GCN 44025: EP260314a: Xinglong optical upper limit

2026-03-16T13:00:42.672Z | rev 0 | event: EP260314a

Junbo-Zhang (NAOC),  Junjie-Jin (NAOC), Haiyang-Mu (NAOC), Feng-Xiao (NAOC), Jie-Zheng(NAOC), Zhou-Fan (NAOC), Hong-Wu (NAOC) report on behalf of a large collaboration:

Following the detection of EP260314a by EP-WXT (Zhao et al., GCN 44010; Wu et al., GCN 44016), we observed the field of EP260314a using the 2.16-m telescope at Xinglong Observatory, NAOC. We obtained 3x600s clear-band frames with a median time of 2026-03-15 17:58:07 (UT), 19.11 hr after the EP trigger.

No uncatalogued optical transient is detected in the stacked images within the 3 arcmin EP/WXT error circle  (Zhao et al., GCN 44010; Wu et al., GCN 44016), down to 3-sigma limiting magnitudes of g ~21.5, calibrated with Pan-STARRS sources in the field. Also there is no apparent brightening for the catalogued sources within the error circle.