{
  "subject": "EP/WXT 01709258378: NOT optical upper limits",
  "createdOn": 1771032541767,
  "bibcode": "2026GCN.43728....1C",
  "body": "L. Cotter (UCD), G. Corcoran (UCD), A. Martin-Carrillo (UCD), D. B. Malesani (DAWN/NBI and Radboud), F. E. Bauer (SSI and UTA) and P. G. Jonker (Radboud)  report on behalf of a larger collaboration:\n\nWe observed the field of the fast X-ray transient WXT 01709258378 using the Nordic Optical Telescope (NOT) equipped with the ALFOSC camera. Observations were obtained in the SDSS r (3x300 s) and z (5x200 s) bands, starting on 2026-02-13 at 23:08:39 UT (3.17 hours after the WXT trigger).\n\nWe do not find any new, uncatalogued sources within the EP/WXT uncertainty region. From the stacked images we obtain the following 3-sigma upper limits:\n\nr>24.0\nz>22.3\n\nThese limits are in the AB system, were calibrated using nearby stars from the Pan-STARRS catalog and are not corrected for Galactic extinction.\n",
  "submitter": "Laura Cotter at University College Dublin <laura.cotter@ucdconnect.ie>",
  "format": "text/plain",
  "circularId": 43728,
  "submittedHow": "web"
}