GCN Circular 42763
Subject
EP251118a: FTW optical and NIR observations
Event
Date
2025-11-19T15:14:34Z (3 days ago)
From
Malte Busmann at Ludwig-Maximilians-Universität München <m.busmann@physik.lmu.de>
Via
Web form
Malte Busmann (LMU), Xander J. Hall (CMU), Brendan O'Connor (CMU), Daniel Gruen (LMU), and Antonella Palmese (CMU) report:
We observed the counterpart of EP251118a (Jiang et al., GCN 42749; Malesani et al., GCN 42751; Shi et al., GCN 42754; An et al., GCN 42756) with the Three Channel Imager (3KK) at the Fraunhofer Telescope at Wendelstein Observatory (FTW) in the r, i, and J bands simultaneously for 5 x 180 s starting at 2025-11-19T04:06:56 UT (0.48 days after the trigger). The counterpart is detected in all bands. Using Legacy Survey templates for difference imaging, we measure an r-band magnitude of
r = 20.56 +/- 0.04 AB mag.
Our measurements are consistent with the reports by Malesani et al. (GCN 42751), Lipunov et al. (GCN 42755), Belkin et al. (GCN 42758), and Yadav et al. (GCN 42760).
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.