TITLE: GCN CIRCULAR NUMBER: 41224 SUBJECT: EP250802a: Liverpool Telescope optical upper limits DATE: 25/08/04 01:27:27 GMT FROM: A. Bochenek at Liverpool John Moores University a.m.bochenek@2023.ljmu.ac.uk

A. Bochenek and D. A. Perley (LJMU) report:

We observed the field of the fast X-ray transient EP250802a (Yin et al., GCN 41221) using the IO:O optical camera on the 2m robotic Liverpool Telescope. We obtained 4x120s exposures in the SDSS r’ and i’ filters starting at 2025-08-03 21:42:37 UT, approximately 35 hours after the trigger.

The images were stacked, and their background was subtracted relative to Pan-STARRS-1 using PSF matching with the help of PSFEx. We do not detect any new object at the EP/WXT error region of the transient: the 3-sigma limiting magnitudes on the stacked images are r > 22.67 mag and i > 22.33 mag, in line with Mohan et al. (GCN 41222) and Lipunov et al. (GCN 41223). However, we note that there are a few bright, saturated stars inside the error region on our images, impacting the image subtraction.

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