Malte Busmann (LMU), Daniel Gruen (LMU), Brendan O’Connor (CMU), Julius Gassert (LMU), Lei Hu (CMU), Antonella Palmese (CMU), Christoph Ries (LMU), Arno Riffeser (LMU/MPE), Michael Schmidt (LMU), Ananya Shankar (LMU):
We observed the position of GRB 231104A (Fermi GBM team, GCN 34937; Page et al., GCN 34938) with the 2m Fraunhofer telescope at Wendelstein Observatory, Germany. Observations were obtained using the 3kk imager in the r, z, and K bands simultaneously starting on 2023-11-06 at 12:09:53 UT with a total exposure of 6,021 seconds.
At the position of the XRT source (Goad et al., GCN 34940) we do not detect any source within 15” to depth r> 23.6 and K>21.0 AB mag at 2.4 days after the GRB trigger. The magnitudes are not corrected for Milky Way extinction and the photometry was calibrated against nearby stars in the PS1 and 2MASS catalogs.
We thank the staff of the Wendelstein Observatory for obtaining these observations.