{
  "subject": "EP250109a: Swift/XRT non-detection",
  "createdOn": 1736424778151,
  "format": "text/plain",
  "submittedHow": "web",
  "body": "J. A. Kennea (PSU) and P. A. Evans (Leicester) on behalf of the Swift XRT Team report:\n\nOn 09:19:41UT Swift XRT began a 950s exposure of the field containing the recently reported transient EP250109a (GCN #38864), 3 hours after detection by Einstein Probe WXT. Examination of the XRT data does not reveal any new X-ray sources, with an upper limit on count rate of 0.01 c/s at the EP FXT position. For a typical GRB-like spectrum this equates to an upper limit on flux of 3 x 10^-13 erg/s/cm^2 (0.3-10 keV). \n\nAlthough GCN #38864 does not report flux, the Swift/XRT non-detection suggests that this transient has rapidly faded. ",
  "circularId": 38867,
  "eventId": "EP250109a",
  "bibcode": "2025GCN.38867....1K",
  "submitter": "Jamie Kennea at Penn State <jak51@psu.edu>"
}