Dependence of radar backscatter on the energetics of the air-sea interface

The Normalized Radar Cross-Section (NRCS), the fundamental measurement made by radar scatterometers, was obtained as part of the Water-Air Vertical Exchanges 1987 (WAVES87) experiment. The experiment was designed to evaluate the effects of environmental parameters on the NRCS and was performed from a research tower located in Lake Ontario, on which two microwave scatterometers operating at 14.0 and5.0 GHz were installed for six weeks in the autumn of 1987. The novel aspect of this experiment was that the 14.0 GHz radar automatically rotated through 300 degrees in azimuth angle at six different incidence angles to the water surface, accompanied by simultaneous measurements of wind stress and high resolution directional wave spectra. Therefore, the incident and azimuthal angle behavior of the NRCS was examined as a function of wind speed, friction velocity, wind direction, and atmospheric stability. The dependence of the NRCS on wind speed for various incidence angles is similar to previous results. However, the slope exponents of the NRCS vs. 19.5 wind speed curves at intermediate incidence angles are higher than the corresponding open ocean measurements. Scaling the lake neutral wind speed data by the ratio of lake to ocean drag coefficients reduces the slope of the curves and suggests the drag coefficient has a sea state dependence. The correlation between NRCS and neutral wind speed at 1 m is higher (0.91)than between the NRCS and friction velocity (.073 at 40 degrees). The minima in the sinusoidal modulation of the NRCS as a function of relative wind angle (the angle between the wind and antenna directions) are often shifted (by as much as 45 degrees) such that the minima do not always occur at cross-wind angles. Instead, the angular distance between the NRCS minima in the case of a wind-wave sea appears to approximate the directional spread of the waves about the upwind direction, generally less than 180 degrees. The degree of the sinusoidal modulation of the NRCS with relative wind angle is highly correlated with significant slope and inverse wave age at 20 degree incidence angle (0.90) and moderately correlated at 40 degrees (0.75); i.e., increased azimuthal modulation at 20 degrees is associated with a steeper wave field. The dependence of the NRCS on atmospheric stability shows the NRCS to decrease by about 5 dB between air-water temperature difference of -16 and +10 degrees centigrade. This stability effect is removed by parameterization of the NRCS in terms of either the friction velocity or neutral wind speed at 1m, with the neutral wind speed providing the best normalization of the data. The result show that radar scatterometers are an especially sensitive means by which to study the air-sea interface; the magnitudes of the 5.- GHz and 14 GHz NRCS respond nearly instantaneously to changes in the near-surface neutral wind speed, but the directionality of the (Ku-band) NRCS is the result of complicated interrelationships among the influencing environmental variables.Approved for public release; distribution is unlimited.Civilian, United States Navyhttp://archive.org/details/dependenceofrada109452644

Hydrographic data from the OPTOMA Program: OPTOMA12, 8-18 October 1984, OPTOMA13, 22 October-3 November 1984, OPTOMA13P, 27 October 1984, OPTOMA14, 3-14 November 1984

The three cruises, OPTOMA12, OPTOMA13, and 0PT0MA14, and one AXBT flight, 0PT0MA13P, were under taken in October and November, 1984. This report presents the hydrographic data, acquired by XBT, AXBT and CTD casts, from the cruises and the flight."Ocean Prediction Through Observations, Modeling and Analysis" sponsored by the Physical Oceanography Program of the Office of Naval Research under Program Element 61153N.http://archive.org/details/hydrographicdata012wittN0001484NR24501NAApproved for public release; distribution is unlimited

Hydrographic data from the OPTOMA Program: OPTOMA11, 5-June-5 August, 1984

The six cruises and one aircraft flight comprising OPTOMA11 were undertaken in June, July and August 1984 to sample two subdomains of the California Current. This report presents the hydrographic data, acquired by XBT, AXBT and CTD casts, from the cruises and the flight.Research project "Ocean Prediction Through Observations, Modeling and Analysis" sponsored by the Physical Oceanography Program of the Office of Naval Research under Program Element 61153N.http://archive.org/details/hydrographicdata011wittN000148WR24051NAApproved for public release; distribution is unlimited

Low exposure long-baseline neutrino oscillation sensitivity of the DUNE experiment

The Deep Underground Neutrino Experiment (DUNE) will produce world-leading neutrino oscillation measurements over the lifetime of the experiment. In this work, we explore DUNE's sensitivity to observe charge-parity violation (CPV) in the neutrino sector, and to resolve the mass ordering, for exposures of up to 100 kiloton-megawatt-years (kt-MW-yr). The analysis includes detailed uncertainties on the flux prediction, the neutrino interaction model, and detector effects. We demonstrate that DUNE will be able to unambiguously resolve the neutrino mass ordering at a 3$\sigma$ (5$\sigma$) level, with a 66 (100) kt-MW-yr far detector exposure, and has the ability to make strong statements at significantly shorter exposures depending on the true value of other oscillation parameters. We also show that DUNE has the potential to make a robust measurement of CPV at a 3$\sigma$ level with a 100 kt-MW-yr exposure for the maximally CP-violating values \delta_{\rm CP}} = \pm\pi/2. Additionally, the dependence of DUNE's sensitivity on the exposure taken in neutrino-enhanced and antineutrino-enhanced running is discussed. An equal fraction of exposure taken in each beam mode is found to be close to optimal when considered over the entire space of interest

A Gaseous Argon-Based Near Detector to Enhance the Physics Capabilities of DUNE

This document presents the concept and physics case for a magnetized gaseous argon-based detector system (ND-GAr) for the Deep Underground Neutrino Experiment (DUNE) Near Detector. This detector system is required in order for DUNE to reach its full physics potential in the measurement of CP violation and in delivering precision measurements of oscillation parameters. In addition to its critical role in the long-baseline oscillation program, ND-GAr will extend the overall physics program of DUNE. The LBNF high-intensity proton beam will provide a large flux of neutrinos that is sampled by ND-GAr, enabling DUNE to discover new particles and search for new interactions and symmetries beyond those predicted in the Standard Model

Snowmass Neutrino Frontier: DUNE Physics Summary

The Deep Underground Neutrino Experiment (DUNE) is a next-generation long-baseline neutrino oscillation experiment with a primary physics goal of observing neutrino and antineutrino oscillation patterns to precisely measure the parameters governing long-baseline neutrino oscillation in a single experiment, and to test the three-flavor paradigm. DUNE's design has been developed by a large, international collaboration of scientists and engineers to have unique capability to measure neutrino oscillation as a function of energy in a broadband beam, to resolve degeneracy among oscillation parameters, and to control systematic uncertainty using the exquisite imaging capability of massive LArTPC far detector modules and an argon-based near detector. DUNE's neutrino oscillation measurements will unambiguously resolve the neutrino mass ordering and provide the sensitivity to discover CP violation in neutrinos for a wide range of possible values of δCP. DUNE is also uniquely sensitive to electron neutrinos from a galactic supernova burst, and to a broad range of physics beyond the Standard Model (BSM), including nucleon decays. DUNE is anticipated to begin collecting physics data with Phase I, an initial experiment configuration consisting of two far detector modules and a minimal suite of near detector components, with a 1.2 MW proton beam. To realize its extensive, world-leading physics potential requires the full scope of DUNE be completed in Phase II. The three Phase II upgrades are all necessary to achieve DUNE's physics goals: (1) addition of far detector modules three and four for a total FD fiducial mass of at least 40 kt, (2) upgrade of the proton beam power from 1.2 MW to 2.4 MW, and (3) replacement of the near detector's temporary muon spectrometer with a magnetized, high-pressure gaseous argon TPC and calorimeter

Snowmass Neutrino Frontier: DUNE Physics Summary

The Deep Underground Neutrino Experiment (DUNE) is a next-generation long-baseline neutrino oscillation experiment with a primary physics goal of observing neutrino and antineutrino oscillation patterns to precisely measure the parameters governing long-baseline neutrino oscillation in a single experiment, and to test the three-flavor paradigm. DUNE's design has been developed by a large, international collaboration of scientists and engineers to have unique capability to measure neutrino oscillation as a function of energy in a broadband beam, to resolve degeneracy among oscillation parameters, and to control systematic uncertainty using the exquisite imaging capability of massive LArTPC far detector modules and an argon-based near detector. DUNE's neutrino oscillation measurements will unambiguously resolve the neutrino mass ordering and provide the sensitivity to discover CP violation in neutrinos for a wide range of possible values of $\delta_{CP}$. DUNE is also uniquely sensitive to electron neutrinos from a galactic supernova burst, and to a broad range of physics beyond the Standard Model (BSM), including nucleon decays. DUNE is anticipated to begin collecting physics data with Phase I, an initial experiment configuration consisting of two far detector modules and a minimal suite of near detector components, with a 1.2 MW proton beam. To realize its extensive, world-leading physics potential requires the full scope of DUNE be completed in Phase II. The three Phase II upgrades are all necessary to achieve DUNE's physics goals: (1) addition of far detector modules three and four for a total FD fiducial mass of at least 40 kt, (2) upgrade of the proton beam power from 1.2 MW to 2.4 MW, and (3) replacement of the near detector's temporary muon spectrometer with a magnetized, high-pressure gaseous argon TPC and calorimeter.Comment: Contribution to Snowmass 202

Scintillation light detection in the 6-m drift-length ProtoDUNE Dual Phase liquid argon TPC

DUNE is a dual-site experiment for long-baseline neutrino oscillation studies, neutrino astrophysics and nucleon decay searches. ProtoDUNE Dual Phase (DP) is a 6 x 6 x 6 m3 liquid argon time-projection-chamber (LArTPC) that recorded cosmic-muon data at the CERN Neutrino Platform in 2019-2020 as a prototype of the DUNE Far Detector. Charged particles propagating through the LArTPC produce ionization and scintillation light. The scintillation light signal in these detectors can provide the trigger for non-beam events. In addition, it adds precise timing capabilities and improves the calorimetry measurements. In ProtoDUNE-DP, scintillation and electroluminescence light produced by cosmic muons in the LArTPC is collected by photomultiplier tubes placed up to 7m away from the ionizing track. In this paper, the ProtoDUNE-DP photon detection system performance is evaluated with a particular focus on the different wavelength shifters, such as PEN and TPB, and the use of Xe-doped LAr, considering its future use in giant LArTPCs. The scintillation light production and propagation processes are analyzed and a comparison of simulation to data is performed, improving understanding of the liquid argon properties

A Gaseous Argon-Based Near Detector to Enhance the Physics Capabilities of DUNE

This document presents the concept and physics case for a magnetized gaseous argon-based detector system (ND-GAr) for the Deep Underground Neutrino Experiment (DUNE) Near Detector. This detector system is required in order for DUNE to reach its full physics potential in the measurement of CP violation and in delivering precision measurements of oscillation parameters. In addition to its critical role in the long-baseline oscillation program, ND-GAr will extend the overall physics program of DUNE. The LBNF high-intensity proton beam will provide a large flux of neutrinos that is sampled by ND-GAr, enabling DUNE to discover new particles and search for new interactions and symmetries beyond those predicted in the Standard Model.Comment: Contribution to Snowmass 202

Reconstruction of interactions in the ProtoDUNE-SP detector with Pandora

The Pandora Software Development Kit and algorithm libraries provide pattern-recognition logic essential to the reconstruction of particle interactions in liquid argon time projection chamber detectors. Pandora is the primary event reconstruction software used at ProtoDUNE-SP, a prototype for the Deep Underground Neutrino Experiment far detector. ProtoDUNE-SP, located at CERN, is exposed to a charged-particle test beam. This paper gives an overview of the Pandora reconstruction algorithms and how they have been tailored for use at ProtoDUNE-SP. In complex events with numerous cosmic-ray and beam background particles, the simulated reconstruction and identification efficiency for triggered test-beam particles is above 80% for the majority of particle type and beam momentum combinations. Specifically, simulated 1 GeV/$c$ charged pions and protons are correctly reconstructed and identified with efficiencies of 86.1$\pm0.6$% and 84.1$\pm0.6$%, respectively. The efficiencies measured for test-beam data are shown to be within 5% of those predicted by the simulation.Comment: 39 pages, 19 figure