GCN 43496: EP260119a: Xinglong optical upper limit

2026-01-22T03:29:52.667Z | rev 2 | event: GRB 260119A

Junjie-Jin (NAOC), Haiyang-Mu (NAOC), Sen-Liu (NAOC), Pengliang-Du (NAOC),
Zhou-Fan (NAOC), Hong-Wu (NAOC) report:
Following the detection of EP260119a by EP-WXT (GCN Circular 43447,GCN Circular 43452), we observed the field of EP260119a using the 2.16-m
telescope at Xinglong Observatory, NAOC. We obtained 600s clear-band frames with a
median time of 2026-01-19 18:38:00 hr after the EP trigger.
No uncatalogued optical transient is detected in the stacked images within the 3 arcmin
EP/WXT error circle (GCN Circular 43447), down to 5-sigma limiting magnitudes of z ~
19.8(not good day with thin cloud and bad seeing), calibrated with Pan-STARRS sources in the field. Also there is no apparent brightening for the catalogued sources within the error circle. Based on the location of the report(GCN Circular 43452), the target was not observed.