A D₂O detector for flux normalization of a pion decay-at-rest neutrino source

Abstract

We report on the technical design and expected performance of a 592 kg heavy-water-Cherenkov detector to measure the absolute neutrino flux from the pion-decay-at-rest neutrino source at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL). The detector will be located roughly 20 m from the SNS target and will measure the neutrino flux with better than 5 % statistical uncertainty in 2 years. This heavy-water detector will serve as the first module of a two-module detector system to ultimately measure the neutrino flux to 2-3 % at both the First Target Station and the planned Second Target Station of the SNS. This detector will significantly reduce a dominant systematic uncertainty for neutrino cross-section measurements at the SNS, increasing the sensitivity of searches for new physics.

The COHERENT Experimental Program

“…6 shows that this is a sub-percent effect at PPU energies; to a very good approximation, the neutrino source will simply increase in intensity for the PPU upgrade. To ensure control of systematics and backgrounds during the PPU staging process, it will be important for the COHERENT experiment to monitor both the neutrino flux [6] and the neutron background [13] in Neutrino Alley at as many energy steps as possible.…”

“…• The COHERENT collaboration has additional existing and planned near-future deployments in Neutrino Alley at the SNS with exciting physics potential. Deployments already underway include 18 kg of Ge and 2 tonnes of NaI, as well as a heavy-water detector for flux normalization [6]. The experimental program under development includes tonne-scale argon, cryogenic inorganic scintillator and a liquid argon time-projection chamber.…”

Theoretical tools for neutrino scattering: interplay between lattice QCD, EFTs, nuclear physics, phenomenology, and neutrino event generators

“…This WP was informed by the many LOIs received in the first stage of the Snowmass community planning exercise and by the participants to the Snowmass workshops Mini-Workshop on Neutrino Theory (Sept 21-23, 2020), and Mini-workshop in preparation for the white paper "Theoretical tools for neutrino scattering: the interplay between lattice QCD, EFTs, nuclear physics, phenomenology, and neutrino event generators" (Aug [23][24][25]2021). This is a cross-frontier white paper solicited by the following Snowmass topical groups: TF05 (Lattice gauge theory); TF11/NF08 (Neutrino theory); and NF06 (Neutrino interaction cross sections).…”

“…The interaction rates of CEνNS are sensitive to neutron distributions in the nuclear targets (neutron nuclear structure factors), which dominate the theoretical uncertainties [18][19][20]. As CEνNS experiments continue to improve their experimental precision [21][22][23][24][25], more precise theory calculations of these structure factors are needed. In the same way as the proton responses are derived from electron scattering data, such precision calculations require data input, with CEνNS the most promising source probing the neutron distribution besides parity-violating electron scattering.…”

Radiative (anti)neutrino energy spectra from muon, pion, and kaon decays

“…While uncertainties on the electron antineutrino fluxes could be reduced from 10 % to a few-% level relying on the well-known inverse beta decay reaction at low energies [100][101][102][103][104][105], the muon component has no feasible "standard candles". However, the precise theoretical knowledge of muon and pion decays could allow us to control the muon over electron flavor ratios of incoming (anti)neutrinos.…”