TITLE:   GCN CIRCULAR
NUMBER:  45668
SUBJECT: EP260920b: LCO optical counterpart detection
DATE:    26/09/21 02:13:34 GMT
FROM:    liuxing@nao.cas.cn


X. Liu, D. Xu, J. An, Z. Fan, J.F. Gou, L.B. He, S.Q. Jiang, W.X. Li, R.D. Liang, Q. Zhao, Z.P. Zhu (NAOC), S.Y. Fu, L. Lei (HUST), Y.L. Hua (PMO) report:

We observed the field of EP260920b detected by EP (Ni et al., GCN 45664), using an LCO 1m telescope network. We obtained 3*200s exposures in the SDSS r' filter.

An uncatalogued and decaying source is detected within the EP-FXT error circle (Ni et al., GCN 45664) at coordinates

R.A. (J2000) = 21:42:20.79
Dec. (J2000) = -28:02:24.4

with an uncertainty of ~ 0.5 arcsec. The source had r = 18.97 +/- 0.04 mag at a median time of 0.68 hr post-trigger, calibrated with Pan-STARRS DR2 and not corrected for Galactic extinction.

We thus think the source is the optical counterpart of EP260920b.