TITLE: GCN CIRCULAR NUMBER: 43728 SUBJECT: EP/WXT 01709258378: NOT optical upper limits DATE: 26/02/14 01:29:01 GMT FROM: Laura Cotter at University College Dublin <laura.cotter@ucdconnect.ie> 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: We 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). We 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: r>24.0 z>22.3 These limits are in the AB system, were calibrated using nearby stars from the Pan-STARRS catalog and are not corrected for Galactic extinction. View this GCN Circular online at https://gcn.nasa.gov/circulars/43728. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...