TITLE: GCN CIRCULAR NUMBER: 16840 SUBJECT: Swift Trigger 613516 is not an astrophysical event DATE: 14/09/24 01:47:19 GMT FROM: David Palmer at LANL M. M. Chester (PSU) and D. M. Palmer (LANL) report on behalf of the Swift Team: At 01:39:55 UT, a temporary loss of star tracker lock caused the misidentification of Vela X-1 as an unknown source (trigger 613516). This event is not astrophysically significant.