TITLE: GCN CIRCULAR NUMBER: 41227 SUBJECT: EP250802a: additional Liverpool Telescope upper limits DATE: 25/08/04 12:15:11 GMT FROM: Rob Eyles-Ferris at U of Leicester raje1@leicester.ac.uk

R. A. J. Eyles-Ferris and N. R. Tanvir (U of Leicester) report on behalf of a larger collaboration:

We observed the field of the X-ray transient EP250802a (Yin et al., GCN 41221) with the 2m Liverpool Telescope using the IO:O instrument. We obtained 8x150s exposures in each of the SDSS r’ and SDSS z’ filters starting at 2025-08-03 22:17:48 UT, approximately 35.7 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. Similarly to Bochanek et al. (GCN 41224), the bright stars in the error region affected our subtractions, however, no new sources are detected in either the subtractions or stacked images. Our results are consistent with Mohan et al. (GCN 41222), Lipunov et al. (GCN 41223) and Bochanek et al. (GCN 41224).

At the position of the X-ray source, we derive 3-sigma upper limits of r’ > 22.44 and z’ > 21.73 with photometry calibrated to Pan-STARRS and not corrected for Galactic extinction.

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