Abstract
In addition to the next generation of beam-based neutrino experiments and their associated detectors, a number of intense, low-energy neutrino production sources from decays at rest will be in operation. In this work, we explore the physics opportunities with decay-at-rest neutrinos for complementary measurements of oscillation parameters at long baselines. The J-PARC Spallation Neutron Source, for example, will generate neutrinos from a variety of decay-at-rest (DAR) processes, specifically those of pions, muons, and kaons. Other proposed sources will produce large numbers of stopped pions and muons. We demonstrate the ability of the upcoming Hyper-Kamiokande experiment to detect the monochromatic kaon decay-at-rest neutrinos from J-PARC after they have traveled several hundred kilometers and undergone oscillations. This measurement will serve as a valuable cross-check in constraining our understanding of neutrino oscillations in a new regime of neutrino energy and baseline length. We also study the expected event rates from pion and muon DAR neutrinos in liquid argon and water detectors and their sensitivities to the charge-parity- ($CP$) violating phase ${\ensuremath{\delta}}_{\mathit{CP}}$.
Highlights
The discovery that neutrinos oscillate, and have mass, has revolutionized our understanding of the lepton sector of the standard model of particle physics
When treating neutrino oscillations in vacuum, a given oscillation probability is determined by the ratio of the distance traveled by the neutrino to its energy
We present a potential capability within oscillations from the threemassive-neutrinos paradigm: neutrinos from kaon-decayat-rest produced in the J-PARC Spallation Neutron Source (JSNS) [12] traveling several hundred kilometers to HyperKamiokande (HK) and interacting in a water Cherenkov detector [2]
Summary
The discovery that neutrinos oscillate, and have mass, has revolutionized our understanding of the lepton sector of the standard model of particle physics. Under the three-massive-neutrinos paradigm, we may calculate the oscillation probability of a πDAR or KDAR neutrino that is emitted as a νμ and travels a distance L These are too low energy to produce charged τ leptons, and we focus on the oscillation probabilities Pðνμ → νμÞ and Pðνμ → νeÞ. If the πDAR oscillation probability could be measured at L ≈ Oð100 kmÞ, perhaps using a different target than water, such a measurement would be sensitive to many effects of the three-massive-neutrinos formalism At these distances, as evident, the πDAR neutrino oscillation probability is driven by two frequencies (and their interference)—the atmospheric and solar-masssquared splittings are both relevant for these energies and distances. No parameter will be measured more precisely than next-generation (or current, for that matter) experimental constraints; this provides a consistency check on our understanding of the three-massive-neutrinos paradigm at a previously unexplored combination of baseline length and neutrino energy
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
