TITLE: GCN CIRCULAR NUMBER: 44810 SUBJECT: EP260602a: Liverpool Telescope optical upper limits DATE: 26/06/03 19:58:47 GMT FROM: A. Bochenek at Liverpool John Moores University <a.m.bochenek@2023.ljmu.ac.uk> A. Bochenek, D. A. Perley, J. L. Wise (LJMU), report: We observed the field of EP260602a (Li et al., GCN 44770) using the IO:O optical camera on the 2m robotic Liverpool Telescope. We obtained multiple 150s exposures in SDSS gri filters, starting at 2026-06-02 21:15:26 UT, approximately 13.07 hours after trigger. The observations were interrupted and consequently resumed due to weather conditions and telescope tracking issues; some exposures needed to be discarded. We do not detect any sources at the position of the counterpart (Xu et al., GCN 44781, Li et al., GCN 44794; also Watson et al., GCN 44790; He et al., GCN 44798, Malesani et al., GCN 44807) down to the 3 sigma limiting magnitudes of: | MJD (mid) | T_mid-T_0 | Exp. Time | Filter | Mag limit. (AB) | | ------------ | ------------ | ------------ | ------------ | --------------- | | 61193.93925 | 14.34 h | 600 s | g | > 21.8 | | 61193.91413 | 13.75 h | 960 s | r | > 22.1 | | 61194.11373 | 18.54 h | 720 s | i | > 21.9 | The stacked exposures were subtracted from PanSTARRS reference imaging using custom PSF-matching image subtraction code utilising Swarp, SourceExtractor, and PSFex. The photometry is in the AB magnitude system, was calibrated using nearby PanSTARRS secondary standards and was not corrected for extinction. View this GCN Circular online at https://gcn.nasa.gov/circulars/44810. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...