TITLE: GCN CIRCULAR NUMBER: 39169 SUBJECT: EP250205a/GRB 250205A: FTW optical and NIR observations of the counterpart DATE: 25/02/06 13:31:09 GMT FROM: Malte Busmann at Ludwig-Maximilians-Universität München <m.busmann@physik.lmu.de> Malte Busmann (LMU), Daniel Gruen (LMU), Brendan O’Connor (Carnegie Mellon U.) and Antonella Palmese (Carnegie Mellon U.) report: We observed the counterpart of EP250205a/GRB 250205A (Saccardi et al., GCN 39154; Gompertz et al., GCN 39156; Schneider and Adami, GCN 39157; Gompertz et al., GCN 39158; Palmerio et al., GCN 39159; de Ugarte Postigo et al., GCN 39160; Kennea et al., GCN 39161; Watson et al., GCN 39162; Liu et al., GCN 39165; Breeveld et al., GCN 39168) with the Three Channel Imager (3KK) at the Fraunhofer Telescope Wendelstein (FTW) in the r, i and J band simultaneously for 40 x 180 s starting at 2025-02-05T23:04:26 UT (1.66 hours after the trigger). We detect the counterpart in the single exposures. In the first exposure at r = (21.95 +/- 0.17) mag i = (21.26 +/- 0.13) mag J = (20.25 +/- 0.16) mag. The r- and i-band manitudes are calibrated against the PS1 catalog and the J-band is calibrated with the 2MASS Catalog. All magnitudes are provided in the AB system and are not corrected for Galactic extinction. We thank Christoph Ries from the Wendelstein Observatory for obtaining these observations. View this GCN Circular online at https://gcn.nasa.gov/circulars/39169. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...