TITLE: GCN CIRCULAR NUMBER: 45510 SUBJECT: GRB 260903A: EP-FXT follow-up observation DATE: 26/09/04 06:11:05 GMT FROM: EP Team at NAOC/CAS <ep_ta@bao.ac.cn> R.-Z. Li (YNAO, CAS), Z.-M. Wang (BNU), R. Shi (PMO), H. Sun (NAO,CAS) on behalf of the Einstein Probe (EP) team: EP-FXT performed a follow-up observation of GRB 260903A, detected by SVOM/ECLAIRs (sb26090302; Brunet et al., GCN 45499), at 2026-09-03 14:46:48 (UTC), about 2.16 hours after the SVOM/ECLAIRs trigger, with an exposure time of 6005 s. On-ground analysis of the EP-FXT data found an uncataloged fading X-ray source within the SVOM/VT error region (Li et al., GCN 45504). The preliminary results for the X-ray source are as follows: Source name: EPF_J014238.7+112211 R.A., Decl. (J2000) = 25.6614, 11.3696 deg Localization error radius = 10 arcsec 0.5-10 keV flux = 9.76e-13 erg/cm^ 2/s Flux error = 1.94e-13 erg/cm^2/s (1 sigma) Launched on January 9, 2024, EP is a space X-ray observatory to monitor the soft X-ray sky with X-ray follow-up capability (Yuan et al. 2022, Handbook of X-ray and Gamma-ray Astrophysics). View this GCN Circular online at https://gcn.nasa.gov/circulars/45510. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...