TITLE:   GCN CIRCULAR
NUMBER:  43541
SUBJECT: EP260126a: Seimei/TriCCS optical upper limit
DATE:    26/01/28 14:52:16 GMT
FROM:    Kenta Taguchi <kentagch@kusastro.kyoto-u.ac.jp>

Kenta Taguchi (Kyoto University) reports on behalf of a larger collaboration:

We observed the field of EP260126a detected by the Einstein Probe (Fu et al., GCN 43520) using the Tricolor CMOS Camera and Spectrograph (TriCCS) on the 3.8-m Seimei Telescope at the Okayama Observatory of Kyoto University.
Our observation started at 13:30:04 UT on 2026-01-26 (MJD = 61066.5625).
For each band, we took 30-second exposures 62 times (i.e., the total exposure time is 1860 s = 31 min).
From our preliminary analysis, the 5-sigma limiting magnitudes are 21.74, 21.36, and 21.33 AB mag for g, r, and i-band, respectively.
We detected no transient sources in the FXT error circle.