Neutrino fluxes from a high-intensity spallation neutron facility

Abstract

The neutrino production rates for a spallation neutron source with proton beams in the energy range 650 < T p < 2200 MeV are calculated to an estimated accuracy of 25%. The target geometries used are based on the tantalum and mercury targets proposed for the European Spallation Source. Results for ν μ , ν e, and ν μ rates due to π + and μ + decay at rest, and for ν μ rates from π + decay in flight, are presented in terms of neutrinos per proton. Production rates for decay at rest from a tantalum target are calculated to be ( ν p −1)=0.075 at T p=1000 MeV, and 0.327 at 2200 MeV. For a neutrino detector located 20 m from a tantalum target, and at 0° to a 1500 MeV proton beam, the integrated flux of ν μ above 150 MeV from π + decay in flight is 3.0 × 10 5 cm −2 s −1. Backgrounds of ν e , from the π − decay-in-flight and μ − decay-at-rest chain, vary from 0.05% to 0.09% of the ν e flux.