Speaker
Description
Cosmogenic muons are a major background source in rare event search experiments. To mitigate this background, neutrinoless double beta decay (0νββ) and direct detection dark matter experiments prefer to operate in deep underground laboratories, where they can receive adequate shielding from cosmic rays. However, high energy muons can still reach underground and create backgrounds for these experiments. To reduce such cosmogenic muon backgrounds, the rare-event search experiments deploy an outer detector to tag the muons. These outer detectors serve both as shielding and as active muon veto systems.An active muon veto detects light produced either by Cherenkov radiation (when the detector is filled with water) or by scintillation (when filled with a scintillating medium). The outer detector is equipped with photon detection modules, such as photomultiplier tubes (PMTs) or silicon photomultipliers (SiPMs), to capture these light signals. Additionally, the outer detector offers passive shielding by moderating secondary neutrons generated from muon interactions. In this talk, I will discuss the requirements for deep underground laboratories and the specifications of outer detectors for both current and next-generation rare-event search experiments.