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

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 Publication date 2006
  fields Physics
and research's language is English




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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 $70pm8$ (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.



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