{
  "createdOn": 1763499390031,
  "format": "text/plain",
  "body": "Malte Busmann (LMU), Xander J. Hall (CMU), Brendan O'Connor (CMU), Daniel Gruen (LMU), and Antonella Palmese (CMU) report:\n\nWe observed the candidate Swift X-ray sources GRB 251117a_X6 and X7 (Evans et al., GCN 42730), as potential counterparts to GRB 251117A (Fermi GBM team, GCN 42719; Airasca et al., GCN 42729; Wang et al., GCN 42731; DeLaunay et al., GCN 42732; Arya et al., GCN 42740) with the Three Channel Imager (3KK) at the Fraunhofer Telescope at Wendelstein Observatory (FTW) in the r, i and J band simultaneously for 10 x 180 s starting at 2025-11-18T17:36:17 UT (1.22 days after the trigger). \n\nWe performed difference imaging with archival images from Legacy Survey and do not detect any new sources down to\n\nr > 23.9 AB mag (3 sigma).\n\nThe magnitudes are calibrated against the PS1 catalog and not corrected for Galactic extinction.\n\nWe thank Michael Schmidt from the Wendelstein Observatory for obtaining these observations.",
  "circularId": 42744,
  "submitter": "Malte Busmann at Ludwig-Maximilians-Universität München <m.busmann@physik.lmu.de>",
  "bibcode": "2025GCN.42744....1B",
  "submittedHow": "web",
  "eventId": "GRB 251117A",
  "subject": "GRB 251117A: FTW Observations of Swift candidate X-ray sources"
}