The ATLAS detector viewed from the direction of the beam is circular, allowing us to sweep around it in a clockwise direction, looking for tracks and energy deposited in clusters. This is a bit like radar.

The detector is divided up into very thin wedges and a note is played if there is a track or cluster within the wedge. The pitch is determined by how much transverse momentum (for tracks) or energy (for clusters) is deposited in each wedge.

The resulting pieces are sweep_tthtracks  and sweep_tthclusters , named because the event being sonified is a 'ttH' event, which means that it is a simulated event containing two top quarks and a Higgs boson.