TITLE:   GCN CIRCULAR
NUMBER:  45445
SUBJECT: GRB 260807A: EP-FXT follow-up observations
DATE:    26/08/26 11:11:27 GMT
FROM:    SVOM_group <svomgroup@bao.ac.cn>

Ruizhi Li (YNAO), Chao Wu, Huali Li, Wenjin Xie, Donghua Zhao (NAOC), Hui Yang, Laurent Bouchet (IRAP) report:

We performed two EP/FXT observations of the possible faint GRB 260807A detected by SVOM/ECLAIRs (Xie et al., GCN 45308). The first EP/FXT observation started at 2026-08-07 12:51:33 UTC, approximately 1.85 hours post-trigger, with an exposure time of 5.8 ks. The second EP/FXT observation started at 2026-08-13 07:44:00 UTC, approximately 5.86 days post-trigger, with an exposure time of 4.3 ks.

We analyzed the data from the two EP/FXT observations. None of the X-ray sources within the SVOM/ECLAIRs error circle (Xie et al., GCN 45308) showed significant fading between the two EP/FXT observations, with 90% confidence upper limits on the flux of 2.85 x 10^-14 erg cm^-2 s^-1 and 3.67 x 10^-14 erg cm^-2 s^-1, respectively.

We conclude that no credible X-ray source within the SVOM/ECLAIRs error circle can be identified as the X-ray afterglow of the burst.