GCN Circular 30525
Subject
GRB 210726A: CAHA 2.2m telescope optical limit
Date
2021-07-26T22:25:14Z (3 years ago)
From
Youdong HU at IAA-CSIC <huyoudong072@hotmail.com>
Y.-D. Hu, T.-R. Sun, E. Fernandez-Garcia, A. J. Castro-Tirado M. D. Caballero-Garcia, M. A. Castro Tirado (IAA-CSIC), A. Gardini and I. Hermelo (CAHA) on behalf of a larger collaboration, report:
Following the detection of GRB210726A by Swift (Bernardini et al. GCNC 30523), we triggered the 2.2m CAHA telescope (+ CAFOS) at the Calar Alto Observatory (Almeria, Spain). A series of i-band images were gathered starting on July 26, 20:23 UT (i.e. 1.07 h post trigger). On the co-added image (15 x 60s), no optical object is detected down to 21.9 mag at the X-ray afterglow position reported by Swift/XRT (Osborne et al. GCNC 30524).
We thank the staff at Calar Alto observatory for their excellent support.