TITLE: GCN CIRCULAR NUMBER: 43181 SUBJECT: EP251220a: FTW optical and NIR observations DATE: 25/12/22 13:41:22 GMT FROM: Malte Busmann at Ludwig-Maximilians-Universität München <m.busmann@physik.lmu.de> Malte Busmann (LMU), Xander J. Hall (CMU), Julius Gassert (LMU/CMU), Brendan O'Connor (CMU), Daniel Gruen (LMU), and Antonella Palmese (CMU) report: We observed the counterpart of EP251220a (Liu et al. GCN 43162, Sánchez Álvarez et al. GCN 43167, Liu et al. GCN 43172) with the Three Channel Imager (3KK) at the Fraunhofer Telescope at Wendelstein Observatory (FTW) in the r, i, and J-band simultaneously for 5 x 180 s starting at 2025-12-21T18:45:36 UT (1.43 days after the trigger). We detect the counterpart in the r and i-band and measure an r-band magnitude of r = 21.94 +/- 0.12 AB mag. Our measurements are consistent with the reports by Lipunov et al. (GCN 43163), Sánchez Álvarez et al. (GCN 43167), Kumar et al. (GCN 43169), and Rakotondrainibe et al. (GCN 43170). The magnitude is calibrated against the PS1 catalog and not corrected for Galactic extinction. We thank Michael Schmidt from the Wendelstein Observatory for obtaining these observations. View this GCN Circular online at https://gcn.nasa.gov/circulars/43181. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...