TITLE: GCN CIRCULAR NUMBER: 37346 SUBJECT: GRB 240828B: SAO RAS optical upper limit DATE: 24/08/30 00:10:12 GMT FROM: Moskvitin Alexander at SAO RAS mosk@sao.ru
A. S. Moskvitin and O. I. Spiridonova (SAO RAS) report on behalf of the GRB follow-up team.
We observed the field of GRB 240828B (Le Provost et al., GCN 37318) with the SAO RAS 1-meter telescope Zeiss-1000 equipped with the CCD-photometer on August 29, 19:36:46 -- 20:00:01 UT (t_mid - T0 = 30.594 hours = 1.2748 days). We obtained several images in Rc band with a total exposure of 1040 seconds.
Within the XRT error circle (Page et al., GCN 37334) we didn't detect any source down to a limiting magnitude of R_lim = 21.0 as well as KAIT team (Zheng et al., GCN 37345).
The field was calibrated against nearby SDSS stars (magnitudes converted with Lupton 2005 equations) and not corrected for the Galaxy extinction.
View this GCN Circular online at https://gcn.nasa.gov/circulars/37346. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...