The physics impact of proton track identification in future megaton-scale water Cherenkov detectors

Abstract

E-mail: maximilien.fechner@cea.fr, chris.walter@duke.edu Abstract: In this paper, we investigate the impact in future megaton-scale water Cherenkov detectors of identifying proton Cherenkov rings. We estimate the expected event rates for detected neutral current and charged current quasi-elastic neutrino interactions from atmospheric neutrinos in a megaton-scale Super-Kamiokande-like detector with both 40% and 20% photo-cathode coverage. With this sample we examine the prospects for measuring the neutrino oscillation pattern, and searching for sterile neutrinos. We also determine the size of selected charged current quasi-elastic samples in a 300-kton fiducial volume Super-Kamiokande-like detector from examples of both conventional super-beams and beta-beams proposed in the literature. With these samples, it is shown that full kinematic neutrino reconstruction using the outgoing proton can improve the reconstructed energy resolution, and give good neutrino versus anti-neutrino tagging capabilities, adding important capabilities to water Cherenkov detectors in future projects. We determine the beam parameters necessary to make use of this technique and present distributions of neutrino and anti-neutrino selection efficiencies.

(In)direct detection of boosted dark matter

“…(2.5). When the transferred energy is above 2.5 GeV, the elastic scattering cross section is rather small, and protons instead typically produce secondary hadronic showers [67]. In that case, one should transition to the DIS calculation below.…”

“…For elastic scattering, this logic favors electrons over protons in two different ways: an O(1 GeV) ψB can more effectively transfer momentum to electrons compared to protons because of the heavier proton mass, and protons require a larger absolute momentum transfer to get above the Cherenkov threshold. Compounding these issues, protons have an additional form-factor suppression, identifying proton tracks is more challenging than identifying electron tracks[66][67][68], and the angular resolution for protons is worse than for electrons at these low energies[68]. We note that liquid Argon detectors are able to reconstruct hadronic final states using ionization instead of Cherenkov light, so they may be able to explore the (quasi-)elastic proton channels down to lower energies, even with smaller detector volumes[12,13].…”

Measurement of the neutrino component of an antineutrino beam observed by a nonmagnetized detector

“…Fitting the lifetime distributions or measuring how often a decay electron is produced could supply constraints that are especially useful as they are independent of the underlying neutrino interaction cross sections. Also, selection of CCQE interactions with and without a proton in the final state may afford additional neutrino versus anti-neutrino tagging capabilities [51,52].…”

DUNE atmospheric neutrinos: Earth tomography

“…Proton direction has been used above Cherenkov threshold to aide in directional measurements of high-energy atmospheric neutrinos at Super-Kamiokande (see, e.g., refs [116][117][118]…”