TITLE: GCN CIRCULAR NUMBER: 5835 SUBJECT: Swift-BAT trigger 239987 is not a GRB DATE: 06/11/22 09:23:47 GMT FROM: Scott Barthelmy at NASA/GSFC S. McBreen (MPE), S. D. Barthelmy (GSFC), A. P. Beardmore (U Leicester), D. N. Burrows (PSU), P. A. Evans (U Leicester), J. A. Kennea (PSU), W. B. Landsman (NASA/GSFC), V. Mangano (INAF-IASFPA), C. B. Markwardt (GSFC/UMD), K. L. Page (U Leicester), D. M. Palmer (LANL), S. B. Pandey (UCL-MSSL), P. Romano (Univ. Bicocca & INAF-OAB), T. Sakamoto (NASA/ORAU), M. Stamatikos (NASA/ORAU) and H. Ziaeepour (UCL-MSSL) report on behalf of the Swift Team: At 08:58:16 UT, the Swift Burst Alert Telescope (BAT) triggered on the count rate increase during entry into the SAA, and located a marginal-significance peak in the resulting image (trigger=239987). Swift slewed immediately to the derived location. The BAT light curve shows no significant burst activity overlying the particle background increase. The XRT began observing the field at 08:59:31 UT, 74 seconds after the BAT trigger. The XRT centroided on a cosmic ray in the image. The quicklook downlinked image shows no evidence for a source in 3s of data.