et al. GCN 34241). However, within the new localisation circle and outside the original one, we detect an object at coordinates (J2000): 16:41:30.65 -5:20:04.5 with an AB magnitude of i =  22.4+/-0.2 mag as compared to PanSTARRS field objects. No object is detected in PanSTARRS at this position. Further observations will be needed to confirm the object variability and its possible identification as the optical counterpart of GRB 230723A.
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