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At least 1,693 records · Page 94

Neutrino interaction measurements with the MicroBooNE and ArgoNeuT liquid argon time projection chambers

Abstract Precise modeling of neutrino interactions on argon is crucial for the success of future experiments such as the Deep Underground Neutrino Experiment (DUNE) and the Short-Baseline Neutrino (SBN) program, which will use liquid argon time projection chamber (LArTPC) technology. Argon is a large nucleus, and nuclear effects—both on the initial and final-state particles in the interaction—are expected to be large in neutrino–argon interactions. Therefore, measurements of neutrino scattering cross sections on argon will be of particular importance to future DUNE and SBN oscillation measurements. This article presents a review of neutrino–argon interaction measurements from the MicroBooNE and ArgoNeuT collaborations, using two LArTPC detectors that have collected data in the NuMI and Booster Neutrino Beams at Fermilab. Measurements are presented of charged-current muon neutrino scattering in the inclusive channel, the ‘0 $$\pi $$ π ’ channel (in which no pions but some number of protons may be produced), and single pion production (including production of both charged and neutral pions). Measurements of electron neutrino scattering are presented in the form of $$\nu _e+\bar{\nu }_e$$ ν e + ν ¯ e inclusive scattering cross sections.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Commercial Vehicle Electrification Evaluation Toolkit (CVEET)

The CVEET can identify and characterize charging and battery capacity challenges for class 3-8 commercial vehicle electrification, including battery electric and plug in hybrid vehicles for various trucks, vans and buses, over a wide range of vehicle operation. The tool can help build the understanding of the impact of commercial vehicle electrification on energy consumption, payload penalty, and GHG (i.e., CO2) emissions. The tool employs a quantitative approach to estimate electric vehicle energy consumption, characterize component performance and determine appropriate charging assumptions to conduct a comprehensive priority analysis of MD/HD vehicle electrification using public domain data.

Gao, Zhiming↗

Towards a Description of the Ground State Properties of LiHm Complexes and Reaction Energetics of Hydrogenation of Small Li Clusters using VQE-based Quantum Chemical Calculations

<span style="font-family: Roboto; font-size: 11pt;">This presentation describes the utilization of the variational quantum eigensolver (VQE) using a unitary coupled cluster with singles and doubles (UCCSD) ansatz to simulate a series of LiH</span><sub style="font-family: Roboto; font-size: 11pt;">n</sub><span style="font-family: Roboto; font-size: 11pt;"> molecules (n=1-3), including their singly charged ions. The performance is considered using a simulator by systematically increasing system size, providing data to compare against future VQE calculations. The predicted energy profiles are in semi-quantitative agreement with highly accurate CCSD/FCI methods.</span>

quantum computing↗

Measurement of muon antineutrino charged current - 0 meson scattering, using the NOvA Near Detector

Antineutrino interaction cross sections are, at present, poorly constrained, particularly regarding the role of multi-nucleon processes such as 2-particle 2-hole (2p2h) interactions. The associated crosssection systematic uncertainties represent a significant challenge for precision oscillation measurements, especially for the next generation of neutrino experiments such as DUNE. We present a new measurement of the muon antineutrino charged-current cross section without mesons in the final state, using the high-statistics data set of the NOvA Near Detector. The analysis employs a cut-based selection enhanced by machine learning techniques to isolate a high-purity sample dominated by quasielastic (QE) and 2p2h interactions. We present the cross section as a function of the kinetic energy and scattering angle of the outgoing muon. We also present measurements of more model-dependent kinematic variables such as the neutrino energy and momentum transfer, to better probe the underlying nuclear physics. The results are compared against various neutrino event generators to test the robustness of current interaction models.

Vockerodt, Kevin John [Ohio State U.; Queen Mary, ↗

Resonant Extraction and Extinction Measurement for the Mu2e Experiment

The Mu2e experiment, currently under construction at Fermilab, will search for coherent neutrinoless muon to electron conversion, extending the sensitivity of searches for charged lepton flavour violation by four orders of magnitude in 3-5 years of data-taking. This improved sensitivity is made possible by using a pulsed beam structure that is optimized for reducing prompt backgrounds when muons are stopped on an aluminium target. Producing a high-rate pulsed beam is achieved using resonant extraction of a circulating proton beam, an “AC dipole” with a time-varying field to deflect out-of-time protons, and a system to measure the extinction of out-of-time beam particles incident on the muon production target. These proceedings summarize the systems that have been designed to achieve the required level of extinction and to continuously place limits on the presence of out-of-time beam hitting the production target with a sensitivity of <1e-10.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Between Harmonic Crystal and Glass: Solids with Dimpled Potential-Energy Surfaces Having Multiple Local Energy Minima

Solids with dimpled potential-energy surfaces are ubiquitous in nature and, typically, exhibit structural (elastic or phonon) instabilities. Dimpled potentials are not harmonic; thus, the conventional quasiharmonic approximation at finite temperatures fails to describe anharmonic vibrations in such solids. At sufficiently high temperatures, their crystal structure is stabilized by entropy; in this phase, a diffraction pattern of a periodic crystal is combined with vibrational properties of a phonon glass. As temperature is lowered, the solid undergoes a symmetry-breaking transition and transforms into a lower-symmetry phase with lower lattice entropy. Here, we identify specific features in the potential-energy surface that lead to such polymorphic behavior; we establish reliable estimates for the relative energies and temperatures associated with the anharmonic vibrations and the solid–solid symmetry-breaking phase transitions. We show that computational phonon methods can be applied to address anharmonic vibrations in a polymorphic solid at fixed temperature. To illustrate the ubiquity of this class of materials, we present a range of examples (elemental metals, a shape-memory alloy, and a layered charge-density-wave system); we show that our theoretical predictions compare well with known experimental data.

36 MATERIALS SCIENCE↗

Atmospheric Ion Composition, SGP, April-May 2023

These files contain select ion count rates measured by an atmospheric pressure interface time-of-flight mass spectrometer (APi-ToF) at the Atmospheric Radiation Measurement Southern Great Plains site from April 28, 2023 to May 31, 2023. Files are in ICARTT format. The APi-ToF measures the chemical composition of naturally charged ions using mass spectrometry. Due to the nature of the measurements, time-series data are non-quantitative. This dataset contains time-series information for the ions that are typically the most intense ions observed.

54 ENVIRONMENTAL SCIENCES↗

Shielding techniques.

Charged-particle shielding technology for spacecraft noting particle interaction with matter, penetration calculation and amassed data

SPACECRAFT SHIELDING↗

The charge composition aspect of energetic trapped particles

Three possible sources of particle species important to the energy balance of the magnetosphere are discussed, with special emphasis on particles with different charge-to-mass ratios. Possibilities for various experimental tests are pointed out. Some recent experimental data on geomagnetically trapped alpha particles are compared with relevant results of current theoretical work. An experiment is proposed that is likely to provide quantitative indications for the energization and loss processes affecting ionic particle species in the magnetosphere.

Krimigis, S. M.↗

A novel negative-limited sealed nickel-cadmium cell

The use of negative-limited nickel-cadmium cells with adequate charge control is shown to provide an effective means for controlling internal pressure. Cycle test data show that negative-limited cells have somewhat higher ampere-hour degradation rates at higher operating temperatures. The most important advantages of these cells are: (1) lesser heat generation during operation; (2) longer separator life, as a result of operation at lower temperatures; (3) decreased stresses on cell seals due to lower operating pressures; and (4) significant weight savings.

Juvinall, G. L.↗

A simulation model of time-dependent plasma-spacecraft interactions

A plasma simulation code is presented that models the time-dependent plasma properties in the vicinity of a spherical, charged spacecraft. After showing agreement with analytic, steady-state theories and ATS-6 satellite data, the following three problems are treated: (1) transient pulses from photoemission at various emission temperatures and ambient plasma conditions, (2) spacecharge limited emission, and (3) simulated plasma oscillations in the long wavelength limit.

Rothwell, P. L.↗

Real-time video-image analysis

Digitizer and storage system allow rapid random access to video data by computer. RAPID (random-access picture digitizer) uses two commercially-available, charge-injection, solid-state TV cameras as sensors. It can continuously update its memory with each frame of video signal, or it can hold given frame in memory. In either mode, it generates composite video output signal representing digitized image in memory.

Eskenazi, R.↗

Calculation of total cross sections for charge exchange in molecular collisions

Areas of investigation summarized include nitrogen ion-nitrogen molecule collisions; molecular collisions with surfaces; molecular identification from analysis of cracking patterns of selected gases; computer modelling of a quadrupole mass spectrometer; study of space charge in a quadrupole; transmission of the 127 deg cylindrical electrostatic analyzer; and mass spectrometer data deconvolution.

Ioup, J.↗

Detection of auroral hydrogen Lyman-alpha emission from Uranus

A series of observations of Uranus obtained with the short-wavelength spectrograph of the International Ultraviolet Explorer Observatory in 1982 April and June have revealed unexpectedly strong H Lyman-alpha emission which varied between 430 and 850 rayleighs in observed disk-averaged brightness over the course of these observations. The variability of the emission alone indicates that much of the emission must be produced by charged particle excitation of H in Uranus's upper atmosphere. In addition, comparison of these data with a model for resonant scattering of solar H Lyman-alpha emission indicates that, over a wide range of model conditions, an emission brightness of even 430 rayleighs (which was the lowest observed value) corresponds to an H column density on the order of 10 to the 17th/sq cm in Uranus's upper atmosphere. These data offer the first strong evidence for the presence of aurorae and therefore a magnetic field on Uranus.

Clarke, J. T.↗

Further analysis of a recent cosmic-ray antiproton experiment

Reference is made to the measurements of a cosmic ray antiproton flux at a few hundred MeV reported by Buffington et al. (1981), noting that one of the final background processes to be removed by the data analysis in that study was helium-induced events which satisfied the criteria for topology and timing. The response in the third scintillator S3 was used to identify and remove these events. For the top two scintillators S1 and S2, pulse size information was lost during the data-taking. A method is reported here for the partial retrieval of pulse size information for the scintillator S2. This is possible because a portion of this signal was subtracted from the Cerenkov response before trigger discrimination and data recording to remove scintillation from the Cerenkov response. For separating protons from more highly charged particles, the method is considered sufficient. It is pointed out that the sample of events identified as antiprotons, for which the method can be applied, has the expected unit charge in scintillator S2.

Buffington, A.↗

Two-dimensional infrared detector arrays

An introduction to overall IR array concepts and particular array designs is presented, and examples of laboratory and observational data obtained with IR arrays are given. Hybrid array designs, extrinsic silicon accumulation-mode charge injection devices, and switched-FET or switched-sample photoconductor techniques are summarized. Three recent astronomical observation projects which used IR arrays are examined.

Mccreight, C. R.↗

Heavy doping effects in high efficiency silicon solar cells

The temperature dependence of the emitter saturation current for bipolar devices was studied by varying the surface recombination velocity at the emitter surface. From this dependence, the value was derived for bandgap narrowing that is in better agreement with other determinations that were obtained from the temperature dependence measure on devices with ohmic contacts. Results of the first direct measurement of the minority-carrier transit time in a transparent heavily doped emitter layer were reported. The value was obtained by a high-frequency conductance method recently developed and used for doped Si. Experimental evidence is presented for significantly greater charge storage in highly excited silicon near room temperature than conventional theory would predict. These data are compared with various data for delta E sub G in heavily doped silicon.

Lindholm, F. A.↗

An experimental investigation of the plasma contacting process

Measurements including plasma potential profile measurements made on a simple hollow cathode plasma contactor operating in the electron collection and emission modes are described. The ignited electron collection mode of contactor operation is identified, shown to improve contactor performance and found to be facilitated by increasing the size of the contactor anode. Potential profile data are compared to the predictions of a simple theoretical model that describes space-charge-current limitations imposed by the formation of a double sheath and found to agree with each other to within about + or - 25 percent. Because electrons, which are the dominant charge carriers, tend to be emitted from the hollow cathode in the emission mode and collected by the anode in the collection mode it is suggested that operation at high electrodynamic tether currents will probably require switching the point of tether connection to the contactor between its cathode and anode when the direction of tether current is reversed.

Wilbur, Paul J.↗