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This report has been prepared as part of the US Community Study on the Future of Particle Physics (Snowmass 2021) by the Snowmass Neutrino Frontier Topical Group NF07 Conveners, based on input from contributed White papers and Letters of Interest., Submitted to the Proceedings of the US Community Study on the Future of Particle Physics (Snowmass 2021); Topical Group Report for NF07 (Neutrino Frontier Topical Group on Applications)

Journal of the Physical Society of Japan 91(9), 091004 (2022). doi:10.7566/JPSJ.91.091004, The microscopic structure of two new infrared-driven amorphous white light generators, namely [(PhSn)$_4$S$_6$] and [(CpSn)$_4$S$_6$] and a related amorphous material [(NpSn)$_4$S$_6$], showing 2nd harmonics generation instead, were explored by X-ray and neutron diffraction, EXAFS and Reverse Monte Carlo simulations to explore relations between their extreme nonlinear optical behavior and microscopic structural properties. The current state of research is reported and experimental and simulation results are discussed. The prominent observation is that the molecular units are distorted in the WLG materials which seems not to be the case for the 2nd harmonics generator. Associated is the formation of a net of similarly spaced intra- and intermolecular sulfur atoms which is interpreted as a vibrational network that could explain the high receptivity of the material for infrared radiation. It is also found that the molecules arrange in chains with staggered configuration regarding the arrangement of the organic ligands., Published by The Physical Society of Japan, Tokyo

We present results of several measurements of CsI[Na] scintillation response to 3-60 keV energy nuclear recoils performed by the COHERENT collaboration using tagged neutron elastic scattering experiments and an endpoint technique. Earlier results, used to estimate the coherent elastic neutrino-nucleus scattering (CEvNS) event rate for the first observation of this process achieved by COHERENT at the Spallation Neutron Source (SNS), have been reassessed. We discuss corrections for the identified systematic effects and update the respective uncertainty values. The impact of updated results on future precision tests of CEvNS is estimated. We scrutinize potential systematic effects that could affect each measurement. In particular we confirm the response of the H11934-200 Hamamatsu photomultiplier tube (PMT) used for the measurements presented in this study to be linear in the relevant signal scale region., Comment: The version accepted by JINST. The changes made as a result of the peer review process: 1. Section 8 "Global CsI[Na] QF data fit" is expanded. The main fit result and its uncertainty is NOT CHANGED. An alternative fit is now shown in Figure 14, Figure 15 is added to further validate the assumptions in the main fit. 2. The Appendix B is restructured for clarity

MicroCHANDLER is a prototype detector for surface-level reactor antineutrino detection made with plastic scintillator cubes (EJ-260). We measured the proton quenching effect in the scintillator with neutron beams of 5-27 MeV at the Triangle Universities Nuclear Laboratory (TUNL). We extracted the Birks' constants from our data. This result improves the energy non-linearity modeling of plastic scintillator detectors in an unprecedented energy range. In addition, the updated energy response function for recoil protons will lead to an improved modeling of fast neutrons, which is needed to optimize the shielding design.

This article reports an improved independent measurement of neutrino mixing angle θ_(13) at the Daya Bay Reactor Neutrino Experiment. Electron antineutrinos were identified by inverse β-decays with the emitted neutron captured by hydrogen, yielding a data set with principally distinct uncertainties from that with neutrons captured by gadolinium. With the final two of eight antineutrino detectors installed, this study used 621 days of data including the previously reported 217-day data set with six detectors. The dominant statistical uncertainty was reduced by 49%. Intensive studies of the cosmogenic muon-induced ^9Li and fast neutron backgrounds and the neutron-capture energy selection efficiency, resulted in a reduction of the systematic uncertainty by 26%. The deficit in the detected number of antineutrinos at the far detectors relative to the expected number based on the near detectors yielded sin^22θ_(13) =0.071±0.011in the three-neutrino-oscillation framework. The combination of this result with the gadolinium-capture result is also reported.

This is the final report of DOE Grant DE-FG05-92ER40709 awarded to the Virginia Tech high energy physics group. It covers the period February 1, 2010 through April 30, 2013. The high energy physics program at Virginia Tech supported by this grant is organized into three tasks: A for theory (Profs. Tatsu Takeuchi and Djordje Minic), B for heavy flavor physics with the Belle and Belle II experiments (Prof. Leo Piilonen), and N for neutrino physics (Profs. Jonathan Link and Piilonen).

First results on inclusive D-0 and D-*+/- production in neutral current deep inelastic ep scattering are reported using data collected by the H1 experiment at HERA in 1994. Differential cross sections are presented for both channels and are found to agree well with QCD predictions based on the boson gluon fusion process. A charm production cross section for 10 GeV2 less than or equal to Q(2) less than or equal to 100 GeV2 and 0.01 less than or equal to y less than or equal to 0.7 of sigma (ep --> ) = (17.4 +/- 1.6 +/- 1.7 +/- 1.4) nb is derived. A first measurement of the charm contribution F(2)() (x, Q(2)) to the proton structure function for Bjorken x between 8 . 10(-4) and 8 . 10(-3) is presented. In this kinematic range a ratio F(2)()/F-2 = 0.237 +/- 0.021 +/- 0.041 is observed.

Particle physics aims to understand the universe around us. The Standard Model of particle physics describes the basic structure of matter and forces, to the extent we have been able to probe thus far. However, it leaves some big questions unanswered. Some are within the Standard Model itself, such as why there are so many fundamental particles and why they have different masses. In other cases, the Standard Model simply fails to explain some phenomena, such as the observed matter-antimatter asymmetry in the universe, the existence of dark matter and dark energy, and the mechanism that reconciles gravity with quantum mechanics. These gaps lead us to conclude that the universe must contain new and unexplored elements of Nature. Most of particle and nuclear physics is directed towards discovering and understanding these new laws of physics. These questions are best pursued with a variety of approaches, rather than with a single experiment or technique. Particle physics uses three basic approaches, often characterized as exploration along the cosmic, energy, and intensity frontiers. Each employs different tools and techniques, but they ultimately address the same fundamental questions. This allows a multi-pronged approach where attacking basic questions from different angles furthers knowledge and providesmore » deeper answers, so that the whole is more than a sum of the parts. A coherent picture or underlying theoretical model can more easily emerge, to be proven correct or not. The intensity frontier explores fundamental physics with intense sources and ultra-sensitive, sometimes massive detectors. It encompasses searches for extremely rare processes and for tiny deviations from Standard Model expectations. Intensity frontier experiments use precision measurements to probe quantum effects. They typically investigate very large energy scales, even higher than the kinematic reach of high energy particle accelerators. The science addresses basic questions, such as: Are there new sources of CP violation? Is there CP violation in the leptonic sector? Are neutrinos their own antiparticles? Do the forces unify? Is there a weakly coupled hidden sector that is related to dark matter? Do new symmetries exist at very high energy scales? To identify the most compelling science opportunities in this area, the workshop Fundamental Physics at the Intensity Frontier was held in December 2011, sponsored by the Office of High Energy Physics in the US Department of Energy Office of Science. Participants investigated the most promising experiments to exploit these opportunities and described the knowledge that can be gained from such a program. The workshop generated much interest in the community, as witnessed by the large and energetic participation by a broad spectrum of scientists. This document chronicles the activities of the workshop, with contributions by more than 450 authors. The workshop organized the intensity frontier science program along six topics that formed the basis for working groups: experiments that probe (i) heavy quarks, (ii) charged leptons, (iii) neutrinos, (iv) proton decay, (v) light, weakly interacting particles, and (vi) nucleons, nuclei, and atoms. The conveners for each working group included an experimenter and a theorist working in the field and an observer from the community at large. The working groups began their efforts well in advance of the workshop, holding regular meetings and soliciting written contributions. Specific avenues of exploration were identified by each working group. Experiments that study rare strange, charm, and bottom meson decays provide a broad program of measurements that are sensitive to new interactions. Charged leptons, particularly muons and taus, provide a precise probe for new physics because the Standard Model predictions for their properties are very accurate. Research at the intensity frontier can reveal CP violation in the lepton sector, and elucidate whether neutrinos are their own antiparticles. A very weakly coupled hidden-sector that may comprise the dark matter in the universe could be discovered. The search for proton decay can probe the unification of the forces with unprecedented reach and test sacrosanct symmetries to very high scales. Detecting an electric dipole moment for the neutron, or neutral atoms, could establish a clear signal for new physics, while limits on such a measurement would place severe constraints on many new theories. This workshop marked the first instance where discussion of these diverse programs was held under one roof. As a result, it was realized that this broad effort has many connections; a large degree of synergy exists between the different areas and they address similar questions. Results from one area were found to be pertinent to experiments in another domain.« less

We report the preliminary measurement by the FOCUS Collaboration (E831 at Fermilab) of masses and widths of the L=1 charm mesons $D_2^{*0}$ and $D_2^{*+}$. The fit of the invariant mass distribution requires an additional term to account for a broad structure over background., three pages, one figure, requires ws-p10x7.cls. Contributed paper to DPF 2000, Columbus (Ohio), USA

Using high statistics samples of charged-current nu(mu) interactions, the MiniNooNE Collaboration reports a measurement of the single-charged-pion production to quasielastic cross section ratio on mineral oil (CH2), both with and without corrections for hadron reinteractions in the target nucleus. The result is provided as a function of neutrino energy in the range 0.4 GeV < E-nu < 2.4 GeV with 11% precision in the region of highest statistics. The results are consistent with previous measurements and the prediction from historical neutrino calculations., We wish to acknowledge the support of Fermilab, the National Science Foundation, and the Department of Energy in the construction, operation, and data analysis of the MiniBooNE experiment.

Sterile neutrino ($\nu_s$) conversion in meter scale baselines can be sensitively probed using mono-energetic, sub-MeV, flavor pure $\nu_e$'s from an artificial MCi source and the unique technology of the LENS low energy solar $\nu_e$ detector. Active-sterile {\em oscillations} can be directly observed in the granular LENS detector itself to critically test and extend results of short baseline accelerator and reactor experiments., Comment: Submitted to the proceedings of the XII International Workshop on Neutrino Telescopes, March 6-9, 2007, Venice

We present a summary of recent results on CP violation and mixing in the charm quark sector based on a high statistics sample collected by photoproduction experiment FOCUS (E831 at Fermilab). We have measured the difference in lifetimes for the $D^0$ decays: $D^0 \to K^-\pi^+$ and $D^0 \to K^-K^+$. This translates into a measurement of the $y_{CP}$ mixing parameter in the $\d0d0$ system, under the assumptions that $K^-K^+$ is an equal mixture of CP odd and CP even eigenstates, and CP violation is negligible in the neutral charm meson system. We verified the latter assumption by searching for a CP violating asymmetry in the Cabibbo suppressed decay modes $D^+ \to K^-K^+\pi^+$, $D^0 \to K^-K^+$ and $D^0 \to \pi^-\pi^+$. We show preliminary results on a measurement of the branching ratio $\Gamma(D^{*+}\to \pi^+ (K^+\pi^-))/\Gamma(D^{*+}\to \pi^+ (K^-\pi^+))$., Comment: 9 pages, 6 figures, requires espcrc2.sty. Presented by S.Bianco at CPConf2000, September 2000, Ferrara (Italy). In this revision, fixed several stylistic flaws, add two significant references, fixed a typo in Tab.3

We present a new measurement of the total photoproduction cross section performed with the H1 detector at HERA. For an average centre of mass energy of 200~GeV a value of $\sigma_{tot}^{\gamma{p}}= 165\pm2\pm11\mu$b has been obtained. A detailed analysis of the data in adequate kinematic regions enabled a decomposition of the total cross section in its elastic, single diffractive dissociation and remaining non-diffractive parts, based on safe assumptions on the double diffractive dissociation contribution., Comment: 20 pages, latex, 6 figures appended as uuencoded file

Properties of the hadronic final state in photoproduction events with large transverse energy are studied at the electron-proton collider HERA. Distributions of the transverse energy, jets and underlying event energy are compared to $\overline{p}p$ data and QCD calculations. The comparisons show that the $\gamma p$ events can be consistently described by QCD models including -- in addition to the primary hard scattering process -- interactions between the two beam remnants. The differential jet cross sections $d\sigma/dE_T^{jet}$ and $d\sigma/d\eta^{jet}$ are measured., Comment: 27 pages, latex, 7 figures appended as uuencoded file

The XENON1T experiment recently reported an excess of events at low electron recoil energies, which may be due to interactions of solar neutrinos inside the detector via a large neutrino magnetic moment. We point out that a $^{51}$Cr neutrino source placed close to the detector can directly test this hypothesis., Comment: 2 pages, 2 figures

This report summarizes the current status of neutrino physics and the broad and exciting future prospects identified for the Neutrino Frontier as part of the 2021 Snowmass Process., Comment: 49 pages, contribution to: 2021 Snowmass Summer Study. Minor updates