TITLE: GCN CIRCULAR NUMBER: 40510 SUBJECT: GRB 250502A: Tautenburg observations DATE: 25/05/21 14:09:26 GMT FROM: Sylvio Klose at TLS Tautenburg klose@tls-tautenburg.de

K. Kritik, L. Berthel, T. Ranganathan, J. Kahl, S. Schmidl (all FSU Jena), M. Hartmann, B. Stecklum, S. Klose (all Tautenburg) report:

We observed the field of GRB 250502A (Wang et. al., GCN 40313) with the 1.3m Schmidt telescope using the prime focus CCD camera. Observations started on May 2, 2025, at 22:18:13 UT, about 13.5 hrs after the SVOM trigger, at a mean airmass of 2.2.

The optical transient first reported by Rakotondrainibe et. al. (GCN 40315) was clearly detected. Based on 40 min of exposure, at a midtime of 22:38 UT, we measure a preliminary r-band magnitude (AB) of 20.88 +/- 0.20 mag, calibrated against Pan-STARRS DR1. We apologize for the late submission of this circular.

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