TITLE: GCN CIRCULAR NUMBER: 41199 SUBJECT: GRB 250727A: EP-FXT follow-up observation DATE: 25/07/30 06:15:15 GMT FROM: EP Team at NAOC/CAS ep_ta@bao.ac.cn
Y.-H. I. Yin (NJU), R. D. Liang, W. Yuan (NAO, CAS) on behalf of the Einstein Probe (EP) team:
EP-FXT performed a follow-up observation of the SVOM/ECLAIRs-detected burst GRB 250727A (SVOM/sb25072701) (Cao et al. GCN 41176) at 2025-07-29T10:57:54 (UTC), about 48 hours after the SVOM/ECLAIRs trigger, with an exposure time of 3878s. Three FXT candidate sources (Yin et al. GCN 41182) are not detected in this observation. The upper limits are listed as follows.
Source 1: EPF_J234436.3-810410 RA (J2000): 356.1514 Dec (J2000): -81.0694 Flux upper limit: 8.78 x 10^-14 erg/s/cm2 (0.5-10 keV)
Source 2: EPF_J234357.8-811244 RA (J2000): 355.9909 Dec (J2000): -81.2121 Flux upper limit: 1.03 x 10^-13 erg/s/cm2 (0.5-10 keV)
Source 3: EPF_J234541.4-811245 RA (J2000): 356.4225 Dec (J2000): -81.2124 Flux upper limit: 6.40 x 10^-14 erg/s/cm2 (0.5-10 keV) Note: This source is spatially consistent with the candidate counterpart Source 1 (SWIFT J234539.1-811248) detected by Swift/XRT.
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/41199. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...