TITLE:   GCN CIRCULAR
NUMBER:  45673
SUBJECT: EP260920b: LCO observations
DATE:    26/09/21 09:28:18 GMT
FROM:    Rob Eyles-Ferris at U of Leicester <raje1@leicester.ac.uk>

R. A. J. Eyles-Ferris (Leicester), P. G. Jonker (Radboud), J. Chácon (PUC), G. Corcoran (UCD), J. A. Quirola-Vasquez (Radboud) report on behalf of a larger collaboration:

We observed the field of the fast X-ray transient EP260920b (Ni et al., GCN 45664; Yang et al., GCN 45670) using using an LCO 1m telescope located at the Cerro Tololo Interamerican Observatory (Chile) equipped with the SINISTRO instrument. We obtained 11x300 s exposures in the SDSS r-band starting at 2026-09-21 01:13:47 (~11.1 hours after the trigger).

The counterpart (Liu et al., GCN 45668; García-García et al., GCN 45669; Li et al., GCN 45671) is detected in our images at a magnitude of r = 21.38 +/- 0.13 at t_mid - t0 = 11.57 hours. Our photometry is calibrated using PanSTARRS and is not corrected for Galactic extinction.