Neutron- and muon-induced background in underground physics experiments

TL;DR

This paper reviews neutron and muon-induced backgrounds in underground physics experiments, emphasizing the importance of Monte Carlo simulations for background estimation and experiment optimization.

Contribution

It provides a comprehensive review of Monte Carlo methods used to evaluate neutron backgrounds and discusses their reliability in underground experiments.

Findings

Monte Carlo simulations are essential for background estimation.

Reliability of Monte Carlo methods varies and is critically discussed.

Background sources include natural radioactivity and cosmic-ray interactions.

Abstract

Background induced by neutrons in deep underground laboratories is a critical issue for all experiments looking for rare events, such as dark matter interactions or neutrinoless 2-beta decay. Neutrons can be produced either by natural radioactivity, via spontaneous fission or (alpha,n) reactions, or by interactions initiated by high-energy cosmic rays. In all underground experiments, Monte Carlo simulations of neutron background play a crucial role for the evaluation of the total background rate and for the optimization of rejection strategies. The Monte Carlo methods that are commonly employed to evaluate neutron-induced background and to optimize the experimental setup, are reviewed and discussed. Focus is given to the issue of reliability of Monte Carlo background estimates.