A search for the decays of stopped long-lived particles with ATLAS

A search for long-lived particles, which have come to rest within the ATLAS detector, is presented. The subsequent decays of these long-lived particles can produce high-momentum jets, resulting in large out-of-time energy deposits in the ATLAS calorimeters. These decays are detected using data collected during periods when collisions are absent in the bunch structure of the Large Hadron Collider. The analysed dataset is composed of events from proton--proton collisions produced by the LHC at a centre-of-mass energy of $\sqrt{s}=13~$TeV and recorded by the ATLAS experiment during 2017 and 2018.