GCN Circular 45048

R. A. J. Eyles-Ferris (Leicester), D. B. Malesani (DAWN/NBI and Radboud), J. Sanchez-Sierras (Radboud), G. Corcoran (UCD), A. Martin-Carrillo (UCD), P. G. Jonker (Radboud), report on behalf of a larger collaboration:

We observed the field of the Einstein Probe fast X-ray transient EP260626a (Chen et al., GCN 45047

) with the 2m Liverpool Telescope on La Palma using the IO:O instrument. We obtained 6x150 s exposures in each of the SDSS r’ and z’ filters starting at 2026-06-27 02:24:23 UT, approximately 21 hours after the X-ray detection.

We performed image subtraction on the stacked images using reference images from Pan-STARRS and also compared the stacked and reference images manually. Within the EP/WXT localisation, we detect no new sources in any of the bands.

We derive the following 3-sigma upper limits for our stacked images. Our photometry is calibrated to PanSTARRS and not corrected for Galactic extinction.

t_mid (hours)	Filter	AB magnitude
21.13	r’	>22.89
21.44	z’	>22.37