A Neutron Multiplicity Meter for Deep Underground Muon-Induced High Energy Neutron Measurements

Abstract

We present the design of an instrument capable of measuring the high energy ($>$60 MeV) muon-induced neutron flux deep underground. The instrument is based on applying the Gd-loaded liquid-scintillator technique to measure the rate of high-energy neutrons underground based on the neutron multiplicity induced in a Pb target. We present design studies based on Monte Carlo simulations that show that an apparatus consisting of a Pb target of 200 cm by 200 cm area by 60 cm thickness covered by a 60 cm thick Gd-loaded liquid scintillator (0.5% Gd content) detector could measure, at a depth of 2000 meters of water equivalent, a rate of $70\pm 8$ (stat) events/year. Based on these studies, we also discuss the benefits of using a neutron multiplicity meter as a component of active shielding in such experiments.

22 pages including 10 figures; corrected typos, extended references and improved description; revised version accepted for publication in NIM

References in corpus (1)

• The physics models of FLUKA: status and recent development

Cited by in corpus (2)

• Measurements of neutrons produced by high-energy muons at the Boulby Underground Laboratory
• Direct WIMP identification: Physics performance of a segmented noble-liquid target immersed in a Gd-doped water veto