Displaced tau jets: An exercise in unconventional signatures at the ATLAS experiment

• Alex Veltman (The University of Edinburgh)

Searches for new beyond the Standard Model (BSM) physics at the ATLAS experiment typically target particles that decay promptly, very close to the collision point. New physics has so far evaded these searches. Multiple BSM models predict new long-lived particles (LLPs) that are produced at the interaction point with decay lengths ranging from millimetres to kilometres. In new physics scenarios where LLPs couple preferentially to heavy particles or to leptons, tau lepton final states would offer high experimental sensitivity. Highly displaced tau decays can be reconstructed if the LLPs decay within the ATLAS inner tracking system, providing a unique probe for new physics. The methods used to search for this unconventional signature are discussed in contrast to typical collider physics analyses.