TITLE:   GCN CIRCULAR
NUMBER:  43881
SUBJECT: EP260227a: FTW optical and NIR observations
DATE:    26/02/28 20:17:24 GMT
FROM:    Julius Gassert at Ludwig-Maximilians-Universität München <julius.gassert@campus.lmu.de>

Julius Gassert (LMU/CMU), Malte Busmann (LMU), Christoph Ries (LMU), Xander J. Hall (CMU), Brendan O’Connor (CMU), Daniel Gruen (LMU), and Antonella Palmese (CMU) report:

We observed the optical counterpart (Eyles-Ferris et al., GCN 43867; Li et al., GCN 43868; Fu et al., GCN 43873; Mandarakas et al., GCN 43874; Eyles-Ferris & Tanvir, GCN 43875; Malesani et al., GCN 43876; Eyles-Ferris et al., GCN 43877; Strausbaugh et al, GCN 43879, Bochenek et al. GCN 43880) of EP 20260227a (Wang et al., GCN 43869) with the Three Channel Imager (3KK) at the Fraunhofer Telescope at Wendelstein Observatory (FTW) in the r, i, and J bands for 19x 180s, starting at 2026-02-28T04:21:12 (0.34 days after the trigger). We detect the counterpart in all bands and measure an r-band magnitude of

r = 21.69 +/- 0.10 AB mag

The magnitude is calibrated against the PS1 catalog and not corrected for Galactic extinction.