Elastic Scattering Research Articles

Coherent elastic neutrino nucleus scatter response of semiconductor detectors to nuclear reactor antineutrinos

We studied the performance of advanced semiconductor detectors to measure reactor antineutrino with the potential to drastically improve efficiency and lower existing thresholds of detectable incident-antineutrino-energy. Recent developments, such as those by the Mitchell Institute Neutrino Experiment at Reactor (MINER) experiment at Texas A&M University, in semiconductor technologies have enabled the ability to lower the coherent-elastic-neutrino-nucleus-scatter (CEνNS) based detection threshold to nuclear recoil energies between 10-eV and 100-eV (Dutta et al., 2016). Existing detectors based on inverse beta decay (IBD) have a threshold of 1.806 MeV (Oralbaev et al., 2016). In this study, we calculated the CEνNS response of semiconductor detectors to antineutrino flux from a 1-MW(th) TRIGA reactor as a function of incident antineutrino energy. In the calculations, the reaction rates of detectors made of germanium and silicon are calculated for a 100-kg detector and placed 10 m from the core. No background radiation characterization and reduction were performed. First, the reactor antineutrino flux spectrum is obtained for the fuel composition specific to 1-MW(th) TRIGA reactor without any thresholds. Next, the standard model (SM) of physics is used to calculate the CEνNS cross-section as a function of incident antineutrino energy. Finally, the above two functions are convolved to provide the detector response for both, germanium and silicon detectors. The results show that germanium has a greater efficiency than silicon; however, it is shown that silicon is sensitive to lower antineutrino energies. It is found that a 100-eV nuclear recoil in germanium semiconductor detectors can be produced by a minimum incident energy of 1.84 MeV antineutrinos, and in silicon by 1.14 MeV antineutrinos. For the lower threshold, a 20-eV nuclear recoil in germanium semiconductors can be produced by a minimum incident energy of 0.82 MeV antineutrinos and in Si by 0.51 MeV antineutrinos. Lowering the detector response energy sensitivity equips us with newer techniques for nuclear fuel monitoring.

Relation between transition density and proton inelastic scattering by C12 target at Ep=65 and 200 MeV

We calculate proton elastic and inelastic scatterings with a microscopic coupled channel (MCC) calculation. The localized diagonal and coupling potentials including the spin-orbit part are obtained by folding a complex $G$-matrix effective nucleon-nucleon interaction with a transition density. This is the first time that the present folding prescription for the spin-orbit part is applied to the proton inelastic scattering, while for the monopole transition only. We apply the MCC calculation to the proton elastic and inelastic $({0}_{2}^{+})$ scatterings by $^{12}\mathrm{C}$ target at ${E}_{p}=65 \mathrm{and} 200 \mathrm{MeV}$. The role of diagonal and coupling potentials for the central and spin-orbit parts is checked. In addition, the relation between the transition density and the proton inelastic scattering is investigated with the modified wave function and the modified transition density. Namely, we perform the investigation with the artificial drastic change rather than fine structural change. The inelastic cross section is sensitive to the strength and shape of the transition density, but the inelastic analyzing power is sensitive only to the shape of that. Finally, we make clear the property of the inelastic analyzing power derived from the transition density without an ambiguity.

Elastic Scattering with Double Folding Model: 8B+27Al

In the present work, the elastic scattering of the 8B+27Al reaction at two different energies have been examined using the microscopic double folding potential approximation within the framework of the optical model. The real part of the optical model has been obtained by using Fermi, Gaussian and Variational Monte Carlo (VMC) density distributions in the microscopic double folding model and the imaginary part has been taken as Woods-Saxon volume type. The results of our microscopic analysis are quite compatible with the experimental cross-section data. The reaction cross sections, the volume integrals of used potentials and their χ2/N errors have also been computed. This study is important in showing the effect of microscopically derived potentials in explaining the 8B+27Al experimental data published recently.

Atomic scale Monte-Carlo simulations of neutron diffraction experiments on stoichiometric uranium dioxide up to 1664 K

The neutron transport in nuclear fuels depends on the crystalline structure of materials when neutron energies lie below a few eV. For that purpose, the theoretical formalism that describes the neutron elastic and inelastic scatterings by crystals has been implemented in the CINEL processing tool in order to provide temperature-dependent neutron cross sections usable by the Monte-Carlo code TRIPOLI4®. The performances of the Monte-Carlo calculations are illustrated with the analysis of neutron powder diffraction data on UO2 measured up to 1664 K with the D4 and D20 diffractometers of the Institute Laue–Langevin (Grenoble, France). The comparison of the experimental and simulated pair distribution functions confirms the unusual decrease of the U–O atomic distances with increasing temperature when an ideal fluorite structure (Fm3̄m space group) with harmonic atomic vibrations is assumed over the full temperature range. The flexibility of the CINEL code allowed to explore disorder or anharmonic oxygen vibrations in the Fm3̄m space group by using either a four-site model with a relaxation term or a structure factor equation with a non-zero anharmonic third-cumulant coefficient. As none of these models succeeded to improve the agreement with the experiments, recent works that propose other local crystalline symmetries for UO2 at elevated temperatures were investigated with the CINEL code. The case of the Pa3̄ symmetry is briefly discussed in this paper.

Determination of spin diffusion length in Bi [formula omitted]-doped Cu films by weak antilocalization measurements

Working with the weak antilocalization measurements, we investigate the spin diffusion length in Bi δ-doped Cu films with the fine-tuned Bi concentration. By exploiting the long spin diffusion length of Cu and the strong spin-orbit coupling of Bi with the δ-doping technique, the spin diffusion length can be tuned artificially. Furthermore, it is found that the spin relaxation is dominated by elastic scatterings from Bi impurities in Bi δ-doped Cu systems, which follows the Elliott-Yafet mechanism.

An Analysis of Elastic Scattering Angular Distributions of $$^{17}$$F on a $$^{208}$$Pb Target at Different Energies

This study investigated the elastic scattering of a $$^{\mathrm {17}}$$ F $$+^{\mathrm {208}}$$ Pb system at different energies using the Continuum-Discretized Coupled Channels (CDCC) method. A microscopic optical model was selected and double-folding potential was used for the $$^{\mathrm {16}}$$ O $$+$$ target interaction. The real part of the optical model was determined as folding potential and the imaginary part of the optical model was taken as standard volume Woods–Saxon shape. Single-channel and multi-channel CDCC calculations were performed to determine the effect of excited channels. An elastic scattering cross section of the $$^{\mathrm {17}}$$ F $$+^{\mathrm {208}}$$ Pb system was calculated and its compatibility with experimental data was determined.

Initial State Interaction for the 20Ne + 130Te and 18O + 116Sn Systems at 15.3 AMeV from Elastic and Inelastic Scattering Measurements

Double charge exchange (DCE) reactions could provide experimentally driven information about nuclear matrix elements of interest in the context of neutrinoless double-β decay. To achieve this goal, a detailed description of the reaction mechanism is mandatory. This requires the full characterization of the initial and final-state interactions, which are poorly known for many of the projectile-target systems involved in future DCE studies. Among these, we intend to study the 20Ne + 130Te and 18O + 116Sn systems at 15.3 AMeV, which are particularly relevant due to their connection with the 130Te→130Xe and 116Cd→116Sn double-β decays. We measure the elastic and inelastic scattering cross-section angular distributions and compare them with theoretical calculations performed in the optical model, one-step distorted wave Born approximation, and coupled-channel approaches using the São Paulo double-folding optical potential. A good description of the experimental data in the whole explored range of transferred momenta is obtained provided that couplings with the 21+ states of the projectile and target are explicitly included within the coupled-channel approach. These results are relevant also in the analysis of other quasi-elastic reaction channels in these systems, in which the same couplings should be included.

IBAT: A new ion beam batch analysis tool for thin samples

We present a new analysis tool and user interface for batch analysis of PIXE, PIGE, RBS and PESA spectra of thin samples. IBA analysis techniques are ideally suited for aerosol filter analysis, because of their high sensitivity and because the layer of aerosol material deposited on the filters is very thin. The analysis tool provides an easy interface for the MS-DOS executable of the GUPIX package, combined with newly developed software for Proton Induced Gamma Emission (PIGE), Rutherford Back Scattering (RBS) and Proton Elastic Scattering Analysis (PESA). For PIGE and PESA background subtraction techniques are applied to extract the gamma and hydrogen recoil peaks and calculate concentrations using suitable calibrations standards. For RBS a similar technique is applied to extract estimates for C, N and O. The results of this new analysis tool will be compared with results obtained from the PIXAN package used previously. The data will also be checked for internal consistencies within aerosol data sets using source apportionment techniques.

Influence of Deformed Surface Diffuseness on Elastic Scattering Reactions Involving Actinide and Lanthanide Targets

The effect of the deformed surface diffuseness on the elastic scattering reactions with actinide and lanthanide targets is examined. The elastic scattering cross-sections are calculated by assuming the spherical structure for the projectiles and both spherical and deformed structures for the target nuclei. The theoretical calculations are performed by using spherical and deformed Broglie–Winther potentials for the real potential and the Woods–Saxon potential for the imaginary potential in the framework of the optical model. Finally, the effect of the angle dependence on the deformed surface diffuseness for two different orientation angles such as 0 = п/4 and 0 = п/2 is studied. All the theoretical results are compared with both one another and experimental data.

Elastic Light Scatter Pattern Analysis for the Expedited Detection of Yersinia Species in Pork Mince: Proof of Concept.

Isolation of the pathogens Yersinia enterocolitica and Yersinia pseudotuberculosis from foods typically rely on slow (10–21 day) “cold enrichment” protocols before confirmed results are obtained. We describe an approach that yields results in 39 h that combines an alternative enrichment method with culture on a non-selective medium, and subsequent identification of suspect colonies using elastic light scatter (ELS) analysis. A prototype database of ELS profiles from five Yersinia species and six other bacterial genera found in pork mince was established, and used to compare similar profiles of colonies obtained from enrichment cultures from pork mince samples seeded with representative strains of Y. enterocolitica and Y. pseudotuberculosis. The presumptive identification by ELS using computerised or visual analyses of 83/90 colonies in these experiments as the target species was confirmed by partial 16S rDNA sequencing. In addition to seeded cultures, our method recovered two naturally occurring Yersinia strains. Our results indicate that modified enrichment combined with ELS is a promising new approach for expedited detection of foodborne pathogenic yersiniae.

Constraints on Elastic Neutrino Nucleus Scattering in the Fully Coherent Regime from the CONUS Experiment.

We report the best limit on coherent elastic scattering of electron antineutrinos emitted from a nuclear reactor off germanium nuclei. The measurement was performed with the CONUS detectors positioned at 17.1m from the 3.9 GW_{th} reactor core of the nuclear power plant in Brokdorf, Germany. The antineutrino energies of less than 10MeV assure interactions in the fully coherent regime. The analyzed dataset includes 248.7kgd with the reactor turned on and background data of 58.8kgd with the reactor off. With a quenching parameter of k=0.18 for germanium, we determined an upper limit on the number of neutrino events of 85 in the region of interest at 90%confidence level. This new CONUS dataset disfavors quenching parameters above k=0.27, under the assumption of standard-model-like coherent scattering of the reactor antineutrinos.

Two-Photon Exchange in Elastic Electron Scattering on Hadronic Systems

In the present review, we discuss different aspects of the two-photon exchange (TPE) physics in elastic ep scattering at high Q2, as well as at low Q2. The imaginary part of the TPE amplitude gives rise to beam and target single-spin asymmetries. Different theoretical approaches to the calculation of these observables are considered. The real part of the TPE amplitude influences the unpolarized cross-section and double-spin observables and is, most likely, responsible for the discrepancy between two methods of measurements of the proton form factors. We review different methods of calculations of the TPE amplitudes in the framework of the “hadron” and “quark-gluon” approaches. We discuss the dispersion approach suitable for low and intermediate Q2, which includes elastic and inelastic intermediate hadronic states, as well as the connection of TPE with the proton radius puzzle. The present situation with direct experimental searches for the TPE amplitude in the e+p/e−p charge asymmetry is also discussed, as well as attempts to extract the TPE amplitudes from existing experimental data obtained by the Rosenbluth and double polarization techniques. The TPE physics in other processes such as elastic мp, e-nucleus, and еп scattering is also reviewed.

Nucleon Structure and Spin Effects in Elastic Hadron Scattering

Soft diffraction phenomena in elastic nucleon scattering are considered from the viewpoint of the spin dependence of the interaction potential. Spin-dependent pomeron effects are analyzed for elastic pp scattering, and spin-dependent differential cross sections and spin correlation parameters are calculated. The spin correlation parameter AN is examined on the basis of experimental data from s=4.9 GeV up to 23.4GeV in the framework of the extended High Energy Generalized Structure (HEGS) model. It is shown that the existing experimental data of proton-proton and proton-antiproton elastic scattering at high energy in the region of the diffraction minimum and at large momentum transfer give the support of the existence of the energy-independent part of the hadron spin flip amplitude.

Single‐Particle Characterization by Elastic Light Scattering

AbstractThe field of light‐scattering characterization of single particles has seen a rapid growth over the last 30 years largely due to the progress in measurement and simulation capabilities. In particular, several methods have been developed to reliably characterize various particles, described by a model with several characteristics, with geometric resolution significantly better than the diffraction limit. However, their development has been largely fragmentary, limited to specific experimental set‐ups. To fill this gap, these lines of development are reviewed within a unified framework. While focusing on characterization algorithms themselves, the experimental aspects related to the isolation and measurement of single particles are also discussed. The existing characterization methods are divided into three classes. The widest class is that of model‐driven methods based on solving parametric inverse light‐scattering problems, using a direct inversion of a low‐dimensional mapping, a nonlinear regression, or neural networks. Other classes include model‐free reconstruction methods and data‐driven classification methods. This review is designed to be extensive in including all relevant literature, but the discussion of semi‐quantitative imaging methods, such as tomography or holography‐based reconstruction, is deliberately omitted. Throughout the review the development of various characterization methods is described, they are critically compared, and promising directions of future research are highlighted.

Elastic Electron Scattering from Methane Molecule in the Energy Range from 50-300 eV.

Electron interaction with methane molecule and accurate determination of its elastic cross-section is a demanding task for both experimental and theoretical standpoints and relevant for our better understanding of the processes in Earth’s and Solar outer planet atmospheres, the greenhouse effect or in plasma physics applications like vapor deposition, complex plasma-wall interactions and edge plasma regions of Tokamak. Methane can serve as a test molecule for advancing novel electron-molecule collision theories. We present a combined experimental and theoretical study of the elastic electron differential cross-section from methane molecule, as well as integral and momentum transfer cross-sections in the intermediate energy range (50–300 eV). The experimental setup, based on a crossed beam technique, comprising of an electron gun, a single capillary gas needle and detection system with a channeltron is used in the measurements. The absolute values for cross-sections are obtained by relative-flow method, using argon as a reference. Theoretical results are acquired using two approximations: simple sum of individual atomic cross-sections and the other with molecular effect taken into the account.

First Measurement of Coherent Elastic Neutrino-Nucleus Scattering on Argon.

We report the first measurement of coherent elastic neutrino-nucleus scattering (CEvNS) on argon using a liquid argon detector at the Oak Ridge National Laboratory Spallation Neutron Source. Two independent analyses prefer CEvNS over the background-only null hypothesis with greater than 3σ significance. The measured cross section, averaged over the incident neutrino flux, is (2.2±0.7)×10^{-39} cm^{2}-consistent with the standard model prediction. The neutron-number dependence of this result, together with that from our previous measurement on CsI, confirms the existence of the CEvNS process and provides improved constraints on nonstandard neutrino interactions.

Elastic and Inelastic Scattering of 9,10,11Be by 64Zn and 120Sn Nuclei at Different Energies

Elastic and Inelastic Scattering of 9,10,11Be by 64Zn and 120Sn Nuclei at Different Energies

Nuclear Mean-Field Description of Proton Elastic Scattering by \(^{12,13}\)C at Low Energies

Nuclear reactions of proton by light nuclei at low energies play a key role in the study of nucleosynthesis which is of interest in nuclear astrophysics. The most fundamental process which is very necessary is the elastic scattering. In this work, we construct a microscopic proton-nucleus potential in order to describe the differential cross-sections over scattering angles of the proton elastic scattering by \(^{12}\)C and \(^{13}\)C in the range of available energies 14 - 22 MeV. The microscopic optical potential is based on the folding model using the effective nucleon-nucleon interaction CDM3Yn. The results show the promising use of the CDM3Yn interactions at low energies, which were originally used for nuclear reactions at intermediate energies. This could be the premise for the study of nuclear reactions using CDM3Yn interaction in astrophysics at low energies.

From Elastic Scattering to Central Exclusive Production: Physics with Forward Protons at RHIC

We describe a physics program at the Relativistic Heavy Ion Collider (RHIC) with tagged forward protons. The program started with the proton-proton elastic scattering experiment (PP2PP), for which a set of Roman Pot stations was build. The PP2PP experiment took data at RHIC as a dedicated experiment at the beginning of RHIC operations. To expand the physics program to include non-elastic channels with forward protons, like Central Exclusive Production (CEP), Central Production (CP) and Single Diffraction Dissociation (SD), the experiment with its equipment was merged with the STAR experiment at RHIC. Consequently the expanded program, which included both elastic and inelastic channels became part of the physics program and operations of the STAR experiment. In this paper we shall describe the physics results obtained by the PP2PP and STAR experiments to date.

Coulomb-nuclear Interference in Elastic Scattering: Eikonal Calculation to All Orders of \(\alpha \)

The Coulomb-nuclear interference (CNI) has recently been used by the TOTEM Collaboration to analyse proton-proton elastic-scattering data from the LHC and to draw physics conclusions. This paper will present an eikonal calculation of the CNI effects performed to all orders of the fine structure constant, $\alpha$. This calculation will be used as a reference to benchmark several widely-used CNI formulae and to verify several recent claims by other authors.