TITLE:   GCN CIRCULAR
NUMBER:  34431
SUBJECT: GRB 230812B: Optical observaions from Rozhen Observatory
DATE:    23/08/15 09:34:23 GMT
FROM:    Eslam Elhosseiny at NRIAG <eslam_elhosseiny@nriag.sci.eg>

B. Mihov, L. Slavcheva-Mihova (Institute of Astronomy and NAO, Bulgaria),
Eslam G. Elhosseiny, Ali Takey (National Research Institute of Astronomy and Geophysics (NRIAG), Egypt)
We observed the field of GRB 230812B, detected by Fermi GBM team (GCN 34386; GCN 34387) with the 50/70 cm Schmidt telescope at Rozhen NAO, Bulgaria. The observations started at 19:43 UT of 2023-08-13, 24.75 hours after Fermi detection. We took 18 images with 180 sec in I-band. The stacked image was calibrated in Cousins I-band after transformation from the PS1 catalogue. The counterpart of GRB 230812B was detected with 19.82 +/- 0.15 mag at the position of RA and Dec as 16° 36' 31.5" and 47° 51' 31.81" respectively, which is within the uncertainty of the X-ray position (GCN 34400).