Caption: Time distribution within the beam trigger window of all subevents with >200 PMT hits in the inner tank region and <6 PMT hits in the veto region. The beam spill occurs between ~4500ns and ~6500ns. Non-beam backgrounds are less than 0.001 of the beam induced events. The small pile-up at the beginning of the window is due to background events that occurred just before the trigger window but still produced PMT hits within the trigger window.