Proton-Proton Elastic Scattering Excitation Functions at Intermediate Energies
Albers, D.; Bisplinghoff, J.; Bollmann, R.; Büßer, K.; Cloth, P.; Daniel, R.; Diehl, O.; Dohrmann, F.; Engelhardt, H. P.; Ernst, J.; Eversheim, P. D.; Gasthuber, M.; Gebel, R.; Greiff, J.; Groß, A.; Groß-Hardt, R.; Heider, S.; Heine, A.; Hinterberger, F.; Igelbrink, M.; Jahn, R.; Jeske, M.; Lahr, U.; Langkau, R.; Lindlein, J.; Maier, R.; Maschuw, R.; Mayer-Kuckuk, T.; Mosel, F.; Müller, M.; Münstermann, M.; Prasuhn, D.; Rohdjeß, H.; Rosendaal, D.; Roß, U.; von Rossen, P.; Scheid, H.; Schirm, N.; Schulz-Rojahn, M.; Schwandt, F.; Schwarz, V.; Scobel, W.; Sterzenbach, G.; Trelle, H. J.; Wellinghausen, A.; Wiedmann, W.; Woller, K.; Ziegler, R.
1997-03-01
Excitation functions of proton-proton elastic scattering cross sections have been measured in narrow steps for projectile momenta pp (energies Tp) from 1100 to 3300 MeV/c (500 to 2500 MeV) in the angular range 35°<=Θc.m.<=90° with a detector providing ΔΘc.m.~1.4° resolution. Measurements have been performed continuously during projectile acceleration in the cooler synchrotron COSY with an internal CH2 fiber target, taking particular care to monitor luminosity as a function of Tp. The advantages of this experimental technique are demonstrated, and the excitation functions obtained are compared to existing cross section data. No evidence for narrow structures was found.
Proton-Proton Elastic Scattering Excitation Functions at Intermediate Energies
Energy Technology Data Exchange (ETDEWEB)
Bisplinghoff, J.; Daniel, R.; Diehl, O.; Engelhardt, H.; Ernst, J.; Eversheim, P.; Gro-Hardt, R.; Heider, S.; Heine, A.; Hinterberger, F.; Jahn, R.; Jeske, M.; Lahr, U.; Maschuw, R.; Mayer-Kuckuk, T.; Mosel, F.; Rohdje, H.; Rosendaal, D.; Ro, U.; Scheid, H.; Schulz-Rojahn, M.; Schwandt, F.; Schwarz, V.; Trelle, H.; Wiedmann, W.; Ziegler, R. [Inst.fuer Strahlen- und Kernphysik, Universitaet Bonn, D-53115 Bonn (Germany); Albers, D.; Bollmann, R.; Bueer, K.; Dohrmann, F.; Gasthuber, M.; Greiff, J.; Gro, A.; Igelbrink, M.; Langkau, R.; Lindlein, J.; Mueller, M.; Muenstermann, M.; Schirm, N.; Scobel, W.; Wellinghausen, A.; Woller, K. [I. Inst.fuer Experimentalphysik, Universitaet Hamburg, D-22761 Hamburg (Germany); Cloth, P.; Gebel, R.; Maier, R.; Prasuhn, D.; von Rossen, P.; Sterzenbach, G. [Inst.fuer Kernphysik, KFA Juelich, Juelich (Germany)
1997-03-01
Excitation functions of proton-proton elastic scattering cross sections have been measured in narrow steps for projectile momenta p{sub p} (energies T{sub p}) from 1100 to 3300MeV/c (500 to 2500MeV) in the angular range 35{degree}{le}{Theta}{sub c.m.}{le}90{degree} with a detector providing {Delta}{Theta}{sub c.m.}{approx}1.4{degree} resolution. Measurements have been performed continuously during projectile acceleration in the cooler synchrotron COSY with an internal CH{sub 2} fiber target, taking particular care to monitor luminosity as a function of T{sub p}. The advantages of this experimental technique are demonstrated, and the excitation functions obtained are compared to existing cross section data. No evidence for narrow structures was found. {copyright} {ital 1997} {ital The American Physical Society}
Elastic proton-deuteron scattering at intermediate energies
Ramazani-Moghaddam-Arani, A.; Amir-Ahmadi, H. R.; Bacher, A. D.; Bailey, C. D.; Biegun, A.; Eslami-Kalantari, M.; Gasparic, I.; Joulaeizadeh, L.; Kalantar-Nayestanaki, N.; Kistryn, St.; Kozela, A.; Mardanpour, H.; Messchendorp, J. G.; Micherdzinska, A. M.; Moeini, H.; Shende, S. V.; Stephan, E.; Stephenson, E. J.; Sworst, R.; Eslamikalantari, M.
Observables in elastic proton-deuteron scattering are sensitive probes of the nucleon-nucleon interaction and three-nucleon force effects. The present experimental database for this reaction is large, but contains a large discrepancy between data sets for the differential cross section taken at 135
Analysis of the low-energy $\\pi^\\pm p$ elastic-scattering data
Matsinos, Evangelos; Rasche, Guenther
2012-01-01
We report the results of a phase-shift analysis (PSA) of the low-energy $\\pi^\\pm p$ elastic-scattering data. Following the method which we had set forth in our previous PSA (Matsinos et al., 2006), we first investigate the self-consistency of the low-energy $\\pi^\\pm p$ elastic-scattering databases, via two separate analyses of (first) the $\\pi^+ p$ and (subsequently) the $\\pi^- p$ elastic-scattering data. There are two main differences to our previous PSA: a) we now perform only one test for ...
Analysis of α-12C elastic scattering at intermediate energies by the S-matrix model
Berezhnoy, Yu. A.; Onyshchenko, G. M.; Pilipenko, V. V.
The results of calculations of differential cross-sections for α-12C elastic scattering by the S-matrix model are presented for 10 energy values in the energy range 65MeV ≤ Eα ≤ 386MeV in a wide range of scattering angles. The behavior of various scattering characteristics as functions of the projectile energy is analyzed. It is shown that the chosen parametrization of S-matrix allows describing correctly the Fraunhofer oscillations of the cross-sections in the region of small scattering angles and the rainbow scattering pattern in the region of sufficiently large angles.
Magazù, Salvatore; Migliardo, Federica; Benedetto, Antonio
2011-10-01
The main aim of this paper is to present the scientific case of the resolution elastic neutron scattering (RENS) method that is based on the collection of elastic neutron scattering intensity as a function of the instrumental energy resolution and that is able to extract information on the system dynamical properties from an elastic signal. In this framework, it is shown that in the measured elastic scattering law, as a function of the instrumental energy resolution, an inflection point occurs when the instrumental energy resolution intersects the system relaxation time, and in an equivalent way, a transition in the temperature behavior of the measured elastic scattering law occurs when the characteristic system relaxation time crosses the instrumental energy resolution time. With regard to the latter, an operative protocol to determine the system characteristic time by different elastic incoherent neutron scattering (EINS) thermal scans at different instrumental energy resolutions is also proposed. The proposed method, hence, is not primarily addressed to collect the measured elastic scattering intensity with a great accuracy, but rather relies on determining an inflection point in the measured elastic scattering law versus instrumental energy resolution. The RENS method is tested both numerically and experimentally. As far as numerical simulations are concerned, a simple model system for which the temperature behavior of the relaxation time follows an Arrhenius law, while its scattering law follows a Gaussian behavior, is considered. It is shown that the system relaxation time used as an input for the simulations coincides with the one obtained by the RENS approach. Regarding the experimental findings, due to the fact that a neutron scattering spectrometer working following the RENS method has not been constructed yet, different EINS experiments with different instrumental energy resolutions were carried out on a complex model system, i.e., dry and D(2)O hydrated
Impact picture for near-forward elastic scattering up to LHC energies
Soffer, Jacques; Wu, Tai Tsun
2015-01-01
We will recall the main feaatures of an accurate phenomenological model to describe successfully near-forward elastic scattering in a wide energy range, including ISR, SPS and Tevatron colliders. A large step in energy domain is accomplished with the LHC collider, presently running, giving the opportunity to confront the new data with the predictions of our theoretical approach.
Liu, Haitao
2013-10-07
We propose a coherent-form energy conservation relation (ECR) that is generally valid for the elastic transmission and reflection of a guided mode in a symmetric scattering system. In contrast with the classical incoherent-form ECR, |τ|2 + |ρ|2≤1 with τ and ρ denoting the elastic transmission and reflection coefficients of a guided mode, the coherent-form ECR is expressed as |τ + ρ|≤1, which imposes a constraint on a coherent superposition of the transmitted and reflected modes. The coherent-form ECR is rigorously demonstrated and is numerically tested by considering different types of modes in various scattering systems. Further discussions with the scattering matrix formalism indicate that two coherent-form ECRs, |τ + ρ|≤1 and |τ-ρ|≤1, along with the classical ECR |τ|2 + |ρ|2≤1 constitute a complete description of the energy conservation for the elastic scattering of a guided mode in a symmetric scattering system. The coherent-form ECR provides a common tool in terms of energy transfer for understanding and analyzing the scattering dynamics in currently interested scattering systems.
An energy-dependent phase shift analysis of low-energy proton-deuteron elastic scattering
Energy Technology Data Exchange (ETDEWEB)
Black, T.-C.; Karwowski, H.-J.; Ludwig, E.-J. [North Carolina Univ., Chapel Hill (United States). Dept. of Physics and Astronomy]|[Triangle Universities Nuclear Laboratory, Durham, NC 27708 (United States); Kievsky, A.; Rosati, S.; Viviani, M. [Istituto Nazionale di Fisica Nucleare, Piazza Torricelli 2, 56100 Pisa (Italy)
1998-03-02
An energy dependent phase shift analysis of p+d elastic scattering below the deuteron breakup threshold has been conducted. The phases are fit directly to the data with a Monte Carlo Markov chain algorithm after being sampled from a parameter space which is constrained to satisfy the Coulomb-modified effective range expansion. The mixing parameters are required to obey analyticity constraints. The overall fit in the preliminary analysis reported here was satisfactory, giving a {chi}{sup 2}/datum of about 2.5. The analysis indicates the existence of a singularity in the spin-doublet S-wave effective range function. The inferred value of the quartet S-wave scattering length is in excellent quantitative agreement with theoretical predictions. Small changes to the theoretical P-wave phase shifts and somewhat larger changes to the theoretical J=1/2 mixing parameters are required to reproduce the p+d data. (orig.) 9 refs.
E710, $p\\bar{p}$ Elastic Scattering at Tevatron Energies
Energy Technology Data Exchange (ETDEWEB)
Sadr, Sasan [Northwestern Univ., Evanston, IL (United States)
1993-11-01
Experiment E710, located at site EO of the Tevatron collider at Fermilab, was conceived in order to measure $p\\bar{p}$ elastic scattering. The measured parameters were: the total cross section $\\sigma_t$, the ratio of the real to the imaginary part of the forward scattering amplitude $p$, the nuclear slope parameter B, the nuclear curvature parameter C, the total elastic cross section $\\sigma_{el}$, and the single diffractive cross section $\\sigma_{sd}$. These measurements were taken at center-of-mass energies of $\\sqrt{s}$= 1.02 and 1.8 TeV.
Elastic scattering phenomenology
Energy Technology Data Exchange (ETDEWEB)
Mackintosh, R.S. [The Open University, School of Physical Sciences, Milton Keynes (United Kingdom)
2017-04-15
We argue that, in many situations, fits to elastic scattering data that were historically, and frequently still are, considered ''good'', are not justifiably so describable. Information about the dynamics of nucleon-nucleus and nucleus-nucleus scattering is lost when elastic scattering phenomenology is insufficiently ambitious. It is argued that in many situations, an alternative approach is appropriate for the phenomenology of nuclear elastic scattering of nucleons and other light nuclei. The approach affords an appropriate means of evaluating folding models, one that fully exploits available empirical data. It is particularly applicable for nucleons and other light ions. (orig.)
Hishiyama, N.; Hoshino, M.; Blanco, F.; García, G.; Tanaka, H.
2017-12-01
We report absolute elastic differential cross sections (DCSs) for electron collisions with phosphorus trifluoride, PF3, molecules (e- + PF3) in the impact energy range of 2.0-200 eV and over a scattering angle range of 10°-150°. Measured angular distributions of scattered electron intensities were normalized by reference to the elastic DCSs of He. Corresponding integral and momentum-transfer cross sections were derived by extrapolating the angular range from 0° to 180° with the help of a modified phase-shift analysis. In addition, due to the large dipole moment of the considered molecule, the dipole-Born correction for the forward scattering angles has also been applied. As a part of this study, independent atom model calculations in combination with screening corrected additivity rule were also performed for elastic and inelastic (electronic excitation plus ionization) scattering using a complex optical potential method. Rotational excitation cross sections have been estimated with a dipole-Born approximation procedure. Vibrational excitations are not considered in this calculation. Theoretical data, at the differential and integral levels, were found to reasonably agree with the present experimental results. Furthermore, we explore the systematics of the elastic DCSs for the four-atomic trifluoride molecules of XF3 (X = B, N, and P) and central P-atom in PF3, showing that, owing to the comparatively small effect of the F-atoms, the present angular distributions of elastic DCSs are essentially dominated by the characteristic of the central P-atom at lower impact energies. Finally, these quantitative results for e- - PF3 collisions were compiled together with the previous data available in the literature in order to obtain a cross section dataset for modeling purposes. To comprehensively describe such a considerable amount of data, we proceed by first discussing, in this paper, the vibrationally elastic scattering processes whereas vibrational and electronic
Elastic α-{sup 12}C scattering at low energies in cluster effective field theory
Energy Technology Data Exchange (ETDEWEB)
Ando, Shung-Ichi [Sunmoon University, School of Mechanical and ICT Convergence Engineering, Asan, Chungnam (Korea, Republic of)
2016-05-15
The elastic α-{sup 12}C scattering at low energies is studied employing an effective field theory in which the α and {sup 12}C states are treated as elementary-like fields. We discuss scales of the theory in the stellar energy region where the {sup 12}C(α, γ){sup 16}O process occurs, and then obtain an expression of the elastic scattering amplitudes in terms of effective-range parameters. Using experimental data of the phase shifts for l=0,1, 2 channels at low energies, for which the resonance regions are avoided, we fix values of the parameters and find that the phase shifts at the low energies are well reproduced by using three effective-range parameters for each channel. Furthermore, we discuss problems and uncertainties of the present approach when the amplitudes are extrapolated to the stellar energy region. (orig.)
11. international conference on elastic and diffractive scattering: towards high energy frontiers
Energy Technology Data Exchange (ETDEWEB)
NONE
2005-07-01
This conference is held every 2 years. Every time these conferences on elastic and diffractive scattering adapt their content to the most recent experimental and theoretical results concerning not only quantum chromodynamics (QCD) but also other fields of particle physics where diffractive physics is present. This year, besides classical themes such as: -) forward scattering, -) total cross-sections, -) real parts, and -) pomeron and odderon, the participants have addressed many other subjects such as: -) LHC physics, -) non-perturbative approaches to high-energy scattering, -) the dipole model, -) small-x evolution, -) hard diffraction in QCD, -) nuclear shadowing, -) diffractive Higgs studies, -) spin effects, -) 4-quarks and 5-quarks, or -) B-physics.
Energy Technology Data Exchange (ETDEWEB)
Anderson, E. K.; Boadle, R. A.; Machacek, J. R.; Makochekanwa, C.; Sullivan, J. P. [ARC Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra 0200 (Australia); Chiari, L. [ARC Centre for Antimatter-Matter Studies, Flinders University, GPO Box 2100, Adelaide, 5001 SA (Australia); Buckman, S. J., E-mail: Stephen.buckman@anu.edu.au [ARC Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra 0200 (Australia); Institute of Mathematical Sciences, University of Malaya, Kuala Lumpur (Malaysia); Brunger, M. J. [ARC Centre for Antimatter-Matter Studies, Flinders University, GPO Box 2100, Adelaide, 5001 SA (Australia); Institute of Mathematical Sciences, University of Malaya, Kuala Lumpur (Malaysia); Garcia, G. [Instituto de Fısica Fundamental, Consejo Superior de Investigationes Cientıficas (CSIC), Serrano 113-bis, E-28006 Madrid (Spain); Blanco, F. [Departamento de Fısica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, E-28040 Madrid (Spain); Ingolfsson, O. [Department of Chemistry, Science Institute, University of Iceland, Reykjavík 107 (Iceland)
2014-07-21
Measurements of the grand total and total positronium formation cross sections for positron scattering from uracil have been performed for energies between 1 and 180 eV, using a trap-based beam apparatus. Angular, quasi-elastic differential cross section measurements at 1, 3, 5, 10, and 20 eV are also presented and discussed. These measurements are compared to existing experimental results and theoretical calculations, including our own calculations using a variant of the independent atom approach.
Investigation of {sup 17}F+p elastic scattering at near-barrier energies
Energy Technology Data Exchange (ETDEWEB)
El-Azab Farid, M. [Assiut University, Physics Department, Assiut (Egypt); Ibraheem, Awad A. [Al-Azhar University, Physics Department, Assiut (Egypt); King Khalid University, Physics Department, Abha (Saudi Arabia); Al-Hajjaji, Arwa S. [Taiz University, Physics Department, Taiz (Yemen)
2015-10-15
The {sup 17}F +p elastic scattering at two near-barrier energies of 3.5 and 4.3 MeV/nucleon, have been analyzed in the framework of the single folding approach. The folded potentials are constructed by folding the density-dependent (DDM3Y) effective nucleon-nucleon interaction over the nuclear density of the one-proton halo nucleus {sup 17}F. Two versions of the density are considered. In addition, two versions of the one-nucleon knock-on exchange potentials are introduced to construct the real microscopic potentials. The derived potentials supplemented by phenomenological Woods-Saxon imaginary and spin-orbit potentials produced excellent description of the differential elastic scattering cross sections at the higher energy without need to introduce any renormalization. At the lower energy, however, in order to successfully reproduce the data, it is necessary to reduce the strength of the constructed real DDM3Y potential by about 25% of its original value. Furthermore, good agreement with data is obtained using the extracted microscopic DDM3Y potentials for both real and imaginary parts. Moreover, the interesting notch test is applied to investigate the sensitivity of the elastic scattering cross section to the radial distribution of the constructed microscopic potentials. The extracted reaction (absorption) cross sections are, also, investigated. (orig.)
Elastic scattering of low energy electrons in partially ionized dense semiclassical plasma
Energy Technology Data Exchange (ETDEWEB)
Dzhumagulova, K. N., E-mail: dzhumagulova.karlygash@gmail.com; Shalenov, E. O.; Ramazanov, T. S. [IETP, Al Farabi Kazakh National University, 71al Farabi Street, Almaty 050040 (Kazakhstan)
2015-08-15
Elastic scattering of electrons by hydrogen atoms in a dense semiclassical hydrogen plasma for low impact energies has been studied. Differential scattering cross sections were calculated within the effective model of electron-atom interaction taking into account the effect of screening as well as the quantum mechanical effect of diffraction. The calculations were carried out on the basis of the phase-function method. The influence of the diffraction effect on the Ramsauer–Townsend effect was studied on the basis of a comparison with results made within the effective polarization model of the Buckingham type.
The calibration of elastic scattering angular distribution at low energies on HIRFL-RIBLL
Energy Technology Data Exchange (ETDEWEB)
Zhang, G.X. [School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191 (China); Zhang, G.L., E-mail: zgl@buaa.edu.cn [School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191 (China); Lin, C.J., E-mail: cjlin@ciae.ac.cn [China Institute of Atomic Energy, Beijing 102413 (China); Qu, W.W. [School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191 (China); School of Radiation Medicine and Protection, Medical College of Soochow University, Soochow 215123 (China); Yang, L.; Ma, N.R. [China Institute of Atomic Energy, Beijing 102413 (China); Zheng, L. [School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191 (China); Jia, H.M.; Sun, L.J. [China Institute of Atomic Energy, Beijing 102413 (China); Liu, X.X.; Chu, X.T.; Yang, J.C. [School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191 (China); Wang, J.S.; Xu, S.W.; Ma, P.; Ma, J.B.; Jin, S.L.; Bai, Z.; Huang, M.R. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Zang, H.L. [School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); and others
2017-02-21
The precise calibration of angular distribution of heavy-ion elastic scattering induced by Radioactive Ion Beams (RIBs) at energies around Coulomb barrier on the Radioactive Ion Beam Line in Lanzhou (RIBLL) at the Heavy-Ion Research Facility in Lanzhou (HIRFL) is presented. The beam profile and the scattering angles on the target are deduced by a measurement with two Multi Wire Proportional Chambers (MWPC), and four sets of detector telescopes (including Double-sided Silicon Strip Detectors (DSSD) placed systematically along the beam line, incorporating with Monte Carlo simulation. The MWPCs were used to determine the beam trajectory before the target, and the energies and the positions of scattered particles on the detectors were measured by the DSSDs. Minor corrections on the beam spot and the detector position are performed by assuming the pure Rutherford scattering at angles which are smaller than the related grazing angle. This method is applied for the elastic scattering of {sup 17}F on {sup 89}Y target at E{sub lab}=59 MeV and 50 MeV.
The calibration of elastic scattering angular distribution at low energies on HIRFL-RIBLL
Zhang, G. X.; Zhang, G. L.; Lin, C. J.; Qu, W. W.; Yang, L.; Ma, N. R.; Zheng, L.; Jia, H. M.; Sun, L. J.; Liu, X. X.; Chu, X. T.; Yang, J. C.; Wang, J. S.; Xu, S. W.; Ma, P.; Ma, J. B.; Jin, S. L.; Bai, Z.; Huang, M. R.; Zang, H. L.; Yang, B.; Liu, Y.
2017-02-01
The precise calibration of angular distribution of heavy-ion elastic scattering induced by Radioactive Ion Beams (RIBs) at energies around Coulomb barrier on the Radioactive Ion Beam Line in Lanzhou (RIBLL) at the Heavy-Ion Research Facility in Lanzhou (HIRFL) is presented. The beam profile and the scattering angles on the target are deduced by a measurement with two Multi Wire Proportional Chambers (MWPC), and four sets of detector telescopes (including Double-sided Silicon Strip Detectors (DSSD) placed systematically along the beam line, incorporating with Monte Carlo simulation. The MWPCs were used to determine the beam trajectory before the target, and the energies and the positions of scattered particles on the detectors were measured by the DSSDs. Minor corrections on the beam spot and the detector position are performed by assuming the pure Rutherford scattering at angles which are smaller than the related grazing angle. This method is applied for the elastic scattering of 17F on 89Y target at Elab=59 MeV and 50 MeV.
Energy-Dependent microscopic optical potential for p+{sup 9}Be elastic scattering
Energy Technology Data Exchange (ETDEWEB)
Maridi, H. M., E-mail: h.maridi@gmail.com [Physics Department, Faculty of Science, Cairo University, Giza 12613 (Egypt); Physics Department, Faculty of Applied Science, Taiz University, Taiz (Yemen); Farag, M. Y. H., E-mail: yehiafarag@cu.edu.eg; Esmael, E. H. [Physics Department, Faculty of Applied Science, Taiz University, Taiz (Yemen)
2016-06-10
The p+{sup 9}Be elastic scattering at an energy range up to 200 MeV/nucleon is analyzed using the single-folding model. The density- and isospin-dependent M3Y-Paris nucleon-nucleon (NN) interaction is used for the real part and the NN-scattering amplitude of the high-energy approximation for the imaginary one. The analysis reveals that the cross-section data are reproduced well at energies up to 100 MeV/nucleon by use of the partial-wave expansion. For higher energies, the eikonal approximation give results better than the partial-wave expansion calculations. The volume integrals of the optical-potential parts have systematic energy dependencies, and they are parameterized in empirical formulas.
Energy Technology Data Exchange (ETDEWEB)
Belyaeva, T.L.; Aguilera, E.F.; Perez T, R. [Universidad Autonoma del Estado de Mexico, C.P.50000 Toluca, Estado de Mexico (Mexico)
2004-12-01
An optical model analysis of the intermediate resonant structure for the 90 degrees elastic scattering and fusion excitation function at the low energy region E{sub cm} = 2.5 {approx} 19 MeV has been performed. Optical potentials with variable geometry were applied on the basis of a regular fit of the angular distributions at these energies. Calculations show that a strongly energy dependent interference picture, observed in the elastic scattering of {sup 12} C + {sup 12} C ions, can be successfully reproduced in the framework of the optical model. The resulting optical potential with an energy dependent adjusted power parameter and an also energy dependent imaginary strength W is valid to give a good description of the individual elastic-scattering angular distributions and to reproduce detailed features of the elastic-scattering and reaction excitation functions. (Author) 30 refs., 7 figs.
Total and elastic electron scattering cross sections from Xe at intermediate and high energies
Energy Technology Data Exchange (ETDEWEB)
Garcia, G [Instituto de Matematicas y Fisica Fundamental, CSIC, Serrano 123, 28006 Madrid (Spain); Pablos, J L de [Departamento de Fusion y Particulas Elementales, CIEMAT, Avenida Complutense 22, 28040 Madrid (Spain); Blanco, F [Departamento de Fisica Atomica Molecular y Nuclear, Universidad Complutense de Madrid, 28040 Madrid (Spain); Williart, A [Departamento de Fisica de los Materiales, UNED, Senda del Rey 9, 28040 Madrid (Spain)
2002-11-28
Experimental total electron scattering cross sections from Xe in the energy range 300-5000 eV have been obtained with experimental errors of about 3%. The method was based on the measurement of the attenuation of a linear electron beam through a Xe gas cell in combination with an electron spectroscopy technique to analyse the energy of the transmitted electrons. Differential and integral elastic cross sections have been calculated using a scattering potential method which includes relativistic effects. The consistency of our theoretical and experimental results is also discussed in the paper. Finally, analytical formulae depending on two parameters, namely the number of target electrons and the atomic polarizability, are given to reproduce the experimental data for Ne, Ar, Kr and Xe in the energy range 500-10 000 eV.
Phase-shift analysis of low-energy {pi}{sup +}/-p elastic-scattering data
Energy Technology Data Exchange (ETDEWEB)
Matsinos, E. [Varian Medical Systems Imaging Laboratory GmbH, Taefernstrasse 7, CH-5405 Baden-Daettwil (Switzerland)]. E-mail: evangelos.matsinos@varian.com; Woolcock, W.S. [Department of Theoretical Physics, IAS, Australian National University, Canberra, ACT 0200 (Australia); Oades, G.C. [Institute of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Rasche, G. [Institut fuer Theoretische Physik der Universitaet, Winterthurerstrasse 190, CH-8057 Zurich (Switzerland); Gashi, A. [Mediscope AG, Alfred Escher-Str. 27, CH-8002 Zurich (Switzerland)
2006-10-30
Using electromagnetic corrections previously calculated by means of a potential model, we have made a phase-shift analysis of the {pi}{sup +}/-p elastic-scattering data up to a pion laboratory kinetic energy of 100 MeV. The hadronic interaction was assumed to be isospin invariant. We found that it was possible to obtain self-consistent databases by removing very few measurements. A pion-nucleon model, based on s- and u-channel diagrams with N and {delta} in the intermediate states, and {sigma} and {rho} t-channel exchanges, was fitted to the elastic-scattering database obtained after the removal of the outliers. The model-parameter values showed an impressive stability when the database was subjected to different criteria for the rejection of experiments. Our result for the pseudovector {pi}NN coupling constant (in the standard form) is 0.0733+/-0.0014. The six hadronic phase shifts up to 100 MeV are given in tabulated form. We also give the values of the s-wave scattering lengths and the p-wave scattering volumes. Big differences in the s-wave part of the interaction were observed when comparing our hadronic phase shifts with those of the current GWU solution. We demonstrate that the hadronic phase shifts obtained from the analysis of the elastic-scattering data cannot reproduce the measurements of the {pi}{sup -}p charge-exchange reaction, thus corroborating past evidence that the hadronic interaction violates isospin invariance. Assuming the validity of the result obtained within the framework of chiral perturbation theory, that the mass difference between the u- and the d-quark has only a very small effect on the isospin invariance of the purely hadronic interaction, the isospin-invariance violation revealed by the data must arise from the fact that we are dealing with a hadronic interaction which still contains residual effects of electromagnetic origin.
Total and elastic electron scattering cross sections from ozone at intermediate and high energies
Energy Technology Data Exchange (ETDEWEB)
Pablos, J.L. de; Garcia, G. [Departamento de Fusion y Particulas Elementales, CIEMAT, Madrid (Spain); Kendall, P.A.; Mason, N.J.; Tegeder, P. [Department of Physics and Astronomy, University College London, London (United Kingdom); Williart, A. [Departamento de Fisica de los Materiales, UNED, Madrid (Spain); Blanco, F. [Departamento de Fisica Atomica Molecular y Nuclear, Universidad Complutense de Madrid, Madrid (Spain)
2002-02-28
Total cross sections for electron scattering from O{sub 3} molecules in the energy range 350-5000 eV have been measured for the first time. The experimental method used was based on the measurement of the attenuation of a collimated electron beam through an O{sub 3}-O{sub 2} mixture in combination with use of an electron energy loss technique to determine the purity of the ozone sample. Differential and integral elastic cross sections have also been calculated using a scattering potential in the framework of the independent-atom model. The present theoretical and experimental results are compared with earlier calculations available in the literature. (author)
Backward asymmetry measurements in the elastic pion-proton scattering at resonance energies
Alekseev, I. G.; Bazhanov, N. A.; Beloglazov, Yu. A.; Budkovsky, P. E.; Bunyatova, E. I.; Filimonov, E. A.; Kanavets, V. P.; Kovalev, A. I.; Koroleva, L. I.; Morozov, B. V.; Nesterov, V. M.; Novinsky, D. V.; Ryltsov, V. V.; Shchedrov, V. A.; Sulimov, A. D.
2008-01-01
The asymmetry parameter P was measured for the elastic pion-proton scattering in the very backward angular region of theta_cm ~ 150-170^o at several pion beam energies in the invariant mass range containing most of the pion-proton resonances. The general goal of the experimental program was to provide new data for partial wave analyses in order to resolve their uncertainties in the baryon resonance region to allow the unambiguous baryon spectrum reconstructions. Until recently the parameter P...
Nucleon-nucleon dynamics at medium energies (I). Unitary model for elastic and inelastic scattering
Kloet, W. M.; Silbar, Richard R.
1980-04-01
A framework is presented for a unified theory of elastic nucleon-nucleon scattering and single-pion production at medium energies. The model is relativistic, unitary, and takes into account all spin complications. In the simplest version of the theory the driving mechanism is one-pion exchange but the model can be extended to include short-range forces. The resulting set of coupled linear integral equations have the structure of three-body equations and can be solved exactly. The method of solution is discussed.
Energy Technology Data Exchange (ETDEWEB)
Gashi, A.; Matsinos, E.; Oades, G.C. E-mail: gco@ifa.au.dk; Rasche, G.; Woolcock, W.S
2001-04-09
We calculate for the s-, p{sub 1/2}- and p{sub 3/2}-waves the electromagnetic corrections which must be subtracted from the nuclear phase shifts obtained from the analysis of low-energy {pi}{sup +}p elastic scattering data, in order to obtain hadronic phase shifts. The calculation uses relativised Schroedinger equations containing the sum of an electromagnetic potential and an effective hadronic potential. We compare our results with those of previous calculations and estimate the uncertainties in the corrections.
Electromagnetic corrections to the hadronic phase shifts in low energy pi sup + p elastic scattering
Gashi, A; Oades, G C; Rasche, G; Woolcock, W S
2001-01-01
We calculate for the s-, p sub 1 sub / sub 2 - and p sub 3 sub / sub 2 -waves the electromagnetic corrections which must be subtracted from the nuclear phase shifts obtained from the analysis of low-energy pi sup + p elastic scattering data, in order to obtain hadronic phase shifts. The calculation uses relativised Schroedinger equations containing the sum of an electromagnetic potential and an effective hadronic potential. We compare our results with those of previous calculations and estimate the uncertainties in the corrections.
Tol, P.J.J.; Hogervorst, W.; Vassen, W.
2004-01-01
A model was developed to allow simulation of evaporative cooling experiments in situations where the elastic scattering cross section depends on collision energy. The model was used to simulate the number of atoms and temperature in a rf sweep for metastable helium. The value of the scattering
Resonances in low-energy electron elastic scattering from Fullerenes C60 through C92
Felfli, Zineb; Msezane, Alfred
2017-04-01
The electron affinity (EA) provides a stringent test of theory when the calculated and measured EAs are compared. A strong motivation for the fundamental investigations of low-energy electron elastic scattering from the selected fullerenes C60, C70, C74, C80, C82, C84 and C92 is the availability of high quality measured EAs. The Regge pole calculated electron elastic total cross sections for these fullerenes are found to be characterized generally by Ramsauer-Townsend (R-T) minima, shape resonances and dramatically sharp resonances manifesting stable negative ion formation. The extracted binding energies for the resultant anions agree excellently with the measured EAs of the fullerenes listed above, giving great credence to the Regge pole method and confirming that fullerenes behave like ``big atoms''. Common among all these fullerenes is the appearance of their ground state negative ions at their second R-T minima, similarly to the atomic Au case. This work was supported by U.S. DOE, Basic Energy Sciences, Office of Energy Research.
Li, Jun; Zhang, Song Bin; Ye, Bang Jiao; Wang, Jian Guo; Janev, R. K.
2017-09-01
Low-energy electron elastic scattering and impact ionization with hydrogenlike helium in Debye plasmas have been investigated by employing the exterior complex scaling method. The interactions between charged particles in the plasmas have been represented by Debye-Hückel potentials. The 1 s -1 s elastic collision strengths below the n =2 excitation threshold of He+ dominated by resonance structures are calculated for different screening lengths. As the screening strength increases, the resonance peaks studied [2(1,0) 2 +1Se,3Po,1De , and 2(0,1) 2 +1Po] exhibit blueshifts and then redshifts with a further increase of the screening strength, which results in dramatic changes of the collision strengths. It is found that these dynamic variation features of the resonances are related to the changes of energy levels of He+ in the screened potential and geometric configurations of resonances. Triple-differential-ionization cross sections in coplanar geometries at 6-Ry incident electron energy are also reported, significant changes are observed with varying screening length.
Curve crossing for low energy elastic scattering of He (plus) by Ne
Bobbio, S. M.; Doverspike, L. D.; Champion, R. L.
1972-01-01
The perturbation seen in the experimental differential elastic scattering cross section for the 40 eV He(+) + Ne system was attributed to a single crossing of two intermolecular potential energy curves. A new theoretical treatment of the curve crossing problem, that of Delos and Thorson, is employed to obtain the crossing probabilities and phases associated with the crossing. These are determined by utilizing ab initio potentials involved in the crossing and are further used in a partial wave calculation of the cross section, which is compared with our experiment. The origin of the oscillatory structure observed in the differential cross section is discussed in semiclassical terms by defining the problem in terms of two pseudo-deflection functions. A rainbow effect is shown to be related to a particular feature (a maximum rather than a minimum) of these deflection functions.
Curve crossing for low-energy elastic scattering of He/+/ by Ne.
Bobbio, S. M.; Doverspike, L. D.; Champion, R. L.
1973-01-01
The perturbation seen in the experimental differential elastic-scattering cross section for the 40-eV He/+/ + Ne system has been attributed to a single crossing of two intermolecular potential-energy curves. A new theoretical treatment of the curve-crossing problem, namely, that of Delos and Thorson, is employed to obtain the crossing probabilities and phases associated with the crossing. These are determined by utilizing ab initio potentials involved in the crossing and are further used in a partial-wave calculation of the cross section, which is compared with our experiment. The origin of the oscillatory structure observed in the differential cross section is discussed in semiclassical terms by defining the problem in terms of two pseudo-deflection-functions. A rainbow effect is shown to be related to a particular feature (a maximum rather than a minimum) of these deflection functions.
Backward asymmetry measurements in the elastic pion-proton scattering at resonance energies
Energy Technology Data Exchange (ETDEWEB)
Alekseev, I.G.; Budkovsky, P.E.; Kanavets, V.P.; Koroleva, L.I.; Morozov, B.V.; Nesterov, V.M.; Ryltsov, V.V.; Sulimov, A.D.; Svirida, D.N. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Bazhanov, N.A.; Bunyatova, E.I.; Zolin, L.S. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Beloglazov, Yu.A.; Filimonov, E.A.; Kovalev, A.I.; Novinsky, D.V.; Shchedrov, V.A.; Sumachev, V.V.; Trautman, V.Yu. [Petersburg Nuclear Physics Institute, Gatchina (Russian Federation)
2009-02-15
The asymmetry parameter P was measured for the elastic pion-proton scattering in the very backward angular region of {theta}{sub CM}{approx}150-170 at several pion beam energies in the invariant-mass range containing most of the pion-proton resonances. The general goal of the experimental program was to provide new data for partial wave analyses in order to resolve their uncertainties in the baryon resonance region to allow the unambiguous baryon spectrum reconstructions. Until recently the parameter P was not measured in the examined domain that might be explained by the extremely low cross-section. At the same time the predictions of various partial wave analyses are far from agreement in some kinematic areas and specifically those areas were chosen for the measurements where the disagreement is most pronouncing. The experiment was performed at the ITEP U-10 proton synchrotron, Moscow, by the ITEP-PNPI Collaboration in the latest 5 years. (orig.)
Backward asymmetry measurements in the elastic pion-proton scattering at resonance energies
Alekseev, I. G.; Bazhanov, N. A.; Beloglazov, Yu. A.; Budkovsky, P. E.; Bunyatova, E. I.; Filimonov, E. A.; Kanavets, V. P.; Kovalev, A. I.; Koroleva, L. I.; Morozov, B. V.; Nesterov, V. M.; Novinsky, D. V.; Ryltsov, V. V.; Shchedrov, V. A.; Sulimov, A. D.; Sumachev, V. V.; Svirida, D. N.; Trautman, V. Yu.; Zolin, L. S.
2009-02-01
The asymmetry parameter P was measured for the elastic pion-proton scattering in the very backward angular region of θ_{CM}^{} ≈ 150 - 170° at several pion beam energies in the invariant-mass range containing most of the pion-proton resonances. The general goal of the experimental program was to provide new data for partial wave analyses in order to resolve their uncertainties in the baryon resonance region to allow the unambiguous baryon spectrum reconstructions. Until recently the parameter P was not measured in the examined domain that might be explained by the extremely low cross-section. At the same time the predictions of various partial wave analyses are far from agreement in some kinematic areas and specifically those areas were chosen for the measurements where the disagreement is most pronouncing. The experiment was performed at the ITEP U-10 proton synchrotron, Moscow, by the ITEP-PNPI Collaboration in the latest 5 years.
A Precision Measurement of pp Elastic Scattering Cross Sections at Intermediate Energies
Albers, D; Bisplinghoff, J; Bollmann, R; Büsser, K; Busch, M; Daniel, R; Diehl, O; Dohrmann, F; Engelhardt, H P; Ernst, J; Eversheim, P D; Gasthuber, M; Gebel, R; Greiff, J; Gross, A; Gross-Hardt, R; Heider, S; Heine, A; Hinterberger, F; Hueskes, T; Igelbrink, M; Jeske, M; Langkau, R; Lindlein, J; Maier, R; Maschuw, R; Mosel, F; Prasuhn, D; Rohdjess, H; Rosendaal, D; Von Rossen, P; Scheid, N; Schirm, N; Schulz-Rojahn, M; Schwandt, F; Schwarz, V; Scobel, W; Thomas, S; Trelle, H J; Weise, E; Wellinghausen, A; Woller, K; Ziegler, R
2004-01-01
We have measured differential cross sections for \\pp elastic scattering with internal fiber targets in the recirculating beam of the proton synchrotron COSY. Measurements were made continuously during acceleration for projectile kinetic energies between 0.23 and 2.59 GeV in the angular range $30 \\leq \\theta_{c.m.} \\leq 90$ deg. Details of the apparatus and the data analysis are given and the resulting excitation functions and angular distributions presented. The precision of each data point is typically better than 4%, and a relative normalization uncertainty of only 2.5% within an excitation function has been reached. The impact on phase shift analysis as well as upper bounds on possible resonant contributions in lower partial waves are discussed.
Energy Technology Data Exchange (ETDEWEB)
Wielunski, L.S. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), Lindfield, NSW (Australia). Div. of Applied Physics
1996-12-31
The sensitivity of hydrogen elastic recoil detection ( ERD ) is usually limited by the low energy background in the ERD spectrum. A number of 4.5 MeV He{sup ++} hydrogen ERD spectra from different hydrogen implanted samples are compared. The samples are chosen with different atomic numbers from low Z (carbon) to high Z (tungsten carbide) to observe the effects of multiple scattering and double scattering within the sample material. The experimental depth resolution and levels of the low energy background in ERD spectra are compared with theoretical predictions from multiple and double scattering. 10 refs., 2 tabs., 5 figs.
The 106Cd(alpha,alpha)106Cd elastic scattering in a wide energy range for gamma-process studies
Ornelas, A.; Kiss, G.G.(Institute for Nuclear Research (MTA ATOMKI), Debrecen, H-4001, Hungary); Mohr, P; Galaviz, D.; Fülöp, Zs.; Gyürky, Gy.(Institute for Nuclear Research (MTA ATOMKI), Debrecen, H-4001, Hungary); Máté, Z.; Rauscher, T.; Somorjai, E.; Sonnabend, K.; Zilges, A.
2015-01-01
Alpha elastic scattering angular distributions of the 106Cd(alpha,alpha)106Cd reaction were measured at three energies around the Coulomb barrier to provide a sensitive test for the alpha + nucleus optical potential parameter sets. Furthermore, the new high precision angular distributions, together with the data available from the literature were used to study the energy dependence of the locally optimized {\\alpha}+nucleus optical potential in a wide energy region ranging from E_Lab = 27.0 Me...
DEFF Research Database (Denmark)
Langbein, Wolfgang Werner; Hvam, Jørn Märcher
2002-01-01
for increasing time after excitation, giving direct evidence for the time-energy uncertainty in the dynamics of the scattering by disorder. The ring width converges with time to a finite value, a direct measure of an intrinsic momentum broadening of the polariton states localized by multiple disorder scattering....
Energy Technology Data Exchange (ETDEWEB)
Morcelle, V.; Lichtenthaeler, R.; Guimaraes, V.; Lepine-Szily, A.; Faria, P.N.; Camargo, O.; Barioni, A.; Mendes Junior, D.R.; Condori, R.P.; Zamora, J.C.; Morais, M.C.; Pires, K.C.C.; Scarduelli, V.; Leistenschneider, E.; Zagatto, V.A.B. [Universidade de Sao Paulo (USP), SP (Brazil); Shorto, J.M.B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)
2011-07-01
Full text: Elastic scattering angular distributions and total reaction cross sections of the neutron halo projectile nucleus {sup 6}He on a {sup 58}Ni target at energies around the Coulomb barrier are presented. The measurements were obtained at pelletron accelerator at the University of Sao Paulo (Brazil) and the {sup 6}He radioactive secondary beam has been produced in the RIBRAS system through the {sup 9}Be({sup 7}Li, {sup 6}He){sup 10}B production reaction. The elastic scattering angular distributions obtained at E{sub Lab}= 12.5, 16.5 and 21.0 MeV, have been analysed by using optical model, using the Sao Paulo and Wood-Saxon potentials and the respective total reaction cross sections have been obtained. The total reaction cross sections have been reduced using the Wong formula and the UFF equation and are compared with other stable and unstable systems from the literature. (author)
Low energy o-Ps-o-Ps elastic scattering using a simple model
Energy Technology Data Exchange (ETDEWEB)
Himanshu, Sharma [Veer Kunwar Singh Univ., Dept. of Physics, Bihar (India); Kiran, Kumari [R N College, P. G. Dept. of Physics, Bihar (India); Sumana, Chakraborty [Indian Association for the Cultivation of Science, Dept. of Theoretical Physics (India)
2009-06-15
A simple model is employed to investigate o-Ps-o-Ps (positronium-positronium) scattering at low energies. This model contains the effect of exchange explicitly and a model long range potential in the framework of static-exchange model. These two physical features are of key importance in Ps-Ps (atom-atom) scattering system. S-wave triplet-triplet and singlet-singlet scattering lengths and corresponding phase shifts up to the incident momentum k = 0.5 a.u. are in excellent agreement with those yielded by most elaborate and theoretically sound predictions. (authors)
Study of the elastic scattering of {sup 6}He on {sup 208}Pb at energies around the Coulomb barrier
Energy Technology Data Exchange (ETDEWEB)
Sanchez-Benitez, A.M. [Departamento de Fisica Aplicada, Universidad de Huelva, E-21071 Huelva (Spain); Centre de Recherches du Cyclotron, Universite Catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Escrig, D. [Instituto de Estructura de la Materia, CSIC, E-28006 Madrid (Spain); Alvarez, M.A.G.; Andres, M.V. [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, E-41080 Sevilla (Spain); Angulo, C. [Centre de Recherches du Cyclotron, Universite Catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Borge, M.J.G. [Instituto de Estructura de la Materia, CSIC, E-28006 Madrid (Spain); Cabrera, J. [Centre de Recherches du Cyclotron, Universite Catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Cherubini, S. [INFN Laboratori Nazionali del Sud, I-95123 Catania (Italy); Demaret, P. [Centre de Recherches du Cyclotron, Universite Catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Espino, J.M. [Dept. de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, E-41080 Sevilla (Spain); Figuera, P. [INFN Laboratori Nazionali del Sud, I-95123 Catania (Italy); Freer, M. [School of Physics and Astronomy, University of Birmingham, B15 2TT Birmingham (United Kingdom); Garcia-Ramos, J.E. [Departamento de Fisica Aplicada, Universidad de Huelva, E-21071 Huelva (Spain); Gomez-Camacho, J. [Dept. de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, E-41080 Sevilla (Spain); Gulino, M. [INFN Laboratori Nazionali del Sud, I-95123 Catania (Italy); Kakuee, O.R. [Van der Graaff Laboratory, Nuclear Research Centre, AEOI, PO Box 14155-1339, Tehran (Iran, Islamic Republic of); Martel, I. [Dept. de Fisica Aplicada, Universidad de Huelva, E-21071 Huelva (Spain)], E-mail: imartel@uhu.es; Metelko, C. [School of Physics and Astronomy, University of Birmingham, B15 2TT Birmingham (United Kingdom); Moro, A.M. [Dept. de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, E-41080 Sevilla (Spain)] (and others)
2008-04-15
The elastic scattering of {sup 6}He on {sup 208}Pb has been measured at laboratory energies of 14, 16, 18 and 22 MeV. These data were analyzed using phenomenological Woods-Saxon form factors and optical model calculations. A semiclassical polarization potential was used to study the effect of the Coulomb dipole polarizability. Evidence for long range absorption, partially arising from Coulomb dipole polarizability, is reported. The energy variation of the optical potential was found to be consistent with the dispersion relations which connect the real and imaginary parts of the potential.
Xu, Hai-Bo; Zheng, Na
2015-07-01
A version of Geant4 has been developed to treat high-energy proton radiography. This article presents the results of calculations simulating the effects of nuclear elastic scattering for various test step wedges. Comparisons with experimental data are also presented. The traditional expressions of the transmission should be correct if the angle distribution of the scattering is Gaussian multiple Coulomb scattering. The mean free path (which depends on the collimator angle) and the radiation length are treated as empirical parameters, according to transmission as a function of thickness obtained by simulations. The results can be used in density reconstruction, which depends on the transmission expressions. Supported by NSAF (11176001) and Science and Technology Developing Foundation of China Academy of Engineering Physics (2012A0202006)
Simulation of 12C+12C elastic scattering at high energy by using the Monte Carlo method
Guo, Chen-Lei; Zhang, Gao-Long; Tanihata, I.; Le, Xiao-Yun
2012-03-01
The Monte Carlo method is used to simulate the 12C+12C reaction process. Taking into account the size of the incident 12C beam spot and the thickness of the 12C target, the distributions of scattered 12C on the MWPC and the CsI detectors at a detective distance have been simulated. In order to separate elastic scattering from the inelastic scattering with 4.4 MeV excited energy, we set several variables: the kinetic energy of incident 12C, the thickness of the 12C target, the ratio of the excited state, the wire spacing of the MWPC, the energy resolution of the CsI detector and the time resolution of the plastic scintillator. From the simulation results, the preliminary establishment of the experiment system can be determined to be that the beam size of the incident 12C is phi5 mm, the incident kinetic energy is 200-400 A MeV, the target thickness is 2 mm, the ratio of the excited state is 20%, the flight distance of scattered 12C is 3 m, the energy resolution of the CsI detectors is 1%, the time resolution of the plastic scintillator is 0.5%, and the size of the CsI detectors is 7 cm×7 cm, and we need at least 16 CsI detectors to cover a 0° to 5° angular distribution.
Energy Technology Data Exchange (ETDEWEB)
Hinterberger, F.; Rohdjess, H.; Altmeier, M.; Bauer, F.; Bisplinghoff, J.; Buesser, K.; Busch, M.; Colberg, T.; Diehl, O.; Dohrmann, F.; Engelhardt, H.P.; Eversheim, P.D.; Felden, O.; Gebel, R.; Glende, M.; Greiff, J.; Gross-Hardt, R.; Jahn, R.; Jonas, E.; Krause, H.; Langkau, R.; Lindemann, T.; Lindlein, J.; Maier, R.; Maschuw, R.; Mayer-Kuckuk, T.; Meinerzhagen, A.; Naehle, O.; Prasuhn, D.; Rosendaal, D.; Rossen, P. von; Schirm, N.; Schulz-Rojahn, M.; Schwarz, V.; Scobel, W.; Trelle, H.J.; Weise, E.; Wellinghausen, A.; Woller, K.; Ziegler, R
2000-01-31
The EDDA experiment at the cooler synchrotron COSY measures proton-proton elastic scattering excitation functions in the momentum range 0.8 - 3.4 GeV/c. In phase 1 of the experiment, spin-averaged differential cross sections were measured continuously during acceleration with an internal polypropylene (CH{sub 2}) fiber target, taking particular care to monitor luminosity as a function of beam momentum. In phase 2, excitation functions of the analyzing power A{sub N} and the polarization correlation parameters A{sub NN}, A{sub SS} and A{sub SL} are measured using a polarized proton beam and a polarized atomic hydrogen beam target. The paper presents recent d{sigma}/d{omega} and A{sub N} data. The results provide excitation functions and angular distributions of high precision and internal consistency. No evidence for narrow structures was found. The data are compared to recent phase shift solutions.
Hinterberger, F.; Rohdjeß, H.; Altmeier, M.; Bauer, F.; Bisplinghoff, J.; Büßer, K.; Busch, M.; Colberg, T.; Diehl, O.; Dohrmann, F.; Engelhardt, H. P.; Eversheim, P. D.; Felden, O.; Gebel, R.; Glende, M.; Greiff, J.; Groß-Hardt, R.; Hinterberger, F.; Jahn, R.; Jonas, E.; Krause, H.; Langkau, R.; Lindemann, T.; Lindlein, J.; Maier, R.; Maschuw, R.; Mayer-Kuckuk, T.; Meinerzhagen, A.; Nähle, O.; Prasuhn, D.; Rohdjeß, H.; Rosendaal, D.; von Rossen, P.; Schirm, N.; Schulz-Rojahn, M.; Schwarz, V.; Scobel, W.; Trelle, H. J.; Weise, E.; Wellinghausen, A.; Woller, K.; Ziegler, R.
2000-01-01
The EDDA experiment at the cooler synchrotron COSY measures proton-proton elastic scattering excitation functions in the momentum range 0.8 - 3.4 GeV/c. In phase 1 of the experiment, spin-averaged differential cross sections were measured continuously during acceleration with an internal polypropylene (CH2) fiber target, taking particular care to monitor luminosity as a function of beam momentum. In phase 2, excitation functions of the analyzing power AN and the polarization correlation parameters ANN, ASS and ASL are measured using a polarized proton beam and a polarized atomic hydrogen beam target. The paper presents recent dσ/dΩ and AN data. The results provide excitation functions and angular distributions of high precision and internal consistency. No evidence for narrow structures was found. The data are compared to recent phase shift solutions.
Hinterberger, F; Altmeier, M; Bauer, F; Bisplinghoff, J; Büsser, K; Busch, M; Colberg, T; Diehl, O; Dohrmann, F; Engelhardt, H P; Eversheim, P D; Felden, O; Gebel, R; Glende, M; Greiff, J; Gross-Hardt, R; Hinterberger, F; Jahn, R; Jonas, E; Krause, H; Langkau, R; Lindemann, T; Lindlein, J; Maier, R; Maschuw, R; Mayer-Kuckuk, T; Meinerzhagen, A; Naehle, O; Prasuhn, D; Rohdjess, H; Rosendaal, D; Von Rossen, P; Schirm, N; Schulz-Rojahn, M; Schwarz, V; Scobel, W; Trelle, H J; Weise, E; Wellinghausen, A; Woller, K; Ziegler, R
2000-01-01
The EDDA experiment at the cooler synchrotron COSY measures proton-proton elastic scattering excitation functions in the momentum range 0.8 - 3.4 GeV/c. In phase 1 of the experiment, spin-averaged differential cross sections were measured continuously during acceleration with an internal polypropylene (CH sub 2) fiber target, taking particular care to monitor luminosity as a function of beam momentum. In phase 2, excitation functions of the analyzing power A sub N and the polarization correlation parameters A sub N sub N , A sub S sub S and A sub S sub L are measured using a polarized proton beam and a polarized atomic hydrogen beam target. The paper presents recent d sigma/d OMEGA and A sub N data. The results provide excitation functions and angular distributions of high precision and internal consistency. No evidence for narrow structures was found. The data are compared to recent phase shift solutions.
Energy Technology Data Exchange (ETDEWEB)
Farag, M.Y.H.; Esmael, E.H. [Cairo University, Physics Department, Faculty of Science, Giza (Egypt); Maridi, H.M. [Cairo University, Physics Department, Faculty of Science, Giza (Egypt); Taiz University, Physics Department, Faculty of Applied Science, Taiz (Yemen)
2012-11-15
The proton elastic scattering data on some light exotic nuclei, namely, {sup 6,} {sup 8}He, {sup 9,} {sup 11}Li, and {sup 10,} {sup 11,} {sup 12}Be, at energies below than 100MeV/nucleon are analyzed using the single folding optical model. The real, imaginary, and spin-orbit parts of the optical potential (OP) are constructed only from the folded potentials and their derivatives using M3Y effective nucleon-nucleon interaction. These OP parts, their renormalization factors and their volume integrals are studied. The surface and spin-orbit potentials are important to fit the experimental data. Three model densities for halo nuclei are used and the sensitivity of the cross-sections to these densities is tested. The imaginary OP within high-energy approximation is used and compared with the single folding OP. This OP with few and limited fitting parameters, which have systematic behavior with incident energy, successfully describes the proton elastic scattering data with exotic nuclei. (orig.)
Luminosity calibration from elastic scattering
Stenzel, H
2006-01-01
The absolute luminosity of the LHC at the ATLAS interaction point will be calibrated by the measurement of the t-distribution of elastic pp-scattering in the Coulomb-Nuclear interference region. The ALFA detector housed in Roman Pots located 240m away from IP1 is designed to approach the beam at mm distance and to measure elastic pp-scattering at micro-radian scattering angles. This measurement will be performed with dedicated runs using a special beam optics with high beta* and parallel-to-point focusing in order to access the Coulomb regime. In this note the expected performance of this method, evaluated with a simulation of the experimental set-up, is presented.
Energy Technology Data Exchange (ETDEWEB)
Gauron, Pierre; Basarab Nicolescu [Theoretical Physics Division, Inst. de Physique Nucleaire, Paris-11 Univ., 91 - Orsay (France); Leader Elliot [Birkbeck College, Malet Street, London WCIE 7HX (United Kingdom)
1999-10-01
We generalize a relation proposed recently by Giffon, Predazzi and Samokhin, linked to the behaviour of elastic scattering at asymptotically high energies. We demonstrate that their result, established within a limited class of possible asymptotic behaviour, is actually very general and can be proved in an essentially axiomatic framework. We discuss how this relation can be used as a basis for detecting new phenomena at RHIC and LHC energies. (authors)
Excitation functions of proton-proton elastic scattering at intermediate energies
Scobel, W.; Dohrmann, F.; Bisplinghoff, J.; Hinterberger, F.; Scobel, W.; Altmeier, M.; Bauer, F.; Bisplinghoff, J.; Bissel, T.; Bollmann, R.; Busch, M.; Büßer, K.; Cloth, P.; Danie, R.; Diehl, O.; Dohrmann, F.; Engelhardt, H. P.; Ernst, J.; Eversheim, P. D.; Felden, O.; Flammer, J.; Gasthuber, M.; Gebel, R.; Greiff, J.; Groß, A.; Groß-Hardt, R.; Hebbel, K.; Hinterberger, F.; Hüskes, T.; Jahn, R.; Koch, I.; Langkau, R.; Lindemann, T.; Lindlein, J.; Maier, R.; Maschuw, R.; Mayer-Kuckuk, T.; Pfuff, M.; Prasuhn, D.; Rohdjeß, H.; Rosendaal, D.; von Rossen, P.; Schirm, N.; Schulz-Rojahn, M.; Schwarz, V.; Scobel, W.; Steinbeck, S.; Sterzenbach, G.; Thomas, S.; Trelle, H. J.; Walker, M.; Weise, E.; Wellinghausen, A.; Woller, K.; Ziegler, R.; EDDA Collaboration at COSY; EDDA Collaboration
1998-03-01
Excitation functions of proton-proton elastic cross sections have been measured in narrow momentum steps Δp = 28 MeV/c in the kinetic energy range from 0.5 to 2.5 GeV and the angular range 35° ≤ Θcm ≤ 90° with a detector providing ΔΘcm ≈ 1.4° resolution and 82% solid angle coverage. Measurements have been performed continuously during projectile acceleration in the Cooler Synchrotron COSY with an internal CH 2 fiber target; background corrections were derived from measurements with a carbon fiber target and from Monte Carlo simulations of inelastic pp contributions. Particular care was taken to monitor the luminosity as a function of beam energy. The results provide excitation functions and angular distributions of unprecedented precision and internal consistency. The measured cross sections are compared to recent phase shift analyses, and their impact on the present solution SM97 [1] is discussed.
Barrier distributions from elastic scattering
Energy Technology Data Exchange (ETDEWEB)
Rowley, N. [Manchester Univ. (United Kingdom). Dept. of Physics]|[Surrey Univ., Guildford (United Kingdom). Dept. of Physics; Timmers, H.; Leigh, J.R.; Masgupta, M.; Hinde, D.J.; Mein, J.C.; Morton, C.R.; Newton, J.O. [Australian National Univ., Canberra, ACT (Australia). Dept. of Nuclear Physics
1996-01-01
A new representation of the distribution of potential barriers present in heavy ion reactions is defined in terms of the elastic scattering excitation function. Its validity is demonstrated for the systems {sup 16}0 + {sup 144,} {sup 154}Sm, {sup 186}W, {sup 208}Pb, for which precise measurements have been made. Compared with fusion barrier distributions, which show structures characteristic of collective inelastic couplings, the elastic distributions are less detailed. This appears to be due to couplings to weaker direct reaction channels. 20 refs., 3 figs.
Electron Elastic-Scattering Cross-Section Database
SRD 64 NIST Electron Elastic-Scattering Cross-Section Database (PC database, no charge) This database provides values of differential elastic-scattering cross sections, corresponding total elastic-scattering cross sections, phase shifts, and transport cross sections for elements with atomic numbers from 1 to 96 and for electron energies between 50 eV and 20,000 eV (in steps of 1 eV).
Analyses of Alpha-Alpha Elastic Scattering Data in the Energy Range 140 - 280 MeV
Energy Technology Data Exchange (ETDEWEB)
Shehadeh, Zuhair F. [Taif University, Taif (Saudi Arabia)
2017-01-15
The differential and the reaction cross-sections for 4He-4He elastic scattering data have been nicely obtained at four energies ranging from 140 MeV to 280 MeV (lab system), namely, 140, 160, 198 and 280 MeV, by using a new optical potential with a short-range repulsive core. The treatment has been handled relativistically as υ/c > 0.25 for the two lower energies and υ/c > 0.31 for the two higher ones. In addition to explaining the elastic angular distributions, the adopted potentials accounted for the structure that may exist at angles close to 90◦ , especially for the 198 and the 280-MeV incident energies. No renormalization has been used, and all our potential parameters are new. The necessity of including a short-range repulsive potential term in our real nuclear potential part has been demonstrated. Our results contribute to solving a long-standing problem concerning the nature of the alpha-alpha potential. This is very beneficial in explaining unknown alpha-nucleus and nucleus-nucleus relativistic reactions by using the cluster formalism.
Directory of Open Access Journals (Sweden)
Fried H. M.
2016-01-01
Full Text Available A new non-perturbative, gauge-invariant model QCD renormalization is applied to high energy elastic pp-scattering. The differential cross-section deduced from this model displays a diffraction dip that resembles those of experiments. Comparison with ISR and LHC data is currently underway.
Electron elastic scattering off endo-fullerenes
Dolmatov, Valeriy
2017-04-01
The given presentation highlights the physically transparent, relatively simple, and yet reasonably complete approximation to the problem of low-energy electron elastic scattering off endohedral fullerenes A@CN along with corresponding findings unraveled on its basis. It is believed that, as of today, the highlighted results provide the most complete information about features of e + A @CN elastic scattering brought about by the fullerene-cage-related, correlation-related, and polarization-related impacts of the individual and coupled members of the A@C60 target on the scattering process. Each of the impacts is shown to bring spectacular features into e + A @C60 scattering. A remarkable inherent quality of the developed approximation is its ability to account for mutual coupling between electronic excited configurations of CN with those of the encapsulated atom A without reference to complicated details of the electronic structure of CN itself. Spectacular effects in the scattering process, primarily associated with polarization of A@C60 by an incident electron, are thoughtfully detailed both quantitatively and qualitatively in a physically transparent manner for ease of understanding and convenience of the audience. This study was performed in collaboration with Professors M. Ya. Amusia, L. V. Chernysheva, and UNA undergraduate students. The past support by the NSF Grant PHY-1305085 is acknowledged.
Calculation of vector analyzing power in the p+6,8He elastic scattering at intermediate energies
Directory of Open Access Journals (Sweden)
Ibraeva Elena
2014-03-01
Full Text Available A calculations of the analyzing power (Ay of the elastic proton scattering on 6He and 8He are presented in the framework of the Glauber multiple diffraction scattering at E = 71 and 1000 MeV/nucleon. The wave functions obtained in the three-body α-n-n-model for 6He and the density distribution function in the no-core shell model for 8He are used. Our calculations qualitatively reproduced the data of Ay for p6He and p8He scattering and compare with the calculations’ results in the other approaches.
Directory of Open Access Journals (Sweden)
Farag M. Y. H.
2014-03-01
Full Text Available The proton elastic scattering data on 4,6,8 He and 6,7,9,11Li nuclei at energies below 160 MeV/nucleon are analyzed using the optical model. The optical potential (OP is taken microscopically, with few and limited fitting parameters, using the single folding model for the real part and high-energy approximation (HEA for the imaginary one. Clear dependencies of the volume integrals on energy and rms radii are obtained from the results. The calculated differential and the reaction cross sections are in good agreement with the available experimental data. In general, this OP with few and limited fitting parameters, which have a systematic behavior with incident energy and matter radii, successfully describes the proton elastic scattering data with stable and exotic light nuclei at energies up to 160 MeV/nucleon.
Light Scattering Spectroscopy: From Elastic to Inelastic
Perelman, Lev T.; Modell, Mark D.; Vitkin, Edward; Hanlon, Eugene B.
This chapter reviews light scattering spectroscopic techniques in which coherent effects are critical because they define the structure of the spectrum. In the case of elastic light scattering spectroscopy, the targets themselves, such as aerosol particles in environmental science or cells and subcellular organelles in biomedical applications, play the role of microscopic optical resonators. In the case of inelastic light scattering spectroscopy or Raman spectroscopy, the spectrum is created due to light scattering from vibrations in molecules or optical phonons in solids. We will show that light scattering spectroscopic techniques, both elastic and inelastic, are emerging as very useful tools in material and environmental science and in biomedicine.
Forward elastic scattering above the physical threshold
Energy Technology Data Exchange (ETDEWEB)
Avila, R.F. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Matematica, Estatistica e Computacao Cientifica; Menon, M.J. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Fisica Gleb Wataghin
2006-07-01
Making use of the 'extended derivative dispersion relations', recently introduced by Avila and Menon, we analyze forward elastic proton-proton and antiproton-proton scattering at any energy above the physical threshold ({radical}s=2m{sub p} {approx} 1,88 GeV). The analysis is based on an analytical parametrization for the total cross section with leading triple pole pomeron (high energies) and full nondegenerated secondary reggeons (intermediate and low energies). Experimental data on total cross section and the ratio r between the real and imaginary parts of the forward amplitude are simultaneously fitted with the CERN-Minuit code and energy cutoff at 4 GeV. We show that, the results are exactly the same as those obtained through standard integral dispersion relations. Physical implications of the results in the pomeron-reggeon context are also discussed. (author)
Gabel, Frank; Bellissent-Funel, Marie-Claire
2007-01-01
We present a study of C-phycocyanin hydration water dynamics in the presence of trehalose by incoherent elastic neutron scattering. By combining data from two backscattering spectrometers with a 10-fold difference in energy resolution we extract a scattering law S(Q,ω) from the Q-dependence of the elastic intensities without sampling the quasielastic range. The hydration water is described by two dynamically different populations—one diffusing inside a sphere and the other diffusing quasifreely—with a population ratio that depends on temperature. The scattering law derived describes the experimental data from both instruments excellently over a large temperature range (235–320 K). The effective diffusion coefficient extracted is reduced by a factor of 10–15 with respect to bulk water at corresponding temperatures. Our approach demonstrates the benefits and the efficiency of using different energy resolutions in incoherent elastic neutron scattering over a large angular range for the study of biological macromolecules and hydration water. PMID:17350998
Proton-proton elastic scattering at the LHC energy of $\\sqrt{s}$ = 7 TeV
INSPIRE-00062364; Aspell, P.; Atanassov, I.; Avati, V.; Baechler, J.; Berardi, V.; Berretti, M.; Bozzo, M.; Brucken, E.; Buzzo, A.; Cafagna, F.S.; Calicchio, M.; Catanesi, M.G.; Covault, C.; Csanad, M.; Csorgo, T.; Deile, M.; Dimovasili, E.; Doubek, M.; Eggert, K.; Eremin, V.; Ferro, F.; Fiergolski, A.; Garcia, F.; Giani, S.; Greco, V.; Grzanka, L.; Heino, J.; Hilden, T.; Janda, M.; Kaspar, J.; Kopal, J.; Kundrat, V.; Kurvinen, K.; Lami, S.; Latino, G.; Lauhakangas, R.; Leszko, T.; Lippmaa, E.; Lokajicek, M.; Lo Vetere, M.; Lucas Rodriguez, F.; Macri, M.; Magaletti, L.; Magazzu, G.; Mercadante, A.; Minutoli, S.; Nemes, F.; Niewiadomski, H.; Noschis, E.; Novak, T.; Oliveri, E.; Oljemark, F.; Orava, R.; Oriunno, M.; Osterberg, K.; Perrot, A.L.; Palazzi, P.; Pedreschi, E.; Petajajarvi, J.; Prochazka, J.; Quinto, M.; Radermacher, E.; Radicioni, E.; Ravotti, F.; Robutti, E.; Ropelewski, L.; Ruggiero, G.; Saarikko, H.; Santroni, A.; Scribano, A.; Sette, G.; Snoeys, W.; Spinella, F.; Sziklai, J.; Taylor, C.; Turini, N.; Vacek, V.; Vitek, M.; Welti, J.; Whitmore, J.
2011-01-01
Proton-proton elastic scattering has been measured by the TOTEM experiment at the CERN Large Hadron Collider at √ s = 7 TeV in dedicated runs with the Roman Pot detectors placed as close as seven times the transverse beam size (σbeam) from the outgoing beams. After careful study of the accelerator optics and the detector alignment, |t| , the square of four-momentum transferred in the elastic scattering process, has been determined with an uncertainty of δ t = 0.1 GeV √ |t|. In this letter the first results of the differential cross section are presented covering a |t|-range from 0.36 to 2.5 GeV**2. The differential cross-section in the range 0.36 < |t| < 0.47 GeV**2 is described by an exponential with a slope parameter B = (23.6±0.5stat ±0.4syst)GeV**−2, followed by a significant diffractive minimum at |t| = (0.53±0.01stat±0.01syst)GeV**2. For |t|-values larger than ∼ 1:5GeV**2, the cross-section exhibits a power law behaviour with an exponent of -7.8 ± 0.3stat ±0.1syst. When compared to...
Coulomb correction to elastic. alpha. -. alpha. scattering
Energy Technology Data Exchange (ETDEWEB)
Bera, P.K.; Jana, A.K.; Haque, N.; Talukdar, B. (Department of Physics, Visva-Bharati University, Santiniketan-731235, West Bengal, India (IN))
1991-02-01
The elastic {alpha}-{alpha} scattering is treated within the framework of a generalized phase-function method (GPFM). This generalization consists in absorbing the effect of Coulomb interaction in the comparison functions for developing the phase equation. Based on values of scattering phase shifts computed by the present method, it is concluded that the GPFM provides an uncomplicated approach to rigorous Coulomb correction in the {alpha}-{alpha} scattering.
Energy Technology Data Exchange (ETDEWEB)
Brice, S. J. [Fermilab; Cooper, R. L. [Indiana U.; DeJongh, F. [Fermilab; Empl, A. [Houston U.; Garrison, L. M. [Indiana U.; Hime, A. [Los Alamos; Hungerford, E. [Houston U.; Kobilarcik, T. [Fermilab; Loer, B. [Fermilab; Mariani, C. [Virginia Tech.; Mocko, M. [Los Alamos; Muhrer, G. [Los Alamos; Pattie, R. [North Carolina State U.; Pavlovic, Z. [Los Alamos; Ramberg, E. [Fermilab; Scholberg, K. [Duke U.; Tayloe, R. [Indiana U.; Thornton, R. T. [Indiana U.; Yoo, J. [Fermilab; Young, A. [North Carolina State U.
2014-04-03
We present an experimental method for measuring the process of coherent elastic neutrino-nucleus scattering (CENNS). This method uses a detector situated transverse to a high-energy neutrino beam production target. This detector would be sensitive to the low-energy neutrinos arising from decay-at-rest pions in the target. We discuss the physics motivation for making this measurement and outline the predicted backgrounds and sensitivities using this approach. We report a measurement of neutron backgrounds as found in an off-axis surface location of the Fermilab Booster Neutrino Beam (BNB) target. The results indicate that the Fermilab BNB target is a favorable location for a CENNS experiment.
Neutron elastic scattering at very small angles
2002-01-01
This experiment will measure neutron-proton elastic scattering at very small angles and hence very small four-momentum transfer, |t|. The range of |t| depends on the incident neutron momentum of the events but the geometrical acceptance will cover the angular range 0.025 < $\\Theta_{lab}$ < 1.9 mrad. The higher figure could be extended to 8.4 mrad by changing the geometry of the experiment in a later phase. \\\\ \\\\ The neutron beam will be highly collimated and will be derived from a 400 GeV external proton beam of up to $4 \\times 10^{10}$ protons per pulse in the SPS North Area Hall 1. The hydrogen target will be gaseous, operating at 40 atm. pressure and acts as a multiwire proportional chamber to detect the recoil protons. The forward neutron will be detected and located by interaction in a neutron vertex detector and its energy measured by a conventional steel plate calorimeter. \\\\ \\\\ The experiment will cover the angular region of nucleon-nucleon scattering which is dominated by Coulomb scattering ...
Energy Technology Data Exchange (ETDEWEB)
Morcelle, Viviane; Gomes, P.R.S.; Lubian, J.; Mendes Junior, D.R. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil); Lichtenthaeler, R.; Guimaraes, V.; Lepine-Szily, A.; Camargo, O.; Faria, P.N. de; Gasquez, L.; Morais, M.C.; Condori, R.P.; Pires, K.C.C.; Scarduelli, V. [Universidade de Sao Paulo (USP), SP (Brazil); Barioni, A. [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil); Shorto, J.M.B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Zamora, J.C. [Technische Universitaet Darmstadt (Germany); Aguilera, E.; Martinez-Quiroz, E. [Instituto Nacional de Investigaciones Nucleares (Mexico); Kolata, J.; Jiang, H. [University of Notre Dame, IN (United States); Bechetti, F.D.; Lamm, L.O. [Michigan University, MI (United States); Lizcano, D. [Universidad Autonoma del Estado de Mexico (Mexico)
2012-07-01
Full text: Elastic scattering measurements were performed at energies around the Coulomb barrier at the Tandem Accelerators of the Sao Paulo (USP - Brazil ) and Notre Dame (UND - USA) Universities. The {sup 7}Be is a radioactive nucleus and has been produced by the reaction {sup 6}He({sup 6}Li,{sup 9}Be) and impinged on {sup 27}Al and {sup 197}Au secondary targets using a double superconducting systems RIBRAS ( USP ) and Twinsol (UND). The elastic scattering angular distributions were analyzed through the optical model calculations, using the Woods- Saxon form factors [1] and the Sao Paulo potential [2] to fit the experimental data. The total reaction cross sections were also derived and compared with others presented at the literature for other systems. In addition, a study of the nuclear potential energy dependence has been carried out in this work in the dispersion relation context. Due to the fact that {sup 7}Be has a small breakup threshold energy, the results can provide significant information of the influence of the breakup channel on the reactions involving this projectile. For this purpose, {chi}{sup 2}- data analysis with different kind of potentials were performed to identify the energy dependence of the real (V) and imaginary (W) parts of the potential. [1] L.C. Chamon et al., Phys. Rev. C 66, (2002) 014610. [2] R.D. Wood e D.S. Saxon, Phys. Rev. 95 ( 1954) 577. (author)
Differential elastic scattering of CCl/sub 4/ by Kr
Energy Technology Data Exchange (ETDEWEB)
Bobbio, S.M.; Sherrod, W.D.
1979-02-15
The differential elastic scattering cross section for CCl/sub 4/+Kr at 0.0857 eV collision energy has been measured. The experimental result resolves the low frequency rainbow structure and has been interpreted using the semiquantal method. An intermolecular potential has been recovered from the calculation and is discussed.
Double folding model analysis of elastic scattering of halo nucleus ...
Indian Academy of Sciences (India)
features of halo nuclei largely affect the interaction with light and heavy targets at low bombarding energies and have created tremendous interest in the study of nuclear reac- tions. Elastic scattering is sensitive to the nature of the surface of nuclei and hence it is effective in studying halo nuclei. Pramana – J. Phys., Vol.
Elastic scattering of electrons from Rb, Cs and Fr atoms
Gangwar, R. K.; Tripathi, A. N.; Sharma, L.; Srivastava, R.
2010-04-01
Differential, integrated elastic, momentum-transfer and total cross sections as well as differential S, T and U spin parameters for scattering of electrons from rubidium, caesium and francium atoms in the incident energy range up to 300 eV are calculated using a relativistic Dirac equation. The projectile electron-target atom interaction is represented by both real and complex parameter-free optical potentials for obtaining the solution of a Dirac equation for scattered electrons. The Dirac-Fock wavefunctions have been used to represent the Rb, Cs and Fr target atoms. The results of differential cross sections and spin asymmetry parameter S for e-Rb and e-Cs have been compared with the available experimental and theoretical results. Detailed results are reported for the elastic scattering of electrons from the ground states of a francium atom for the first time in the wide range of incident electron energies. The results of electron-Fr elastic scattering show the similar features to those obtained in the case of e-Rb and e-Cs elastic scattering.
Energy Technology Data Exchange (ETDEWEB)
Kabir, Al Amin [Kent State Univ., Kent, OH (United States)
2015-12-01
Analysis of high-energy electron scattering has been used to determine the charge radii of nuclei for several decades. Recent analysis of the Lamb shift in muonic hydrogen found an r.m.s. radius significantly different than the electron scattering result. To understand this puzzle we have analyzed the "LEDEX" data for the (e, e'p) reaction. This experiment includes measurements on several light nuclei, hydrogen, deuterium, lithium, boron, and carbon. To test our ability to measure absolute cross sections, as well as our ability to extract the charge radius, we tested our technique against the extremely well-measured carbon case and found excellent agreement using the Fourier-Bessel parametrization. We then extended the procedure to boron and lithium, which show nice agreement with the latest theoretical calculations. For hydrogen, we see clearly the limits of this technique and therefore, the charge radius is determined from the traditional extrapolation to q^{2} = 0. We will show that there is a model dependence in extracting the charge radius of hydrogen and its unambiguous determination is very difficult with available electron-scattering measurements.
Energy Technology Data Exchange (ETDEWEB)
Martini, Alvaro Favinha
1995-12-31
The proton-proton elastic scattering in the center of mass energy region 23 to 63 GeV is investigated through a multiple diffraction model. As an introduction to the subject, a detailed review of the fundamental basis of the Multiple Diffraction Formalism and a survey of the multiple diffraction models (geometrical) currently used are presented. The goal of this investigation is to reformulate one of these models, which makes use of an elementary (parton-parton) amplitude purely imaginary and is not able to predict the {rho}-parameter (the ratio of the forward real and imaginary parts of the hadronic amplitude). Introducing a real part for the elementary amplitude proportional to the imaginary part, improvements in the formalism are obtained. It is shown that this new approach is able to reproduce all experimental data on differential and integrated cross sections (total, elastic and inelastic), but not the {rho}-parameter as function of the energy. Then, starting from fitting of this parameter an overall reproduction of the physical observables is obtained, with the exception of the dip region (diffractive minimum in the differential cross section) overall description are also not firmly reached in all these models. Finally, alternatives to improve the results in a future research are suggested and discussed. (author) 69 refs., 69 figs., 20 tabs.
Elastic scattering of positrons off rare-gas atoms
Energy Technology Data Exchange (ETDEWEB)
Bhattacharyya, S.; Talukdar, B. (Department of Physics, Visva-Bharati University, Santiniketan-731 235 (India)); Mandal, P. (Department of Mathematics, Visva-Bharati University, Santiniketan-731 235 (India))
1995-01-01
A simple potential model proposed for the elastic scattering of positrons off rare-gas atoms is used to compute low-energy phase shifts and differential scattering cross sections [sigma]([theta]) for positrons incident on [sub 10]Ne, [sub 18]Ar, and [sub 36]Kr at energies 20, 3.4, and 6.67 eV, respectively. The calculated results for [sigma]([theta]) are in good agreement with currently available experimental values and are as reliable as the numbers obtained from much more elaborate calculations. It is pointed out that an important virtue of the present model is its simplicity.
Rayleigh scattering and nonlinear inversion of elastic waves
Energy Technology Data Exchange (ETDEWEB)
Gritto, Roland [Univ. of California, Berkeley, CA (United States)
1995-12-01
Rayleigh scattering of elastic waves by an inclusion is investigated and the limitations determined. In the near field of the inhomogeneity, the scattered waves are up to a factor of 300 stronger than in the far field, excluding the application of the far field Rayleigh approximation for this range. The investigation of the relative error as a function of parameter perturbation shows a range of applicability broader than previously assumed, with errors of 37% and 17% for perturbations of -100% and +100%, respectively. The validity range for the Rayleigh limit is controlled by large inequalities, and therefore, the exact limit is determined as a function of various parameter configurations, resulting in surprisingly high values of up to k_{p}R = 0.9. The nonlinear scattering problem can be solved by inverting for equivalent source terms (moments) of the scatterer, before the elastic parameters are determined. The nonlinear dependence between the moments and the elastic parameters reveals a strong asymmetry around the origin, which will produce different results for weak scattering approximations depending on the sign of the anomaly. Numerical modeling of cross hole situations shows that near field terms are important to yield correct estimates of the inhomogeneities in the vicinity of the receivers, while a few well positioned sources and receivers considerably increase the angular coverage, and thus the model resolution of the inversion parameters. The pattern of scattered energy by an inhomogeneity is complicated and varies depending on the object, the wavelength of the incident wave, and the elastic parameters involved. Therefore, it is necessary to investigate the direction of scattered amplitudes to determine the best survey geometry.
Quasi-Elastic Light Scattering in Ophthalmology
Ansari, Rafat R.
The eye is not just a "window to the soul"; it can also be a "window to the human body." The eye is built like a camera. Light which travels from the cornea to the retina traverses through tissues that are representative of nearly every tissue type and fluid type in the human body. Therefore, it is possible to diagnose ocular and systemic diseases through the eye. Quasi-elastic light scattering (QELS) also known as dynamic light scattering (DLS) is a laboratory technique routinely used in the characterization of macromolecular dispersions. QELS instrumentation has now become more compact, sensitive, flexible, and easy to use. These developments have made QELS/DLS an important tool in ophthalmic research where disease can be detected early and noninvasively before the clinical symptoms appear.
Differential Cross Sections for Proton-Proton Elastic Scattering
Norman, Ryan B.; Dick, Frank; Norbury, John W.; Blattnig, Steve R.
2009-01-01
Proton-proton elastic scattering is investigated within the framework of the one pion exchange model in an attempt to model nucleon-nucleon interactions spanning the large range of energies important to cosmic ray shielding. A quantum field theoretic calculation is used to compute both differential and total cross sections. A scalar theory is then presented and compared to the one pion exchange model. The theoretical cross sections are compared to proton-proton scattering data to determine the validity of the models.
Energy Technology Data Exchange (ETDEWEB)
Bazhukov, S.; Kibardin, A.; Pyatkova, T
2001-07-01
The processes of elastic scattering of the ions from thin-films systems have been modeled. The study is based on the proposed method of analysis of the composition of the beams of accelerated ions for investigation the beam formation in Van-de-Graaf generator and its influence on beam composition.
Bieber, R; Glockle, W; Golak, J; Harakeh, MN; Huber, D; Huisman, H; Kalantar-Nayestanaki, N; Kamada, H; Messchendorp, JG; Nogga, A; Sakai, H; Sakamoto, N; Seip, M; Volkerts, M; van der Werf, SY; Witala, H
2000-01-01
New vector analyzing-power data on (p) over right arrow+ d elastic scattering at E-p = 150 and 190 MeV have been measured. These an presented together with existing data and with recent (d) over right arrow + p vector and tensor analyzing power data at E-d = 270 MeV. The strong negative extremum of
Mapping from quasi-elastic scattering to fusion reactions
Directory of Open Access Journals (Sweden)
Hagino K.
2015-01-01
Full Text Available The fusion barrier distribution has provided a nice representation for the channel coupling effects on heavy-ion fusion reactions at energies around the Coulomb barrier. Here we discuss how one can extract the same representation using the so called sum-of-differences (SOD method with quasi-elastic scattering cross sections. In contrast to the conventional quasi-elastic barrier distribution, the SOD barrier distribution has an advantage in that it can be applied both to non-symmetric and symmetric systems. It is also the case that the correspondence to the fusion barrier distribution is much better than the quasi-elastic barrier distribution. We demonstrate its usefulness by studying 16O+144Sm, 58Ni+58Ni, and 12C+12C systems.
Elastic and Inelastic Scattering of Neutrons using a CLYC array
Brown, Tristan; Doucet, E.; Chowdhury, P.; Lister, C. J.; Wilson, G. L.; Devlin, M.; Mosby, S.
2015-10-01
CLYC scintillators, which have dual neutron and gamma response, have recently ushered in the possibility of fast neutron spectroscopy without time-of-flight (TOF). A 16-element array of 1'' x 1'' 6Li-depleted CLYC crystals, where pulse-shape-discrimination is achieved via digital pulse processing, has been commissioned at UMass Lowell. In an experiment at LANSCE, high energy neutrons were used to bombard 56Fe and 238U targets, in order to measure elastic and inelastic neutron scattering cross sections as a function of energy and angle with the array. The array is placed very close to the targets for enhanced geometrical solid angles for scattered neutrons compared to standard neutron-TOF measurements. A pulse-height spectrum of scattered neutrons in the detectors is compared to the energy of the incident neutrons, which is measured via the TOF of the pulsed neutrons from the source to the detectors. Recoil corrections are necessary to combine the energy spectra from all the detectors to obtain angle-integrated elastic and inelastic cross-sections. The detection techniques, analysis procedures and results will be presented. Supported by NNSA-SSAA program through DOE Grant DE-NA00013008.
2016-07-10
plane of the Hall thruster, ions do not necessarily have the energy equivalent to the potential difference between a cathode and an anode, as they...3 shows the center of mass deflection angle as a function of impact parameter for different center of mass energies . Note that Er = 150 eV roughly...Conference Paper with Briefing Charts 3. DATES COVERED (From - To) 02 June 2016 - 10 July 2016 4. TITLE AND SUBTITLE Fast Computation of High Energy
Generalizations of Karp's theorem to elastic scattering theory
Tuong, Ha-Duong
Karp's theorem states that if the far field pattern corresponding to the scattering of a time-harmonic acoustic plane wave by a sound-soft obstacle in R2 is invariant under the group of rotations, then the scatterer is a circle. The theorem is generalized to the elastic scattering problems and the axisymmetric scatterers in R3.
Elastic scattering of surface plasmon polaritons: Modeling and experiment
DEFF Research Database (Denmark)
Bozhevolnyi, Sergey I.; Coello, V.
1998-01-01
Elastic (in-plane) scattering of surface plasmon polaritons (SPP's) is modeled by considering isotropic pointlike scatterers whose responses to the incident SPP field are phenomenologically related to their effective polarizabilities. Numerical simulations of single, double, and multiple scattering...... are presented for randomly situated scatterers showing the interplay between different orders of scattering and localization phenomena. Correlation between the scattering regimes and spatial Fourier spectra of the corresponding SPP intensity distributions is considered. Various optical microcomponents (e...
Proton elastic scattering from stable and unstable nuclei - Extraction of nuclear densities
Sakaguchi, H.; Zenihiro, J.
2017-11-01
Progress in proton elastic scattering at intermediate energies to determine nuclear density distributions is reviewed. After challenges of about 15 years to explain proton elastic scattering and associated polarization phenomena at intermediate energies, we have reached to some conclusions regarding proton elastic scattering as a means of obtaining nuclear densities. During this same period, physics of unstable nuclei has become of interest, and the density distributions of protons and neutrons play more important roles in unstable nuclei, since the differences in proton and neutron numbers and densities are expected to be significant. As such, proton elastic scattering experiments at intermediate energies using the inverse kinematic method have started to determine density distributions of unstable nuclei. In the region of unstable nuclei, we are confronted with a new problem when attempting to find proton and neutron densities separately from elastic proton scattering data, since electron scattering data for unstable nuclei are not presently available. We introduce a new means of determining proton and neutron densities separately by double-energy proton elastic scattering at intermediate energies.
Energy Technology Data Exchange (ETDEWEB)
Gurchin, Yu.V., E-mail: gurchin@jinr.ru [LHEP-JINR, 141-980 Dubna, Moscow region (Russian Federation); Isupov, A.Yu. [LHEP-JINR, 141-980 Dubna, Moscow region (Russian Federation); Janek, M. [LHEP-JINR, 141-980 Dubna, Moscow region (Russian Federation); Physics Dept, University of vZilina, 010 26 Zilina (Slovakia); Karachuk, J.-T. [LHEP-JINR, 141-980 Dubna, Moscow region (Russian Federation); Advanced Research Institute for Electrical Engineering, Bucharest (Romania); Khrenov, A.N.; Krasnov, V.A.; Kurilkin, A.K.; Kurilkin, P.K.; Ladygin, V.P.; Ladygina, N.B.; Livanov, A.N.; Piyadin, S.M.; Rapatskiy, V.L.; Reznikov, S.G.; Terekhin, A.A.; Vasiliev, T.A. [LHEP-JINR, 141-980 Dubna, Moscow region (Russian Federation)
2011-10-15
The preliminary results on the cross-section of dp-elastic scattering reaction obtained at 880 and 500 MeV at internal target of Nuclotron are presented. The measurements have been performed using CH{sub 2} and C targets and kinematic coincidence of signals from scintillation counters. The cross-section data at 880 MeV are compared with the different theoretical predictions.
Reexamination of the Energy Levels of 15F by 14O + 1H ElasticResonance Scattering with BEARS
Energy Technology Data Exchange (ETDEWEB)
Guo, F.Q.; Powell, J.; Lee, D.W.; Leitner, D.; McMahan, M.A.; Moltz, D.M.; O' Neil, J.P.; Perajarvi, K.; Phair, L.; Ramsey, C.A.; Xu,X.J.; Cerny, Joseph
2005-05-30
The energy levels of 15F have been measured by the p(14O,p)14O reaction. The 120 MeV 14O radioactive ion beam was produced by the BEARS coupled cyclotron system at an intensity averaging 1x104 particles/second on target. Energy calibration was obtained using resonances from the p(14N,p)14N reaction. The two lowest resonances in 15F were fitted with an R-matrix calculation. The fit to the ground state had Jp = 1/2+ at 1.23+-0.05 MeV (width 0.5-0.84 MeV), and the first excited state was Jp=5/2+ at 2.81+-0.02 MeV (width 0.30+-0.06 MeV), both relative to the mass-energy of the proton and 14O. The 15F ground state energy supports the disappearance of the Z=8 proton magic number for odd Z, Tz=-3/2 nuclei.
Khoa, D T; Bohlen, H G; Nuoffer, F
2000-01-01
The experimental data on elastic sup 1 sup 6 O+ sup 1 sup 6 O scattering at incident energies ranging from 124 to 1120 MeV have been analyzed within the standard optical model (OM), using either the phenomenological (Woods-Saxon squared) potential or that calculated within the double-folding model for the real part of the optical potential. Structure of the elastic cross sections at smallest scattering angles was found to be of a pure diffractive nature, which enabled a consistent check of the absolute normalization of the elastic data under study. The OM analysis shows unambiguously the evolution of the refractive scattering pattern in the sup 1 sup 6 O+ sup 1 sup 6 O system over this energy range. The large angle region of the data is dominated by the refractive far-side scattering. The oscillating Airy structure can be consistently described by a set of optical potentials with the real part given by the folding model and a weak absorptive imaginary potential.
Kiss, G.G.(Institute for Nuclear Research (MTA ATOMKI), Debrecen, H-4001, Hungary); Mohr, P; Fülöp, Zs.; Gyürky, Gy.(Institute for Nuclear Research (MTA ATOMKI), Debrecen, H-4001, Hungary); Elekes, Z.; Farkas, J.; Somorjai, E.; Yalcin, C.; Galaviz, D.; Güray, R T; Özkan, N; Görres, J.
2011-01-01
The elastic scattering cross sections for the reactions $^{110,116}$Cd($\\alpha,\\alpha$)$^{110,116}$Cd at energies above and below the Coulomb barrier are presented to provide a sensitive test for the alpha-nucleus optical potential parameter sets. Additional constraints for the optical potential are taken from the analysis of elastic scattering excitation functions at backward angles which are available in literature. Moreover, the variation of the elastic alpha scattering cross sections alon...
Elastic scattering and fusion cross-sections in Li + Al reaction
Indian Academy of Sciences (India)
Abstract. With an aim to understand the effects of breakup and transfer channels on elastic scat- tering and fusion cross-sections in the 7Li + 27Al reaction, simultaneous measurement of elastic scattering angular distributions and fusion cross-sections have been carried out at various energies. (Elab = 8.0–16.0 MeV) around ...
Quasi-elastic Charm Production In Neutrino-nucleon Scattering
Bischofberger, M
2005-01-01
A study of quasi elastic charm production in charged current neutrino-nucleon scattering is presented. A sample of about 1.3 million interactions recorded with the NOMAD detector in the CERN SPS wide band neutrino beam has been searched for quasi elastically produced charmed baryons ( L+c,Sc and S*c ). The search has been performed in two exclusive decay channels of the L+c, both including a L . Also, the semi-inclusive decay channels L+c,Sc,S *c→L+X have been studied. Kinematic selection criteria have been chosen in order to obtain samples enriched with quasi elastic charm events. Signal efficiencies and background expectations have been estimated by Monte Carlo simulations. The observed number of events in each searched channel has been found to agree with the background expectation from charged and neutral current reactions and an upper limit for the cross section has been derived. For the quasi elastic charm production cross section averaged over the neutrino energy spectrum (&lan...
Hassan, M. A. M.; Nour El-Din, M. S. M.; Ellithi, A.; Hosny, H.; Salama, T. N. E.
2017-10-01
In the framework of Glauber optical limit approximation where Coulomb effect is taken into account, the elastic scattering differential cross section for halo nuclei with {}^{12}{C} at 800 MeV/N has been calculated. Its sensitivity to the halo densities and the root mean square of the core and halo is the main goal of the current study. The projectile nuclei are taken to be one-neutron and two-neutron halo. The calculations are carried out for Gaussian-Gaussian, Gaussian-Oscillator and Gaussian-2 s phenomenological densities for each considered projectile in the mass number range 6-29. Also included a comparison between the obtained results of phenomenological densities and the results within the microscopic densities LSSM of {}6{He} and {}^{11}{Li} and microscopic densities GCM of {}^{11}{Be} where the density of the target nucleus {}^{12}{C} obtained from electron-{}^{12}{C} scattering is used. The zero range approximation is considered in the calculations. We found that the sensitivity of elastic scattering differential cross section to the halo density is clear if the nucleus appears as two clear different clusters, core and halo.
A New Optimal Bound on Logarithmic Slope of Elastic Hadron-Hadron Scattering
Ion, D B
2005-01-01
In this paper we prove a new optimal bound on the logarithmic slope of the elastic slope when: elastic cross section and differential cross sections in forward and backward directions are known from experimental data. The results on the experimental tests of this new optimal bound are presented in Sect. 3 for the principal meson-nucleon elastic scatterings: pion-nucleon, kaon-nucleon at all available energies. Then we have shown that the saturation of this optimal bound is observed with high accuracy practically at all available energies in meson-nucleon scattering.
Exploring central opacity and asymptotic scenarios in elastic hadron scattering
Fagundes, D. A.; Menon, M. J.; Silva, P. V. R. G.
2016-02-01
In the absence of a global description of the experimental data on elastic and soft diffractive scattering from the first principles of QCD, model-independent analyses may provide useful phenomenological insights for the development of the theory in the soft sector. With that in mind, we present an empirical study on the energy dependence of the ratio X between the elastic and total cross sections; a quantity related to the evolution of the hadronic central opacity. The dataset comprises all the experimental information available on proton-proton and antiproton-proton scattering in the c.m. energy interval 5 GeV-8 TeV. Generalizing previous works, we discuss four model-independent analytical parameterizations for X, consisting of sigmoid functions composed with elementary functions of the energy and three distinct asymptotic scenarios: either the standard black disk limit or scenarios above or below that limit. Our two main conclusions are the following: (1) although consistent with the experimental data, the black disk does not represent an unique solution; (2) the data reductions favor a semi-transparent scenario, with asymptotic average value for the ratio X bar = 0.30 ± 0.12. In this case, within the uncertainty, the asymptotic regime may already be reached around 1000 TeV. We present a comparative study of the two scenarios, including predictions for the inelastic channel (diffraction dissociation) and the ratio associated with the total cross-section and the elastic slope. Details on the selection of our empirical ansatz for X and physical aspects related to a change of curvature in this quantity at 80-100 GeV, indicating the beginning of a saturation effect, are also presented and discussed.
Energy Technology Data Exchange (ETDEWEB)
Camacho, A. G.; Aguilera, E. F.; Quiroz, E. M. [Departamento de Aceleradores, ININ, La Marquesa, 52750 Estado de Mexico (Mexico); Gomes, P. R. S.; Lubian, J. [Instituto de Fisica, Universidade Federal Fluminenese, Av. Litoranea s/n, Gragoata, Niteroi, 24210-340 Rio de Janeiro (Brazil)
2008-12-15
The energy dependence of the optical potential is used to study the threshold anomaly for reactions with the weakly bound projectile {sup 9}Be on {sup 144}Sm and {sup 64}Zn for energies around the Coulomb barrier. The energy dependent potential parameters are obtained from a simultaneous X{sup 2}-analysis of elastic scattering and fusion data. There are signatures that in fact, the so-called breakup threshold anomaly shows up for these systems. This finding is in agreement with other calculations involving weakly bound projectiles. (Author)
Uniqueness in inverse elastic scattering with finitely many incident waves
Energy Technology Data Exchange (ETDEWEB)
Elschner, Johannes [Weierstrass-Institut fuer Angewandte Analysis und Stochastik (WIAS) im Forschungsverbund Berlin e.V. (Germany); Yamamoto, Masahiro [Tokyo Univ. (Japan). Dept. of Mathematical Sciences
2009-07-01
We consider the third and fourth exterior boundary value problems of linear isotropic elasticity and present uniqueness results for the corresponding inverse scattering problems with polyhedral-type obstacles and a finite number of incident plane elastic waves. Our approach is based on a reflection principle for the Navier equation. (orig.)
Effects of elastic and inelastic scattering in giving electrons tortuous paths in matter.
Turner, J E; Hamm, R N
1995-09-01
Heavy charged particles travel in essentially straight lines in matter, while electrons travel in tortuous paths. Frequent multiple elastic Coulomb scattering by atomic nuclei is often cited as the reason for this electron behavior. Heavy charged particles also undergo multiple Coulomb scattering. However, because they are massive, significant deflections occur only in rare, close encounters with nuclei. In contrast to heavy particles, the inelastic interaction of an electron with an atomic electron represents a collision with a particle of equal mass. In principle, therefore, repeated inelastic scattering of an electron can also produce large-angle deflections and thus contribute to the tortuous nature of an electron's track. To investigate the relative importance of elastic and inelastic scattering on determining the appearance of electron tracks, detailed Monte Carlo transport computations have been carried out for monoenergetic pencil beams of electrons normally incident on a water slab with initial energies from 1 keV to 1 MeV. The calculations have been performed with deflections due to (1) inelastic scattering only, (2) elastic scattering only, and (3) both types of scattering. Results are presented to show the spreading of the pencil beams with depth in the slab, the transmission through slabs of different thicknesses, and back-scattering from the slab. The results show that elastic nuclear scattering is indeed the principal physical process that causes electron paths to be tortuous; however, the smaller effect of inelastic electronic scattering is far from negligible.
Comparative study of alpha + nucleus elastic scattering using different models
Al-Ghamdi, A. H.; Ibraheem, Awad A.; El-Azab Farid, M.
2015-01-01
The alpha (α) elastic scattering from different targets potential over the energy range 10-240 MeV has been analyzed in the framework of the single-folding (SF) optical model. Four targets are considered, namely, 24Mg, 28Si, 32S and 40Ca. The SF calculations for the real central part of the nuclear optical potential are performed by folding an effective α-α interaction with the α-cluster distribution density in the target nucleus. The imaginary part of the optical potential is expressed in the phenomenological Woods-Saxon (WS) form. The calculated angular distributions of the elastic scattering differential cross-section using the derived semimicroscopic potentials successfully reproduce 36 sets of data all over the measured angular ranges. The obtained results confirm the validity of the α-cluster structure of the considered nuclei. For the sake of comparison, the same sets of data are reanalyzed using microscopic double-folded optical potentials based upon the density-dependent Jeukenne-Lejeune-Mahaux (JLM) effective nucleon-nucleon interaction.
Energy Technology Data Exchange (ETDEWEB)
Toth, G.; Zavodszky, P.; Bhalla, C.P.; Richard, P.; Grabbe, S.; Aliabadi, H. [Kansas State Univ., Manhattan, KS (United States). Dept. of Physics
2001-07-01
Absolute double differential cross sections for the electron production at zero degree laboratory observation angle were measured for high velocity hydrogenic carbon, nitrogen, oxygen and fluorine ions on molecular hydrogen. The energies of these ions were chosen so the elastic scattering resonance 2p{sup 2} {sup 1}D for each case can be clearly observed near the peak of the binary encounter electron distribution. Close coupling R-matrix calculations of elastic differential cross sections of electron impact of these ions were related to the measured ion-atom cross sections by using the elastic scattering model (ESM). Excellent agreement was found between theory and experimental data. (orig.)
Amos, N.; Block, M.M.; Bobbink, G.J.; Botje, M.A.J.; Favart, D.; Leroy, C.; Linde, F.; Lipnik, P.; Matheys, J-P.; Miller, D.
1985-01-01
Antiproton-proton and proton-proton small-angle elastic scattering was measured for centre-of-mass energies at the CERN Intersectung Storage Rings. In addition, proton-proton elastic scattering was measured at . Using the optical theorem, total cross sections are obtained with an accuracy of about
Measurement of T20 in Elastic Electron-Deuteron Scattering
Bouwhuis, M.; Alarcon, R.; Botto, T.; Brand, J. F. J. van den; Bulten, H. J.; Dolfini, S.; Ent, R.; Ferro-Luzzi, M.; Higinbotham, D.W.; de Jager, C.W.; Lang, J.; de Lange, J.; Papadakis, N.; Passchier, I.; Poolman, H. R.; Six, E.; Steijger, J.J.M.; Vodinas, N.; Vries, H. de; Zhou, Z. -L.
1998-01-01
We report on a measurement of the tensor-analyzing power T20 in elastic electron-deuteron scattering in the range of four-momentum transfer from 1.8 to 3.2 fm-1. Electrons of 704 MeV were scattered from a polarized deuterium internal target. The tensor polarization of the deuterium nuclei was
Energy Technology Data Exchange (ETDEWEB)
Androic, D; Armstrong, D S; Bailey, S L; Beck, D H; Beise, E J; Benesch, J; Benmokhtar, F; Bimbot, L; Birchall, J; Bosted, P; Breuer, K; Capuano, C L; Chao, Y -C; Coppens, A; Davis, C A; Ellis, C; Flores, G; Franklin, G; Furget, C; Gaskell, D; Gericke, M.T.W.; Grames, J; Guillard, G; Hansknecht, J; Horn, T; Jones, M K; King, P M; Korsch, W; Kox, S; Lee, L; Liu, J; Lung, A; Mammei, J; Martin, J W; McKeown, R D; Micherdzinska, A; Mihovilovic, M; Mkrtchyan, H; Muether, M; Page, S A; Papavassiliou, V; Pate, S F; Phillips, S K; Pillot, P; Pitt, M L; Poelker, M; Quinn, B; Ramsay, W D; Real, J -S; Roche, J; Roos, P; Schaub, J; Seva, T; Simicevic, N; Smith, G R; Spayde, D T; Stutzman, M; Suleiman, R; Tadevosyan, V; van Oers, W.T.H.; Versteegen, M; Voutier, E; Vulcan, W; Wells, S P; Williamson, S E; Wood, S A; Pasquini, B
2011-07-01
We have measured the beam-normal single-spin asymmetries in elastic scattering of transversely polarized electrons from the proton, and performed the first measurement in quasi-elastic scattering on the deuteron, at backward angles (lab scattering angle of 108 degrees) for Q2 = 0.22 GeV^2/c^2 and 0.63 GeV^2/c^2 at beam energies of 362 MeV and 687 MeV, respectively. The asymmetry arises due to the imaginary part of the interference of the two-photon exchange amplitude with that of single photon exchange. Results for the proton are consistent with a model calculation which includes inelastic intermediate hadronic (piN) states. An estimate of the beam-normal single-spin asymmetry for the scattering from the neutron is made using a quasi-static deuterium approximation, and is also in agreement with theory.
Elastic scattering of positronium: Application of the confined variational method
Zhang, Junyi
2012-08-01
We demonstrate for the first time that the phase shift in elastic positronium-atom scattering can be precisely determined by the confined variational method, in spite of the fact that the Hamiltonian includes an unphysical confining potential acting on the center of mass of the positron and one of the atomic electrons. As an example, we study the S-wave elastic scattering for the positronium-hydrogen scattering system, where the existing 4% discrepancy between the Kohn variational calculation and the R-matrix calculation is resolved. © Copyright EPLA, 2012.
Slope analysis for elastic proton-proton and proton-antiproton scattering
Okorokov, V. A.
2008-01-01
The diffraction slope parameter is investigated for elastic proton-proton and proton-antiproton scattering based on the all available experimental data at intermediate square of momentum transfer in the main. Energy dependence of the elastic diffraction slope is approximated by various analytic functions in a model-independent fashion. The expanded standard logarithmic approximations allow to describe experimental slopes in all available energy range at qualitative level reasonably. Various f...
Xu, Jing; Li, Bin; Zhou, Chuanping; Xiao, Jing; Ni, Jing
2017-07-01
An experimental investigation of wetting behavior of liquid droplet on texture vibrating substrate and the theoretical calculations of elastic wave scattering with two holes which based on the elastodynamics, employing complex functions are investigated to study the relationship between texture vibrating plate dynamic wettability and elastic wave scattering. Experimental results show the dynamic behavior of droplet was unstable. In 0 to π/2 cycle, droplet appeared the waveform with front steep and rear gentle along the flow direction. In π/2 to π cycle, droplet appeared slightly periodic oscillation and accompanied by a certain ripple. Based on the dynamic wetting phenomenon in a single cycle, the influence of elastic wave scattering on wetting property are analyzed. Analysis has shown that the stress concentration is caused by complex elastic wave scattering. The more concentrated the stress, the more concentrated the elastic wave energy. Compared with the single hole, the variations of dynamic stress concentration factors for two holes are complex due to the influence of interaction between two holes. Droplet emerge movement is response to the local vibration. The vibration spread in elastic plate at a time of strain, this elastic force cause droplet displacement and vibration, and accompanied with energy transfer.
Scattering of Airy elastic sheets by a cylindrical cavity in a solid.
Mitri, F G
2017-11-01
The prediction of the elastic scattering by voids (and cracks) in materials is an important process in structural health monitoring, phononic crystals, metamaterials and non-destructive evaluation/imaging to name a few examples. Earlier analytical theories and numerical computations considered the elastic scattering by voids in plane waves of infinite extent. However, current research suggesting the use of (limited-diffracting, accelerating and self-healing) Airy acoustical-sheet beams for non-destructive evaluation or imaging applications in elastic solids requires the development of an improved analytical formalism to predict the scattering efficiency used as a priori information in quantitative material characterization. Based on the definition of the time-averaged scattered power flow density, an analytical expression for the scattering efficiency of a cylindrical empty cavity (i.e., void) encased in an elastic medium is derived for compressional and normally-polarized shear-wave Airy beams. The multipole expansion method using cylindrical wave functions is utilized. Numerical computations for the scattering energy efficiency factors for compressional and shear waves illustrate the analysis with particular emphasis on the Airy beam parameters and the non-dimensional frequency, for various elastic materials surrounding the cavity. The ratio of the compressional to the shear wave speed stimulates the generation of elastic resonances, which are manifested as a series of peaks in the scattering efficiency plots. The present analysis provides an improved method for the computations of the scattering energy efficiency factors using compressional and shear-wave Airy beams in elastic materials as opposed to plane waves of infinite extent. Copyright © 2017 Elsevier B.V. All rights reserved.
Unified quantum theory of elastic and inelastic atomic scattering from a physisorbed monolayer solid
DEFF Research Database (Denmark)
Bruch, L. W.; Hansen, Flemming Yssing; Dammann, Bernd
2017-01-01
the wave functions for elastic and inelastic scattered atoms. An attenuation of diffraction scattering by inelastic processes thus is inherent in the theory. The atomic motion and monolayer vibrations in the harmonic approximation are treated quantum mechanically and unitarity is preserved. The evaluation......A unified quantum theory of the elastic and inelastic scattering of low energy He atoms by a physisorbed monolayer solid in the one-phonon approximation is given. It uses a time-dependent wave packet with phonon creation and annihilation components and has a self-consistent feedback between...
Strong coupling effects in near-barrier heavy-ion elastic scattering
Energy Technology Data Exchange (ETDEWEB)
Keeley, N. [National Centre for Nuclear Research, Otwock (Poland); Kemper, K.W. [The Florida State University, Department of Physics, Tallahassee, Florida (United States); University of Warsaw, Heavy Ion Laboratory, Warsaw (Poland); Rusek, K. [University of Warsaw, Heavy Ion Laboratory, Warsaw (Poland)
2014-09-15
Accurate elastic scattering angular distribution data measured at bombarding energies just above the Coulomb barrier have shapes that can markedly differ from or be the same as the expected classical Fresnel scattering pattern depending on the structure of the projectile, the target or both. Examples are given such as {sup 18}O + {sup 184}W and {sup 16}O + {sup 148,} {sup 152}Sm, where the expected rise above Rutherford scattering due to Coulomb-nuclear interference is damped by coupling to the target excited states, and the extreme case of {sup 11}Li scattering, where coupling to the {sup 9}Li + n + n continuum leads to an elastic scattering shape that cannot be reproduced by any standard optical model parameter set. An early indication that the projectile structure can modify the elastic scattering angular distribution was the large vector analyzing powers observed in polarised {sup 6}Li scattering. The recent availability of high-quality {sup 6}He, {sup 11}Li and {sup 11}Be data provides further examples of the influence that coupling effects can have on elastic scattering. Conditions for strong projectile-target coupling effects are presented with special emphasis on the importance of the beam-target charge combination being large enough to bring about the strong coupling effects. Several measurements are proposed that can lead to further understanding of strong coupling effects by both inelastic excitation and nucleon transfer on near-barrier elastic scattering. A final note on the anomalous nature of {sup 8}B elastic scattering is presented as it possesses a more or less normal Fresnel scattering shape whereas one would a priori not expect this due to the very low breakup threshold of {sup 8}B. The special nature of {sup 11}Li is presented as it is predicted that no matter how far above the Coulomb barrier the elastic scattering is measured, its shape will not appear as Fresnel like whereas the elastic scattering of all other loosely bound nuclei studied to
Muon Elastic Scattering with MUSE at PSI
Directory of Open Access Journals (Sweden)
Kohl M.
2014-03-01
Full Text Available The proton radius puzzle is the disagreement between the much more precise radius determined from muonic hydrogen spectroscopy and the numerous atomic hydrogen and electron scattering determinations. The puzzle has several possible resolutions, including physics beyond the Standard Model, missing conventional physics, and errors or underestimated uncertainties in the extraction of the radius from the data. New experiments are needed to confirm and / or resolve the puzzle. The MUon Scattering Experiment (MUSE recently approved at PSI has been designed to help resolve the puzzle by measuring the radius in a way not yet done. Similar to electron scattering, the radius will be extracted from the observed change of the charge form factor with momentum transfer. The experiment uses the πM1 beamline to provide a mixed secondary muon and electron (and pion beam of either positive or negative charge. The comparison of muon and electron scattering measured simultaneously determines the consistency of the form factors in the two cases with high precision. Comparison of yields from both charge signs will at the same time disentangle the effect of two-photon exchange. The proton charge radius can be extracted from each set of scattering data. The physics case and status of MUSE will be discussed.
Elastic scattering, polarization and absorption of relativistic antiprotons on nuclei
Larionov, A. B.; Lenske, H.
2017-01-01
We perform Glauber model calculations of the antiproton-nucleus elastic and quasielastic scattering and absorption in the beam momentum range ∼ 0.5 ÷ 10 GeV / c. A good agreement of our calculations with available LEAR data and with earlier Glauber model studies of the p bar A elastic scattering allows us to make predictions at the beam momenta of ∼10 GeV/c, i.e. at the regime of the PANDA experiment at FAIR. The comparison with the proton-nucleus elastic scattering cross sections shows that the diffractive minima are much deeper in the p bar A case due to smaller absolute value of the ratio of the real-to-imaginary part of the elementary elastic amplitude. Significant polarization signal for p bar A elastic scattering at 10 GeV/c is expected. We have also revealed a strong dependence of the p bar A absorption cross section on the slope parameter of the transverse momentum dependence of the elementary p bar N amplitude. The p bar A optical potential is discussed.
Spin–spin correlations and entanglement in elastic electron scattering from hydrogen atoms
Bartschat, Klaus
2017-11-01
In two recent papers, Blum and Lohmann (2016 Phys. Rev. Lett. 116 033201) and Lohmann et al (2016 Phys. Rev. A 94 032331), the possibility of continuously varying the degree of entanglement between an elastically scattered electron and the valence electron of quasi-one electron targets was discussed. Here we present results for elastic electron scattering from atomic hydrogen in the energy regime of 1‑10 eV and the full range of scattering angles 0^\\circ -180^\\circ . We confirm previous calculations at very low energies, which predicted that the hydrogen target is not a promising candidate for Bell correlations through electron collisions. This finding remains unchanged in the near-resonance regime of incident electron energies just below 10 eV. In addition to the spin-correlation parameter P, we present the angle-integrated total cross section, as well as the angle-differential cross section at a few representative collision energies.
Semenov, Alexander; Babikov, Dmitri
2014-01-28
The mixed quantum/classical theory (MQCT) for rotationally inelastic scattering developed recently [A. Semenov and D. Babikov, J. Chem. Phys. 139, 174108 (2013)] is benchmarked against the full quantum calculations for two molecular systems: He + H2 and Na + N2. This allows testing new method in the cases of light and reasonably heavy reduced masses, for small and large rotational quanta, in a broad range of collision energies and rotational excitations. The resultant collision cross sections vary through ten-orders of magnitude range of values. Both inelastic and elastic channels are considered, as well as differential (over scattering angle) cross sections. In many cases results of the mixed quantum/classical method are hard to distinguish from the full quantum results. In less favorable cases (light masses, larger quanta, and small collision energies) some deviations are observed but, even in the worst cases, they are within 25% or so. The method is computationally cheap and particularly accurate at higher energies, heavier masses, and larger densities of states. At these conditions MQCT represents a useful alternative to the standard full-quantum scattering theory.
Quasi-elastic laser light scattering study of polyacrylamide hydrogel ...
Indian Academy of Sciences (India)
Polyacrylamide (PAAm) hydrogels immersed in water and aqueous NaCl solutions were investigated for their structure and dynamics using static and quasi-elastic laser light scattering (QELS) techniques. Ensemble-averaged electric field correlation function (, ) obtained from the non-ergodic analysis of ...
Resonance Elastic Scattering and Interference Effects Treatments in Subgroup Method
Directory of Open Access Journals (Sweden)
Yunzhao Li
2016-04-01
Full Text Available Based on the resonance integral (RI tables produced by the NJOY program, the conventional subgroup method usually ignores both the resonance elastic scattering and the resonance interference effects. In this paper, on one hand, to correct the resonance elastic scattering effect, RI tables are regenerated by using the Monte Carlo code, OpenMC, which employs the Doppler broadening rejection correction method for the resonance elastic scattering. On the other hand, a fast resonance interference factor method is proposed to efficiently handle the resonance interference effect. Encouraging conclusions have been indicated by the numerical results. (1 For a hot full power pressurized water reactor fuel pin-cell, an error of about +200 percent mille could be introduced by neglecting the resonance elastic scattering effect. By contrast, the approach employed in this paper can eliminate the error. (2 The fast resonance interference factor method possesses higher precision and higher efficiency than the conventional Bondarenko iteration method. Correspondingly, if the fast resonance interference factor method proposed in this paper is employed, the kinf can be improved by ∼100 percent mille with a speedup of about 4.56.
The second Born approximation of electron–argon elastic scattering ...
Indian Academy of Sciences (India)
We study the elastic scattering of atomic argon by electron in the presence of a bichromatic laser ﬁeld in the second Born approximation. The target atom is approximated by a simple screening potential and the continuum states of the impinging and emitting electrons are described as Volkov states. We evaluate the S-matrix ...
Direct and inverse scattering by an elastic inclusion
Pelekanos, George
1997-11-01
The problem of two-dimensional scattering of elastic waves by an elastic inclusion can be formulated in terms of a domain integral equation, in which the grad-div operator acts on a vector potential. The vector potential is the spatial convolution of a Green's function with the product of the density and the displacement over the domain of interest. The first part of the thesis treats the numerical solution of the direct problem. Following similar work done in electromagnetics we employ a Galerkin approximation using a weak form of the integral equation and rooftop functions, as both expansion and test functions. The determination of the approximate elastic field is thus reduced to an algebraic problem. We present some numerical results for coaxially coated cylinders with constant Lame coefficients and variable densities. The numerical results are compared with existing analytical solutions. The second part of the thesis is concerned with the inverse problem of determining the density of an elastic inclusion from a knowledge of how the inclusion scatters known incident elastic waves. A modified gradient method which is based on the integral representation of the field is used for the solution of the inverse problem. The algorithm employed is an extension of the Kleinman- Van den Berg method to elasticity, and involves an iterative determination of both the unknown density and the shape of the inclusion. The synthetic data used in the inversion algorithm is obtained using the numerical solution of the direct problem developed in the first part of the dissertation.
Numerical modelling of multiple scattering between two elastical particles
DEFF Research Database (Denmark)
Bjørnø, Irina; Jensen, Leif Bjørnø
1998-01-01
is higher than 20 g/l of sand particles. This paper reports an attempt to illuminate and to solve the proximity threshold question, by an in-depth numerical study of the interaction of ultrasonic signals with two canonically shaped elastic particles. Introductory experimental results seem to create evidence...... for the applicability of this new numerical model...... in suspension have been studied extensively since Foldy's formulation of his theory for isotropic scattering by randomly distributed scatterers. However, a number of important problems related to multiple scattering are still far from finding their solutions. A particular, but still unsolved, problem...
The neutron-deuteron elastic scattering angular distribution at 95 MeV
Energy Technology Data Exchange (ETDEWEB)
Mermod, Philippe
2004-04-01
The neutron-deuteron elastic scattering differential cross section has been measured at 95 MeV incident neutron energy, with the Medley setup at TSL in Uppsala. The neutron-proton differential cross section has also been measured for normalization purposes. The data are compared with theoretical calculations to investigate the role of three-nucleon force effects.
Elastic proton scattering on tritium below the n-3He threshold
Directory of Open Access Journals (Sweden)
Lazauskas R.
2010-04-01
Full Text Available Microscopic calculations using Faddeev-Yakubovski equations in conﬁguration space are performed for low energy elastic proton scattering on 3H nucleus. Realistic nuclear Hamiltonians are used. Coulomb repulsion between the protons as well as isospin breaking eﬀects are rigorously treated.
Quasi-elastic neutron scattering study of the mobility of methane in microporous silica
Benes, Nieck Edwin; Jobic, Herve; Verweij, H.
2001-01-01
The dynamics of translation and rotation of methane in microporous bulk silica have been studied with quasi-elastic neutron scattering. At T=200 K the self-diffusion coefficient of translation is DS=1.1×10−8 m2 s−1 with an estimated activation energy of 4 kJ mol−1. Any variation of DS with occupancy
Excitation function of elastic $pp$ scattering from a unitarily extended Bialas-Bzdak model
Nemes, F.; Csanád, M.
2015-01-01
The Bialas-Bzdak model of elastic proton-proton scattering assumes a purely imaginary forward scattering amplitude, which consequently vanishes at the diffractive minima. We extended the model to arbitrarily large real parts in a way that constraints from unitarity are satisfied. The resulting model is able to describe elastic $pp$ scattering not only at the lower ISR energies but also at $\\sqrt{s}=$7~TeV in a statistically acceptable manner, both in the diffractive cone and in the region of the first diffractive minimum. The total cross-section as well as the differential cross-section of elastic proton-proton scattering is predicted for the future LHC energies of $\\sqrt{s}=$13, 14, 15~TeV and also to 28~TeV. A non-trivial, significantly non-exponential feature of the differential cross-section of elastic proton-proton scattering is analyzed and the excitation function of the non-exponential behavior is predicted. The excitation function of the shadow profiles is discussed and related to saturation at small ...
Crossing the Dripline to 11N Using Elastic Resonance Scattering
Markenroth, K G; Baxter, S; García-Borge, M J; Donzaud, C; Fayans, S; Fynbo, H O U; Goldberg, V Z; Grévy, S; Guillemaud-Müller, D; Jonson, B; Kallman, K M; Leenhardt, S; Lewitowicz, M; Lönnroth, T; Manngard, P; Martel, I; Müller, A C; Mukha, I; Nilsson, T; Nyman, G H; Orr, N A; Riisager, K; Rogachev, G V; Saint-Laurent, M G; Serikov, I N; Shulgina, N B; Sorlin, O; Steiner, M; Tengblad, O; Thoennessen, M; Tryggestad, E J; Trzaska, W H; Wenander, F; Winfield, J S; Wolski, R
2000-01-01
The level structure of the unbound nucleus 11N has been studied by 10C+p elastic resonance scattering in inverse geometry with the LISE3 spectrometer at GANIL, using a 10C beam with an energy of 9.0 MeV/u. An additional measurement was done at the A1200 spectrometer at MSU. The excitation function above the 10C+p threshold has been determined up to 5 MeV. A potential-model analysis revealed three resonance states at energies 1.27 (+0.18-0.05) MeV (Gamma=1.44 +-0.2 MeV), 2.01(+0.15-0.05) MeV, (Gamma=0.84 +-$0.2 MeV) and 3.75(+-0.05) MeV, (Gamma=0.60 +-0.05 MeV) with the spin-parity assignments I(pi) =1/2+, 1/2- and 5/2+, respectively. Hence, 11N is shown to have a ground state parity inversion completely analogous to its mirror partner, 11Be. A narrow resonance in the excitation function at 4.33 (+-0.05) MeV was also observed and assigned spin-parity 3/2-.
Decoherence due to elastic rayleigh scattering
CSIR Research Space (South Africa)
Uys, H
2010-11-01
Full Text Available for gates in quan- tum computing [1], the generation of spin squeezed states through laser-mediated interactions [2–6], and the trapping and manipulation of neutral atoms in optical lattices [7,8]. These experiments frequently involve superpositions... by [13] Ldu ~�SðtÞ ¼ ��du2 ð�^ ��^þ ~�SðtÞ � 2�^þ ~�SðtÞ�^� þ ~�SðtÞ�^��^þÞ; Lud ~�SðtÞ ¼ ��ud2 ð�^ þ�^� ~�SðtÞ � 2�^� ~�SðtÞ�^þ þ ~�SðtÞ�^þ�^�Þ: �ij is the rate for an ion initially in state jii to scatter a photon and end up in state jji...
Mechanism of elastic and inelastic proton scattering on a {sup 15}C nucleus in diffraction theory
Energy Technology Data Exchange (ETDEWEB)
Ibraeva, E. T., E-mail: ibr@inp.kz [National Nuclear Center of the Republic of Kazakhstan, Institute of Nuclear Physics (Kazakhstan); Zhusupov, M. A. [Al-Farabi Kazakh National University (Kazakhstan); Imambekov, O. [National Nuclear Center of the Republic of Kazakhstan, Institute of Nuclear Physics (Kazakhstan)
2012-11-15
The amplitudes for elastic and inelastic proton scattering on the neutron-rich nucleus {sup 15}C (to its J{sup {pi}} = 5/2{sup +} level in the latter case) in inverse kinematics were calculated within Glauber diffraction theory. First- and second-order terms were taken into account in the multiple-scattering operator. The {sup 15}C wave function in the multiparticle shell model was used. This made it possible to calculate not only respective differential cross sections but also the contribution of proton scattering on nucleons occurring in different shells. The differential cross sections for elastic and inelastic scattering were calculated at the energies of 0.2, 0.6, and 1 GeV per nucleon.
Structure of light neutron-rich nuclei and mechanism of elastic proton scattering
Energy Technology Data Exchange (ETDEWEB)
Ibraeva, E. T., E-mail: ibr@inp.kz [National Nuclear Center of the Republic of Kazakhstan, Institute of Nuclear Physics (Kazakhstan); Zhusupov, M. A. [Al-Farabi Kazakh National University (Kazakhstan); Imambekov, O. [National Nuclear Center of the Republic of Kazakhstan, Institute of Nuclear Physics (Kazakhstan)
2011-11-15
Differential cross sections for elastic p{sup 6}He, p{sup 8}Li, and p{sup 9}Li scattering at two energies of 70 and 700 MeV per nucleon were calculated within the Glauber theory of multiple diffractive scattering. Threeparticle wave functions ({alpha}-n-n for {sup 6}He, {alpha}-t-n for {sup 8}Li, and {sup 7}Li-n-n for {sup 9}Li) were used for realistic potentials of intercluster interactions. The sensitivity of elastic scattering to proton-nucleus interaction and to the structure of nuclei was explored. In particular, the dependence of the differential cross section on the contribution of higher order collisions, on scattering on the core and peripheral nucleons, and on the contribution of small wave-function components and their asymptotic behavior was determined. A comparison with available experimental data and with the results of calculations within different formalisms was performed.
Resonance estimates for single spin asymmetries in elastic electron-nucleon scattering
Energy Technology Data Exchange (ETDEWEB)
Barbara Pasquini; Marc Vanderhaeghen
2004-07-01
We discuss the target and beam normal spin asymmetries in elastic electron-nucleon scattering which depend on the imaginary part of two-photon exchange processes between electron and nucleon. We express this imaginary part as a phase space integral over the doubly virtual Compton scattering tensor on the nucleon. We use unitarity to model the doubly virtual Compton scattering tensor in the resonance region in terms of {gamma}* N {yields} {pi} N electroabsorption amplitudes. Taking those amplitudes from a phenomenological analysis of pion electroproduction observables, we present results for beam and target normal single spin asymmetries for elastic electron-nucleon scattering for beam energies below 1 GeV and in the 1-3 GeV region, where several experiments are performed or are in progress.
Energy Technology Data Exchange (ETDEWEB)
Liao, C.; Hagmann, S.; Bhalla, C.P.; Grabbe, S.R.; Cocke, C.L.; Richard, P. [J. R. Macdonald Laboratory, Kansas State University, Manhattan, Kansas 66506 (United States); Liao, C. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States)
1999-04-01
We present a method of deriving energy and angle-dependent electron-ion elastic scattering cross sections from doubly differential cross sections for electron emission in ion-atom collisions. By analyzing the laboratory frame binary encounter electron production cross sections in energetic ion-atom collisions, we derive projectile frame differential cross sections for electrons elastically scattered from highly charged projectile ions in the range between 60{degree} and 180{degree}. The elastic scattering cross sections are observed to deviate strongly from the Rutherford cross sections for electron scattering from bare nuclei. They exhibit strong Ramsauer-Townsend electron diffraction in the angular distribution of elastically scattered electrons, providing evidence for the strong role of screening played in the collision. Experimental data are compared with partial-wave calculations using the Hartree-Fock model. {copyright} {ital 1999} {ital The American Physical Society}
Benchmark measurements of non-Rutherford proton elastic scattering cross section for boron
Energy Technology Data Exchange (ETDEWEB)
Chiari, M. [INFN-Sezione di Firenze, Sesto Fiorentino, Florence I-50019 (Italy); Bianconi, M. [CNR-IMM-UOS di Bologna, Bologna I-40129 (Italy); Bogdanović Radović, I. [Ruder Boskovic Institute, Zagreb 10002 (Croatia); Mayer, M. [Max-Planck-Institut für Plasmaphysik, D-85748 Garching (Germany)
2015-01-15
In the literature several elastic scattering cross-sections data sets are available for protons on {sup 10}B and {sup 11}B at energies and scattering angles suitable for elastic backscattering spectrometry (EBS) analysis. However, agreement between these different data sets is generally poor, with systematic differences up to 20%, well beyond the stated absolute uncertainties. To resolve the conflict between the different data sets in the absence of the evaluated cross-section data, a benchmark experiment was performed. Proton backscattering spectra were obtained with a thick uniform B{sub 4}C target at beam energies in the range of 2.0–4.0 MeV and at different scattering angles, followed by a standard direct simulation with the SIMNRA code using the available experimental cross-section data. As a result, recommendation on the most appropriate data set to be used in proton EBS analysis of boron is given.
Gómez Camacho, A.
2015-01-01
Calculations of elastic scattering angular distributions for reactions of the weakly bound projectile 6Li with targets 144Sm and 208Pb at energies above the barrier, are performed with the Continuum Discretized Coupled-Channel method (CDCC). Ground, resonant and nonresonant continuum states of 6Li are included up to some maximum energy epsilonmax for which convergence is achieved. In the three-body system, global interactions are used for the α-target and d - target sub-systems. The effect of continuum resonant states of 6Li, i.e., l = 2, jπ = 3+, 2+ and 1+ on elastic scattering angular distributions is investigated by extracting these states from the continuum space. It is found that the calculated elastic scattering angular distributions are in good agreement with the measurements for most of the cases studied where consideration of couplings to continuum states is essential. It is also found that the resonance character of the continuum states is in some cases important to obtain agreement with the data.
Measurement of $T_{20}$ in Elastic Electron-Deuteron Scattering
Bouwhuis, M; Botto, T; Van den Brand, J F J; Bulten, H J; Dolfini, S M; Ent, R; Ferro-Luzzi, M; Higinbotham, D W; De Jager, C W; Lang, J; De Lange, D J; Papadakis, N H; Passchier, I; Poolman, H R; Six, E; Steijger, J J M; Vodinas, N P; De Vries, H; Zhou, Z L
1999-01-01
We report on a measurement of the tensor-analyzing power T20 in elastic electron-deuteron scattering in the range of four-momentum transfer from 1.8 to 3.2 fm-1. Electrons of 704 MeV were scattered from a polarized deuterium internal target. The tensor polarization of the deuterium nuclei was determined with an ion-extraction system, allowing an absolute measurement of T20. The data are described well by a non-relativistic calculation that includes the effects of meson-exchange currents.
pi --p Elastic Scattering at 1.44 Bev
Steinberger, J; Schwartz, M; Samios, Nicholas P; Leitner, Jack
1957-01-01
An investigation of pi -+p elastic scattering, made in a liquid propane bubble chamber, is reported. Identification of events is made on the basis of kinematics. The problem of contamination by pion scattering from protons bound in carbon is considered in some detail; it is shown that the latter requires a correction of only 4±2.5% of the total number of events. The angular distribution is presented. It shows a large diffraction peak at small angles and an approximately isotropic plateau over the backward hemisphere. The forward peak is fitted to a black-sphere diffraction pattern with a radius of (1.08±0.06) x 10-13 cm. The total elastic cross section is found to be sigma e=10.1±0.80 mb.
Inversion problem for ion-atom differential elastic scattering.
Rich, W. G.; Bobbio, S. M.; Champion, R. L.; Doverspike, L. D.
1971-01-01
The paper describes a practical application of Remler's (1971) method by which one constructs a set of phase shifts from high resolution measurements of the differential elastic scattering of protons by rare-gas atoms. These JWKB phase shifts are then formally inverted to determine the corresponding intermolecular potentials. The validity of the method is demonstrated by comparing an intermolecular potential obtained by direct inversion of experimental data with a fairly accurate calculation by Wolniewicz (1965).
Energy Technology Data Exchange (ETDEWEB)
Doster, W. [Physik-Department, Technische Universität München, D-85748 Garching (Germany); Nakagawa, H. [Jülich Centre for Neutron Science, Forschungszentrum Jülich GmbH, Outstation at MLZ, Lichtenbergstraße 1, 85747 Garching (Germany); Japan Atomic Energy Agency, Quantum Beam Science Directorate, Tokai, Ibaraki 319-1195 (Japan); Appavou, M. S. [Jülich Centre for Neutron Science, Forschungszentrum Jülich GmbH, Outstation at MLZ, Lichtenbergstraße 1, 85747 Garching (Germany)
2013-07-28
Numerous neutron scattering studies of bio-molecular dynamics employ a qualitative analysis of elastic scattering data and atomic mean square displacements. We provide a new quantitative approach showing that the intensity at zero energy exchange can be a rich source of information of bio-structural fluctuations on a pico- to nano-second time scale. Elastic intensity scans performed either as a function of the temperature (back-scattering) and/or by varying the instrumental resolution (time of flight spectroscopy) yield the activation parameters of molecular motions and the approximate structural correlation function in the time domain. The two methods are unified by a scaling function, which depends on the ratio of correlation time and instrumental resolution time. The elastic scattering concept is illustrated with a dynamic characterization of alanine-dipeptide, protein hydration water, and water-coupled protein motions of lysozyme, per-deuterated c-phycocyanin (CPC) and hydrated myoglobin. The complete elastic scattering function versus temperature, momentum exchange, and instrumental resolution is analyzed instead of focusing on a single cross-over temperature of mean square displacements at the apparent onset temperature of an-harmonic motions. Our method predicts the protein dynamical transition (PDT) at T{sub d} from the collective (α) structural relaxation rates of the solvation shell as input. By contrast, the secondary (β) relaxation enhances the amplitude of fast local motions in the vicinity of the glass temperature T{sub g}. The PDT is specified by step function in the elastic intensity leading from elastic to viscoelastic dynamic behavior at a transition temperature T{sub d}.
Acoustic and elastic multiple scattering and radiation from cylindrical structures
Amirkulova, Feruza Abdukadirovna
Multiple scattering (MS) and radiation of waves by a system of scatterers is of great theoretical and practical importance and is required in a wide variety of physical contexts such as the implementation of "invisibility" cloaks, the effective parameter characterization, and the fabrication of dynamically tunable structures, etc. The dissertation develops fast, rapidly convergent iterative techniques to expedite the solution of MS problems. The formulation of MS problems reduces to a system of linear algebraic equations using Graf's theorem and separation of variables. The iterative techniques are developed using Neumann expansion and Block Toeplitz structure of the linear system; they are very general, and suitable for parallel computations and a large number of MS problems, i.e. acoustic, elastic, electromagnetic, etc., and used for the first time to solve MS problems. The theory is implemented in Matlab and FORTRAN, and the theoretical predictions are compared to computations obtained by COMSOL. To formulate the MS problem, the transition matrix is obtained by analyzing an acoustic and an elastic single scattering of incident waves by elastic isotropic and anisotropic solids. The mathematical model of wave scattering from multilayered cylindrical and spherical structures is developed by means of an exact solution of dynamic 3D elasticity theory. The recursive impedance matrix algorithm is derived for radially heterogeneous anisotropic solids. An explicit method for finding the impedance in piecewise uniform, transverse-isotropic material is proposed; the solution is compared to elasticity theory solutions involving Buchwald potentials. Furthermore, active exterior cloaking devices are modeled for acoustic and elastic media using multipole sources. A cloaking device can render an object invisible to some incident waves as seen by some external observer. The active cloak is generated by a discrete set of multipole sources that destructively interfere with an
Spin entanglement in elastic electron scattering from quasi-one electron atoms
Fonseca Dos Santos, Samantha; Bartschat, Klaus
2017-04-01
We have extended our work on e-Li collisions to investigate low-energy elastic electron collisions with atomic hydrogen and other alkali targets (Na,K,Rb). These systems have been suggested for the possibility of continuously varying the degree of entanglement between the elastically scattered projectile and the valence electron. In order to estimate how well such a scheme may work in practice, we carried out overview calculations for energies between 0 and 10 eV and the full range of scattering angles 0° -180° . In addition to the relative exchange asymmetry parameter that characterizes the entanglement, we present the differential cross section in order to estimate whether the count rates in the most interesting energy-angle regimes are sufficient to make such experiments feasible in practice. Work supported by the NSF under PHY-1403245.
Modeling proton and alpha elastic scattering in liquid water in Geant4-DNA
Energy Technology Data Exchange (ETDEWEB)
Tran, H.N., E-mail: tranngochoang@tdt.edu.vn [Division of Nuclear Physics, Ton Duc Thang University, Tan Phong Ward, District 7, Ho Chi Minh City (Viet Nam); Faculty of Applied Sciences, Ton Duc Thang University, Tan Phong Ward, District 7, Ho Chi Minh City (Viet Nam); El Bitar, Z. [Institut Pluridisciplinaire Hubert Curien/IN2P3/CNRS, Strasbourg (France); Champion, C. [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Karamitros, M. [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, INCIA, UMR 5287, F-33400 Talence (France); Bernal, M.A. [Instituto de FísicaGleb Wataghin, Universida de Estadual de Campinas, SP (Brazil); Francis, Z. [Université Saint Joseph, Faculty of Science, Department of Physics, Beirut (Lebanon); The Open University, Faculty of Science, Department of Physical Sciences, Walton Hall, MK7 6AA Milton Keynes (United Kingdom); Ivantchenko, V. [Ecoanalytica, 119899 Moscow (Russian Federation); Lee, S.B.; Shin, J.I. [Proton Therapy Center, National Cancer Center, 323 Ilsan-ro, Ilsandong-gu, Goyang-si, Gyeonggi-do 410-769 (Korea, Republic of); Incerti, S. [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France)
2015-01-15
Elastic scattering of protons and alpha (α) particles by water molecules cannot be neglected at low incident energies. However, this physical process is currently not available in the “Geant4-DNA” extension of the Geant4 Monte Carlo simulation toolkit. In this work, we report on theoretical differential and integral cross sections of the elastic scattering process for 100 eV–1 MeV incident protons and for 100 eV–10 MeV incident α particles in liquid water. The calculations are performed within the classical framework described by Everhart et al., Ziegler et al. and by the ICRU 49 Report. Then, we propose an implementation of the corresponding classes into the Geant4-DNA toolkit for modeling the elastic scattering of protons and α particles. Stopping powers as well as ranges are also reported. Then, it clearly appears that the account of the elastic scattering process in the slowing-down of the charged particle improves the agreement with the existing data in particular with the ICRU recommendations.
Quantum scattering at low energies
DEFF Research Database (Denmark)
Derezinski, Jan; Skibsted, Erik
2009-01-01
For a class of negative slowly decaying potentials, including V(x):=−γ|x|−μ with 0quantum mechanical scattering theory in the low-energy regime. Using appropriate modifiers of the Isozaki–Kitada type we show that scattering theory is well behaved on the whole continuous spectrum...
Quantum scattering at low energies
DEFF Research Database (Denmark)
Derezinski, Jan; Skibsted, Erik
For a class of negative slowly decaying potentials, including with , we study the quantum mechanical scattering theory in the low-energy regime. Using modifiers of the Isozaki--Kitada type we show that scattering theory is well behaved on the {\\it whole} continuous spectrum of the Hamiltonian...
Microscopic description of elastic and direct inelastic nucleon scattering off spherical nuclei
Energy Technology Data Exchange (ETDEWEB)
Dupuis, M. [CEA, DAM, DIF, Arpajon (France)
2017-05-15
The purpose of this study is to improve the modeling of nucleon direct inelastic scattering to the continuum using a microscopic and parameter-free approach. For the first time, direct elastic scattering, inelastic scattering to discrete excitations and to the continuum are described within a microscopic approach without adjustable parameters. Proton scattering off {sup 90}Zr and {sup 208}Pb are the reactions used as test case examples of the calculations. The model uses the Melbourne g-matrix and the Random Phase Approximation description of nuclear states, implemented with the Gogny D1S interaction. The relevant optical and transition potentials in a finite nucleus are calculated within a local density approximation. As we use the nuclear matter approach we limit our study to incident energies above 40 MeV. We first checked that this model provides an accurate account of measured cross sections for elastic scattering and inelastic scattering to discrete states. It is then applied to the direct inelastic scattering to the continuum considering all one-phonon excitations predicted within the RPA approach. This accounts for a part of the direct pre-equilibrium emission, often labeled as the one-step direct process in quantum-based approaches. Our approach provides a very accurate description of angular distributions where the one-step process dominates. The impact of collective excitations is shown to be non negligible for energy transfer to the target up to 20 MeV, decreasing as the incident energy increases. For incident energies above 80 MeV, our modeling provides a good account of direct proton emission for an energy transfer to the target up to 30 MeV. However, the proton emission we predict underestimates the measured cross sections for incident energies below 80 MeV. We compare our prediction to those of the phenomenological exciton model to help interpret this result. Directions that may improve our modeling are discussed. (orig.)
Effects of target polarization in electron elastic scattering off endohedral A @C60
Dolmatov, V. K.; Amusia, M. Ya.; Chernysheva, L. V.
2017-01-01
We have developed an efficient approximation to describe the low-energy electron elastic scattering off an endohedral fullerene A @CN . It accounts for polarization of A @CN by incoming electrons without reference to complicated details of the electronic structure of CN itself. The developed approach has permitted us to unravel spectacular A @CN polarization effects in low-energy e-+A @CN elastic scattering, particularly the effects due to interelectron interaction between the electrons of both CN and A . We show that contribution of a single atom A remains unscreened by the multiatomic CN despite the fact that the projectile's wavelength is bigger than the size of the target. Inclusion of A and CN polarizability interference leads to violation of the previously predicted phase additivity rule. The partial scattering cross sections acquire prominent Ramsauer-type minima which, however, disappear in the total cross section. The study reveals notable trends in e-+A @CN elastic scattering versus the polarizability of an encapsulated atom. We also predict the existence of certain negative ions A @CN- . We chose Ne, Xe, and Ba as atoms A , and C60 as the endohedral CN, as the case study. The work focuses on a reasonable compromise between the qualitative and quantitative aspects of the problem in general rather than on carrying out detailed calculations for one particular system.
Strange Nucleon Form Factors from ep and vp Elastic Scattering
Energy Technology Data Exchange (ETDEWEB)
Pate, S.F. [Physics Department, New Mexico State University, Las Cruces NM 88003 (United States)]. e-mail: pate@nmsu.edu
2007-12-15
The recent parity-violating ep forward-scattering elastic asymmetry data from Jefferson Lab (HAPPEx and G0), when combined with the vp elastic cross section data from Brookhaven (E734), permit an extraction of the strangeness contribution to the vector and axial nucleon form factors for momentum transfers in the range 0.45 < Q{sup 2} < 1.0 GeV{sup 2}. These results, combined with the recent determination of the strange vector form factors at Q{sup 2} = 0.1 GeV{sup 2} (SAMPLE, HAPPEx, PVA4, G0) have been interpreted in terms of uudss{sup -} configurations very different from the kaon-loop configurations usually associated with strangeness in the nucleon. New experiments are being proposed to improve the state of our knowledge of the vp elastic cross section -- these new experiments will push the range of Q{sup 2} to much lower values, and greatly increase the precision of the vp elastic data. One outcome of this can be a measurement of the strangeness contribution to the nucleon spin, {delta}s. Nuclear targets (e.g. C or Ar) are to be used in these neutrino experiments, and so a deep understanding of the nuclear physics, particularly in regard to final state effects, is needed before the potential of these precision experiments can be fully realized. (Author)
Elastic and inelastic scattering of neutrons on 238U nucleus
Directory of Open Access Journals (Sweden)
Capote R.
2014-04-01
Full Text Available Advanced modelling of neutron induced reactions on the 238U nucleus is aimed at improving our knowledge of neutron scattering. Capture and fission channels are well constrained by available experimental data and neutron standard evaluation. A focus of this contribution is on elastic and inelastic scattering cross sections. The employed nuclear reaction model includes – a new rotational-vibrational dispersive optical model potential coupling the low-lying collective bands of vibrational character observed in even-even actinides; – the Engelbrecht-Weidenmüller transformation allowing for inclusion of compound-direct interference effects; – and a multi-humped fission barrier with absorption in the secondary well described within the optical model for fission. Impact of the advanced modelling on elastic and inelastic scattering cross sections including angular distributions and emission spectra is assessed both by comparison with selected microscopic experimental data and integral criticality benchmarks including measured reaction rates (e.g. JEMIMA, FLAPTOP and BIG TEN. Benchmark calculations provided feedback to improve the reaction modelling. Improvement of existing libraries will be discussed.
Spin asymmetries for elastic proton scattering and the spin-dependent couplings of the Pomeron
Trueman, T. L.
2008-03-01
This paper serves as a report on the large amount of analysis done in conjunction with the polarized proton program at the Relavitistic Heavy Ion Collider at Brookhaven National Laboratory. This comprises elastic scattering data of protons on protons in colliding beam or fixed target mode and proton beams on carbon targets. In addition to providing a model for the energy dependence of the analyzing power of elastic scattering needed for proton polarimetry, it also provides some significant information about the spin dependence of dominant Regge poles. Most notably, the data indicate that the Pomeron has a significant spin-flip coupling. This allows the exploration of the double-spin flip asymmetry ANN for which some data over a wide energy range are now available, along with a concrete realization of a proposed Odderon search.
Elastic scattering and reaction mechanisms of the halo nucleus $^{11}$Be around the Coulomb barrier
Di Pietro, A; Fisichella, M; Borge, M J G; Randisi, G; Milin, M; Figuera, P; Gomez-Camacho, J; Raabe, R; Amorini, F; Fraile, L M; Rizzo, F; Zadro, M; Torresi, D; Wenander, F; Pellegriti, M G; Papa, M; Jeppesen, H; Santonocito, D; Scuderi, V; Acosta, L; Perez-Bernal, F; Tengblad, O; Lattuada, M; Musumarra, A; Scalia, G; Maira Vidal, A; Voulot, D
2010-01-01
Collisions induced by $^{9}$Be, $^{10}$Be, $^{11}$Be on a $^{64}$Zn target at the same c. m. energy were studied. For the first time, strong effects of the $^{11}$Be halo structure on elastic-scattering and reaction mechanisms at energies near the Coulomb barrier are evidenced experimentally. The elastic-scattering cross section of the $^{11}$Be halo nucleus shows unusual behavior in the Coulomb-nuclear interference peak angular region. The extracted total-reaction cross section for the $^{11}$Be collision is more than double the ones measured in the collisions induced by $^{9}$Be, $^{10}$Be. It is shown that such a strong enhancement of the total-reaction cross section with $^{11}$Be is due to transfer and breakup processes.
Investigation of 16O+16O elastic scattering using the α-cluster folding model
Hassanain, M. A.; Ibraheem, Awad A.; Al Sebiey, Shikha M. M.; Mokhtar, S. R.; Zaki, M. A.; Mahmoud, Zakaria M. M.; Behairy, K. O.; Farid, M. El-Azab
2013-06-01
Angular distributions of 16O+16O elastic scattering at energies that range from 124 to 1120 MeV have been analyzed in the framework of the double folding (DF) optical model. Based upon the α-cluster structure of the 16O nucleus, two different versions of the real DF optical potential have been generated by using three effective α-α, α-nucleon (N) and nucleon-nucleon (NN) interactions. A microscopic optical potential built upon the M3Y effective NN interaction and the matter density distribution of the 16O nucleus has also been extracted. The obtained real potentials, in conjunction with phenomenological squared Woods-Saxon imaginary parts, have successfully reproduced seven sets of elastic-scattering data. No renormalization of the real folded α-cluster potentials is required to fit the data. The energy dependence of the extracted real and imaginary volume integrals and total reaction cross section has also been investigated.
{sup 12}C+p resonant elastic scattering in the Maya active target
Energy Technology Data Exchange (ETDEWEB)
Sambi, S.; Raabe, R.; Flavigny, F.; Khodery, M. [KU Leuven, Instituut voor Kern- en Stralingsfysica, Physics Department, Leuven (Belgium); Borge, M.J.G. [CERN, PH Department, Geneva (Switzerland); Caamano, M.; Fernandez-Dominguez, B. [Universidade de Santiago de Compostela, Department of Particle Physics, Santiago de Compostela (Spain); Damoy, S.; Grinyer, G.F.; Pancin, J.; Perez-Loureiro, D.; Roger, T. [CEA/DSM - CNRS/IN2P3, Grand Accelerateur National d' Ion Lourds (GANIL), Caen (France); Fynbo, H. [Aarhus University, Department of Physics and Astronomy, Aarhus (Denmark); Gibelin, J. [Universite de Caen, CNRS/IN2P3, LPC Caen, ENSICAEN, Caen Cedex (France); Heinz, A.; Jonson, B.; Nilsson, T.; Thies, R. [Chalmers University of Technology, Department of Physics, Goteborg (Sweden); Orlandi, R. [KU Leuven, Instituut voor Kern- en Stralingsfysica, Physics Department, Leuven (Belgium); Instituto de Estructura de la Materia CSIC, Madrid (Spain); JAEA, ASRC, Tokai-mura (Japan); Randisi, G. [KU Leuven, Instituut voor Kern- en Stralingsfysica, Physics Department, Leuven (Belgium); CEA/DSM - CNRS/IN2P3, Grand Accelerateur National d' Ion Lourds (GANIL), Caen (France); Ribeiro, G.; Tengblad, O. [Instituto de Estructura de la Materia CSIC, Madrid (Spain); Suzuki, D. [Universite Paris-Sud, Institut de Physique Nucleaire, CNRS/IN2P3, Orsay (France); Datta, U. [Saha Institute of Nuclear Physics, Kolkata (India)
2015-03-01
In a proof-of-principle measurement, the Maya active target detector was employed for a {sup 12}C(p, p) resonant elastic scattering experiment in inverse kinematics. The excitation energy region from 0 to 3MeV above the proton breakup threshold in {sup 13}N was investigated in a single measurement. By using the capability of the detector to localize the reaction vertex and record the tracks of the recoiling protons, data covering a large solid angle could be utilized, at the same time keeping an energy resolution comparable with that of direct-kinematics measurements. The excitation spectrum in {sup 13}N was fitted using the R-matrix formalism. The level parameters extracted are in good agreement with previous studies. The active target proved its potential for the study of resonant elastic scattering in inverse kinematics with radioactive beams, when detection efficiency is of primary importance. (orig.)
Elastic scattering of sup 58 Ni+ sup 64 Ni near the Coulomb barrier
Energy Technology Data Exchange (ETDEWEB)
Stefanini, A.M.; Xu Jincheng; Corradi, L.; Montagnoli, G.; Moreno, H.; Nagashima, Y.; Mueller, L.; Narayanasamy, M.; Napoli, D.R.; Spolaore, P. (Istituto Nazionale di Fisica Nucleare, Padua (Italy). Lab. di Legnaro); Beghini, S.; Scarlassara, F.; Segato, G.F.; Soramel, F. (Padua Univ. (Italy). Dipt. di Fisica Istituto Nazionale di Fisica Nucleare, Padua (Italy)); Signorini, C. (Salerno Univ. (Italy). Dipt. di Fisica Istituto Nazionale di Fisica Nucleare, Padua (Italy)); Esbensen, H.; Landowne, S. (Argonne National Lab., IL (USA). Physics Div.); Pollarolo, G. (Turin Univ. (Italy). Dipt. di Fisica Istituto Nazionale di Fisica Nucleare, Turin (Italy))
1990-04-26
Elastic scattering angular distributions have been measured for {sup 58}Ni+{sup 64}Ni at three energies around the Coulomb barrier employing a new kinematic coincidence technique. The data are compared with the results of coupled-channels calculations including inelastic excitations as well as one- and two-neutron transfer reactions. The agreement is good and the calculations also agree well with the available transfer and fusion reaction data. (orig.).
Elastic scattering and fusion studies in the reactions $^{10,11}$Be + $^{64}$Zn
2002-01-01
We propose to measure elastic scattering and fusion excitation functions for the reactions $^{10,11}$Be + $^{64}$Zn at 3.1 MeV/u . The aim of the experiment is to investigate possible effects of the halo structure of the $^{11}$Be nucleus on the reaction mechanisms at energy around the Coulomb barrier. For this purpose a comparison with the reaction induced by the $^{10}$Be nucleus is required.
We intend to measure the structure of the unbound nucleus $^{21}$Al via resonance elastic and inelastic scattering with an active target. There are many goals: \\\\ a) to locate the 1/2$^{+}$ level in $^{21}$Al that brings information on the Thomas-Ehrman shift, \\\\ b) to measure the energy spectrum of $^{21}$Al which is a N=8 isotone with the resonance elastic scattering reaction, \\\\ c) to investigate via inelastic scattering the strength of core excitations in the existence of narrow unbound resonances beyond the proton drip-line.
A recoil detector for the measurement of antiproton-proton elastic scattering at angles close to 90
Energy Technology Data Exchange (ETDEWEB)
Hu, Q. [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China); Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); University of Chinese Academy of Sciences, Beijing (China); Bechstedt, U.; Gillitzer, A.; Grzonka, D.; Lehrach, A.; Prasuhn, D.; Sefzick, T.; Stockmanns, T.; Xu, H. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Khoukaz, A.; Taeschner, A. [Universitaet Muenster, Institut fuer Kernphysik, Muenster (Germany); Klehr, F.; Wuestner, P. [Elektronik und Analytik, Forschungszentrum Juelich, Zentralinstitut fuer Engineering, Juelich (Germany); Ritman, J. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Ruhr-Universitaet Bochum, Bochum (Germany)
2014-10-15
The design and construction of a recoil detector for the measurement of recoil protons of antiproton-proton elastic scattering at scattering angles close to 90 {sup circle} are described. The performance of the recoil detector has been tested in the laboratory with radioactive sources and at COSY with proton beams by measuring proton-proton elastic scattering. The results of laboratory tests and commissioning with beam are presented. Excellent energy resolution and proper working performance of the recoil detector validate the conceptual design of the KOALA experiment at HESR to provide the cross section data needed to achieve a precise luminosity determination at the PANDA experiment. (orig.)
A recoil detector for the measurement of antiproton-proton elastic scattering at angles close to 90°
Hu, Q.; Bechstedt, U.; Gillitzer, A.; Grzonka, D.; Khoukaz, A.; Klehr, F.; Lehrach, A.; Prasuhn, D.; Ritman, J.; Sefzick, T.; Stockmanns, T.; Täschner, A.; Wuestner, P.; Xu, H.
2014-10-01
The design and construction of a recoil detector for the measurement of recoil protons of antiproton-proton elastic scattering at scattering angles close to are described. The performance of the recoil detector has been tested in the laboratory with radioactive sources and at COSY with proton beams by measuring proton-proton elastic scattering. The results of laboratory tests and commissioning with beam are presented. Excellent energy resolution and proper working performance of the recoil detector validate the conceptual design of the KOALA experiment at HESR to provide the cross section data needed to achieve a precise luminosity determination at the PANDA experiment.
Note on the elastic-scattering of few-MeV neutrons from elemental calcium
Energy Technology Data Exchange (ETDEWEB)
Smith, A.B.; Guenther, P.T.
1982-03-01
Neutron differential-elastic-scattering cross sections of elemental calcium are measured from < 1.5 to 4.0 MeV at intervals of approx. = 50 to 100 keV. Scattering angles are distributed between 20 and 160/sup 0/. Incident-neutron energy resolutions are approximately 50 to 100 keV. The experimental results are compared with values given in ENDF/B-V and are examined in the context of shielding applications. An optical potential is deduced from the measured values and its possible implications are discussed.
Parity Violation in Forward Angle Elastic Electron-Proton Scattering
Energy Technology Data Exchange (ETDEWEB)
Miller, IV, Grady Wilson [Princeton Univ., NJ (United States)
2001-01-01
We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from the proton at Jefferson Laboratory. The kinematic point (θ_{lab} = 12.3 deg. and (Q^{2}) = 0.48 (GeV/c)^{2}) is chosen to provide sensitivity to the strange electric form factor G^{s}_{E}. A 3.36 GeV beam of longitudinally polarized electrons was scattered from protons in a liquid hydrogen target. The scattered flux was detected by a pair of spectrometers which focussed the elastically-scattered electrons onto total-absorption detectors. The detector signals were integrated and digitized by a custom data acquisition system. A feedback system reduced systematic errors by controlling helicity-correlated beam intensity differences at the sub-ppm (part per million) level. The experimental result, A = 14.5 +/- 2.0 (stat) ± 1.1 (syst) ppm, is consistent with the electroweak Standard Model with no additional contributions from strange quarks. In particular, the measurement implies G^{S}_{E} + 0.39 G^{s}_{M} = 0.023 ± 0.040 ± 0.026 (ζG^{n}_{E}), where the last uncertainty is due to the estimated uncertainty in the neutron electric form factor G^{n}_{E} . This result represents the first experimental constraint of the strange electric form factor.
Polarization observables in low-energy antiproton-proton scattering
Zhou, Daren; Timmermans, Rob G. E.
2013-01-01
We investigate the polarization parameters in low-energy antiproton-proton elastic ((p) over barp -> (p) over barp) and charge-exchange ((p) over barp -> (n) over barn) scattering. The predictions for unmeasured observables are based on our new energy-dependent partial-wave analysis of all
Luminosity monitoring at OLYMPUS with forward-angle elastic scattering
Ates, Ozgur; Olympus Collaboration
2013-10-01
The OLYMPUS experiment at DESY has taken data during two periods in 2012 to measure the ratio of positron-proton and electron-proton elastic scattering cross sections. The goal of OLYMPUS is to quantify the effect of two-photon exchange, which is widely considered to be responsible for the discrepancy between measurements of the proton electric to magnetic form factor ratio with the Rosenbluth separation and polarization transfer methods. In order to control the systematic uncertainties to the sub-percent level, the luminosities have been monitored redundantly and with high precision by measuring the rates for symmetric Moller and Bhabha scattering, and by measuring the ep-elastic count rates at forward angles and low momentum transfer with tracking telescopes based on GEM (Gas Electron Multiplier) and MWPC (Multi Wire Proportional Chamber) technology. Based on the data analysis of GEM and MWPC luminosity monitors, detector performances and preliminary results on the positron/electron luminosity ratio will be presented. Supported by NSF grants 0855473, 0959521, 1207672, and by DOE Early Career Award DE-SC0003884.
Population and energy elasticity of tornado casualties
Fricker, Tyler; Elsner, James B.; Jagger, Thomas H.
2017-04-01
Tornadoes are capable of catastrophic destruction and mass casualties, but there are yet no estimates of how sensitive the number of casualties are to changes in the number of people in harm's way or to changes in tornado energy. Here the relationship between tornado casualties (deaths and injuries), population, and energy dissipation is quantified using the economic concept of "elasticity." Records of casualties from individual tornadoes over the period 2007-2015 are fit to a regression model. The coefficient on the population term (population elasticity) indicates that a doubling in population increases the casualty rate by 21% [(17, 24)%, 95% credible interval]. The coefficient on the energy term (energy elasticity) indicates that a doubling in energy dissipation leads to a 33% [(30, 35)%, 95% credible interval] increase in the casualty rate. The difference in elasticity values show that on average, changes in energy dissipation have been relatively more important in explaining tornado casualties than changes in population. Assuming no changes in warning effectiveness or mitigation efforts, these elasticity estimates can be used to project changes in casualties given the known population trends and possible trends in tornado activity.
Compton sources for the observation of elastic photon-photon scattering events
Directory of Open Access Journals (Sweden)
D. Micieli
2016-09-01
Full Text Available We present the design of a photon-photon collider based on conventional Compton gamma sources for the observation of elastic γγ scattering. Two symmetric electron beams, generated by photocathodes and accelerated in linacs, produce two primary gamma rays through Compton backscattering with two high energy lasers. The elastic photon-photon scattering is analyzed by start-to-end simulations from the photocathodes to the detector. A new Monte Carlo code has been developed ad hoc for the counting of the QED events. Realistic numbers of the secondary gamma yield, obtained by using the parameters of existing or approved Compton devices, a discussion of the feasibility of the experiment and of the nature of the background are presented.
Elastic {pi}{pi} scattering up to 2 GeV and the meson resonance spectrum
Energy Technology Data Exchange (ETDEWEB)
Kloet, W.M. [Rutgers - the State Univ., Piscataway, NJ (United States). Dept. of Physics and Astronomy; Loiseau, B. [Division de Physique Theorique, Institut de Physique Nucleaire, 91406, Orsay CEDEX (France)]|[LPTPE, Universite P. and M. Curie, 4 Place Jussieu, 75252, Paris CEDEX 05 (France)
1998-03-02
Elastic {pi}{pi} scattering from threshold to 2.0 GeV is predicted by a coupled channel model of {pi}{pi}, anti KK, and {rho}{rho}({omega}{omega}). As input the S-matrix of the model is required to exhibit poles for the complex energies, corresponding to the J{sup PC}(I{sup G})=0{sup ++}(0{sup +}), 1{sup --}(1{sup +}), 2{sup ++}(0{sup +}), 3{sup --}(1{sup +}) resonances of the Particle Data Group. One important aspect is that the scattering amplitude in this three-channel model, has an analytic structure in the complex energy plane with eight possible sheets. As output the model describes the S,P,D,F-wave {pi}{pi} scattering amplitudes as parametrized by phase shifts and inelasticities. (orig.). 5 refs.
Geometry Survey of the Time-of-Flight Neutron-Elastic Scattering (Antonella) Experiment
Energy Technology Data Exchange (ETDEWEB)
Oshinowo, Babatunde O. [Fermilab; Izraelevitch, Federico [Buenos Aires U.
2016-10-17
The Antonella experiment is a measurement of the ionization efficiency of nuclear recoils in silicon at low energies [1]. It is a neutron elastic scattering experiment motivated by the search for dark matter particles. In this experiment, a proton beam hits a lithium target and neutrons are produced. The neutron shower passes through a collimator that produces a neutron beam. The beam illuminates a silicon detector. With a certain probability, a neutron interacts with a silicon nucleus of the detector producing elastic scattering. After the interaction, a fraction of the neutron energy is transferred to the silicon nucleus which acquires kinetic energy and recoils. This kinetic energy is then dissipated in the detector producing ionization and thermal energy. The ionization produced is measured with the silicon detector electronics. On the other hand, the neutron is scattered out of the beam. A neutron-detector array (made of scintillator bars) registers the neutron arrival time and the scattering angle to reconstruct the kinematics of the neutron-nucleus interaction with the time-of-flight technique [2]. In the reconstruction equations, the energy of the nuclear recoil is a function of the scattering angle with respect to the beam direction, the time-of-flight of the neutron and the geometric distances between components of the setup (neutron-production target, silicon detector, scintillator bars). This paper summarizes the survey of the different components of the experiment that made possible the off-line analysis of the collected data. Measurements were made with the API Radian Laser Tracker and I-360 Probe Wireless. The survey was completed at the University of Notre Dame, Indiana, USA in February 2015.
Nucleon momentum distributions and elastic electron scattering form ...
Indian Academy of Sciences (India)
Electrons interact with nuclei basically through the electromagnetic force. If the energy of the electrons is high enough, they become a relatively clean probe to explore precisely the internal structure of the nuclei [7]. There are many reasons why inclusive electron scattering provides a powerful tool for studying the structure of ...
Neutron Angular Scatter Effects in 3DHZETRN: Quasi-Elastic
Wilson, John W.; Werneth, Charles M.; Slaba, Tony C.; Badavi, Francis F.; Reddell, Brandon D.; Bahadori, Amir A.
2017-01-01
The current 3DHZETRN code has a detailed three dimensional (3D) treatment of neutron transport based on a forward/isotropic assumption and has been compared to Monte Carlo (MC) simulation codes in various geometries. In most cases, it has been found that 3DHZETRN agrees with the MC codes to the extent they agree with each other. However, a recent study of neutron leakage from finite geometries revealed that further improvements to the 3DHZETRN formalism are needed. In the present report, angular scattering corrections to the neutron fluence are provided in an attempt to improve fluence estimates from a uniform sphere. It is found that further developments in the nuclear production models are required to fully evaluate the impact of transport model updates. A model for the quasi-elastic neutron production spectra is therefore developed and implemented into 3DHZETRN.
EDS'09: 13th International Conference on Elastic & Diffractive Scattering
CERN. Geneva
2009-01-01
The series of International Conferences on Elastic and Diffractive Scattering was founded in 1985 in the picturesque old French town of Blois, famous for its XIV - XVIIth century château, inside of which the first meeting took place. Since then, meetings have been organised every two years in different places of the world: New York (1987), Evanston (1989), Isola d'Elba (1991), Providence (1993), Blois (1995), Seoul (1997), Protvino (1999), Prague (2001), Helsinki (2003), Blois (2005) and Hamburg (2007). The conference will focus on the most recent experimental and theoretical results in particle physics with an emphasis on Quantum Chromodynamics (QCD). http://cern.ch/eds09/ The conference agenda is now full. No further contributions can be accepted.
Scattering phase shift for elastic two pion scattering and the rho resonance in lattice QCD
Energy Technology Data Exchange (ETDEWEB)
Gutzwiller, Simone
2012-10-08
In this thesis we use lattice QCD to compute scattering phase shifts for elastic two-pion scattering in the isospin I=1 channel. Using Luescher's formalism, we derive the scattering phase shifts for different total momenta of the two-pion system in a non-rest frame. Furthermore we analyse the symmetries of the non-rest frame lattices and construct 2-pion and rho operators transforming in accordance with these symmetries. The data was collected for a 32{sup 3} x 64 and a 40{sup 3} x 64 lattice with N{sub f}=2 clover improved Wilson fermions at a pion mass around 290 MeV and a lattice spacing of about 0.072 fm.
Description of Elastic Scattering of Heavy Ions in the Glauber-Sitenko Approach
Lukyanov, V K; Chubov, Yu V
2001-01-01
In the framework of the Glauber-Sitenko approach, analytic expressions are derived for the amplitudes of elastic nucleus-nucleus scattering corresponding to different regimes of collision. An extended optical potential of the Woods Saxon type is employed in calculations, and the deviation of trajectories by a strong Coulomb field is taken into account. Comparison of the analytic evaluations of cross sections with the numerical results and experimental data show that the approach can be used in the energy region from 10 to 100 MeV/nucleon. In this way, at a given potential, one can find angular ranges where a definite picture of scattering like, for instance, the classical or rainbow scattering, the Fraunhofer or Fresnel diffraction takes place.
Differential Cross Sections for Neutron Elastic and Inelastic Scattering on 23Na
Directory of Open Access Journals (Sweden)
Vanhoy J.R.
2014-03-01
Full Text Available Measurements of neutron elastic and inelastic scattering from 23Na have been performed for sixteen incident neutron energies above 1.5 MeV with the 7-MV University of Kentucky Accelerator using the 3H(p,n reaction as the neutron source. These measurements were complemented by γ-ray excitation functions using the (n,n'γ reaction. The time-of-flight technique is employed for background reduction in both neutron and γ- ray measurements and for determining the energy of the scattered neutrons. Cross section determinations support fuel cycle and structural materials research and development. Previous reaction model evaluations [1] relied primarily on total cross sections and four (n,n0 and (n,n1 angular distributions in the En = 5 to 9 MeV range. The inclusion of more inelastic channels at lower neutron energies provides additional information on direct couplings between elastic and inelastic scattering as a function of angular momentum transfer. Reaction model calculations examining direct collective and statistical properties were performed.
Paneta, V.; Kokkoris, M.; Lagoyannis, A.; Preketes-Sigalas, K.
2017-09-01
The present work aims at contributing to the field of Ion Beam Analysis by providing a set of standard, high-accuracy nuclear resonance reaction data points to be used for accelerator energy calibration up to 4.6 MeV, more specifically with the use of the 27Al(p,γ), 13C(p,γ), 12C(p,p0) and 32S(p,p‧γ) resonant reactions, as a result of a comprehensive investigation in two different laboratories. The use of resonances at higher energies, namely up to 6 MeV, is also discussed. The measurements have been performed at two different electrostatic accelerators, namely at the 5.5 MV HV TN-11 of NCSR ;Demokritos;, Greece, and at the 5 MV 15SDH-2 Pelletron Tandem accelerator at Uppsala University in Uppsala, Sweden. Common points were used to normalize and validate the data. The possible use of the 16O(p,p0) resonance at 3.47 MeV is also discussed and analyzed.
Exchange nonlocal effects in the nuclear heavy-ion elastic scattering
Energy Technology Data Exchange (ETDEWEB)
Ribeiro, M.A.C.; Chamon, L.C.; Pereira, D. [Sao Paulo Univ., SP (Brazil). Inst. de Fisica; Galetti, D. [Instituto de Fisica Teorica (IFT), Sao Paulo, SP (Brazil)
1996-01-01
An interesting feature of the presence of exchange nonlocal effects in the nucleus-nucleus collision description in the modification of the nuclear barrier. This results, on the one hand, in an enhancement of the nuclear fusion cross sections due to the modification introduced in the basic quantum mechanical tunnelling calculation and, on the other hand, leads one to the study of the consequences of those effects in the nuclear elastic scattering. In this paper, we discuss the manifestations of the presence of those effects through an approximated model Schroedinger equation describing a nuclear system colliding at energies around the barrier. An an application, the elastic channel and, concomitantly, the fusion processes are studied for the {sup 16} O + {sup 60} Ni system at energies close to the barrier. (author). 15 refs., 4 figs.
The recoil proton polarization in. pi. p elastic scattering
Energy Technology Data Exchange (ETDEWEB)
Seftor, C.J.
1988-09-01
The polarization of the recoil proton for ..pi../sup +/p and ..pi../sup -/p elastic scattering has been measured for various angles at 547 MeV/c and 625 MeV/c by a collaboration involving The George Washington University; the University of California, Los Angeles; and Abilene Christian University. The experiment was performed at the P/sup 3/ East experimental area of the Los Alamos Meson Physics Facility. Beam intensities varied from 0.4 to 1.0 x 10/sup 7/ ..pi../sup -/'s/sec and from 3.0 to 10.0 x 10/sup 7/ ..pi../sup +/'s/sec. The beam spot size at the target was 1 cm in the horizontal direction by 2.5 cm in the vertical direction. A liquid-hydrogen target was used in a flask 5.7 cm in diameter and 10 cm high. The scattered pion and recoil proton were detected in coincidence using the Large Acceptance Spectrometer (LAS) to detect and momentum analyze the pions and the JANUS recoil proton polarimeter to detect and measure the polarization of the protons. Results from this experiment are compared with previous measurements of the polarization, with analyzing power data previously taken by this group, and to partial-wave analysis predictions. 12 refs., 53 figs., 18 tabs.
Nuclear isospin mixing and elastic parity-violating electron scattering
Energy Technology Data Exchange (ETDEWEB)
Moreno, O. [Instituto de Estructura de la Materia, CSIC, Serrano 123, E-28006 Madrid (Spain); Sarriguren, P. [Instituto de Estructura de la Materia, CSIC, Serrano 123, E-28006 Madrid (Spain)], E-mail: sarriguren@iem.cfmac.csic.es; Moya de Guerra, E.; Udias, J.M. [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, E-28040 Madrid (Spain); Donnelly, T.W. [Center for Theoretical Physics, Laboratory for Nuclear Science and Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Sick, I. [Departement fuer Physik, Universitaet Basel, CH-4056 Basel (Switzerland)
2009-09-15
The influence of nuclear isospin mixing on parity-violating elastic electron scattering is studied for the even-even, N=Z nuclei {sup 12}C, {sup 24}Mg, {sup 28}Si, and {sup 32}S. Their ground-state wave functions have been obtained using a self-consistent axially-symmetric mean-field approximation with density-dependent effective two-body Skyrme interactions. Some differences from previous shell-model calculations appear for the isovector Coulomb form factors which play a role in determining the parity-violating asymmetry. To gain an understanding of how these differences arise, the results have been expanded in a spherical harmonic oscillator basis. Results are obtained not only within the plane-wave Born approximation, but also using the distorted-wave Born approximation for comparison with potential future experimental studies of parity-violating electron scattering. To this end, for each nucleus the focus is placed on kinematic ranges where the signal (isospin-mixing effects on the parity-violating asymmetry) and the experimental figure-of-merit are maximized. Strangeness contributions to the asymmetry are also briefly discussed, since they and the isospin mixing contributions may play comparable roles for the nuclei being studied at the low momentum transfers of interest in the present work.
An in-vacuum diffractometer for resonant elastic soft x-ray scattering
Hawthorn, D. G.; He, F.; Davis, H.; Achkar, A. J.; Zhang, J.; Sutarto, R.; Wadati, H.; Radi, A.; Wilson, T.; Wright, G.; Shen, K. M.; Geck, J.; Zhang, H.; Novak, V.; Sawatzky, G. A.; Venema, L.C.
We describe the design, construction, and performance of a 4-circle in-vacuum diffractometer for resonant elastic soft x-ray scattering. The diffractometer, installed on the resonant elastic and inelastic x-ray scattering beamline at the Canadian Light Source, includes 9 in-vacuum motions driven by
Scholberg, Kate
2005-01-01
Rates of coherent neutrino-nucleus elastic scattering at a high-intensity stopped-pion neutrino source in various detector materials (relevant for novel low-threshold detectors) are calculated. Sensitivity of a coherent neutrino-nucleus elastic scattering experiment to new physics is also explored.
Elastic scattering and vibrational excitation for electron impact on para-benzoquinone
Jones, D. B.; Blanco, F.; García, G.; da Costa, R. F.; Kossoski, F.; Varella, M. T. do N.; Bettega, M. H. F.; Lima, M. A. P.; White, R. D.; Brunger, M. J.
2017-12-01
We report on theoretical elastic and experimental vibrational-excitation differential cross sections (DCSs) for electron scattering from para-benzoquinone (C6H4O2), in the intermediate energy range 15-50 eV. The calculations were conducted with two different theoretical methodologies, the Schwinger multichannel method with pseudopotentials (SMCPP) and the independent atom method with screening corrected additivity rule (IAM-SCAR) that also now incorporates a further interference (I) term. The SMCPP with N energetically open electronic states (Nopen) at the static-exchange-plus-polarisation (Nopench-SEP) level was used to calculate the scattering amplitudes using a channel coupling scheme that ranges from 1ch-SE up to the 89ch-SEP level of approximation. We found that in going from the 38ch-SEP to the 89ch-SEP, at all energies considered here, the elastic DCSs did not change significantly in terms of both their shapes and magnitudes. This is a good indication that our SMCPP 89ch-SEP elastic DCSs are converged with respect to the multichannel coupling effect for the investigated intermediate energies. While agreement between our IAM-SCAR+I and SMCPP 89ch-SEP computations improves as the incident electron energy increases from 15 eV, overall the level of accord is only marginal. This is particularly true at middle scattering angles, suggesting that our SCAR and interference corrections are failing somewhat for this molecule below 50 eV. We also report experimental DCS results, using a crossed-beam apparatus, for excitation of some of the unresolved ("hybrid") vibrational quanta (bands I-III) of para-benzoquinone. Those data were derived from electron energy loss spectra that were measured over a scattered electron angular range of 10°-90° and put on an absolute scale using our elastic SMCPP 89ch-SEP DCS results. The energy resolution of our measurements was ˜80 meV, which is why, at least in part, the observed vibrational features were only partially resolved. To
Positronium-alkali atom scattering at medium energies
Energy Technology Data Exchange (ETDEWEB)
Chakraborty, Ajoy [Laban Hrad Vidyapith, AD-369, Salt Lake City, Kolkata 700 064 (India); Basu, Arindam [Department of Physics, Maheshtala College, Chandannagar, South 24 Parganas, Kolkata 700 140 (India); Sarkar, Nirmal K [Sodepur Chandrachur Vidyapith, 1, Desh Bandhu Nagar, Sodepur, 743 174 (India); Sinha, Prabal K [Department of Physics, Bangabasi College, 19, Raj Kumar Chakravorty Sarani, Kolkata 700 009 (India)
2004-04-28
We investigate the scattering of orthopositronium (o-Ps) atom off different atomic alkali targets (Na to Cs) at low and medium energies (up to 120 eV). Projectile-elastic and target-elastic close-coupling models have been employed to investigate the systems in addition to the static-exchange model. Elastic, excitation and total cross sections have been reported for all four systems. The magnitude of the alkali excitation cross section increases with increasing atomic number of the target atom while the position of the peak value shifts towards lower incident energies. The magnitudes of the Ps excitation and ionization cross sections increase steadily with atomic number with no change in the peak position. The reported results show regular behaviour with increasing atomic number of the target atom. Scattering parameters for the Ps-Rb and Ps-Cs systems are being reported for the first time.
Elastic energy of polyhedral bilayer vesicles.
Haselwandter, Christoph A; Phillips, Rob
2011-06-01
In recent experiments [M. Dubois, B. Demé, T. Gulik-Krzywicki, J.-C. Dedieu, C. Vautrin, S. Désert, E. Perez, and T. Zemb, Nature (London) 411, 672 (2001)] the spontaneous formation of hollow bilayer vesicles with polyhedral symmetry has been observed. On the basis of the experimental phenomenology it was suggested [M. Dubois, V. Lizunov, A. Meister, T. Gulik-Krzywicki, J. M. Verbavatz, E. Perez, J. Zimmerberg, and T. Zemb, Proc. Natl. Acad. Sci. USA 101, 15082 (2004)] that the mechanism for the formation of bilayer polyhedra is minimization of elastic bending energy. Motivated by these experiments, we study the elastic bending energy of polyhedral bilayer vesicles. In agreement with experiments, and provided that excess amphiphiles exhibiting spontaneous curvature are present in sufficient quantity, we find that polyhedral bilayer vesicles can indeed be energetically favorable compared to spherical bilayer vesicles. Consistent with experimental observations we also find that the bending energy associated with the vertices of bilayer polyhedra can be locally reduced through the formation of pores. However, the stabilization of polyhedral bilayer vesicles over spherical bilayer vesicles relies crucially on molecular segregation of excess amphiphiles along the ridges rather than the vertices of bilayer polyhedra. Furthermore, our analysis implies that, contrary to what has been suggested on the basis of experiments, the icosahedron does not minimize elastic bending energy among arbitrary polyhedral shapes and sizes. Instead, we find that, for large polyhedron sizes, the snub dodecahedron and the snub cube both have lower total bending energies than the icosahedron.
Pion elastic and inelastic scattering from 51V at 180 MeV
Oakley, D. S.; Machuca, M. A.; Smithson, M. J.; Mordechai, S.; Moore, C. Fred; Seidl, P. A.; Morris, C. L.; Wang, Z. F.; Gilman, R.; Zumbro, J. D.; Fortune, H. T.; Seestrom-Morris, S. J.; Dhuga, K. S.; Watson, D. L.
1987-09-01
Differential cross sections were measured for pion elastic and inelastic scattering from 51V at Tπ=180 MeV. Elastic scattering data were analyzed using a standard Kisslinger potential. Inelastic scattering data were analyzed using distorted-wave impulse-approximation calculations with collective-model transition densities. Ground-state neutron-density parameters and matrix elements for some of the transitions were extracted.
Helicity in proton–proton elastic scattering and the spin structure of the pomeron
Directory of Open Access Journals (Sweden)
Carlo Ewerz
2016-12-01
Full Text Available We discuss different models for the spin structure of the nonperturbative pomeron: scalar, vector, and rank-2 symmetric tensor. The ratio of single-helicity-flip to helicity-conserving amplitudes in polarised high-energy proton–proton elastic scattering, known as the complex r5 parameter, is calculated for these models. We compare our results to experimental data from the STAR experiment. We show that the spin-0 (scalar pomeron model is clearly excluded by the data, while the vector pomeron is inconsistent with the rules of quantum field theory. The tensor pomeron is found to be perfectly consistent with the STAR data.
Elastic scattering of 9Be+51V near the Coulomb barrier
Directory of Open Access Journals (Sweden)
Morales-Rivera J.C.
2016-01-01
Full Text Available Elastic scattering angular distributions for the 9Be+51V system were measured at three near Coulomb barrier energies, Elab = 16.35, 17.44 and 18.53 MeV. The data were analyzed by using a Semimicroscopic Optical Model. This combines a microscopic calculation of the mean-field double folding potential and a phenomenological construction of the dynamical polarization potential. The calculations reproduced the data very well and the total reaction cross sections were also calculated.
Systematic analysis of α elastic scattering with the São Paulo potential
Energy Technology Data Exchange (ETDEWEB)
Charry-Pastrana, F. E., E-mail: feecharrypa@unal.edu.co; Pinilla, E. C. [Universidad Nacional de Colombia, Sede Bogotá, Facultad de Ciencias, Departamento de Física, Grupo de Física Nuclear, Carrera 45 No. 26-85, Edificio Uriel Gutiérrez, Bogotá D.C., Código Postal 111321 (Colombia)
2016-07-07
We describe systematically by collision energy and target mass, alpha elastic scattering angular distributions by using the São Paulo potential as the real part of the optical potential. The imaginary part is proportional to the real one by a factor N{sub i}. We find this parameter by fitting the theoretical angular distributions to the experimental cross sections through a χ{sup 2} minimization. The N{sub i} and their respective uncertainties, σ{sub Ni}, fall in the range 0.4 ≤ N{sub i} ± σ{sub N{sub i}} ≤ 0.8 for all the systems studied.
Elastic scattering measurements for {sup 7}Be+{sup 27}Al system at RIBRAS facility
Energy Technology Data Exchange (ETDEWEB)
Morcelle, V. [Instituto de Fisica - Universidade Federal Fluminense, 24210-346, Rio de Janeiro (Brazil) and Depto de Fisica Nuclear, Universidade de Sao Paulo, C.P. 66318, 05389-970, Sao Paulo (Brazil); Lichtenthaeler, R.; Morais, M. C.; Lepine-Szily, A.; Guimaraes, V.; Faria, P. N. de; Gasques, L.; Pires, K. C. C.; Condori, R. P. [Depto de Fisica Nuclear, Universidade de Sao Paulo, C. P. 66318, 05389-970, Sao Paulo (Brazil); Gomes, P. R. S.; Lubian, J.; Mendes, D. R. Jr. [Instituto de Fisica - Universidade Federal Fluminense, 24210-346, Rio de Janeiro (Brazil); Barioni, A. [Instituto de Fisica, Universidade Federal da Bahia, 40210-340, Bahia (Brazil); Shorto, J. M. B. [Instituto de Pesquisas Energeticas e Nucleares- IPEN, 05508-000, Sao Paulo (Brazil); Zamora, J. C. [Departament of Physics, Technische Universitaet Darmstadt (Germany)
2013-05-06
Elastic scattering angular distribution measurements of {sup 7}Be+{sup 27}Al system were performed at the laboratory energy of 15.6 MeV. The {sup 7}Be secondary beam was produced by the proton transfer reaction {sup 3}He({sup 6}Li,{sup 7}Be) and impinged on {sup 27}Al and {sup 197}Au targets, using the Radioactive Ion Beam (RIB) facility, RIBRAS. The elastic angular distribution was obtained within the angular range of 15{sup 0} - 80{sup 0} at the center of mass frame. Optical model calculations have been performed using the Woods- Saxon form factors and the Sao Paulo potential to fit the experimental data. The total reaction cross section was derived.
Portable bacterial identification system based on elastic light scatter patterns.
Bae, Euiwon; Ying, Dawei; Kramer, Donald; Patsekin, Valery; Rajwa, Bartek; Holdman, Cheryl; Sturgis, Jennifer; Davisson, V Jo; Robinson, J Paul
2012-08-28
Conventional diagnosis and identification of bacteria requires shipment of samples to a laboratory for genetic and biochemical analysis. This process can take days and imposes significant delay to action in situations where timely intervention can save lives and reduce associated costs. To enable faster response to an outbreak, a low-cost, small-footprint, portable microbial-identification instrument using forward scatterometry has been developed. This device, weighing 9 lb and measuring 12 × 6 × 10.5 in., utilizes elastic light scatter (ELS) patterns to accurately capture bacterial colony characteristics and delivers the classification results via wireless access. The overall system consists of two CCD cameras, one rotational and one translational stage, and a 635-nm laser diode. Various software algorithms such as Hough transform, 2-D geometric moments, and the traveling salesman problem (TSP) have been implemented to provide colony count and circularity, centering process, and minimized travel time among colonies. Experiments were conducted with four bacteria genera using pure and mixed plate and as proof of principle a field test was conducted in four different locations where the average classification rate ranged between 95 and 100%.
Portable bacterial identification system based on elastic light scatter patterns
Directory of Open Access Journals (Sweden)
Bae Euiwon
2012-08-01
Full Text Available Abstract Background Conventional diagnosis and identification of bacteria requires shipment of samples to a laboratory for genetic and biochemical analysis. This process can take days and imposes significant delay to action in situations where timely intervention can save lives and reduce associated costs. To enable faster response to an outbreak, a low-cost, small-footprint, portable microbial-identification instrument using forward scatterometry has been developed. Results This device, weighing 9 lb and measuring 12 × 6 × 10.5 in., utilizes elastic light scatter (ELS patterns to accurately capture bacterial colony characteristics and delivers the classification results via wireless access. The overall system consists of two CCD cameras, one rotational and one translational stage, and a 635-nm laser diode. Various software algorithms such as Hough transform, 2-D geometric moments, and the traveling salesman problem (TSP have been implemented to provide colony count and circularity, centering process, and minimized travel time among colonies. Conclusions Experiments were conducted with four bacteria genera using pure and mixed plate and as proof of principle a field test was conducted in four different locations where the average classification rate ranged between 95 and 100%.
Characterization of high-k dielectrics using MeV elastic scattering of He ions
Energy Technology Data Exchange (ETDEWEB)
Zoller, C.J. [Dept. of Physics and Astronomy, Ion Physics, Uppsala University, P.O. Box 516, SE 751 20 Uppsala (Sweden); Dentoni Litta, E. [KTH Royal Institute of Technology, School of ICT, Isafjordsgatan 22, SE 164 40 Kista (Sweden); Primetzhofer, D., E-mail: daniel.primetzhofer@physics.uu.se [Dept. of Physics and Astronomy, Ion Physics, Uppsala University, P.O. Box 516, SE 751 20 Uppsala (Sweden)
2015-03-15
We present a systematic comparison of two distinct ion-beam based methods for composition analysis of nanometer oxide films: ion-beam channeling and elastic scattering using nuclear resonances, both at MeV energies. Thin films of the technologically highly relevant high-k dielectrics HfO{sub 2} and HfAlO are characterized in the present study, with the additional aim of obtaining a better quantification of the Al content for the latter system. We show that both employed ion scattering methods enable a quantitative determination of the oxygen concentrations with typical uncertainties of about 5–10% in the oxygen fraction. The influence of various kinds of systematic inaccuracies in the evaluation procedure are discussed.
Low energy electron scattering from fuels
Energy Technology Data Exchange (ETDEWEB)
Lopes, M. Cristina A.; Silva, Daniel G.M.; Coelho, Rafael F.; Duque, Humberto V.; Santos, Rodrigo R. dos; Ribeiro, Thiago M. [Universidade Federal de Juiz de Fora (UFJF), MG (Brazil). Dept. de Fisica; Yates, Brent; Hong, Ling; Khakoo, Murtadha A. [California State University at Fullerton, CA (US). Physics Department; Bettega, Marcio H.F. [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Fisica; Costa, Romarly F. da [Universidade Federal do ABC (UFABC), Santo Andre, SP (Brazil). Centro de Ciencias Naturais e Humanas; Lima, Marco A.P. [Laboratorio Nacional de Ciencia e Tecnologia do Bioetanol (CTBE/CNPEM), Campinas, SP (Brazil)
2011-07-01
Full text. Accurate and precise values of absolute total cross section (TCS) represent important information in many scientific and technological applications. In our case, for example, we are motivated to provide such information for electron-fuel collision processes which are specifically relevant to modeling spark ignition in alcohol-fuelled internal combustion engines. Many electron scattering TCS measurements are presently available for a diverse range of atomic and molecular targets. However, lack of data for important bio-molecular targets still remains. Disagreements between the available TCS data for the alcohols have prompted several studies of electron scattering collision of slow electrons with these molecules which are currently important in applications as bio- fuels. This relevance, which has attracted much attention, has been one of the subjects of a recent collaboration between experimental and theoretical groups in the USA and Brazil. Recently this collaboration reported first measurements and calculations of differential cross sections for elastic low-energy (rotationally unresolved) electron scattering by several primary alcohols. In this work we address methanol and ethanol TCSs at low energy range and report additional studies of resonant structure in ethanol using the detection of metastable states produced by electron impact excitation with high energy resolution. We have recently constructed a TCS apparatus in our laboratory at Universidade Federal de Juiz de Fora, Brazil, based on the well-known linear transmission technique. The experimental setup is based on the measurement of the attenuation of a collimated electron beam through a gas cell containing the atoms or molecules to be studied at a given pressure. It consists essentially of an electron gun, a gas cell and an electron energy analyzer composed of an array of decelerating electrostatic lenses, a cylindrical dispersive 127o analyzer and a Faraday cup. To our knowledge, there exist
Elastic and inelastic neutron scattering cross sections for fission reactor applications
Energy Technology Data Exchange (ETDEWEB)
Hicks, S. F.; Combs, B.; Downes, L.; Girgis, J.; Kersting, L. J.; Lueck, C. J.; McDonough, P. J.; Schniederjan, J.; Sidwell, L.; Sigillito, A. J. [Department of Physics, University of Dallas, Irving TX 75019 (United States); Chakraborty, A.; Crider, B. P.; Kumar, A.; McEllistrem, M. T.; Peters, E. E.; Prados-Estevz, F. M. [Department of Physics and Astronomy, University of Kentucky, Lexington, KY 40506 (United States); Vanhoy, J. R.; Watts, D. [Department of Physics, United States Naval Academy, Annapolis MD 21402 (United States); Yates, S. W. [Department of Physics and Astronomy, University of Kentucky, Lexington, KY 40506 (United States) and Department of Chemistry, University of Kentucky, Lexington, KY 40506 (United States)
2013-04-19
Nuclear data important for the design and development of the next generation of light-water reactors and future fast reactors include neutron elastic and inelastic scattering cross sections on important structural materials, such as Fe, and on coolant materials, such as Na. These reaction probabilities are needed since neutron reactions impact fuel performance during irradiations and the overall efficiency of reactors. While neutron scattering cross sections from these materials are available for certain incident neutron energies, the fast neutron region, particularly above 2 MeV, has large gaps for which no measurements exist, or the existing uncertainties are large. Measurements have been made at the University of Kentucky Accelerator Laboratory to measure neutron scattering cross sections on both Fe and Na in the region where these gaps occur and to reduce the uncertainties on scattering from the ground state and first excited state of these nuclei. Results from measurements on Fe at incident neutron energies between 2 and 4 MeV will be presented and comparisons will be made to model calculations available from data evaluators.
El-Azab-Farid, M
2000-01-01
The differential cross sections of sup 6 sup , sup 7 Li elastic scattering from sup 1 sup 2 C, sup 2 sup 8 S, sup 4 sup 0 Ca, sup 5 sup 8 Ni, sup 9 sup 0 Zr and sup 2 sup 0 sup 8 Pb targets at E/A sub P =12.5 -53 MeV / u have been analyzed using density-independent double folding optical potentials. The calculations are built upon a very simple phenomenological nucleon-nucleon effective interaction, which is represented by a single Yukawa term with a complex strength. The complex microscopic potentials have successfully reproduced the elastic scattering data for most of the analyzed sets. However, more success has been obtained when the single Yukawa term was considered for the real part only while the imaginary part was formulated in a phenomenological Woods-Saxon form. The predictions of the calculated potentials are compared with those obtained by the phenomenological and the M3Y double folded optical potentials. The effects of the knock-on exchange contribution, the variation of the range of the interacti...
Spectral analysis of bistatic scattering from underwater elastic cylinders and spheres.
Gunderson, Aaron M; España, Aubrey L; Marston, Philip L
2017-07-01
Far field sound scattering from underwater elastic spheres and finite cylinders is considered over the full range of scattering angles. Three models for the frequency response of the scattered field are evaluated: a hybrid finite element/propagation simulation for a finite cylinder with broadside illumination, an approximate solution for the finite cylinder, and the exact solution for a sphere. The cylinder models are shown to give comparable results, attesting to the strength of the finite cylinder approximate solution. Interference and resonance structure present in the frequency response of the targets is identified and discussed, and the bistatic spectra for a variety of elastic sphere materials are presented. A thorough understanding of the complicated angle and frequency dependence of the scattering from simple elastic targets is helpful for interpretation of backscattering data from targets at or near an interface, or for scattering data taken by moving automated underwater vehicles, acoustic arrays, or other forms of data collection involving bistatic scattering.
Elastic and inelastic scattering in core and valence emission from solids: Some new directions
Fadley, Charles S.
1990-12-01
We review recent work from several groups that has led to some interesting new directions in the study of elastic and inelastic scattering of electrons in both core and valence x-ray photoemission (XPS) and core-initiated Auger emission from solids. The elastic diffraction of core photoelectrons as measured with high angular resolutions of approximately ±1° has been found for the example of c(2×2)S on Ni(001) to provide greater sensitivity to surface atomic structures, including interplanar relaxation in the Ni substrate. Both photoelectron diffraction and Auger electron diffraction have also recently been shown to have the potential for more direct structural determinations via holographic inversions of the data; so far, theoretical simulations have been carried out for c(2×2)S on Ni(001) and inversions of experimental data for Cu(001) and Cu(111) have also yielded encouraging results. The diffraction of inelastically scattered electrons has been found in recent work on Al(001), Ge(111), and W(110) to exhibit similar patterns to those of elastic electrons, but with significant reductions in intensity along low-index directions that can be explained by enhanced multiple scattering effects. The angular dependence of energy-integrated valence-band XPS spectra for Al(001) has furthermore been shown to provide further evidence for hole localization in the final state. This use of such spectra appears to depend on averaging over the entire Brillouin zone due to the effects of phonon-induced non-direct transitions and the analyzer angular acceptance. Finally, such zone-averaged valence spectra for AuCu3(001) have suggested a new method for estimating the atomic orbital makeup or partial densities of states of the initial valence states.
Ermisch, K; Amir-Ahmadi, HR; van den Berg, AM; Castelijns, R; Davids, B; Epelbaum, E; van Garderen, E; Glockle, W; Golak, J; Harakeh, MN; Hunyadi, M; de Huu, MA; Kalantar-Nayestanaki, N; Kamada, H; Kis, M; Mahjour-Shafiei, M; Nogga, A; Skibinski, R; Witala, H; Wortche, HJ
2003-01-01
To investigate the importance of three-nucleon forces (3NF) systematically over a broad range of intermediate energies, the differential cross sections of elastic proton-deuteron scattering have been measured at proton bombarding energies of 108, 120, 135, 150, 170, and 190 MeV at c.m. angles
Measurement of the analysing power in proton–proton elastic scattering at small angles
Directory of Open Access Journals (Sweden)
Z. Bagdasarian
2014-12-01
Full Text Available The proton analysing power in p→p elastic scattering has been measured at small angles at COSY-ANKE at 796 MeV and five other beam energies between 1.6 and 2.4 GeV using a polarised proton beam. The asymmetries obtained by detecting the fast proton in the ANKE forward detector or the slow recoil proton in a silicon tracking telescope are completely consistent. Although the analysing power results agree well with the many published data at 796 MeV, and also with the most recent partial wave solution at this energy, the ANKE data at the higher energies lie well above the predictions of this solution at small angles. An updated phase shift analysis that uses the ANKE results together with the World data leads to a much better description of these new measurements.
Angle-differential elastic electron scattering off Mn
Dolmatov, V. K.
2017-11-01
Angle-differential elastic electron-scattering cross section, d/σ d Ω , for a 20-eV electron collision with a half-filled-subshell Mn (...3 d54 s2,6S) atom is studied using a semiempirical static polarization potential of the atom in the calculations. The study is in order, primarily due to noticeable discrepancies between results of the only two existing experimental measurements of the differential cross section, as well as discrepancies between the experimental results and available theoretical data. The calculation of d/σ d Ω is performed in the framework of the spin-polarized Hartree-Fock approximation modified by the addition of the Bates static polarization potential Vpol(r ) into the equations. An element of the study is the utilization of individual static dipole polarizabilities, α4 s ↑ and α4 s ↓, of the 4 s electrons with opposite spin orientations (4 s ↑ and 4 s ↓ electrons) from the atomic 4 s2 subshell. They are calculated and used for the subsequent calculation of Vpol(r ) and, finally, d/σ d Ω . The utility of the model is proven by a good agreement between the results of a trial calculation of d/σ d Ω and corresponding trial calculated results obtained in the framework of a sophisticated random phase approximation with exchange. The results of the subsequent final calculation of d/σ d Ω are compared with the experimental data along with the available theoretical results obtained in the framework of a spin-polarized local density approximation. Renewed theoretical and experimental studies of the 20-eV d/σ d Ω of Mn are urged.
Measurement of Neutrino-Nucleon Neutral-Current Elastic Scattering Cross-section at SciBooNE
Energy Technology Data Exchange (ETDEWEB)
Takei, Hideyuki [Tokyo Inst. of Technology (Japan)
2009-02-01
In this thesis, results of neutrino-nucleon neutral current (NC) elastic scattering analysis are presented. Neutrinos interact with other particles only with weak force. Measurement of cross-section for neutrino-nucleon reactions at various neutrino energy are important for the study of nucleon structure. It also provides data to be used for beam flux monitor in neutrino oscillation experiments. The cross-section for neutrino-nucleon NC elastic scattering contains the axial vector form factor G_{A}(Q^{2}) as well as electromagnetic form factors unlike electromagnetic interaction. G_{A} is propotional to strange part of nucleon spin (Δs) in Q^{2} → 0 limit. Measurement of NC elastic cross-section with smaller Q^{2} enables us to access Δs. NC elastic cross-sections of neutrino-nucleon and antineutrino-nucleon were measured earlier by E734 experiment at Brookheaven National Laboratory (BNL) in 1987. In this experiment, cross-sections were measured in Q^{2} > 0.4 GeV^{2} region. Result from this experiment was the only published data for NC elastic scattering cross-section published before our experiment. SciBooNE is an experiment for the measurement of neutrino-nucleon scattering cross-secitons using Booster Neutrino Beam (BNB) at FNAL. BNB has energy peak at 0.7 GeV. In this energy region, NC elastic scattering, charged current elastic scattering, charged current pion production, and neutral current pion production are the major reaction branches. SciBar, electromagnetic calorimeter, and Muon Range Detector are the detectors for SciBooNE. The SciBar consists of finely segmented scintillators and 14336 channels of PMTs. It has a capability to reconstruct particle track longer than 8 cm and separate proton from muons and pions using energy deposit information. Signal of NC elastic scattering is a single proton track. In vp → vp process, the recoil proton is detected. On the other hand, most of vn → vn is
Liu, Fengming; Liu, Zhengyou
2015-10-23
We theoretically investigate elastic waves propagating in metamaterials with simultaneous zero indices for both the longitudinal and transverse waves. With scattering objects (here cylinders) present in the metamaterial slabs, while the elastic waves can mostly transmit through the metamaterial slabs perfectly, exhibiting the well-known cloaking effect of zero-index metamaterials, they nevertheless become totally blocked at resonances, indicating strong elastic wave scattering by the objects in the cases. However, despite the occurrence of the elastic wave scattering, there is, counterintuitively, no mode conversion between the longitudinal and transverse waves in the process, completely in contrast to that in conventional elastic media. A design of a two-dimensional phononic crystal with these peculiar properties is presented.
Koutsopoulos, S; van der Oost, J; Norde, W
2005-01-01
The dynamic behavior of an endoglucanase from the hyperthermophilic microorganism Pyrococcus furiosus was investigated using elastic neutron scattering. The temperature dependence of the atomic motions was correlated with conformational. and functional characteristics of the enzyme. The onset of
Backward-forward reaction asymmetry of neutron elastic scattering on deuterium
Pirovano, E.; Beyer, R.; Junghans, A. R.; Nankov, N.; Nolte, R.; Nyman, M.; Plompen, A. J. M.
2017-02-01
A new measurement of the angular distribution of neutron elastic scattering on deuterium was carried out at the neutron time-of-flight facility nELBE. The backward-forward asymmetry of the reaction was investigated via the direct detection of neutrons scattered at the laboratory angle of 15∘ and 165∘ from a polyethylene sample enriched with deuterium. In order to extend the measurement to neutron energies below 1 MeV, 6Li glass scintillators were employed. The data were corrected for the background and the multiple scattering in the target, the events due to scattering on deuterium were separated from those due to carbon, and the ratio of the differential cross section at 15∘ and 165∘ was determined. The results, covering the energy range from 200 keV to 2 MeV, were found to be in agreement with the theoretical predictions calculated by Canton et al. [Eur. Phys. J. A 14, 225 (2002)], 10.1140/epja/i2001-10122-3 and by Golak et al. [Eur. Phys. J. A 50, 177 (2014)], 10.1140/epja/i2014-14177-7. The comparison with the evaluated nuclear data libraries indicated CENDL-3.1, JEFF-3.2, and JENDL-4.0 as the evaluations that best describe the asymmetry of n -d scattering. ENDF/B-VII.1 is compatible with the data for energies below 700 keV, but above the backward to forward ratio is higher than measured. ROSFOND-2010 and BROND-2.2 resulted to have little compatibility with the data.
Analytic description of elastic electron-atom scattering in an elliptically polarized laser field
Flegel, A. V.; Frolov, M. V.; Manakov, N. L.; Starace, Anthony F.; Zheltukhin, A. N.
2013-01-01
An analytic description of laser-assisted electron-atom scattering (LAES) in an elliptically polarized field is presented using time-dependent effective range (TDER) theory to treat both electron-laser and electron-atom interactions nonperturbatively. Closed-form formulas describing plateau features in LAES spectra are derived quantum mechanically in the low-frequency limit. These formulas provide an analytic explanation for key features of the LAES differential cross section. For the low-energy region of the LAES spectrum, our result generalizes the Kroll-Watson formula to the case of elliptic polarization. For the high-energy (rescattering) plateau in the LAES spectrum, our result generalizes prior results for a linearly polarized field valid for the high-energy end of the rescattering plateau [Flegel , J. Phys. BJPAPEH0953-407510.1088/0953-4075/42/24/241002 42, 241002 (2009)] and confirms the factorization of the LAES cross section into three factors: two field-free elastic electron-atom scattering cross sections (with laser-modified momenta) and a laser field-dependent factor (insensitive to the scattering potential) describing the laser-driven motion of the electron in the elliptically polarized field. We present also approximate analytic expressions for the exact TDER LAES amplitude that are valid over the entire rescattering plateau and reduce to the three-factor form in the plateau cutoff region. The theory is illustrated for the cases of e-H scattering in a CO2-laser field and e-F scattering in a midinfrared laser field of wavelength λ=3.5μm, for which the analytic results are shown to be in good agreement with exact numerical TDER results.
Low-lying non-normal parity states in 8B measured by proton elastic scattering on 7Be
Yamaguchi, H; Wakabayashi, Y.; Kubono, S.; Amadio, G; Fujikawa, H; Teranishi, T.; Saito, A; He, J. J.; Nishimura, S; Togano, Y.; Y.K. Kwon; Niikura, M; Iwasa, N.; Inafuku, K.; Khiem, L. H.
2008-01-01
A new measurement of proton resonance scattering on 7Be was performed up to the center-of-mass energy of 6.7 MeV using the low-energy RI beam facility CRIB (CNS Radioactive Ion Beam separator) at the Center for Nuclear Study of the University of Tokyo. The excitation function of 7Be+p elastic scattering above 3.5 MeV was measured successfully for the first time, providing important information about the resonance structure of the 8B nucleus. The resonances are related to the reaction rate of ...
Diffraction model analysis of pion-12C elastic scattering at 800 MeV ...
Indian Academy of Sciences (India)
Elastic scattering of 800 MeV/c pions by 12C has been studied in the diffraction model with a view to determine pion optical potential by the method of inversion. Finding an earlier diffraction model analysis to be deficient in some respects, we propose a Glauber model based parametrization for the elastic -matrix and show ...
Measurements on small angle elastic scattering from p p and anti-p p collisions at the ISR
Shukla, Shekhar
1986-01-01
Experiment R211 was performed at the Intersecting Storage rings (ISR) of the European Center for Nuclear Research (CERN), Geneva, Switzerland. The aim was to measure, for pp and anti-p(p) scattering at high energy, the three quantities: (1) the total nuclear cross section, σ/sub n/, (2) the nuclear slope parameter, b, that describes the dependence of the differential elastic cross section on the 4- momentum transfer, t, for small absolute value of t, and (3) the ratio, rho, of the real to the imaginary part of the forward nuclear elastic scattering amplitude. These quantities were deduced from differential elastic scattering cross sections measured in the near forward direction. The measurements were made for pp scattering at √s = 30.5 GeV, 52.8 GeV and 62.5 GeV. The total cross section for both pp and anti-p(p) scattering is seen to rise in the range √s = 30.5 GeV to √s = 62.5 GeV. The rise is consistent with an asymptotic increase of σ/sub n/ as In2(s/s0), the highest rate allowed by the Froissart b...
Analysis of 11Be + p elastic scattering using a BHF approach
Sharma, Manjari; Haider, W.; Bhagwat, A.
2017-10-01
The elastic scattering of the halo nucleus 11Be on the proton at various incident energies has been analysed using the microscopic optical potential (OP) calculated within the first order non-relativistic Brueckner-Hartree-Fock (BHF) approach. Argonne v-18 inter-nucleon potential is employed to calculate the microscopic OP. The nuclear density distribution has been obtained using a semi-phenomenological model. The density used shows extended neutron distribution indicating a possible halo structure. We have also compared our results with an empirical analysis using CH89 global OP. The analysis reveals that the BHF approach provides good agreement with the experimental data for all incident energies considered in this paper.
Microscopic study of {sup 6}He elastic scattering around the Coulomb barrier
Energy Technology Data Exchange (ETDEWEB)
Descouvemont, P. [Physique Nucléaire Théorique et Physique Mathématique, C.P. 229, Université Libre de Bruxelles (ULB), B 1050 Brussels (Belgium)
2016-07-07
We investigate {sup 6}He scattering on {sup 27}Al, {sup 58}Ni, {sup 120}Sn, and {sup 208}Pb in a microscopic version of the Continuum Discretized Coupled Channel (CDCC) method. We essentially focus on energies around the Coulomb barrier. The {sup 6}He nucleus is described by an antisymmetric 6-nucleon wave function, defined in the Resonating Group Method. The {sup 6}He continuum is simulated by square-integrable positive-energy states. The model does not depend on any adjustable parameter as it is based only on well known nucleon-target potentials. We show that experimental elastic cross sections are fairly well reproduced. The calculation suggests that breakup effects increase for high target masses. For a light system such as {sup 6}He+{sup 27}Al, breakup effects are small, and a single-channel approximation provides fair results.
Ramírez Suárez, O. L.; Sparenberg, J.-M.
2017-09-01
We introduce a simplified effective-range function for charged nuclei, related to the modified K matrix but differing from it in several respects. Negative-energy zeros of this function correspond to bound states. Positive-energy zeros correspond to resonances and "echo poles" appearing in elastic-scattering phase-shifts, while its poles correspond to multiple-of-π phase shifts. Padé expansions of this function allow one to parametrize phase shifts on large energy ranges and to calculate resonance and bound-state properties in a very simple way, independently of any potential model. The method is first tested on a d -wave 12C+α potential model. It is shown to lead to a correct estimate of the subthreshold-bound-state asymptotic normalization constant (ANC) starting from the elastic-scattering phase shifts only. Next, the 12C+α experimental p -wave and d -wave phase shifts are analyzed. For the d wave, the relatively large error bars on the phase shifts do not allow one to improve the ANC estimate with respect to existing methods. For the p wave, a value agreeing with the 12C(6Li,d )16O transfer-reaction measurement and with the recent remeasurement of the 16Nβ -delayed α decay is obtained, with improved accuracy. However, the method displays two difficulties: the results are sensitive to the Padé-expansion order and the simplest fits correspond to an imaginary ANC, i.e., to a negative-energy "echo pole," the physical meaning of which is still debatable.
Spectroscopic information of 6Li from elastic scattering of deuterons, 3He and 4He by 6Li
Amar, A.
2014-07-01
The elastic scattering of deuterons, 3He and 4He on 6Li at different incident energies have been analyzed in the framework of the optical model (OM) using ECIS88 as well as SPI GENOA codes. The optical potential parameters were extracted in the phenomenological treatment. A good agreement between theoretical and experimental differential cross-sections was obtained in whole angular range. Parameters for real part of potential have been also calculated microscopically with double-folding model for the d, 3He and 4He scattering, respectively, using DFPOT code. The elastic transfer mechanism has been studied by coupled reaction channel (CRC) method using FRESCO code. Spectroscopic amplitudes of 6Li ≡ t + 3He and 6Li ≡ α + d configurations have been extracted from d, 3He and 4He scattering on 6Li at wide energy range. A comparison between spectroscopic amplitudes obtained from deuteron and α elastically scattering from 6Li has been made. The extracted spectroscopic amplitudes of 6Li ≡ 4He + d(SF = SA2) from 6Li(d, 6Li)d and 6Li(α, 6Li)α are not the same as expected theoretically.
Power spectral density of the heterogeneous fracture compliance from scattered elastic wavefields
Minato, S.; Ghose, R.
2014-01-01
Using the scattered elastic wavefield, a method to derive the power spectral density (PSD) of the heterogeneous compliance distribution, along the plane of a single fracture, is formulated. The method involves estimation of the stress field at the fracture depth from the scattered wavefield followed
Energy Technology Data Exchange (ETDEWEB)
Fagundes, Daniel Almeida
2010-07-01
The theoretical description of high-energy elastic hadron scattering constitutes an open problem in both, the underlying quantum field theory of strong interactions (QCD) and the phenomenological context. In this work the inverse problem in elastic hadron scattering is discussed in the impact parameter and eikonal frameworks, specifically a study on the empirical extraction of the profile, the inelastic overlap and the eikonal functions, from the experimental data and some principles and high-energy theorems (model independent). The analysis is limited to elastic proton-proton scattering in the center of momentum energy interval 19.4 - 62.5 GeV. In particular, a novel representation for the Martin's Real Part Formula is introduced but without the scaling property and suitable for empirical analysis. By means of this representation, and two other parametrizations previously introduced (constrained and unconstrained), several properties of the inelastic overlap function and the imaginary part of the eikonal (opacity) in the momentum transfer space are determined, in special: (1) evidence of a peripheral effect (tail) in the inelastic overlap function in the parameter impact space above 2 fm; (2) development of analytical parametrizations for this function leading to three gaussian components with centers at 0.0, {approx}0.7 and {approx}1.3 fm; (3) evidence of a finite zero (change of sign) in the opacity function in the momentum transfer space; (4) development of empirical parametrization for this function consistent with form factors as a product of two monopoles with constrained masses (not a dipole type) and a term with zero; (5) detailed discussion on the determination of the opacity function in the momentum transfer space through the semi-analytical approach. The applicability of these empirical results in the development of eikonal models (mainly those inspired in QCD) is also discussed. (author)
Energy Technology Data Exchange (ETDEWEB)
Salas, E.; Jimenez-Villacorta, F.; Jimenez Rioboo, R.J.; Prieto, C. [Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Cientificas, Cantoblanco, 28049 Madrid (Spain); Sanchez-Marcos, J. [Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Cientificas, Cantoblanco, 28049 Madrid (Spain); Departamento de Quimica-Fisica Aplicada, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Munoz-Martin, A.; Prieto, J.E.; Joco, V. [Centro de Microanalisis de Materiales, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain)
2013-03-15
Surface acoustic wave (SAW) velocity has been determined by high resolution Brillouin light scattering to study the mechano-elastic properties of boron carbide films prepared by radio frequency (RF) sputtering. The comparison of experimentally observed elastic behaviour with simulations made by considering film composition obtained from elastic recoil detection analysis-time of flight (ERDA-ToF) spectroscopy allows establishing that elastic properties are determined by that of crystalline boron carbide with a lessening of the SAW velocity values due to surface oxidation. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Single spin asymmetry AN in polarized proton–proton elastic scattering √s=200 GeV
Adamczyk, L.; Agakishiev, G.; La Pointe, S.L.; Zyzak, M.
2013-01-01
We report a high precision measurement of the transverse single spin asymmetry AN at the center of mass energy √s = 200 GeV in elastic proton–proton scattering by the STAR experiment at RHIC. The AN was measured in the four-momentum transfer squared t range 0.003 |t| 0.035 (GeV/c)2, the region of a
Energy Technology Data Exchange (ETDEWEB)
Magazù, S.; Migliardo, F. [Dipartimento di Fisica e di Scienze della Terra dell’, Università degli Studi di Messina, Viale F. S. D’Alcontres 31, 98166 Messina (Italy); Vertessy, B.G. [Institute of Enzymology, Hungarian Academy of Science, Budapest (Hungary); Caccamo, M.T., E-mail: maccamo@unime.it [Dipartimento di Fisica e di Scienze della Terra dell’, Università degli Studi di Messina, Viale F. S. D’Alcontres 31, 98166 Messina (Italy)
2013-10-16
Highlights: • Innovative multiresolution wavelet analysis of elastic incoherent neutron scattering. • Elastic Incoherent Neutron Scattering measurements on homologues disaccharides. • EINS wavevector analysis. • EINS temperature analysis. - Abstract: In the present paper the results of a wavevector and thermal analysis of Elastic Incoherent Neutron Scattering (EINS) data collected on water mixtures of three homologous disaccharides through a wavelet approach are reported. The wavelet analysis allows to compare both the spatial properties of the three systems in the wavevector range of Q = 0.27 Å{sup −1} ÷ 4.27 Å{sup −1}. It emerges that, differently from previous analyses, for trehalose the scalograms are constantly lower and sharper in respect to maltose and sucrose, giving rise to a global spectral density along the wavevector range markedly less extended. As far as the thermal analysis is concerned, the global scattered intensity profiles suggest a higher thermal restrain of trehalose in respect to the other two homologous disaccharides.
Serpentine locomotion through elastic energy release
Movchan, N. V.
2017-01-01
A model for serpentine locomotion is derived from a novel perspective based on concepts from configurational mechanics. The motion is realized through the release of the elastic energy of a deformable rod, sliding inside a frictionless channel, which represents a snake moving against lateral restraints. A new formulation is presented, correcting previous results and including situations never analysed so far, as in the cases when the serpent's body lies only partially inside the restraining channel or when the body has a muscle relaxation localized in a small zone. Micromechanical considerations show that propulsion is the result of reactions tangential to the frictionless constraint and acting on the snake's body, a counter-intuitive feature in mechanics. It is also experimentally demonstrated that the propulsive force driving serpentine motion can be directly measured on a designed apparatus in which flexible bars sweep a frictionless channel. Experiments fully confirm the theoretical modelling, so that the presented results open the way to exploration of effects, such as variability in the bending stiffness or channel geometry or friction, on the propulsive force of snake models made up of elastic rods. PMID:28566512
Magnetoconductivity of quantum wires with elastic and inelastic scattering
DEFF Research Database (Denmark)
Bruus, Henrik; Flensberg, Karsten; Smith
1993-01-01
function describing the occupation of these single-particle states satisfies a Boltzmann equation, which may be solved exactly in the case of impurity scattering. In the case where the electrons scatter against both phonons and impurities we solve numerically—and in certain limits analytically—the integral...
Spin-Momentum Correlations in Quasi-Elastic Electron Scattering from Deuterium
Passchier, I; Szczerba, D; Alarcon, R; Bauer, T S; Boersma, D J; Van den Brand, J F J; Bulten, H J; Ent, R; Ferro-Luzzi, M; Harvey, M; Heimberg, P; Higinbotham, D W; Klous, S; Kolster, H; Lang, J; Militsyn, B L; Nikolenko, D M; Nooren, G J L; Norum, B E; Poolman, H R; Rachek, Igor A; Simani, M C; Six, E; De Vries, H; Wang, K; Zhou, Z L; Bauer, Th.S.
2002-01-01
We report on a measurement of spin-momentum correlations in quasi-elastic scattering of longitudinally polarized electrons with an energy of 720 MeV from vector-polarized deuterium. The spin correlation parameter $A^V_{ed}$ was measured for the $^2 \\vec{\\rm H}(\\vec e,e^\\prime p)n$ reaction for missing momenta up to 350 MeV/$c$ at a four-momentum transfer squared of 0.21 (GeV/c)$^2$. The data give detailed information about the spin structure of the deuteron, and are in good agreement with the predictions of microscopic calculations based on realistic nucleon-nucleon potentials and including various spin-dependent reaction mechanism effects. The experiment demonstrates in a most direct manner the effects of the D-state in the deuteron ground-state wave function and shows the importance of isobar configurations for this reaction.
alpha. -transfer contribution to sup 9 Be+ sup 13 C elastic and inelastic scattering
Energy Technology Data Exchange (ETDEWEB)
Barbadoro, A.; Pellegrini, F.; Segato, G.F.; Taffara, L. (Dipartimento di Fisica dell' Universita, Padova (Italy) Sezione di Padova, Istituto Nazionale di Fisica Nucleare, Padova (Italy)); Gabrielli, I. (Dipartimento di Fisica dell' Universita, Trieste (Italy) Sezione di Trieste, Istituto Nazionale di Fisica Nucleare, Trieste (Italy)); Bruno, M. (Dipartimento di Fisica dell' Universita, Bologna (Italy) Sezione di Bologna, Istituto Nazionale di Fisica Nucleare, Bologna (Italy))
1990-05-01
Angular distributions for the {sup 9}Be+{sup 13}C elastic and inelastic scattering have been measured at a {sup 9}Be bombarding energy of 50.46 MeV over an angular range from 10{degree} to 170{degree} c.m. Besides the ground state of {sup 13}C, the 3.68 MeV {ital J}{sup {pi}}=3/2{sup {minus}} and the 7.55 MeV {ital J}{sup {pi}}=5/2{sup {minus}} levels are strongly populated. The enhancement of the backward cross section is clear evidence that the process is dominated by the exchange of an {alpha} particle between two identical {sup 9}Be cores. The experimental relative integrated cross sections are fairly well reproduced by distorted wave calculations using an {alpha}-cluster form factor and the shell-model spectroscopic strengths of Kurath.
Proton resonance elastic scattering of $^{30}$Mg for single particle structure of $^{31}$Mg
The single particle structure of $^{31}$Mg, which is located in the so-called “island of inversion”, will be studied through measuring Isobaric Analog Resonances (IARs) of bound states of $^{31}$Mg. They are located in the high excitation energy of $^{31}$Al. We are going to determine the spectroscopic factors and angular momenta of the parent states by measuring the excitation function of the proton resonance elastic scattering around 0 degrees in the laboratory frame with around 3 MeV/nucleon $^{30}$Mg beam. The present study will reveal the shell evolution around $^{32}$Mg. In addition, the spectroscopic factor of the (7/2)$^{−}$ state which was not yet determined experimentally, may allow one to study the shape coexistence in this nucleus.
Energy Technology Data Exchange (ETDEWEB)
Zamora, J.C.; Barioni, A.; Guimaraes, V. [Universidade de Sao Paulo (USP), SP (Brazil); Paes, B.; Lubian, J. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil); Aguilera, E.F. [Instituto Nacional de Investigaciones Nucleares (Mexico); Kolata, J.J.; Roberts, A.L. [University of Notre Dame, Indiana (United States); Becchetti, F.D.; Villano, A.; Ojaruega, M.; Jing, H. [University of Michigan (United States)
2011-07-01
In this work we have measured angular distributions for the elastic scattering of {sup 8}B, {sup 7}Be and {sup 6}Li on {sup 12}C target at laboratory energies of 25.8 MeV, 18.8 MeV and 12.3 MeV, respectively. The optical model has been used for the analysis of such data using Woods-Saxon and Sao Paulo potentials. We also probed the effect of breakup on the elastic scattering of {sup 8}B+{sup 12}C as this mechanism may become important due to the low binding energy of this nucleus. This investigation was performed by means of coupled channels calculations and cluster folding potentials. This study is very interesting because there are few data on {sup 8}B elastic scattering. There are some of its elastic scattering on carbon target, but at higher energies, where it was not possible to get information on its halo peculiarities. Also, we present here the total reaction cross section obtained from the elastic scattering analysis and compared with other weakly and tightly bound projectiles on carbon target. (author)
Directory of Open Access Journals (Sweden)
Pacheco de Carvalho, J. A.
2008-08-01
Full Text Available This article involves computer simulation and surface analysis by nuclear techniques, which are non-destructive. Both the “energy method of analysis” for nuclear reactions and elastic scattering are used. Energy spectra are computer simulated and compared with experimental data, giving target composition and concentration profile information. The method is successfully applied to thick flat targets of graphite, quartz and sapphire and targets containing thin films of aluminium oxide. Depth profiles of ^{12}C and ^{16}O nuclei are determined using (d,p and (d,α deuteron induced reactions. Rutherford and resonance elastic scattering of (^{4}He+ ions are also used.
Este artículo trata de simulación por ordenador y del análisis de superficies mediante técnicas nucleares, que son no destructivas. Se usa el “método de análisis en energia” para reacciones nucleares, así como el de difusión elástica. Se simulan en ordenador espectros en energía que se comparan com datos experimentales, de lo que resulta la obención de información sobre la composición y los perfiles de concentración de la muestra. Este método se aplica con éxito em muestras espesas y planas de grafito, cuarzo y zafiro y muestras conteniendo películas finas de óxido de aluminio. Se calculan perfiles en profundidad de núcleos de ^{12}C y de ^{16}O a través de reacciones (d,p y (d,α inducidas por deuterones. Se utiliza también la difusión elástica de iones (^{4}He+, tanto a Rutherford como resonante.
Energy Technology Data Exchange (ETDEWEB)
Gauron, Pierre; Basarab Nicolescu [Theoretical Physics Division, Inst. de Physique Nucleaire, Paris-11 Univ., 91 - Orsay (France); Selyugin, O.V. [Lab. of Theoretical Physics, Joint Inst. for Nuclear Research, Dubna (Russian Federation)
1999-10-01
It is shown that the measurement of the polarization together with the hadron elastic dN/dt distribution of the Coulomb nuclei interference region allows to extract directly from the data both the real and imaginary parts of the spin-non-flip nuclear amplitude independently of each other and without any arbitrary theoretical assumption. The crucial parameter {rho} = ReF/ImF will be therefore known as a function of t at fixed s and will allow us to detect new phenomena in hadron physics. (authors)
Backward elastic light scattering of malaria infected red blood cells
Lee, Seungjun; Lu, Wei
2011-08-01
We investigated the backward light scattering pattern of healthy and malaria (Plasmodium falciparum) parasitized red blood cells. The spectrum could clearly distinguish between predominant ring stage infected blood cells and healthy blood cells. Further, we found that infected samples mixed with different stages of P. falciparum showed different signals, suggesting that even variance in parasite stages could also be detected by the spectrum. These results together with the backward scattering technique suggest the potential of non-invasive diagnosis of malaria through light scattering of blood cells near the surface of human body, such as using eyes or skin surface.
Energy Technology Data Exchange (ETDEWEB)
Adams, D.; Adeva, B.; Akdogan, T.; Arik, E.; Arvidson, A.; Badelek, B; Bardin, G.; Baum, G.; Berglund, P.; Betev, L.; Birsa, R.; Bjoerkholm, P.; Bonner, B.E.; Botton, N. de E-mail: nico.de.botton@cern.ch; Boutemeur, M.; Bradamante, F.; Bravar, A.; Bressan, A.; Bueltmann, S.; Burtin, E.; Cavata, C.; Clocchiatti, M.; Crabb, D.; Cranshaw, J.; Cuhadar, T.; Dalla Torre, S.; Dantzig, R. van; Derro, B.; Deshpande, A.; Dhawan, S.; Dulya, C.; Dyring, A.; Eichblatt, S.; Faivre, J.C.; Fasching, D.; Feinstein, F.; Fernandez, C.; Forthmann, S.; Frois, B.; Gallas, A.; Garzon, J.A.; Gatignon, L.; Gaussiran, T.; Gilly, H.; Giorgi, M.; Goeler, E. von; Goertz, S.; Golutvin, I.A.; Gracia, G.; Groot, N. de; Grosse Perdekamp, M.; Haft, K.; Harrach, D. von; Hasegawa, T.; Hautle, P.; Hayashi, N.; Heusch, C.A.; Horikawa, N.; Hughes, V.W.; Igo, G.; Ishimoto, S.; Iwata, T.; Kabuss, E.M.; Kageya, T.; Karev, A.; Kessler, H.J.; Ketel, T.J.; Kiryluk, J.; Kiryushin, I.; Kishi, A.; Kisselev, Yu.; Klostermann, L.; Kraemer, D.; Krivokhijine, V.; Kroeger, W.; Kukhtin, V.; Kurek, K.; Kyynaeraeinen, J.; Lamanna, M.; Landgraf, U.; Le Goff, J.M.; Lehar, F.; Lesquen, A. de; Lichtenstadt, J.; Lindqvist, T.; Litmaath, M.; Lowe, M.; Magnon, A.; Mallot, G.K.; Marie, F.; Martin, A.; Martino, J.; Matsuda, T.; Mayes, B.; McCarthy, J.S.; Medved, K.; Meyer, W.; Middelkoop, G. van; Miller, D.; Miyachi, Y.; Mori, K.; Moromisato, J.; Nagaitsev, A.; Nassalski, J.; Naumann, L.; Niinikoski, T.O.; Oberski, J.E.J.; Ogawa, A.; Ozben, C.; Pereira, H.; Perrot-Kunne, F.; Peshekhonov, D.; Piegaia, R.; Pinsky, L.; Platchkov, S.; Plo, M.; Pose, D.; Postma, H.; Pretz, J.; Pussieux, T.; Raedel, G.; Rijllart, A.; Reicherz, G.; Roberts, J.B.; Rock, S.; Rodriguez, M.; Rondio, E.; Ropelewski, L.; Sabo, I.; Saborido, J.; Sandacz, A; Savin, I.; Schiavon, P.; Schiller, A.; Schueler, K.P.; Seitz, R.; Semertzidis, Y.; Sergeev, S.; Shanahan, P.; Sichtermann, E.P.; Simeoni, F.; Smirnov, G.I.; Staude, A.; Steinmetz, A. [and others
2000-03-21
A muon beam polarimeter was built for the SMC experiment at the CERN SPS, for beam energies of 100 and 190 GeV. The beam polarisation is determined from the asymmetry in the elastic scattering off the polarised electrons of a ferromagnetic target whose magnetisation is periodically reversed. At muon energies of 100 and 190 GeV the measured polarisation is P{sub {mu}}=-0.80{+-}0.03 (stat.){+-}0.02 (syst.) and P{sub {mu}}=-0.797{+-}0.011 (stat.){+-}0.012 (syst.), respectively. These results agree with measurements of the beam polarisation using a shape analysis of the decay positron energy spectrum.
DEFF Research Database (Denmark)
Myrdal, Jon Steinar Gardarsson; Blanchard, Didier; Sveinbjörnsson, Dadi Þorsteinn
2013-01-01
to quasi-elastic neutron scattering (QENS) measurements with and without an applied bias potential of 3 V. DFT calculations show that lithium defects such as Frenkel pairs are easily formed at room temperature (formation energy of 0.44 eV) and low energy barriers (0.2 to 0.3 eV) are found between stable...
Cross-sections and spin observables in proton-proton elastic scattering: Results from EDDA at COSY
Energy Technology Data Exchange (ETDEWEB)
Rohdjess, H.; Bisplinghoff, J.; Busch, M.; Dahl, C.; Eversheim, P.D.; Hinterberger, F.; Meinerzhagen, A. [Helmholtz-Institut fuer Strahlen- und Kernphysik, Universitaet Bonn, D-53115, Bonn (Germany); Bauer, F.; Buesser, K.; Colberg, T.; Demiroers, L.; Eyser, O.; Greiff, J.; Jonas, E.; Krause, H.; Lehmann, C.; Lindlein, J. [Institut fuer Experimentalphysik, Universitaet Hamburg, D-22761, Hamburg (Germany); Felden, O.; Gebel, R.; Maier, R. [Institut fuer Kernphysik, Forschungszentrum Juelich, D-52425, Juelich (Germany); Pauly, C.; Prasuhn, D.; Rosendaal, D.; Rossen, P. von; Schirm, N.; Scobel, W.; Ulbrich, K.; Weise, E.; Wolf, T.; Ziegler, R.
2003-11-01
At the Cooler-Synchrotron COSY/Juelich polarized and unpolarized elastic proton-proton scattering has been investigated with the EDDA-Experiment in the energy range (T{sub p} {approx}0.5-2.5 GeV). By taking scattering data during the acceleration of the beam with a large-acceptance ({theta}{sub c.m.} {approx}30 -90 ) detector, precise excitation functions for differential cross-section and analyzing power have been measured in small energy steps with consistent normalization with respect to luminosity and polarization. These data have helped to improve the determination of phase-shifts at higher energies and impose tight quantitative upper bounds on possible resonant contributions to pp elastic scattering, as they might arise from exotic 6-quark configurations. Recently, with polarized beam and target, the spin-correlation parameters A{sub NN}, A{sub SS}, and A{sub SL} have been determined at 10 energies between 0.8 and 2.5 GeV. The observable A{sub SS} has been measured the first time above 800 MeV and our results are in sharp contrast to phase-shift predictions at higher energies. (orig.)
Bussey, Peter; The ATLAS collaboration
2017-01-01
A summary is given of recent ATLAS results at the LHC, covering a number of areas that reflect the Collaboration’s work in low energy physical observables in multiparticle events, elastic photon-photon scattering, proton-proton scattering.and the tagging of diffractive events.
Nonlinear coda wave analysis of hysteretic elastic behavior in strongly scattering media
Ouarabi, M. Ait; Boubenider, F.; Gliozzi, A. S.; Scalerandi, M.
2016-10-01
Strongly scattering elastic media, such as consolidated granular materials, respond to ultrasonic pulse excitations with a long response signal with peculiar properties. The portion of the signal at late times, termed coda, is due to multiple scattering. It contains information about the elastic properties of the material, and it has been proven to be very sensitive to small variations in the modulus. Here we propose a technique based on a nonlinear analysis of the coda of a signal, which might be applied to quantify the nonlinear elastic response in consolidated granular media exhibiting a hysteretic elastic behavior. The method proposed allows for an intrinsic definition of the reference signal which is normally needed for applying coda-based methods.
Energy Technology Data Exchange (ETDEWEB)
Wang, A.Z.F.
1977-11-01
The physical and chemical properties of metastable rare gas atoms are discussed and summarized. This is followed by a detailed examination of the various possible pathways whereby the metastable's excess electronic energy can be dissipated. The phenomenon of chemi-ionization is given special emphasis, and a theoretical treatment based on the use of complex (optical) potential is presented. This is followed by a discussion on the unique advantages offered by elastic differential cross section measurements in the apprehension of the fundamental forces governing the ionization process. The methodology generally adopted to extract information about the interaction potential for scattering data is also systematically outlined. Two widely studied chemi-ionization systems are then closely examined in the light of accurate differential cross section measurements obtained in this work. The first system is He(2/sup 3/S) + Ar for which one can obtain an interaction potential which is in good harmony with the experimental results of other investigators. The validity of using the first-order semiclassical approximation for the phase shifts calculation in the presence of significant opacities is also discussed. The second reaction studied is He*+D/sub 2/ for which measurements were made on both spin states of the metastable helium. A self-consistent interaction potential is obtained for the triplet system, and reasons are given for not being able to do likewise for the singlet system. The anomalous hump proposed by a number of laboratories is analyzed. Total elastic and ionization cross sections as well as rate constants are calculated for the triplet case. Good agreement with experimental data is found. Finally, the construction and operation of a high power repetitively pulsed nitrogen laser pumped dye laser system is described in great details. Details for the construction and operation of a flashlamp pumped dye laser are likewise given.
Net Balanced Floorplanning Based on Elastic Energy Model
DEFF Research Database (Denmark)
Liu, Wei; Nannarelli, Alberto
2008-01-01
with balanced net delays to increase the safety margins of the design. In this paper, we investigate the properties of floorplanning based on the elastic energy model. The B*-tree, which is based on an ordered binary tree, is used for circuit representation and the elastic energy is used as the cost function...
Energy Technology Data Exchange (ETDEWEB)
Bigio, I.J.; Boyer, J.; Johnson, T.M.; Lacey, J.; Mourant, J.R. [Los Alamos National Lab., NM (United States); Conn, R. [Lovelace Medical Center, Albuquerque, NM (United States); Bohorfoush, A. [Wisconsin Medical School, Milwaukee, WI (United States)
1994-10-01
The Los Alamos National Laboratory has continued the development of the Optical Biopsy System (OBS) for noninvasive, real-time in situ diagnosis of tissue pathologies. Our clinical studies have expanded since the last Biomedical Optics Europe conference (Budapest, September 1993), and we report here on the latest results of clinical tests in gastrointestinal tract. The OBS invokes a unique approach to optical diagnosis of tissue pathologies based on the elastic scattering properties, over a wide range of wavelengths, of the tissue. The use of elastic scattering as the key to optical tissue diagnostics in the OBS is based on the fact that many tissue pathologies, including a majority of cancer forms, manifest significant architectural changes at the cellular and sub-cellular level. Since the cellular components that cause elastic scattering have dimensions typically on the order of visible to near-IR wavelengths, the elastic (Mie) scattering properties will be wavelength dependent. Thus, morphology and size changes can be expected to cause significant changes in an optical signature that is derived from the wavelength-dependence of elastic scattering. The OBS employs a small fiberoptic probe that is amenable to use with any endoscope or catheter, or to direct surface examination. The probe is designed to be used in optical contact with the tissue under examination and has separate illuminating and collecting fibers. Thus, the light that is collected and transmitted to the analyzing spectrometer must first scatter through a small volume of the tissue before entering the collection fiber(s). Consequently, the system is also sensitive to the optical absorption spectrum of the tissue, over an effective operating range of <300 to 950 nm, and such absorption adds valuable complexity to the scattering spectral signature.
A study of quasi-elastic muon neutrino and antineutrino scattering in the NOMAD experiment
Lyubushkin, V.; Popov, B.; Kim, J. J.; Camilleri, L.; Levy, J.-M.; Mezzetto, M.; Naumov, D.; Alekhin, S.; Astier, P.; Autiero, D.; Baldisseri, A.; Baldo-Ceolin, M.; Banner, M.; Bassompierre, G.; Benslama, K.; Besson, N.; Bird, I.; Blumenfeld, B.; Bobisut, F.; Bouchez, J.; Boyd, S.; Bueno, A.; Bunyatov, S.; Cardini, A.; Cattaneo, P. W.; Cavasinni, V.; Cervera-Villanueva, A.; Challis, R.; Chukanov, A.; Collazuol, G.; Conforto, G.; Conta, C.; Contalbrigo, M.; Cousins, R.; Daniels, D.; Degaudenzi, H.; Del Prete, T.; de Santo, A.; Dignan, T.; di Lella, L.; Do Couto E Silva, E.; Dumarchez, J.; Ellis, M.; Feldman, G. J.; Ferrari, R.; Ferrère, D.; Flaminio, V.; Fraternali, M.; Gaillard, J.-M.; Gangler, E.; Geiser, A.; Geppert, D.; Gibin, D.; Gninenko, S.; Godley, A.; Gomez-Cadenas, J.-J.; Gosset, J.; Gößling, C.; Gouanère, M.; Grant, A.; Graziani, G.; Guglielmi, A.; Hagner, C.; Hernando, J.; Hubbard, D.; Hurst, P.; Hyett, N.; Iacopini, E.; Joseph, C.; Juget, F.; Kent, N.; Kirsanov, M.; Klimov, O.; Kokkonen, J.; Kovzelev, A.; Krasnoperov, A.; Kulagin, S.; Kustov, D.; Lacaprara, S.; Lachaud, C.; Lakić, B.; Lanza, A.; La Rotonda, L.; Laveder, M.; Letessier-Selvon, A.; Ling, J.; Linssen, L.; Ljubičić, A.; Long, J.; Lupi, A.; Marchionni, A.; Martelli, F.; Méchain, X.; Mendiburu, J.-P.; Meyer, J.-P.; Mishra, S. R.; Moorhead, G. F.; Nédélec, P.; Nefedov, Yu.; Nguyen-Mau, C.; Orestano, D.; Pastore, F.; Peak, L. S.; Pennacchio, E.; Pessard, H.; Petti, R.; Placci, A.; Polesello, G.; Pollmann, D.; Polyarush, A.; Poulsen, C.; Rebuffi, L.; Rico, J.; Riemann, P.; Roda, C.; Rubbia, A.; Salvatore, F.; Samoylov, O.; Schahmaneche, K.; Schmidt, B.; Schmidt, T.; Sconza, A.; Seaton, M.; Sevior, M.; Sillou, D.; Soler, F. J. P.; Sozzi, G.; Steele, D.; Stiegler, U.; Stipčević, M.; Stolarczyk, Th.; Tareb-Reyes, M.; Taylor, G. N.; Tereshchenko, V.; Toropin, A.; Touchard, A.-M.; Tovey, S. N.; Tran, M.-T.; Tsesmelis, E.; Ulrichs, J.; Vacavant, L.; Valdata-Nappi, M.; Valuev, V.; Vannucci, F.; Varvell, K. E.; Veltri, M.; Vercesi, V.; Vidal-Sitjes, G.; Vieira, J.-M.; Vinogradova, T.; Weber, F. V.; Weisse, T.; Wilson, F. F.; Winton, L. J.; Wu, Q.; Yabsley, B. D.; Zaccone, H.; Zuber, K.; Zuccon, P.
2009-10-01
We have studied the muon neutrino and antineutrino quasi-elastic (QEL) scattering reactions ( ν μ n→ μ - p and bar{ν }_{μ}ptoμ+n ) using a set of experimental data collected by the NOMAD Collaboration. We have performed measurements of the cross-section of these processes on a nuclear target (mainly carbon) normalizing it to the total ν μ ( bar{ν}_{μ} ) charged-current cross section. The results for the flux-averaged QEL cross sections in the (anti)neutrino energy interval 3-100 GeV are < σ_{qel}rangle_{ν_{μ}}=(0.92±0.02(stat)±0.06(syst))×10^{-38} cm2 and <σ_{qel}rangle_{bar{ν}_{μ}}=(0.81±0.05(stat)±0.09(syst))×10^{-38} cm2 for neutrino and antineutrino, respectively. The axial mass parameter M A was extracted from the measured quasi-elastic neutrino cross section. The corresponding result is M A =1.05±0.02(stat)±0.06(syst) GeV. It is consistent with the axial mass values recalculated from the antineutrino cross section and extracted from the pure Q 2 shape analysis of the high purity sample of ν μ quasi-elastic 2-track events, but has smaller systematic error and should be quoted as the main result of this work. Our measured M A is found to be in good agreement with the world average value obtained in previous deuterium filled bubble chamber experiments. The NOMAD measurement of M A is lower than those recently published by K2K and MiniBooNE Collaborations. However, within the large errors quoted by these experiments on M A , these results are compatible with the more precise NOMAD value.
Energy transfer in scattering by rotating potentials
Indian Academy of Sciences (India)
Quantum mechanical scattering theory is studied for time-dependent Schrödinger operators, in particular for particles in a rotating potential. Under various assumptions about the decay rate at infinity we show uniform boundedness in time for the kinetic energy of scattering states, existence and completeness of wave ...
Low-energy positron scattering upon endohedrals
Amusia, M. Ya.; Chernysheva, L. V.
2017-07-01
We investigate positron scattering upon endohedrals and compare it with electron-endohedral scattering. We show that the polarization of the fullerene shell considerably alters the polarization potential of an atom, stuffed inside a fullerene. This essentially affects both the positron and electron elastic scattering phases as well as corresponding cross sections. Of great importance is also the interaction between the incoming positron and the target electrons that leads to formation of the virtual positronium P˜s. We illustrate the general trend by concrete examples of positron and electron scattering upon endohedrals He@C60 and Ar@C60, and compare it to scattering upon fullerene C60. To obtain the presented results, we have employed new simplified approaches that permit to incorporate the effect of fullerenes polarizability into the He@C60 and Ar@C60 polarization potential and to take into account the virtual positronium formation. Using these approaches, we obtained numeric results that show strong variations in shape and magnitudes of scattering phases and cross sections due to effect of endohedral polarization and P˜s formation.
von Schmid, M.; Bagchi, S.; Bonig, S.; Csatlos, M.; Dillmann, I.; Dimopoulou, C.; Egelhof, P.; Eremin, V.; Furuno, T.; Geissel, H.; Gernhaeuser, R.; Harakeh, M. N.; Hartig, A-L; Ilieva, S.; Kalantar-Nayestanaki, N.; Kiselev, O.; Kollmus, H.; Kozhuharov, C.; Krasznahorkay, A.; Kroell, T.; Kuilman, M.; Litvinov, S.; Litvinov, Yu A.; Mahjour-Shafiei, M.; Mutterer, M.; Nagae, D.; Najafi, M. A.; Nociforo, C.; Nolden, F.; Popp, U.; Rigollet, C.; Roy, S.; Scheidenberger, C.; Steck, M.; Streicher, B.; Stuhl, L.; Thuerauf, M.; Uesaka, T.; Weick, H.; Winfield, J. S.; Winters, D.; Woods, P. J.; Yamaguchi, T.; Yue, K.; Zamora, J. C.; Zenihiro, J.
2015-01-01
We have measured the nuclear-matter distribution of the doubly-magic N = Z nucleus Ni-56 by investigating elastic proton scattering in inverse kinematics. The radioactive beam of Ni-56 was injected and stored in the experimental storage ring (ESR, GSI) and interacted with an internal hydrogen
Energy Technology Data Exchange (ETDEWEB)
Andrei V. Afanasev; Stanley J. Brodsky; Carl E. Carlson; Yu-Chun Chen; Marc Vanderhaeghen
2005-01-01
We estimate the two-photon exchange contribution to elastic electron-proton scattering at large momentum transfer by using a quark-parton representation of virtual Compton scattering. We thus can relate the two-photon exchange amplitude to the generalized parton distributions which also enter in other wide angle scattering processes. We find that the interference of one- and two-photon exchange contribution is able to substantially resolve the difference between electric form factor measurements from Rosenbluth and polarization transfer experiments.
The prediction of Neutron Elastic Scattering from Tritium for E(n) = 6-14 MeV
Energy Technology Data Exchange (ETDEWEB)
Anderson, J D; Dietrich, F S; Luu, T; McNabb, D P; Navratil, P; Quaglioni, S
2010-06-14
In a recent report Navratil et al. evaluated the angle-integrated cross section and the angular distribution for 14-MeV n+T elastic scattering by inferring these cross sections from accurately measured p+3He angular distributions. This evaluation used a combination of two theoretical treatments, based on the no-core shell model and resonating-group method (NCSM/RGM) and on the R-matrix formalism, to connect the two charge-symmetric reactions n+T and p+{sup 3}He. In this report we extend this treatment to cover the neutron incident energy range 6-14 MeV. To do this, we evaluate angle-dependent correction factors for the NCSM/RGM calculations so that they agree with the p+{sup 3}He data near 6 MeV, and using the results found earlier near 14 MeV we interpolate these correction factors to obtain correction factors throughout the 6-14 MeV energy range. The agreement between the corrected NCSM/RGM and R-Matrix values for the integral elastic cross sections is excellent ({+-}1%), and these are in very good agreement with total cross section experiments. This result can be attributed to the nearly constant correction factors at forward angles, and to the evidently satisfactory physics content of the two calculations. The difference in angular shape, obtained by comparing values of the scattering probability distribution P({mu}) vs. {mu}(the cosine of the c.m. scattering angle), is about {+-}4% and appears to be related to differences in the two theoretical calculations. Averaging the calculations yields P({mu}) values with errors of {+-}2 1/2 % or less. These averaged values, along with the corresponding quantities for the differential cross sections, will form the basis of a new evaluation of n+T elastic scattering. Computer files of the results discussed in this report will be supplied upon request.
Silva, H.; Cruz, J.; Sánchez-Benítez, A. M.; Santos, C.; Luís, H.; Fonseca, M.; Jesus, A. P.
2017-09-01
In recent decades, the processes of fusion of 16O were studied both theoretically and experimentally. However, the theoretical calculations are unable to fit both elastic scattering cross sections and fusion S-factors. The use of 16O thin transmission targets is required to measure the elastic forward scattering 16O + 16O reaction. The areal density of the target must be high to maximize the reaction products yields, but not so high as to allow a correct calculation of the effective beam energy. Besides this, the target must withstand beam interactions without noticeable deterioration, and contaminants must be minimal. In this study, the production of thin targets is performed with an innovative technique. Beam characterization and preliminary spectrum for the elastic scattering are also presented, showing the suitability of these targets for the proposed reaction.
Elastic energy release in great earthquakes and eruptions
Directory of Open Access Journals (Sweden)
Agust eGudmundsson
2014-05-01
Full Text Available The sizes of earthquakes are measured using well-defined, measurable quantities such as seismic moment and released (transformed elastic energy. No similar measures exist for the sizes of volcanic eruptions, making it difficult to compare the energies released in earthquakes and eruptions. Here I provide a new measure of the elastic energy (the potential mechanical energy associated with magma chamber rupture and contraction (shrinkage during an eruption. For earthquakes and eruptions, elastic energy derives from two sources: (1 the strain energy stored in the volcano/fault zone before rupture, and (2 the external applied load (force, pressure, stress, displacement on the volcano/fault zone. From thermodynamic considerations it follows that the elastic energy released or transformed (dU during an eruption is directly proportional to the excess pressure (pe in the magma chamber at the time of rupture multiplied by the volume decrease (-dVc of the chamber, so that . This formula can be used as a basis for a new eruption magnitude scale, based on elastic energy released, which can be related to the moment-magnitude scale for earthquakes. For very large eruptions (>100 km3, the volume of the feeder-dike is negligible, so that the decrease in chamber volume during an eruption corresponds roughly to the associated volume of erupted materials , so that the elastic energy is . Using a typical excess pressures of 5 MPa, it is shown that the largest known eruptions on Earth, such as the explosive La Garita Caldera eruption (27-28 million years ago and largest single (effusive Colombia River basalt lava flows (15-16 million years ago, both of which have estimated volumes of about 5000 km3, released elastic energy of the order of 10EJ. For comparison, the seismic moment of the largest earthquake ever recorded, the M9.5 1960 Chile earthquake, is estimated at 100 ZJ and the associated elastic energy release at 10EJ.
Energy Technology Data Exchange (ETDEWEB)
Bigio, I.J.; Loree, T.R.; Mourant, J.; Shimada, T. [Los Alamos National Lab., NM (United States); Story-Held, K.; Glickman, R.D. [Texas Univ. Health Science Center, San Antonio, TX (United States). Dept. of Ophthalmology; Conn, R. [Lovelace Medical Center, Albuquerque, NM (United States). Dept. of Urology
1993-08-01
A non-invasive diagnostic tool that could identify malignancy in situ and in real time would have a major impact on the detection and treatment of cancer. We have developed and are testing early prototypes of an optical biopsy system (OBS) for detection of cancer and other tissue pathologies. The OBS invokes a unique approach to optical diagnosis of tissue pathologies based on the elastic scattering properties, over a wide range of wavelengths, of the microscopic structure of the tissue. The use of elastic scattering as the key to optical tissue diagnostics in the OBS is based on the fact that many tissue pathologies, including a majority of cancer forms, manifest significant architectural changes at the cellular and sub-cellular level. Since the cellular components that cause elastic scattering have dimensions typically on the order of visible to near-IR wavelengths, the elastic (Mie) scattering properties will be strongly wavelength dependent. Thus, morphology and size changes can be expected to cause significant changes in an optical signature that is derived from the wavelength dependence of elastic scattering. The data acquisition and storage/display time with the OBS instrument is {approximately}1 second. Thus, in addition to the reduced invasiveness of this technique compared with current state-of-the-art methods (surgical biopsy and pathology analysis), the OBS offers the possibility of impressively faster diagnostic assessment. The OBS employs a small fiber-optic probe that is amenable to use with any endoscope, catheter or hypodermic, or to direct surface examination (e.g. as in skin cancer or cervical cancer). It has been tested in vitro on animal and human tissue samples, and clinical testing in vivo is currently in progress.
Molecular basis for elastic energy storage in mineralized tendon.
Silver, F H; Freeman, J W; Horvath, I; Landis, W J
2001-01-01
Animals store elastic energy in leg and foot tendons during locomotion. In the turkey, much of the locomotive force generated by the gastrocnemius muscle is stored as elastic energy during tendon deformation. Little energy storage occurs within the muscle. During growth of some avians, including the turkey, leg tendons mineralize in the portions distal to the attached muscle and show increased tensile strength and modulus as a result. The purpose of this study is to test the hypothesis that the degree of elastic energy storage in mineralizing turkey tendon is directly related to the tendon mineral content. To test this hypothesis, the stress-strain behavior of tendons was separated into elastic and viscous components. Both the elastic spring constant and the elastic energy stored, calculated up to a strain of 20%, were found to be proportional to tendon mineral content. It is concluded that mineralization is an efficient means for increasing the amount of elastic energy storage that is required for increased load-bearing ability needed for locomotion of adult birds. Examination of molecular models of the hole region, where mineralization is initiated within the collagen fibril, leads to the hypothesis that elastic energy is stored in the tendon by direct stretching of the flexible regions. Flexible regions within the collagen molecule fall within the positively stained bands of the collagen D period. It is proposed that mineralization increases the stored elastic energy by preventing flexible regions within the positively stained bands from stretching. These observations suggest that mineralization begins in the hole region due to the large number of charged amino acid residues found in the d and e bands.
Elastic and Inelastic Scattering of 8He Using a Solid Hydrogen Target
Holl, Matthias; Kanungo, Ritu; Alcorta, Martin; Connolly, Devin; Davids, Barry; Diaz Varela, Alejandra; Hackman, Greg; Henderson, Jack; Ishimoto, Shigeru; Ihsan Kilic, Ali; Krücken, Reiner; Lennarz, Annika; Liang, Johnson; Measures, James; Mittig, Wolfgang; Paetkau, Owen; Psaltus, Athanasios; Singh Randhawa, Jaspreet; Smallcombe, James; Williams, Matt
2017-09-01
The nucleus 8He is the most neutron-rich nucleus known. Its structure, consisting of a 4He core surrounded by four neutrons makes it an ideal case to study phenomena in highly neutron-proton asymmetric systems. An experiment studying elastic and inelastic scattering of 8He has been carried out at the IRIS setup at ISAC-II at TRIUMF. It utilized the novel IRIS solid H2 target in combination with a low pressure ionization chamber for the identification of the incoming beam and two ΔE - E telescopes to measure the reaction products. The current status of the analysis will be shown, including the optical model analysis of the elastic scattering compared to global potentials and the analysis of excited states in 8He from inelastic scattering. Support Limit from Canada Foundation for Innovation, Nova Scotia Research and Innovation Trust and NSERC.
A Hamiltonian theory for an elastic earth. II - Elastic energy of deformation
Getino, Juan; Ferrandiz, Jose M.
1991-03-01
The perturbation due to the deformation of the elastic mantle by a tidal body force and due to the centrifugal potential are studied. Two previously defined canonical systems of variables (elastic variables of Euler and Andoyer) are used for building the elastic energy produced by the deformation of the elastic mantle. The general expression of earth's elastic deformation energy of the second order is derived; this expression is independent of the earth model being used. The expression is applied to a particular earth model, and it is found out that the kinetic energy to the order of zero, T0 is 10 exp -13 for the deformation produced by the moon, and 10 exp -14 for that produced by the sun. An approximate analytical integration of the Hamiltonian of rotational motion is obtained, including terms for the deformation-induced perturbation of the kinetic and elastic energy as well as the tidal and centrifugal potentials. Numerical results are presented in tables, and Chandler's period is estimated as 457 days, slightly lower than recent experimental determinations.
Quasi-elastic neutron scattering study of dynamics in condensed ...
Indian Academy of Sciences (India)
with respect to energy by a large analyser crystal (in MARX mode) and detected by a position sensitive detector. Details of this spectrometer are given in [3]. The instrumental resolution is obtained from the measured FWHM of the spectrum of a vanadium sample. In the present configuration, the instrument has an energy.
Double folding model analysis of elastic scattering of halo nucleus ...
Indian Academy of Sciences (India)
2014-04-17
Coulomb barrier energy have been performed using a potential obtained from the double folding model and are compared with the experiment. In the framework of the double folding model, the nuclear matter densities of 9,10 ...
Anghinolfi, F.; S. Ask; Barrillon, P.; Blanchot, G; Blin, S.; Braem, André; C. De La Taille; Di Girolamo, B.; I. Efthymiopoulos(CERN, Geneva, Switzerland); Faustino, J; Fournier, D.; Franz, S.; Grafström, P.; Gurriana, L.; Haguenauer, M.
2007-01-01
A scintillating fibre tracker is proposed to measure elastic proton scattering at very small angles in the ATLAS experiment at CERN. The tracker will be located in so-called Roman Pot units at a distance of 240 m on each side of the ATLAS interaction point. An initial validation of the design choices was achieved in a beam test at DESY in a relatively low energy electron beam and using slow off-the-shelf electronics. Here we report on the results from a second beam test experiment carried out...
Zero energy scattering calculation in Euclidean space
Energy Technology Data Exchange (ETDEWEB)
Carbonell, J. [Institut de Physique Nucléaire, Université Paris-Sud, IN2P3-CNRS, 91406 Orsay Cedex (France); Karmanov, V.A., E-mail: karmanov@sci.lebedev.ru [Lebedev Physical Institute, Leninsky Prospekt 53, 119991 Moscow (Russian Federation)
2016-03-10
We show that the Bethe–Salpeter equation for the scattering amplitude in the limit of zero incident energy can be transformed into a purely Euclidean form, as it is the case for the bound states. The decoupling between Euclidean and Minkowski amplitudes is only possible for zero energy scattering observables and allows determining the scattering length from the Euclidean Bethe–Salpeter amplitude. Such a possibility strongly simplifies the numerical solution of the Bethe–Salpeter equation and suggests an alternative way to compute the scattering length in Lattice Euclidean calculations without using the Luscher formalism. The derivations contained in this work were performed for scalar particles and one-boson exchange kernel. They can be generalized to the fermion case and more involved interactions.
Simulation of low-energy ion scattering
Langelaar, M. H.; Breeman, M.; Mijiritskii, A. V.; Boerma, D. O.
A new simulation program `MATCH' has been developed for a detailed analysis of low-energy ion scattering (LEIS) and recoiling data. Instead of performing the full calculation of the three-dimensional trajectories through the sample from the ion source towards the detector, incoming trajectories as well as reversed-time outgoing trajectories are calculated, separately. Finally, these trajectories are matched to obtain the yield. The program has been tested for spectra and azimuthal scans of scattering and recoiling events of various sample species in different scattering geometries.
Elastic scattering and total reaction cross section for the {sup 6}He+{sup 58}Ni system
Energy Technology Data Exchange (ETDEWEB)
Morcelle, V. [Instituto de Física - Universidade Federal Fluminense, 24210-346, Rio de Janeiro, Brazil and Universidade Federal de Itajubá, 35900-030, Itabira (Brazil); Lichtenthäler, R.; Lépine-Szily, A.; Guimarães, V.; Gasques, L.; Scarduelli, V.; Condori, R. Pampa; Leistenschneider, E. [Depto de Física Nuclear, Universidade de São Paulo, C.P. 66318, 05389-970, São Paulo (Brazil); Mendes Jr, D. R.; Faria, P. N. de [Instituto de Física - Universidade Federal Fluminense, 24210-346, Rio de Janeiro (Brazil); Pires, K. C. C. [Universidade Tecnológica Federal do Paraná, 86300-000, Cornélio Procópio (Brazil); Barioni, A. [Instituto de Física, Universidade Federal da Bahia, 40210-340, Bahia (Brazil); Morais, M. C. [Centro Brasileiro de Pesquisas Físicas, 22290-180, Rio de Janeiro (Brazil); Shorto, J. M. B. [Instituto de Pesquisas Energéticas e Nucleares- IPEN, 05508-000, São Paulo (Brazil); Zamora, J. C. [Departament of Physics, Technische Universität Darmstadt (Germany)
2014-11-11
Elastic scattering measurements of {sup 6}He + {sup 58}Ni system have been performed at the laboratory energy of 21.7 MeV. The {sup 6}He secondary beam was produced by a transfer reaction {sup 9}Be ({sup 7}Li, {sup 6}He) and impinged on {sup 58}Ni and {sup 197}Au targets, using the Radioactive Ion Beam (RIB) facility, RIBRAS, installed in the Pelletron Laboratory of the Institute of Physics of the University of São Paulo, Brazil. The elastic angular distribution was obtained in the angular range from 15° to 80° in the center of mass frame. Optical model calculations have been performed using a hybrid potential to fit the experimental data. The total reaction cross section was derived.
Ps-atom scattering at low energies
Fabrikant, I I
2015-01-01
A pseudopotential for positronium-atom interaction, based on electron-atom and positron-atom phase shifts, is constructed, and the phase shifts for Ps-Kr and Ps-Ar scattering are calculated. This approach allows us to extend the Ps-atom cross sections, obtained previously in the impulse approximation [Phys. Rev. Lett. 112, 243201 (2014)], to energies below the Ps ionization threshold. Although experimental data are not available in this low-energy region, our results describe well the tendency of the measured cross sections to drop with decreasing velocity at $v<1$ a.u. Our results show that the effect of the Ps-atom van der Waals interaction is weak compared to the polarization interaction in electron-atom and positron-atom scattering. As a result, the Ps scattering length for both Ar and Kr is positive, and the Ramsauer-Townsend minimum is not observed for Ps scattering from these targets. This makes Ps scattering quite different from electron scattering in the low-energy region, in contrast to the inter...
Forward two-photon exchange in elastic lepton-proton scattering and hyperfine-splitting correction
Energy Technology Data Exchange (ETDEWEB)
Tomalak, Oleksandr [Johannes Gutenberg Universitaet, Institut fuer Kernphysik and PRISMA Cluster of Excellence, Mainz (Germany)
2017-08-15
We relate the forward two-photon exchange (TPE) amplitudes to integrals of the inclusive lepton-proton scattering cross sections. These relations yield an alternative way for the evaluation of the TPE correction to hyperfine-splitting (HFS) in the hydrogen-like atoms with an equivalent to the standard approach (Iddings, Drell and Sullivan) result implying the Burkhardt-Cottingham sum rule. For evaluation of the individual effects (e.g., elastic contribution) our approach yields a distinct result. We compare both methods numerically on examples of the elastic contribution and the full TPE correction to HFS in electronic and muonic hydrogen. (orig.)
Anti-Neutrino Charged Current Quasi-Elastic Scattering in MINER$\
Energy Technology Data Exchange (ETDEWEB)
Chvojka, Jesse John [Univ. of Rochester, NY (United States)
2012-01-01
The phenomenon of neutrino oscillation is becoming increasingly understood with results from accelerator-based and reactor-based experiments, but unanswered questions remain. The proper ordering of the neutrino mass eigenstates that compose the neutrino avor eigenstates is not completely known. We have yet to detect CP violation in neutrino mixing, which if present could help explain the asymmetry between matter and anti-matter in the universe. We also have not resolved whether sterile neutrinos, which do not interact in any Standard Model interaction, exist. Accelerator-based experiments appear to be the most promising candidates for resolving these questions; however, the ability of present and future experiments to provide answers is likely to be limited by systematic errors. A significant source of this systematic error comes from limitations in our knowledge of neutrino-nucleus interactions. Errors on cross-sections for such interactions are large, existing data is sometimes contradictory, and knowledge of nuclear effects is incomplete. One type of neutrino interaction of particular interest is charged current quasi-elastic (CCQE) scattering, which yields a final state consisting of a charged lepton and nucleon. This process, which is the dominant interaction near energies of 1 GeV, is of great utility to neutrino oscillation experiments since the incoming neutrino energy and the square of the momentum transferred to the final state nucleon, Q^{2}, can be reconstructed using the final state lepton kinematics. To address the uncertainty in our knowledge of neutrino interactions, many experiments have begun making dedicated measurements. In particular, the MINER A experiment is studying neutrino-nucleus interactions in the few GeV region. MINERvA is a fine-grained, high precision, high statistics neutrino scattering experiment that will greatly improve our understanding of neutrino cross-sections and nuclear effects that affect the final state particles
A study of quasi-elastic muon neutrino and antineutrino scattering in the NOMAD experiment
Energy Technology Data Exchange (ETDEWEB)
Lyubushkin, V.; Bunyatov, S.; Chukanov, A.; Klimov, O.; Kustov, D.; Nefedov, Yu.; Samoylov, O.; Tereshchenko, V. [JINR, Dubna (Russian Federation); Popov, B. [JINR, Dubna (Russian Federation); LPNHE, Univ. of Paris VI and VII, Paris (France); Kim, J.J.; Godley, A.; Ling, J.; Mishra, S.R.; Petti, R.; Seaton, M.; Wu, Q. [Univ. of South Carolina, Columbia, SC (United States); Camilleri, L.; Autiero, D.; Di Lella, L.; Couto e Silva, E. do; Ferrere, D.; Grant, A.; Kokkonen, J.; Linssen, L.; Placci, A.; Stiegler, U.; Tsesmelis, E.; Vidal-Sitjes, G.; Wilson, F.F. [CERN, Geneva (Switzerland); Levy, J.M.; Astier, P.; Banner, M.; Dumarchez, J.; Lachaud, C.; Letessier-Selvon, A.; Schahmaneche, K.; Touchard, A.M.; Vannucci, F. [LPNHE, Univ. of Paris VI and VII, Paris (France); Mezzetto, M.; Baldo-Ceolin, M.; Bobisut, F.; Collazuol, G.; Contalbrigo, M.; Gibin, D.; Guglielmi, A.; Lacaprara, S.; Laveder, M.; Rebuffi, L.; Sconza, A.; Zuccon, P. [Univ. of Padova (Italy); INFN, Padova (Italy); Naumov, D. [JINR, Dubna (Russian Federation); Univ. of Florence (Italy); INFN, Florence (Italy); Alekhin, S. [Inst. for High Energy Physics, Protvino, Moscow Region (Russian Federation); Baldisseri, A.; Besson, N.; Bouchez, J.; Gosset, J.; Hagner, C.; Mechain, X.; Meyer, J.P.; Stolarczyk, T.; Zaccone, H. [DAPNIA, Saclay (France); Bassompierre, G.; Gaillard, J.M.; Gouanere, M.; Mendiburu, J.P.; Nedelec, P.; Pessard, H.; Sillou, D. [LAPP, Annecy (France); Benslama, K.; Degaudenzi, H.; Joseph, C.; Juget, F.; Nguyen-Mau, C.; Sozzi, G.; Tareb-Reyes, M.; Tran, M.T.; Vacavant, L.; Vieira, J.M. [Univ. of Lausanne, Lausanne (Switzerland); Bird, I. [CERN, Geneva (Switzerland); Univ. of Lausanne (Switzerland); Blumenfeld, B.; Long, J. [Johns Hopkins Univ., Baltimore, MD (United States); Boyd, S.; Ellis, M.; Peak, L.S.; Ulrichs, J.; Varvell, K.E.; Yabsley, B.D. [Univ. of Sydney (Australia); Bueno, A. [Harvard Univ., Cambridge, MA (United States); ETH Zurich (Switzerland)] [and others
2009-10-15
We have studied the muon neutrino and antineutrino quasi-elastic (QEL) scattering reactions ({nu}{sub {mu}}n {yields}{mu}{sup -}p and anti {nu}{sub {mu}}p{yields}{mu}{sup +}n) using a set of experimental data collected by the NOMAD Collaboration. We have performed measurements of the cross-section of these processes on a nuclear target (mainly carbon) normalizing it to the total {nu}{sub {mu}}(anti {nu}{sub {mu}}) charged-current cross section. The results for the flux-averaged QEL cross sections in the (anti)neutrino energy interval 3-100 GeV are left angle {sigma}{sub qel} right angle {sub {nu}}{sub {mu}}=(0.92{+-}0.02(stat){+-}0.06(syst)) x 10{sup -38} cm{sup 2} and left angle {sigma}{sub qel} right angle {sub anti} {sub {nu}{sub {mu}}}{sub =}(0.81{+-}0.05(stat){+-}0.09(syst)) x 10{sup -38} cm{sup 2} for neutrino and antineutrino, respectively. The axial mass parameter M{sub A} was extracted from the measured quasi-elastic neutrino cross section. The corresponding result is M{sub A}=1.05{+-}0.02(stat){+-}0.06(syst) GeV. It is consistent with the axial mass values recalculated from the antineutrino cross section and extracted from the pure Q{sup 2} shape analysis of the high purity sample of {nu}{sub {mu}} quasi-elastic 2-track events, but has smaller systematic error and should be quoted as the main result of this work. Our measured M{sub A} is found to be in good agreement with the world average value obtained in previous deuterium filled bubble chamber experiments. The NOMAD measurement of M{sub A} is lower than those recently published by K2K and MiniBooNE Collaborations. However, within the large errors quoted by these experiments on M{sub A}, these results are compatible with the more precise NOMAD value. (orig.)
Isomer beam elastic scattering: 26mAl(p, p) for astrophysics
Kahl, D.; Shimizu, H.; Yamaguchi, H.; Abe, K.; Beliuskina, O.; Cha, S. M.; Chae, K. Y.; Chen, A. A.; Ge, Z.; Hayakawa, S.; Imai, N.; Iwasa, N.; Kim, A.; Kim, D. H.; Kim, M. J.; Kubono, S.; Kwag, M. S.; Liang, J.; Moon, J. Y.; Nishimura, S.; Oka, S.; Park, S. Y.; Psaltis, A.; Teranishi, T.; Ueno, Y.; Yang, L.
2018-01-01
The advent of radioactive ground-state beams some three decades ago ultimately sparked a revolution in our understanding of nuclear physics. However, studies with radioactive isomer beams are sparse and have often required sophisticated apparatuses coupled with the technologies of ground-state beams due to typical mass differences on the order of hundreds of keV and vastly different lifetimes for isomers. We present an application of a isomeric beam of 26mAl to one of the most famous observables in nuclear astrophysics: galactic 26Al. The characteristic decay of 26Al in the Galaxy was the first such specific radioactivity to be observed originating from outside the Earth some four decades ago. We present a newly-developed, novel technique to probe the structure of low-spin states in 27Si. Using the Center for Nuclear Study low-energy radioisotope beam separator (CRIB), we report on the measurement of 26mAl proton resonant elastic scattering conducted with a thick target in inverse kinematics. The preliminary results of this on-going study are presented.
Universality of low-energy Rashba scattering
Hutchinson, Joel; Maciejko, Joseph
2017-09-01
We investigate the scattering of a quantum particle with a two-dimensional (2D) Rashba spin-orbit coupled dispersion off of circularly symmetric potentials. As the energy of the particle approaches the bottom of the lowest spin-split band, i.e., the van Hove singularity, earlier work has shown that scattering off of an infinite circular barrier exhibits a number of features unusual from the point of view of conventional 2D scattering theory: the low-energy S matrix is independent of the range of the potential, all partial waves contribute equally, the differential cross section becomes increasingly anisotropic and 1D-like, and the total cross section exhibits quantized plateaus. Via a nonperturbative determination of the T matrix and an optical theorem which we prove here, we show that this behavior is universal for Rashba scattering off of any circularly symmetric, spin independent, finite-range potential. This is relevant both for impurity scattering in the noninteracting limit as well as for short-range two-particle scattering in the interacting problem.
Elastic proton-proton scattering: Excitation functions from 0.45 to 2.5 GeV
Hinterberger, F.; Bauer, F.; Bisplinghoff, J.; Büßer, K.; Busch, M.; Colberg, T.; Demirörs, L.; Dahl, C.; Eversheim, P. D.; Eyser, O.; Felden, O.; Gebel, R.; Greiff, J.; Jonas, E.; Krause, H.; Lehmann, C.; Lindlein, J.; Maier, R.; Meinerzhagen, A.; Pauli, C.; Prasuhn, D.; Rohdjeß, H.; Rosendaal, D.; von Rossen, P.; Schirm, N.; Scobel, W.; Ulbrich, K.; Weise, E.; Wolf, T.; Ziegler, R.
Excitation functions of the differential cross sections {dσ}/{dgw}, analyzing powers AN and spin correlation parameters ANN, ASS and ASL have been measured with internal targets at the Cooler Synchrotron COSY. Data were taken continously during the acceleration and deceleration of the internal beam for kinetic energies between 450 and 2500 MeV and scattering angles 30° ⩽ σ cm ⩽ 90°. Details of the experimental method are presented. The results provide excitation functions and angular distributions of high precision and internal consistency. No evidence for narrow structures are found. Upper limits on the coupling of narrow resonances to elastic scattering in the mass range √ s = 2.2…2.8 GeV are deduced. The data have significant impact on phase shift solutions.
Measurement of Deuteron Tensor Polarization in Elastic Electron Scattering
Energy Technology Data Exchange (ETDEWEB)
Gustafsson, Kenneth K. [Univ. of Maryland, College Park, MD (United States)
2000-01-01
Nuclear physics traces it roots back to the very beginning of the last century. The concept of the nuclear atom was introduced by Rutherford around 1910. The discovery of the neutron Chadwick in 1932 gave us the concept of two nucleons: the proton and the neutron. The Jlab electron accelerator with its intermediate energy high current continuous wave beam combined with the Hall C high resolution electron spectrometer and a deutron recoil polarimeter provided experiment E94018 with the opportunity to study the deuteron electomagnetic structure, in particular to measure the tensor polarization observable t_{20}, at high four momentum transfers than ever before. This dissertation presents results of JLab experiment E94018.
Measurement of Muon Antineutrino Quasi-Elastic Scattering on a Hydrocarbon Target at E_{\
Fields, L; Aliaga, L; Altinok, O; Bodek, A; Boehnlein, D; Bradford, R; Brooks, W K; Budd, H; Butkevich, A; Caicedo, D A M; Castromonte, C M; Christy, M E; da Motta, H; Damiani, D S; Danko, I; Datta, M; Day, M; DeMaat, R; Devan, J; Diaz, G A; Dytman, S A; Eberly, B; Edmondson, D A; Felix, J; Fitzpatrick, T; Fiorentini, G A; Gago, A M; Gallagher, H; Gobbi, B; Gran, R; Harris, D A; Higuera, A; Howley, I J; Hurtado, K; Jerkins, M; Kafka, T; Kanter, M O; Keppel, C; Kordosky, M; Krajeski, A H; Kulagin, S A; Le, T; Leister, A G; Maggi, G; Maher, E; Manly, S; Mann, W A; Marshall, C M; McFarland, K S; McGivern, C L; McGowan, A M; Mislivec, A; Morfin, J G; Mousseau, J; Naples, D; Nelson, J K; Niculescu, G; Niculescu, I; Ochoa, N; O'Connor, C D; Osta, J; Palomino, J L; Paolone, V; Park, J; Patrick, C E; Perdue, G N; Pena, C; Rakotondravohitra, L; Ransome, R D; Ray, H; Ren, L; Rodrigues, P A; Sassin, K E; Schellman, H; Schmitz, D W; Schneider, R M; Schulte, E C; Sedita, P; Simon, C; Snider, F D; Snyder, M C; Sobczyk, J T; Salinas, C J Solano; Tagg, N; Tan, W; Tice, B G; Tzanakos, G; Velasquez, J P; Walding, J; Walton, T; Wolcott, J; Wolthuis, B A; Zavala, G; Zhang, D; Ziemer, B P
2013-01-01
We have isolated muon anti-neutrino charged-current quasi-elastic interactions occurring in the segmented scintillator tracking region of the MINERvA detector running in the NuMI neutrino beam at Fermilab. We measure the flux-averaged differential cross-section, d{\\sigma}/dQ^2, and compare to several theoretical models of quasi-elastic scattering. Good agreement is obtained with a model where the nucleon axial mass, M_A, is set to 0.99 GeV/c^2 but the nucleon vector form factors are modified to account for the observed enhancement, relative to the free nucleon case, of the cross-section for the exchange of transversely polarized photons in electron-nucleus scattering. Our data at higher Q^2 favor this interpretation over an alternative in which the axial mass is increased.
Transverse Beam Spin Asymmetries in Forward-Angle Elastic Electron-Proton Scattering
Armstrong, D S; Asaturyan, R; Averett, T; Bailey, S L; Batigne, G; Beck, D H; Beise, E J; Benesch, J; Bimbot, L; Birchall, J; Biselli, A; Bosted, P; Boukobza, E; Breuer, H; Carlini, R; Carr, R; Chant, N; Chao, Y C; Chattopadhyay, S; Clark, R; Covrig, S; Cowley, A; Dale, D; Davis, C; Falk, W; Finn, J M; Forest, T; Franklin, G; Furget, C; Gaskell, D; Grames, J; Griffioen, K A; Grimm, K; Guillon, B; Guler, H; Hannelius, L; Hasty, R; Hawthorne Allen, A; Horn, T; Johnston, K; Jones, M; Kammel, P; Kazimi, R; King, P M; Kolarkar, A; Korkmaz, E; Korsch, W; Kox, S; Kühn, J; Lachniet, J; Lee, L; Lenoble, J; Liatard, E; Liu, J; Loupias, B; Lung, A; Marchand, D; Martin, J W; McFarlane, K W; McKee, D W; McKeown, R D; Merchez, F; Mkrtchyan, H; Moffit, B; Morlet, M; Nakagawa, I; Nakahara, K; Neveling, R; Niccolai, S; Ong, S; Page, S; Papavassiliou, V; Pate, S F; Phillips, S K; Pitt, M L; Poelker, M; Porcelli, T A; Quéméner, G; Quinn, B; Ramsay, W D; Rauf, A W; Real, J S; Roche, J; Roos, P; Rutledge, G A; Secrest, J; Simicevic, N; Smith, G R; Spayde, D T; Stepanyan, S; Stutzman, M; Sulkosky, V; Tadevosyan, V; Tieulent, R; Van de Wiele, J; Van Oers, W T H; Voutier, E; Vulcan, W; Warren, G; Wells, S P; Williamson, S E; Wood, S A; Yan, C; Yun, J; Zeps, V
2007-01-01
We have measured the beam-normal single-spin asymmetry in elastic scattering of transversely-polarized 3 GeV electrons from unpolarized protons at Q^2 values of 0.15 and 0.25 (GeV/c)^2 with results of A_n = -4.06 +- 0.99 (stat) +- 0.63 (syst) and A_n = -4.82 +- 1.87 (stat) +- 0.98 (syst) ppm. These results are inconsistent with calculations solely using the elastic nucleon intermediate state, and generally agree with calculations with significant inelastic hadronic intermediate state contributions. A_n provides a direct probe of the imaginary component of the 2-gamma exchange amplitude, the complete description of which is important in the interpretation of data from precision electron-scattering experiments.
Oh, Ju-Won
2016-07-04
Multiparameter full waveform inversion (FWI) applied to an elastic orthorhombic model description of the subsurface requires in theory a nine-parameter representation of each pixel of the model. Even with optimal acquisition on the Earth surface that includes large offsets, full azimuth, and multicomponent sensors, the potential for trade-off between the elastic orthorhombic parameters are large. The first step to understanding such trade-off is analysing the scattering potential of each parameter, and specifically, its scattering radiation patterns. We investigate such radiation patterns for diffraction and for scattering from a horizontal reflector considering a background isotropic model. The radiation patterns show considerable potential for trade-off between the parameters and the potentially limited resolution in their recovery. The radiation patterns of C11, C22, and C33 are well separated so that we expect to recover these parameters with limited trade-offs. However, the resolution of their recovery represented by recovered range of model wavenumbers varies between these parameters. We can only invert for the short wavelength components (reflection) of C33 while we can mainly invert for the long wavelength components (transmission) of the elastic coefficients C11 and C22 if we have large enough offsets. The elastic coefficients C13, C23, and C12 suffer from strong trade-offs with C55, C44, and C66, respectively. The trade-offs between C13 and C55, as well as C23 and C44, can be partially mitigated if we acquire P–SV and SV–SV waves. However, to reduce the trade-offs between C12 and C66, we require credible SH–SH waves. The analytical radiation patterns of the elastic constants are supported by numerical gradients of these parameters.
Wavefield separation by energy norm Born scattering
Sun, Bingbing
2017-08-17
In Reflection Based Waveform Inversion, the gradient is computed by cross-correlating the direct and Born scattered wavefield with their adjoints applied to the data residuals. In this case, the transmitted part of the Born scattered wavefield produces high wavenumber artifacts, which would harm the convergence of the inversion process. We propose an efficient Energy Norm Born Scattering (ENBS) to attenuate the transmission components of the Born modeling, and allow it to produce only reflections. ENBS is derived from the adjoint of the Energy Norm (inverse scattering) imaging condition and in order to get deeper insights of how this method works, we show analytically that given an image, in which reflectivity is represented by a Dirac delta function, ENBS attenuates transmission energy perfectly. We use numerical examples to demonstrate that ENBS works in both the time and the frequency domain. We also show that in reflection waveform inversion (RWI) the wave path constructed by ENBS would be cleaner and free of high wavenumber artifacts associated with conventional Born scattering.
Study of oxidized iron thin films by non-Rutherford elastic scattering
Energy Technology Data Exchange (ETDEWEB)
Jimenez-Villacorta, F. [Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Cientificas, Cantoblanco, 28049 Madrid (Spain)]. E-mail: felixjv@icmm.csic.es; Munoz-Martin, A. [Centro de Microanalisis de Materiales, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Prieto, C. [Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Cientificas, Cantoblanco, 28049 Madrid (Spain)
2006-08-15
Rutherford and non-Rutherford elastic scattering analyses have been performed to characterize oxidized iron thin films grown by sputtering. The oxygen depth profiles along the thickness of all the samples have been studied in order to unravel the oxidation process of these samples. The oxygen concentration along the film was related to the sample preparation parameters, resulting in a strong dependence of oxygen depth profile on the substrate temperature during deposition.
Energy Technology Data Exchange (ETDEWEB)
Aksouh, F
2002-12-01
The elastic proton scattering from the halo nuclei {sup 6}He and {sup 8}He was investigated in inverse kinematics at energies around 700 MeV/u with the aim to deduce the differential cross sections for the region of high momentum transfer, covering the first diffraction minimum. For this purpose, a liquid-hydrogen target was specially developed and used for the first time allowing to obtain low-background data as compared to commonly used targets made from C-H compounds. Previous data taken in the region of small momentum transfer were sensitive to the size and the peripheral shape of the total nuclear matter density distribution but not to the inner part. The present data allow for a more detailed insight in the structure of the alike core in {sup 6,8}He through a better determination of the matter density distributions. Several density distributions calculated from different microscopic models were used to derive elastic scattering cross sections which are compared with the obtained data. (author)
Measurement of np elastic scattering spin-spin correlation parameters at 484, 634, and 788 MeV
Energy Technology Data Exchange (ETDEWEB)
Garnett, R.W.
1989-03-01
The spin-spin correlation parameters C/sub LL/ and C/sub SL/ were measured for np elastic scattering at the incident neutron kinetic energy of 634 MeV. Good agreement was obtained with previously measured data. Additionally, the first measurement of the correlation parameter C/sub SS/ was made at the three energies, 484, 634, and 788 MeV. It was found that the new values, in general, do not agree well with phase shift predictions. A study was carried out to determine which of the isospin-0 partial waves will be affected by this new data. It was found that the /sup 1/P/sub 1/ partial wave will be affected significantly at all three measurement energies. At 634 and 788 MeV, the /sup 3/S/sub 1/ phase shifts will also change. 29 refs., 21 figs., 16 tabs.
Interference effect in elastic parton energy loss in a finitemedium
Energy Technology Data Exchange (ETDEWEB)
Wang, Xin-Nian
2005-04-18
Similar to the radiative parton energy loss due to gluonbremsstrahlung, elastic energy loss of a parton undergoing multiplescattering in a finite medium is demonstrated to be sensitive tointerference effect. The interference between amplitudes of elasticscattering via a gluon exchange and that of gluon radiation reduces theeffective elastic energy loss in a finite medium and gives rise to anon-trivial length dependence. The reduction is most significant for apropagation length L<4/\\pi T in a medium with a temperature T. Thoughthe finite size effect is not significant for the average partonpropagation in the most central heavy-ion collisions, it will affect thecentrality dependence of its effect on jet quenching.
Polarization in elastic $\\pi^{-}p$ scattering at 16 momenta between 865 and 2732 MeV/c
Albrow, M G; Bošnjakovič, B; Daum, C; Erné, F C; Kimura, Y; Lagnaux, J P; Sens, Johannes C; Udo, Fred
1972-01-01
Polarization distributions and differential cross section data for elastic scattering of negative pions on protons between 865 and 2732 MeV/c are presented. They are compared with published phase-shift analyses. (17 refs).
Low energy cross sections for electron scattering from tetrafluoroallene
Gupta, Dhanoj; Choi, Heechol; Song, Mi-Young; Chakrabarti, Kalyan; Yoon, Jung-Sik
2017-08-01
We report elastic, total, excitation, differential and momentum-transfer cross sections for scattering of low-energy electrons by tetrafluoroallene (C3F4) using the close-coupling (CC) approximation in the R-matrix method with Quantemol-N. We have tested various target models initially to check for the convergence of the result and the final results are provided with the best target model. We have detected shape resonances of symmetry 2 E(2B1,2B2) at 3.08 eV and 3.71 eV with a close-coupling and static exchange models which is seen as a sharp feature in the elastic and momentum transfer cross sections. We also detected other resonances of symmetry 2 E at 11.26 eV and of symmetry 2A2 at 11.12 eV below the ionization threshold of the target respectively. The present elastic and total cross sections are compared with the elastic and total cross sections of allene (C3H4), propene (C3H6) and hexafluoropropene (C3F6) as there were no results available for C3F4. The effect of fluorination is clearly seen with the shape resonance for C3F4 getting slightly shifted to higher energies compared to allene. Finally, we also report the ionization cross section calculated using the Binary-Encounter Bethe (BEB) method. The present calculation is a maiden attempt to find cross sections for C3F4 molecule which could be useful for fluorocarbon plasma modeling.
Uesaka, T; Gurchin, Yu V; Isupov, A Yu; Itoh, K; Janek, M; Karachuk, J T; Kawabata, T; Khrenov, A N; Kiselev, A S; Kizka, V; Kliman, J; Krasnov, V A; Livanov, A N; Maeda, Y; Malakhov, A I; Matoucek, V; Morhac, M; Nedev, S; Rangelov, S; Reznikov, S G; Sakaguchi, S; Sakai, H; Sasamoto, Y; Sekiguchi, K; Suda, K; Turzó, I; Vasiliev, T A; Wakui, T
2005-01-01
A new high-energy beam polarimeter is proposed for the Nuclotron using Internal Target Station. This polarimeter based on the measurement of the asymmetry for the $d-p$ elastic scattering will allow one to measure both vector and tensor components of the deuteron beam polarization simultaneously. For that purpose the measurement of analyzing powers for the $d$--$p$ elastic scattering at energies $T_d$ = 0.88--2 GeV is proposed. The precise measurements of the deuteron analyzing powers over energy range $T_{d}$ = 300-2000 MeV can give an irreplaceable clue on the study of spin-dependence of three-nucleon forces.
Quark structure of the nucleon and angular asymmetry of proton-neutron hard elastic scattering.
Granados, Carlos G; Sargsian, Misak M
2009-11-20
We investigate an asymmetry in the angular distribution of hard elastic proton-neutron scattering with respect to the 90 degrees center of mass scattering angle and demonstrate that it's magnitude is related to the helicity-isospin symmetry of the quark wave function of the nucleon. Our estimate of the asymmetry within the quark-interchange model of hard scattering demonstrates that the quark wave function of a nucleon based on the exact SU(6) symmetry predicts an angular asymmetry opposite to that of experimental observations. We found that the quark wave function based on the diquark picture of the nucleon produces a correct asymmetry. Comparison with the data allowed us to show that the vector diquarks contribute around 10% in the nucleon wave function and they are in negative phase relative to the scalar diquarks. These observations are essential in constraining QCD models of a nucleon.
Energy Technology Data Exchange (ETDEWEB)
Caciolli, A.; Calzolai, G. [Department of Physics, University of Florence and INFN, Florence, via Sansone 1, I-50019 Sesto Fiorentino (Firenze) (Italy); Chiari, M. [Department of Physics, University of Florence and INFN, Florence, via Sansone 1, I-50019 Sesto Fiorentino (Firenze) (Italy)], E-mail: chiari@fi.infn.it; Climent-Font, A.; Garcia, G. [CMAM, Universidad Autonoma de Madrid, Madrid (Spain); Lucarelli, F.; Nava, S. [Department of Physics, University of Florence and INFN, Florence, via Sansone 1, I-50019 Sesto Fiorentino (Firenze) (Italy)
2008-04-15
Differential cross-sections for proton elastic scattering on sodium and for {gamma}-ray emission from the reactions {sup 23}Na(p,p'{gamma}){sup 23}Na (E{sub {gamma}} = 440 keV and E{sub {gamma}} = 1636 keV) and {sup 23}Na(p,{alpha}'{gamma}){sup 20}Ne (E{sub {gamma}} = 1634 keV) were measured for proton energies from 2.2 to 5.2 MeV using a 63 {mu}g/cm{sup 2} NaBr target evaporated on a self-supporting thin C film. The {gamma}-rays were detected by a 38% relative efficiency Ge detector placed at an angle of 135 deg. with respect to the beam direction, while the backscattered protons were collected by a Si surface barrier detector placed at a scattering angle of 150 deg. Absolute differential cross-sections were obtained with an overall uncertainty estimated to be better than {+-}6.0% for elastic scattering and {+-}12% for {gamma}-ray emission, at all the beam energies. To provide a convincing test of the overall validity of the measured elastic scattering cross-section, thick target benchmark experiments at several proton energies are presented.
Elastic scattering of polarized protons on helium three at 800 MeV
Energy Technology Data Exchange (ETDEWEB)
Azizi, A.
1985-07-01
A set of spin dependent parameters and cross sections has been measured for polarized p-/sup 3/He elastic scattering over the range of q .7 to 4.2 fm/sup -1/. The experiment was done at the Los Alamos Meson Physics Facility (LAMPF) using the High Resolution Spectrometer (HRS) with a polarized proton beam at .8 GeV. The focal plane polarimeter of the HRS was used to determine the spin direction of the scattered proton. Since /sup 3/He is one of the simplest nuclei, polarized p-/sup 3/He scattering provides a very sensitive test of multiple scattering theories. The theoretical analysis was done by using two different wave functions for /sup 3/He as input to the multiple scattering theory. The theoretical calculations and experimental data together will give us useful information about nucleon-nucleon amplitudes and also help us to obtain a better understanding of the scattering process. 68 refs., 55 figs., 9 tabs.
The Measurement Of The Quasi-elastic Neutrino-nucleon Scattering Cross Section At The Tevatron
Suwonjandee, N
2004-01-01
The quasi-elastic neutrino nucleon cross section measurement has been measured in the low energy region less than 100 GeV. The data agree well with the model proposed by C. H. Llewellyn Smith. This model predicts that the quasi-elastic cross section should be constant in the high energy region. The NuTeV experiment at Fermilab provides data which allows us to measure the quasi-elastic cross section for both neutrinos and anti- neutrinos at high energy. We find that sNucleonqen = 0.94 ± 0.03(stat.) ± 0.07( syst.), and sNucleonqen &d1; = 1.12 ± 0.04(stat.) ± 0.10( syst.) for neutrino and anti-neutrino, respectively.
Study of forward elastic pp scattering at √ i>s> = 8 TeV with the ALFA detector
DEFF Research Database (Denmark)
Stark, Simon Holm
The elastic proton-proton scattering data analyzed in this thesis was taken at the LHC with the ALFA detector at sqrt(s) = 8 TeV with a beta* collision optics which gave access to the Coulomb-Nuclear-Interference region. An improved procedure was used to fit the observed number of elastic events ...
Inelastic pion scattering by /sup 13/C at low energies
Energy Technology Data Exchange (ETDEWEB)
Mitchell, J.H.
1987-03-01
Angular distributions for inelastically scattered pions were obtained for several states in /sup 13/C at an incident energy of 65 MeV. The data include results from both ..pi../sup +/ and ..pi../sup -/ measurements. In addition, ..pi../sup -/ measurements were made at T/sub ..pi../ = 50 MeV at one angle to give a two point fixed-q excitation function. The data are compared to theory and the data of others. As might be expected, medium corrections are shown to be considerably more important at low energies than at resonance. This is true for inelastic transitions of multipolarity 0,2 and 3. Parameters derived from an analysis of elastic pion scattering and SCX data also provide an adequate description of the inelastic transitions. The charge asymmetry in the cross sections for the 9/2/sup +/ state that was seen at resonance persists at these energies. This result is consistent with an impulse approximation treatment of the spin-flip amplitude. This is true even though the incoming energy of the pions is far below the range where the validity of an impulse treatment is expected. 65 refs., 45 figs.
Henderson, B. S.; Ice, L. D.; Khaneft, D.; O'Connor, C.; Russell, R.; Schmidt, A.; Bernauer, J. C.; Kohl, M.; Akopov, N.; Alarcon, R.; Ates, O.; Avetisyan, A.; Beck, R.; Belostotski, S.; Bessuille, J.; Brinker, F.; Calarco, J. R.; Carassiti, V.; Cisbani, E.; Ciullo, G.; Contalbrigo, M.; de Leo, R.; Diefenbach, J.; Donnelly, T. W.; Dow, K.; Elbakian, G.; Eversheim, P. D.; Frullani, S.; Funke, Ch.; Gavrilov, G.; Gläser, B.; Görrissen, N.; Hasell, D. K.; Hauschildt, J.; Hoffmeister, Ph.; Holler, Y.; Ihloff, E.; Izotov, A.; Kaiser, R.; Karyan, G.; Kelsey, J.; Kiselev, A.; Klassen, P.; Krivshich, A.; Lehmann, I.; Lenisa, P.; Lenz, D.; Lumsden, S.; Ma, Y.; Maas, F.; Marukyan, H.; Miklukho, O.; Milner, R. G.; Movsisyan, A.; Murray, M.; Naryshkin, Y.; Perez Benito, R.; Perrino, R.; Redwine, R. P.; Rodríguez Piñeiro, D.; Rosner, G.; Schneekloth, U.; Seitz, B.; Statera, M.; Thiel, A.; Vardanyan, H.; Veretennikov, D.; Vidal, C.; Winnebeck, A.; Yeganov, V.; Olympus Collaboration
2017-03-01
The OLYMPUS Collaboration reports on a precision measurement of the positron-proton to electron-proton elastic cross section ratio, R2 γ , a direct measure of the contribution of hard two-photon exchange to the elastic cross section. In the OLYMPUS measurement, 2.01 GeV electron and positron beams were directed through a hydrogen gas target internal to the DORIS storage ring at DESY. A toroidal magnetic spectrometer instrumented with drift chambers and time-of-flight scintillators detected elastically scattered leptons in coincidence with recoiling protons over a scattering angle range of ≈20 ° to 80°. The relative luminosity between the two beam species was monitored using tracking telescopes of interleaved gas electron multiplier and multiwire proportional chamber detectors at 12°, as well as symmetric Møller or Bhabha calorimeters at 1.29°. A total integrated luminosity of 4.5 fb-1 was collected. In the extraction of R2 γ, radiative effects were taken into account using a Monte Carlo generator to simulate the convolutions of internal bremsstrahlung with experiment-specific conditions such as detector acceptance and reconstruction efficiency. The resulting values of R2 γ, presented here for a wide range of virtual photon polarization 0.456 <ɛ <0.978 , are smaller than some hadronic two-photon exchange calculations predict, but are in reasonable agreement with a subtracted dispersion model and a phenomenological fit to the form factor data.
Energy Technology Data Exchange (ETDEWEB)
Henderson, B.S. [Massachusetts Institute of Technology, Cambridge, MA (United States); Ice, L.D. [Arizona State Univ., Tempe, AZ (United States); Khaneft, D. [Mainz Univ. (Germany); Collaboration: OLYMPUS Collaboration; and others
2016-12-15
The OLYMPUS collaboration reports on a precision measurement of the positron-proton to electron-proton elastic cross section ratio, R{sub 2γ}, a direct measure of the contribution of hard two- photon exchange to the elastic cross section. In the OLYMPUS measurement, 2.01 GeV electron and positron beams were directed through a hydrogen gas target internal to the DORIS storage ring at DESY. A toroidal magnetic spectrometer instrumented with drift chambers and time-of-flight scintillators detected elastically scattered leptons in coincidence with recoiling protons over a scattering angle range of ∼20 to 80 . The relative luminosity between the two beam species was monitored using tracking telescopes of interleaved GEM and MWPC detectors at 12 , as well as symmetric Moeller/Bhabha calorimeters at 1.29 . A total integrated luminosity of 4.5 fb{sup -1} was collected. In the extraction of R{sub 2γ}, radiative effects were taken into account using a Monte Carlo generator to simulate the convolutions of internal bremsstrahlung with experiment-specific conditions such as detector acceptance and reconstruction efficiency. The resulting values of R{sub 2γ}, presented here for a wide range of virtual photon polarization 0.456<ε<0.978, are smaller than some hadronic two-photon exchange calculations predict, but are in reasonable agreement with a subtracted dispersion model and a phenomenological fit to the form factor data.
Henderson, B S; Khaneft, D; O'Connor, C; Russell, R; Schmidt, A; Bernauer, J C; Kohl, M; Akopov, N; Alarcon, R; Ates, O; Avetisyan, A; Beck, R; Belostotski, S; Bessuille, J; Brinker, F; Calarco, J R; Carassiti, V; Cisbani, E; Ciullo, G; Contalbrigo, M; De Leo, R; Diefenbach, J; Donnelly, T W; Dow, K; Elbakian, G; Eversheim, P D; Frullani, S; Funke, Ch; Gavrilov, G; Gläser, B; Görrissen, N; Hasell, D K; Hauschildt, J; Hoffmeister, Ph; Holler, Y; Ihloff, E; Izotov, A; Kaiser, R; Karyan, G; Kelsey, J; Kiselev, A; Klassen, P; Krivshich, A; Lehmann, I; Lenisa, P; Lenz, D; Lumsden, S; Ma, Y; Maas, F; Marukyan, H; Miklukho, O; Milner, R G; Movsisyan, A; Murray, M; Naryshkin, Y; Benito, R Perez; Perrino, R; Redwine, R P; neiro, D Rodríguez Pi\\; Rosner, G; Schneekloth, U; Seitz, B; Statera, M; Thiel, A; Vardanyan, H; Veretennikov, D; Vidal, C; Winnebeck, A; Yeganov, V
2016-01-01
The OLYMPUS collaboration reports on a precision measurement of the positron-proton to electron-proton elastic cross section ratio $R_{2\\gamma}$, a direct measure of the contribution of hard two-photon exchange to the elastic cross section. In the OLYMPUS measurement, 2.01 GeV electron and positron beams were directed through a hydrogen gas target internal to the DORIS storage ring at DESY. A toroidal magnetic spectrometer instrumented with drift chambers and time-of-flight scintillators detected elastically scattered leptons in coincidence with recoiling protons over a scattering angle range of $\\approx 20^\\circ$ to $80^\\circ$. The relative luminosity between the two beam species was monitored using tracking telescopes of interleaved GEM and MWPC detectors at $12^\\circ$, as well as symmetric M{\\o}ller/Bhabha calorimeters at $1.29^\\circ$. A total integrated luminosity of 4.5 fb$^{-1}$ was collected. In the extraction of $R_{2\\gamma}$, radiative effects were taken into account using a Monte Carlo generator to ...
Anghinolfi, F; Barrillon, P; Blanchot, G; Blin, S; Braem, André; de La Taille, C; Di Girolamo, B; Efthymiopoulos, I; Faustino, J; Fournier, D; Franz, S; Grafström, P; Gurriana, L; Haguenauer, M; Hedberg, V; Heller, M; Hoffmann, S; Iwanski, W; Joram, C; Kocnár, A; Lavigne, B; Lundberg, B; Maio, A; Maneira, M J P; Mapelli, A; Marques, C; Mjörnmark, U; Conde-Muíño, P; Puzo, P; Rijssenbeek, M; Saraiva, J G; Seguin-Moreau, N; Soares, S; Stenzel, H; Thioye, M; Varouchas, D; Vorobel, V
2007-01-01
A scintillating fibre tracker is proposed to measure elastic proton scattering at very small angles in the ATLAS experiment at CERN. The tracker will be located in so-called Roman Pot units at a distance of 240 m on each side of the ATLAS interaction point. An initial validation of the design choices was achieved in a beam test at DESY in a relatively low energy electron beam and using slow off-the-shelf electronics. Here we report on the results from a second beam test experiment carried out at CERN, where new detector prototypes were tested in a high energy hadron beam, using the first version of the custom designed front-end electronics. The results show an adequate tracking performance under conditions which are similar to the situation at the LHC. In addition, the alignment method using so-called overlap detectors was studied and shown to have the expected precision.
Energy-dependent microscopic optical potential for scattering of nucleons on light nuclei
Energy Technology Data Exchange (ETDEWEB)
Farag, M.Y.H.; Esmael, E.H. [Cairo University, Physics Department, Faculty of Science, Giza (Egypt); Maridi, H.M. [Cairo University, Physics Department, Faculty of Science, Giza (Egypt); Taiz University, Physics Department, Faculty of Applied Science, Taiz (Yemen)
2014-06-15
We present an energy-dependent microscopic optical model potential for elastic scattering of nucleons on light nuclei. The single-folding model is used for the real part of the optical potential (OP), while the imaginary part is derived within the high-energy approximation theory. The energy dependence of the OP is determined from the parameterization of the volume integrals those calculated from the best-fit OP that fit the experimental data of the cross sections and analyzing powers. This energy-dependent OP is successfully applied to analyze the proton elastic scattering of {sup 4,6,i8}He, {sup 6,7}Li, and {sup 9,10}Be nuclei at low and intermediate incident energies up to 200MeV/nucleon. (orig.)
Kreutzfeldt, Kristof; Stenzel, Hasko
The ATLAS experiment with the ALFA sub-detector, provides a unique opportunity to measure elastic proton--proton scattering at the LHC at a centre-of-mass energy of $\\sqrt{s} = 7$ TeV, that has never been reached before. The ALFA detector is a tracking detector housed in Roman Pots, which makes it possible to measure elastically scattered protons down to very small scattering angles. From the proton tracks, measured during a LHC fill with special $\\beta^{*} = 90$ m beam optics, the differential elastic cross-section as a function of the four-momentum transfer squared $t$ is determined, and the total hadronic cross-section $\\sigma_\\text{tot}$, the nuclear slope parameter $B$ and further derived quantities are extracted by utilizing the optical theorem. The total hadronic cross-section is a fundamental parameter of strong interaction depending on the centre-of-mass energy. It has been measured for more than 50 years at different energies and accelerators, where a rise with energy was observed. A newly developed...
Quasi-Elastic Neutron Scattering Studies of the Slow Dynamics of Supercooled and Glassy Aspirin
Energy Technology Data Exchange (ETDEWEB)
Zhang, Yang [ORNL; Tyagi, M. [NCNR and University of Maryland; Mamontov, Eugene [ORNL; Chen, Sow-hsin H [ORNL
2011-01-01
Aspirin, also known as acetylsalicylic acid (ASA), is not only a wonderful drug, but also a good glass former. Therefore, it serves as an important molecular system to study the near-arrest and arrested phenomena. In this paper, a high-resolution quasi-elastic neutron scattering (QENS) technique is used to investigate the slow dynamics of supercooled liquid and glassy aspirin from 410 K down to 350 K. The measured QENS spectra can be analyzed with a stretched exponential model. We find that (i) the stretched exponent (Q) is independent of the wave vector transfer Q in the measured Q-range, and (ii) the structural relaxation time (Q) follows a power law dependence on Q. Consequently, the Q-independent structural relaxation time 0 can be extracted for each temperature to characterize the slow dynamics of aspirin. The temperature dependence of 0 can be fitted with the mode coupling power law, the Vogel-Fulcher-Tammann equation and a universal equation for fragile glass forming liquids recently proposed by M. Tokuyama in the measured temperature range. The calculated dynamic response function T(Q,t) using the experimentally determined self-intermediate scattering function of the hydrogen atoms of aspirin shows a direct evidence of the enhanced dynamic fluctuations as the aspirin is increasingly supercooled, in agreement with the fixed-time mean squared displacement x2 and non-Gaussian parameter 2 extracted from the elastic scattering.
Quasi-elastic neutron scattering studies of the slow dynamics of supercooled and glassy aspirin
Zhang, Yang; Tyagi, Madhusudan; Mamontov, Eugene; Chen, Sow-Hsin
2012-02-01
Aspirin, also known as acetylsalicylic acid (ASA), is not only a wonderful drug, but also a good glass former. Therefore, it serves as an important molecular system to study the near-arrest and arrested phenomena. In this paper, a high-resolution quasi-elastic neutron scattering (QENS) technique is used to investigate the slow dynamics of supercooled liquid and glassy aspirin from 410 down to 350 K. The measured QENS spectra can be analyzed with a stretched exponential model. We find that (i) the stretched exponent β(Q) is independent of the wavevector transfer Q in the measured Q range and (ii) the structural relaxation time τ(Q) follows a power-law dependence on Q. Consequently, the Q-independent structural relaxation time τ0 can be extracted for each temperature to characterize the slow dynamics of aspirin. The temperature dependence of τ0 can be fitted with the mode-coupling power law, the Vogel-Fulcher-Tammann equation and a universal equation for fragile glass forming liquids recently proposed by Tokuyama in the measured temperature range. The calculated dynamic response function χT(Q, t) using the experimentally determined self-intermediate scattering function of the hydrogen atoms of aspirin shows direct evidence of the enhanced dynamic fluctuations as the aspirin is increasingly supercooled, in agreement with the fixed-time mean squared displacement langx2rang and the non-Gaussian parameter α2 extracted from the elastic scattering.
Entanglement creation in low-energy scattering
Energy Technology Data Exchange (ETDEWEB)
Weder, Ricardo [Institut National de Recherche en Informatique et en Automatique Paris-Rocquencourt, Projet POEMS, Domaine de Voluceau-Rocquencourt, BP 105, F-78153, Le Chesnay Cedex (France)
2011-12-15
We study the entanglement creation in the low-energy scattering of two particles in three dimensions, for a general class of interaction potentials that are not required to be spherically symmetric. The incoming asymptotic state, before the collision, is a product of two normalized Gaussian states. After the scattering, the particles are entangled. We take as a measure of the entanglement the purity of one of them. We provide a rigorous explicit computation, with error bound, of the leading order of the purity at low energy. The entanglement depends strongly on the difference of the masses. It takes its minimum when the masses are equal, and it increases rapidly with the difference of the masses. It is quite remarkable that the anisotropy of the potential gives no contribution to the leading order of the purity, in spite of the fact that entanglement is a second-order effect.
High-Energy Compton Scattering Light Sources
Hartemann, Fred V; Barty, C; Crane, John; Gibson, David J; Hartouni, E P; Tremaine, Aaron M
2005-01-01
No monochromatic, high-brightness, tunable light sources currently exist above 100 keV. Important applications that would benefit from such new hard x-ray sources include: nuclear resonance fluorescence spectroscopy, time-resolved positron annihilation spectroscopy, and MeV flash radiography. The peak brightness of Compton scattering light sources is derived for head-on collisions and found to scale with the electron beam brightness and the drive laser pulse energy. This gamma 2
Measurement of elastic. nu. /sub. mu. / and nu-bar/sub. mu. / scattering on protons
Energy Technology Data Exchange (ETDEWEB)
Coteus, P.; Diesburg, M.; Fine, R.; Lee, W.; Sokolsky, P.; Brown, R.; Fuess, S.; Nienaber, P.; O' Halloran, T. Jr.; Lee, Y.Y.
1981-09-01
We have measured elastic ..nu../sub ..mu../ and nu-bar/sub ..mu../ scattering on protons at the Brookhaven National Laboratory Alternating Gradient Synchrotron. We find R/sub NC/ = sigma(nu-bar/sub ..mu../p..-->..nu-bar/sub ..mu../p) / sigma(..nu../sub ..mu../p..--> nu../sub ..mu../p) = 0.44 +- 0.12 and R/sub numu/ = sigma(..nu../sub ..mu../p..--> nu../sub ..mu../p)/sigma(..nu../sub ..mu../n..--> mu../sup -/p) = 0.11 +- 0.03. The elastic Q/sup 2/ distribution is in good agreement with present knowledge of form factors and the Weinberg-Salam model. We find sin/sup 2/theta/sub W/ = 0.26 +- 0.06.
Elastic scattering of a proton-halo nucleus: {sup 8}B+{sup 58}Ni
Energy Technology Data Exchange (ETDEWEB)
Aguilera, E. F.; Martinez Q, E.; Rosales, P.; Lizcano, D.; Gomez C, A. [Departamento de Aceleradores, ININ, La Marquesa, 52750 Estado de Mexico (Mexico); Kolata, J. J.; Lamm, L. O. [Physics Department, University of Notre Dame, Notre Dame, 46556-5670 Indiana (United States); Guimaraes, V.; Lichtenthaler, R.; Camargo, O. [Instituto de Fisica, Universidade de Sao Paulo, P. O. Box 66318, 05389-970 Sao Paulo (Brazil); Becchetti, F. D.; Jiang, H. [Physics Department, University of Michigan, 48109-1120 Michigan (United States); DeYoung, P. A.; Mears, P. J. [Physics Department, Hope College, Holland, 49422-9000 Michigan (United States)]. e-mail: efar@nuclear.inin.mx
2008-12-15
The elastic channel of the {sup 8}B+{sup 58}Ni system has been measured at energies around the Coulomb barrier. An optical potential fi to the experimental angular distributions is obtained. The total reaction cross section consistent with the obtained potential is reported and possible deviations from normal behavior are discussed. (Author)
Thermoelastic waves without energy dissipation in an elastic plate to ...
African Journals Online (AJOL)
The linear theory of thermoelasticity without energy dissipation for isotropic and homogeneous materials is employed to study waves in an elastic plate. The waves are assumed to arise out of a ramp-type stress on the plate's boundary which is maintained at constant temperature. Laplace transforms are used to solve the ...
Short Range Correlations in Nuclei at Large xbj through Inclusive Quasi-Elastic Electron Scattering
Energy Technology Data Exchange (ETDEWEB)
Ye, Zhihong [Univ. of Virginia, Charlottesville, VA (United States)
2013-12-01
The experiment, E08-014, in Hall-A at Jefferson Lab aims to study the short-range correlations (SRC) which are necessary to explain the nuclear strength absent in the mean field theory. The cross sections for 2H, 3He, 4He, 12C, 40Ca and 48Ca, were measured via inclusive quasi-elastic electron scattering from these nuclei in a Q2 range between 0.8 and 2.8 (GeV/c)^{2} for x>1. The cross section ratios of heavy nuclei to 2H were extracted to study two-nucleon SRC for 1
Tensor Analyzing Powers for Quasi-Elastic Electron Scattering from Deuterium
Zhou, Z L; Ferro-Luzzi, M; Passchier, E; Alarcon, R; Anghinolfi, M; Arenhövel, H; Van Bommel, R; Botto, T; Van den Brand, J F J; Bulten, H J; Choi, S; Comfort, J; Dolfini, S M; Ent, R; Gaulard, C; Higinbotham, D W; De Jager, C W; Konstantinov, E S; Lang, J; Leidemann, W; De Lange, D J; Miller, M A; Lenko, D N; Papadakis, N H; Passchier, I; Poolman, H R; Popov, S G; Rachek, Igor A; Ripani, M; Six, E; Steijger, J J M; Taiuti, M; Unal, O; Vodinas, N P; De Vries, H
1999-01-01
We report on a first measurement of tensor analyzing powers in quasi-elastic electron-deuteron scattering at an average three-momentum transfer of 1.7 fm$^{-1}$. Data sensitive to the spin-dependent nucleon density in the deuteron were obtained for missing momenta up to 150 MeV/$c$ with a tensor polarized $^2$H target internal to an electron storage ring. The data are well described by a calculation that includes the effects of final-state interaction, meson-exchange and isobar currents, and leading-order relativistic contributions.
Garçon, M; Ahmidouch, A; Anklin, H; Arvieux, J; Ball, J; Beedoe, S; Beise, E J; Bimbot, L; Böglin, W; Breuer, H; Carlini, R; Chant, N S; Danagulyan, S; Dow, K; Ducret, J E; Dunne, J; Ewell, L A; Eyraud, L; Furget, C; Gilman, R; Glashausser, C; Gueye, P; Gustafsson, K K; Hafidi, K; Honegger, A; Jourdan, J; Kox, S; Kumbartzki, G; Lü, L; Lung, A; Mack, D; Markowitz, P; McIntyre, J; Meekins, D; Merchez, F; Mitchell, J; Möhring, R H; Mtingwa, S; Mrktchyan, H; Pitz, D; Qin, L; Ransome, R; Real, J S; Roos, P G; Rutt, P; Schmidt, W; Sawafta, R; Stepanyan, S; Stephenson, E J; Tieulent, R; Tomasi-Gustafsson, E; Turchinetz, W E; Vansyoc, K; Volmer, J; Voutier, E; Vulcan, W; Williamson, C; Wood, S A; Yan, C; Zhao, J; Zhao, W
1999-01-01
In elastic electron-deuteron scattering, the tensor polarization moments t sub 2 sub 0 , t sub 2 sub 1 and t sub 2 sub 2 , together with the unpolarized cross-sections, have been measured up to a momentum transfer of 1.8 (GeV/c) sup 2 , or 6.8 fm sup - sup 1. The experiment was performed at Jefferson Laboratory using the recoil deuteron polarimeter POLDER. Preliminary results are presented and discussed, especially in view of their significance concerning the applicability of perturbative QCD to this exclusive process.
Energy Technology Data Exchange (ETDEWEB)
Garcon, M; Ahmidouch, A; Anklin, H; Arvieux, J; Ball, J; Beedoe, S; Beise, E J; Bimbo, L; Boeglin, W; Breuer, H; Carlini, R; Chant, N S; Danagoulian, S; Dow, K; Ducret, J -E; Dunne, J; Ewell, L; Eyraud, L; Furget, C; Gilman, R; Glashausser, C; Gueye, P; Gustafsson, K; Hafidi, K; Honegger, A; Jourdan, J; Kox, S; Kumbartzki, G; Lu, L; Lung, A; Mack, D; Markowitz, P; McIntyre, J; Meekins, D; Merchez, F; Mitchell, J; Mohring, R; Mtingwa, S; Mrktchyan, H; Pitz, D; Qin, L; Ransome, R; Raoul, J -S; Roos, P G; Rutt, P; Schmidt, W; Sawafta, R; Stepanyan, S; Stephenson, R; Tieulent, R; Tomasi-Gustafsson, E
1999-07-01
In elastic electron-deuteron scattering, the tensor polarization moments t{sub 20}, t{sub 21} and t{sub 22}, together with the unpolarized cross-sections, have been measured up to a momentum transfer of 1.8 (GeV/c){sup 2}, or 6.8 fm{sup -1}. The experiment was performed at Jefferson Laboratory using the recoil deuteron polarimeter POLDER. Preliminary results are presented and discussed, especially in view of their significance concerning the applicability of perturbative QCD to this exclusive process.
Analysis of the Quasi-Elastic Scattering of Neutrons in Hydrogenous Liquids
Energy Technology Data Exchange (ETDEWEB)
Porohit, S.N. [Nuclear Science and Engineering Dept., Rensselaer Polytechnique Inst., Troy, NY (United States)
1966-11-15
A critical discussion of the quasi-elastic scattering of neutrons by incoherent (hydrogenous) liquids is presented. Using the line shape expression a comparative discussion of several phenomenological models has been carried out. Extension of the Singwi-Sjoelander zero phonon expression, for the jump-diffusion model, so as to include the one phonon expression has also been given. For a delayed diffusion model a complete treatment of S(K, {omega}) is presented. Along the lines of the macroscopic diffusion cooling, a microscopic diffusion cooling effect in fluids is speculated.
Chiral symmetry, constituent quarks and quasi-elastic electron-nucleus scattering
Henley, E. M.; Krein, G.
1989-11-01
The effects of chiral symmetry breaking are examined for quasi-elastic electron scattering on nuclei. Nucleons are assumed to be composed of constituent quarks with masses that depend on density. This density dependence is determined on the basis of the Nambu-Jona-Lasinio model. It is found that the effects of chiral symmetry breaking are in the right direction and the right order of magnitude to explain the discrepancies between theory and experiment. On leave from Departamento de Fisica, Universidade Federal de Santa Maria, 97100 Santa Maria, R.S., Brazil.
Rohdjeß, H.; Albers, D.; Bisplinghoff, J.; Bollmann, R.; Büßer, K.; Diehl, O.; Dohrmann, F.; Engelhardt, H.-P.; Eversheim, P. D.; Gasthuber, M.; Greiff, J.; Groß, A.; Groß-Hardt, R.; Hinterberger, F.; Igelbrink, M.; Langkau, R.; Maier, R.; Mosel, F.; Müller, M.; Münstermann, M.; Prasuhn, D.; von Rossen, P.; Scheid, H.; Schirm, N.; Schwandt, F.; Scobel, W.; Trelle, H. J.; Wellinghausen, A.; Wiedmann, W.; Woller, K.; Ziegler, R.
2006-01-01
The EDDA-detector at the cooler-synchrotron COSY/Jülich has been operated with an internal CH2 fiber target to measure proton-proton elastic scattering differential cross-sections. For data analysis knowledge of beam parameters, like position, width and angle, are indispensable. We have developed a method to obtain these values with high precision from the azimuthal and polar angles of the ejectiles only, by exploiting the coplanarity of the two final-state protons with the beam and the kinematic correlation. The formalism is described and results for beam parameters obtained during beam acceleration are given.
Energy Technology Data Exchange (ETDEWEB)
Golwala, Sunil Ramanlal [UC, Berkeley
2000-01-01
Extensive evidence indicates that a large fraction of the matter in the universe is nonluminous, nonbaryonic, and “cold” — nonrelativistic at the time matter began to dominate the energy density of the universe. Weakly Interacting Massive Particles (WIMPs) are an excellent candidate for nonbaryonic, cold dark matter. Minimal supersymmetry provides a natural WIMP candidate in the form of the lightest superpartner, with a typical mass Mδ ~ 100 GeV c-2 . WIMPs are expected to have collapsed into a roughly isothermal, spherical halo within which the visible portion of our galaxy resides. They would scatter off nuclei via the weak interaction, potentially allowingtheir direct detection. The Cryogenic Dark Matter Search (CDMS) employs Ge and Si detectors to search for WIMPs via their elastic-scatteringinteractions with nuclei while discriminatingagainst interactions of background particles. The former yield nuclear recoils while the latter produce electron recoils. The ionization yield (the ratio of ionization production to recoil energy in a semiconductor) of a particle interaction differs greatly for nuclear and electron recoils. CDMS detectors measure phonon and electron-hole-pair production to determine recoil energy and ionization yield for each event and thereby discriminate nuclear recoils from electron recoils. This dissertation reports new limits on the spin-independent WIMP-nucleon elastic-scattering cross section that exclude unexplored parameter space above 10 GeV c-2 WIMP mass and, at > 75% CL, the entire 3σ allowed region for the WIMP signal reported by the DAMA experiment. The experimental apparatus, detector performance, and data analysis are fully described.
An investigation into electron scattering from pyrazine at intermediate and high energies
Energy Technology Data Exchange (ETDEWEB)
Sanz, A. G.; Fuss, M. C. [Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, Serrano 113-bis, 28006 Madrid (Spain); Blanco, F. [Departamento de Física Atómica, Molecular y Nuclear, Universidad Complutense de Madrid, Ciudad Universitaria, 28040 Madrid (Spain); Gorfinkiel, J. D. [Department of Physical Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA (United Kingdom); Almeida, D.; Ferreira da Silva, F.; Limão-Vieira, P. [Laboratório de Colisões Atómicas e Moleculares, CEFITEC, Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Brunger, M. J. [ARC Centre for Antimatter-Matter Studies, School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, SA 5001 (Australia); Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia); García, G., E-mail: g.garcia@iff.csic.es [Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, Serrano 113-bis, 28006 Madrid (Spain); Centre for Medical Radiation Physics, University of Wollongong, NSW 2522 (Australia)
2013-11-14
Total electron scattering cross sections for pyrazine in the energy range 10–500 eV have been measured with a new magnetically confined electron transmission-beam apparatus. Theoretical differential and integral elastic, as well as integral inelastic, cross sections have been calculated by means of a screening-corrected form of the independent-atom representation (IAM-SCAR) from 10 to 1000 eV incident electron energies. The present experimental and theoretical total cross sections show a good level of agreement, to within 10%, in the overlapping energy range. Consistency of these results with previous calculations (i.e., the R-matrix and Schwinger Multichannel methods) and elastic scattering measurements at lower energies, below 10 eV, is also discussed.
Neutron elastic scattering on lead at 3.0 MeV
Energy Technology Data Exchange (ETDEWEB)
Chavez, E.; Huerta, A.; Ortiz, M.E.; Rodriguez, P.; Favela, F.; Marin, D. [lFUNAM, 04510 Mexico D.F. (Mexico); Moreno, E.; Murillo, G.; Policroniades, R.; Varela, A. [Laboratorio del Acelerador, INlN, AP 18-1027, Mexico D.F. (Mexico); Barron P, L. [Arizona State University, P.O. Box 871504 Tempe, AZ 85287-1504 (United States)
2007-12-15
Recent interest on precise information of the elastic scattering of fast (MeV) neutrons on {sup 208}Pb revealed the lack of sufficient experimental information. In this work we present new data obtained at the EN-Tandem Accelerator Laboratory of the 'Instituto Nacional de Investigaciones Nucleares' (ININ). A tagged mono-energetic flux of neutrons is generated through the D(d,n){sup 3}He reaction by detecting and identifying the conjugated Helium particles. The neutron 'cone' produced this way is directed towards a {sup nat}Pb target. The angular distribution of the scattered neutrons is measured between five and twenty degrees relative to the neutron direction by an array of plastic scintillators. Comparison with the previous data and optical model calculations is presented. Future perspectives are discussed. (Author)
A comparative study of processing simulated and experimental data in elastic laser light scattering.
Popovici, M A; Mincu, N; Popovici, A
1999-03-15
The intensity of the laser light scattered by a suspension of biological particles undergoing Brownian motion contains information about their size distribution function and optical properties. We used several methods (implemented in MathCAD programs), including a new one, to invert the Fredholm integral equation of the first kind, which represents the angular dependence of the elastic scattering of light. The algorithms were first tested on different sets of simulated data. Experimental data were obtained using biological samples and an experimental arrangement which are briefly described. We study the stability of the inversion procedures relative to the noise levels, and compute the first two moments of the retrieved size distribution function. A comparison of the results corresponding to simulated and experimental data is done, to select the best processing algorithm.
New high precision data on the differential cross sections of the pion-proton elastic scattering
Directory of Open Access Journals (Sweden)
Alekseev I. G.
2014-01-01
Full Text Available The EPECUR collaboration presents new high precision data on the pion-proton elastic scattering in the second resonance region. The experiment EPECUR is placed on the universal beam channel of the accelerator ITEP. The setup features 0.1% beam pion momentum tagging system, 25 cm long liquid hydrogen target, placed in mylar container and beryllium outer shell, low material wire drift chambers and high performance DAQ. More than 3 billions of triggers have been collected. The data cover pion beam momentum range 0.8 - 1.3 GeV/c and 40-120 degrees center-of-mass scattering angle range for both positive and negative pions. The measured differential cross section has 2% statistical accuracy in 2 degrees angle and 5 MeV/c momentum intervals.
Saito, Makina; Masuda, Ryo; Yoda, Yoshitaka; Seto, Makoto
2017-10-02
We developed a multi-line time-domain interferometry (TDI) system using 14.4 keV Mössbauer gamma rays with natural energy widths of 4.66 neV from 57Fe nuclei excited using synchrotron radiation. Electron density fluctuations can be detected at unique lengths ranging from 0.1 nm to a few nm on time scales from several nanoseconds to the sub-microsecond order by quasi-elastic gamma-ray scattering (QGS) experiments using multi-line TDI. In this report, we generalize the established expression for a time spectrum measured using an identical single-line gamma-ray emitter pair to the case of a nonidentical pair of multi-line gamma-ray emitters by considering the finite energy width of the incident synchrotron radiation. The expression obtained illustrates the unique characteristics of multi-line TDI systems, where the finite incident energy width and use of a nonidentical emitter pair produces further information on faster sub-picosecond-scale dynamics in addition to the nanosecond dynamics; this was demonstrated experimentally. A normalized intermediate scattering function was extracted from the spectrum and its relaxation form was determined for a relaxation time of the order of 1 μs, even for relatively large momentum transfer of ~31 nm-1. The multi-line TDI method produces a microscopic relaxation picture more rapidly and accurately than conventional single-line TDI.
Low-energy-electron scattering by CH3CN
Maioli, Leticia S.; Bettega, Márcio H. F.
2017-12-01
We report integral and differential cross sections for the elastic scattering of low-energy electrons by methyl cyanide (CH3CN), also known as acetonitrile. The cross sections were computed using the Schwinger multichannel method implemented with pseudopotentials. The fixed-nuclei scattering calculations were performed in the static-exchange and static-exchange plus polarization approximations for energies up to 15 eV. In our calculations with polarization effects, we found a π * shape resonance at around 2.22 eV and a broad structure associated to a σ * shape resonance at around 7 eV. The low-lying resonance was assigned to the electron capture by the two-fold degenerate π * orbital of the E symmetry of C 3 v group; the second was assigned to a σ * shape resonance in the A 1 symmetry. We compared our cross sections with theoretical results and experimental data available in the literature, and in general we found good agreement for the positions of the two resonances.
Precise determination of the spin-transfer coefficient KNN' for n->p elastic scattering at 187 MeV
Yang, Haichuan
IUCF experiment E401 determined the normal component spin-transfer coefficient KNN' for n->p elastic scattering at 187 MeV to an accuracy approaching ~+/-0.014 at 12 angles in the far-backward region (110° 14 obtained in earlier partial wave analyses or in fits to static few- body properties. Precise determination of np spin observables at intermediate energies may play an important role in resolving this discrepancy. The measurement was carried out at IUCF using the upgraded Polarized Neutron Facility (PNF). The polarized neutron beam was produced via the D(p->, n->) 2p reaction by bombarding a liquid deuterium target with polarized protons. After collimation, neutron fluxes of up to 5 × 106 n/s, with typical polarization Pn ~= 0.6, impinged on a solid CH2 target. Detection of both the proton and neutron from the second scattering, p(n->,p-> )n , provides event identification. Energy, angle, and timing information was collected for both outgoing nucleons on an event-by-event basis. An array of plastic scintillators comprised a neutron hodoscope, with angle segmentation of Δθ = +/-2° and Δφ = +/-2° in the lab frame. Effective n - γ discrimination was based on the correlation between neutron flight time and proton scattering angle. The forward-going protons were tracked with four planes each of vertical and horizontal drift chambers, and their polarization analyzed with a carbon-block polarimeter, containing two X-Y pairs of multi-wire proportional chambers and ΔE - E detectors (plastic scintillator), similar to that used on the IUCF K600 spectrometer. Free-scattering correlations, imposed in software, reduced quasi-free contributions to less than 1% of the measured yields. Results for KNN' are compared to predictions of several partial wave analyses and potential models. The implication of these data for the magnitude of g2c is examined.
Measuring the Weak Charge of the Proton via Elastic Electron-Proton Scattering
Energy Technology Data Exchange (ETDEWEB)
Jones, Donald C. [Univ. of Virginia, Charlottesville, VA (United States)
2015-10-01
The Qweak experiment which ran in Hall C at Jefferson Lab in Newport News, VA, and completed data taking in May 2012, measured the weak charge of the proton Q^{p}_{W} via elastic electron-proton scattering. Longitudinally polarized electrons were scattered from an unpolarized liquid hydrogen target. The helicity of the electron beam was flipped at approximately 1 kHz between left and right spin states. The Standard Model predicts a small parity-violating asymmetry of scattering rates between right and left helicity states due to the weak interaction. An initial result using 4% of the data was published in October 2013 [1] with a measured parity-violating asymmetry of -279 ± 35(stat) ± 31 (syst) ppb. This asymmetry, along with other data from parity-violating electron scattering experiments, provided the world's first determination of the weak charge of the proton. The weak charge of the proton was found to be ^{p}_{W} = 0.064 ± 0.012, in good agreement with the Standard Model prediction of ^{p}_{W}(SM) = 0.0708 ± 0.0003[2].
New effects in low energy scattering of p{mu} atoms
Energy Technology Data Exchange (ETDEWEB)
Wozniak, J. [Institute of Physics and Nuclear Techniques (Poland); Adamczak, A. [Institute of Nuclear Physics (Poland); Beer, G.A. [University of Victoria (Canada); Bystritsky, V.M. [Joint Institute for Nuclear Research (Russian Federation); Filipowicz, M. [Institute of Physics and Nuclear Techniques (Poland); Fujiwara, M.C. [University of British Columbia (Canada); Huber, T.M. [Gustavus Adolphus College (United States); Jacot-Guillarmod, R. [University of Fribourg (Switzerland); Kammel, P. [University of California (United States); Kim, S.K. [Jeonbuk National University (Korea, Republic of); Knowles, P.E. [University of Fribourg (Switzerland); Kunselman, A.R. [University of Wyoming (United States); Maier, M. [University of Victoria (Canada); Markushin, V.E. [Paul Scherrer Institute (Switzerland); Marshall, G.M. [TRIUMF (Canada); Mulhauser, F. [University of Fribourg (Switzerland); Olin, A. [University of Victoria (Canada); Petitjean, C. [Paul Scherrer Institute (Switzerland); Porcelli, T.A. [University of Victoria (Canada); Stolupin, V.A. [Joint Institute for Nuclear Research (Russian Federation)] (and others)
1999-06-15
Strong solid state effects in low energy scattering of p{mu} atoms in solid hydrogen are reported and analyzed. Such effects have been observed in TRIUMF experiment E742 where muons are stopped in thin frozen (3 K) layers of hydrogen. Emission of low energy p{mu} atoms from the hydrogen layer into adjacent vacuum was much higher than expected, based on calculations which ignored the solid nature of hydrogen. Monte Carlo simulations, performed using the scattering cross-sections with solid state effects taken into account, show the important role of the coherent elastic Bragg scattering in the diffusion of p{mu} atoms. For p{mu} energies lower than the Bragg cut-off limit ({approx}2 meV) the total scattering cross-section falls by several orders of magnitude, the hydrogen target becomes transparent and the emission of cold p{mu} atoms takes place.
Interaction of 1p nuclei: Case of 14N+12C Elastic Scattering at 21.0 MeV
Burtebayev, N.; Alimov, D.; Boztosun, I.; Burtebayeva, J.; Kerimkulov, Zh K.; Nassurlla, M.; Amangeldy, N.; Morzabayev, A. K.; Sakhiev, S. K.; Hamada, Sh
2015-04-01
Optical model analysis has been conducted for the elastic scattering of 1p-shell nuclei around the Coulomb barrier energies. We have used both microscopic double-folding and phenomenological potentials for the real part of the complex nuclear potential. The imaginary potential has the shape of phenomenological Wood-Saxon volume. The case 14N+12C for 1p-shell nuclei has been studied in detail and it is noticed that a large normalization of the strength of the double-folding real potential is needed to explain the structure observed in the experimental data. A good agreement between experimental data and theoretical results is obtained for the phenomenological potential case.
The Effect of Nuclear Elastic Scattering on Temperature Equilibration Rate of Ions in Fusion Plasma
Directory of Open Access Journals (Sweden)
M. Mahdavi
2014-01-01
Full Text Available A plasma with two different particle types and at different temperatures has been considered, so that each type of ion with Maxwell-Boltzmann distribution function is in temperature equilibrium with itself. Using the extracted nuclear elastic scattering differential cross-section from experimental data, solving the Boltzmann equation, and also taking into account the mobility of the background particles, temperature equilibration rate between two different ions in a fusion plasma is calculated. The results show that, at higher temperature differences, effect of nuclear elastic scattering is more important in calculating the temperature equilibration rate. The obtained expressions have general form so that they are applicable to each type of particle for background (b and each type for projectile (p. In this paper, for example, an equimolar Deuterium-Hydrogen plasma with density n=5×1025 cm−3 is chosen in which the deuteron is the background particle with temperature (also electron temperature Tb=1 keV (usual conditions for a fusion plasma at the ignition instant and the proton is the projectile with temperature Tp>Tb. These calculations, particularly, are very important for ion fast ignition in inertial confinement fusion concept.
Energy Technology Data Exchange (ETDEWEB)
Mourant, J.R.; Boyer, J.; Johnson, T.M.; Lacey, J.; Bigio, I.J. [Los Alamos National Lab., NM (United States); Bohorfoush, A. [Wisconsin Medical School, Milwaukee, WI (United States). Dept. of Gastroenterology; Mellow, M. [Univ. of Oklahoma Medical School, Oklahoma City, OK (United States). Dept. of Gastroenterology
1995-03-01
The Los Alamos National Laboratory has continued the development of the Optical Biopsy System (OBS) for noninvasive, real-time in situ diagnosis of tissue pathologies. In proceedings of earlier SPIE conferences we reported on clinical measurements in the bladder, and we report here on recent results of clinical tests in the gastrointestinal tract. With the OBS, tissue pathologies are detected/diagnosed using spectral measurements of the elastic optical transport properties (scattering and absorption) of the tissue over a wide range of wavelengths. The use of elastic scattering as the key to optical tissue diagnostics in the OBS is based on the fact that many tissue pathologies, including a majority of cancer forms, exhibit significant architectural changes at the cellular and sub-cellular level. Since the cellular components that cause elastic scattering have dimensions typically on the order of visible to near-IR wavelengths, the elastic (Mie) scattering properties will be wavelength dependent. Thus, morphology and size changes can be expected to cause significant changes m an optical signature that is derived from the wavelength-dependence of elastic scattering. Additionally, the optical geometry of the OBS beneficially enhances its sensitivity for measuring absorption bands. The OBS employs a small fiber-optic probe that is amenable to use with any endoscope or catheter, or to direct surface examination, as well as interstitial needle insertion. Data acquistion/display time is <1 second.
Energy Technology Data Exchange (ETDEWEB)
Dorman, Mark Edward [Univ. College London, Bloomsbury (United Kingdom)
2008-04-01
The Main Injector Neutrino Oscillation Search (MINOS) is a long baseline neutrino oscillation experiment based at the Fermi National Accelerator Laboratory (FNAL) in Chicago, Illinois. MINOS measures neutrino interactions in two large iron-scintillator tracking/sampling calorimeters; the Near Detector on-site at FNAL and the Far Detector located in the Soudan mine in northern Minnesota. The Near Detector has recorded a large number of neutrino interactions and this high statistics dataset can be used to make precision measurements of neutrino interaction cross sections. The cross section for charged-current quasi-elastic scattering has been measured by a number of previous experiments and these measurements disagree by up to 30%. A method to select a quasi-elastic enriched sample of neutrino interactions in the MINOS Near Detector is presented and a procedure to fit the kinematic distributions of this sample and extract the quasi-elastic cross section is introduced. The accuracy and robustness of the fitting procedure is studied using mock data and finally results from fits to the MINOS Near Detector data are presented.
Surface energy, elasticity and the homogenization of rough surfaces
Mohammadi, P.; Liu, L. P.; Sharma, P.; Kukta, R. V.
2013-02-01
The concept of surface energy is widely used to understand numerous aspects of material behavior: fracture, self-assembly, catalysis, void formation, microstructure evolution, and size-effect exhibited by nanostructures. Extensive work exists on deriving homogenized constitutive responses for macroscopic composites—relating effective properties to various microstructural details. In the present work, we focus on homogenization of surfaces. Indeed, elucidation of the effect of surface roughness on the surface energy, stress, and elastic behavior is relatively under-studied and quite relevant to the behavior of both nanostructures and bulk material where surfaces are involved in some form or fashion. We present derivations that relate both periodic and random roughness to the effective surface elastic behavior. We find that the residual surface stress is hardly affected by roughness while the superficial elastic properties are dramatically altered and, importantly, they may also change sign—this has significant ramifications in the interpretation of sensing based on frequency measurement changes. Interestingly, even if the bare surface has a zero surface elasticity modulus, roughness is seen to endow it with one. Using atomistic calculations, we verify the qualitative validity of the obtained theoretical insights. We show, through an illustrative example, that the square of resonance frequency of a cantilever beam with rough surface can decrease almost by a factor of two compared to a flat surface.
Energy Technology Data Exchange (ETDEWEB)
Beck, C. [Institut Pluridisciplinaire Hubert Curien, UMR 7178, IN2P3-CNRS et Universite Louis Pasteur (Strasbourg I), 23 rue du Loess - BP28, F-67037 Strasbourg Cedex 2 (France); Keeley, N. [DSM/DAPNIA/SPhN CEA Saclay, Orme des Merisiers, F-91191 Gif-sur-Yvette Cedex (France); Diaz-Torres, A. [Department of Nuclear Physics, Research School of Physical Sciences and Engineering, The Australian National University, Canberra ACT 0200 (Australia)
2007-03-15
The influence on fusion of coupling to the breakup process is investigated for reactions where at least one of the colliding nuclei has a sufficiently low binding energy for breakup to become an important process. Elastic scattering, excitation functions for sub-and near-barrier fusion cross sections, and breakup yields are analyzed for {sup 6,7}Li+{sup 59}Co. Continuum-Discretized Coupled-Channels (CDCC) calculations describe well the data at and above the barrier. Elastic scattering with {sup 6}Li (as compared to {sup 7}Li) indicates the significant role of breakup for weakly bound projectiles. A study of {sup 4,6}He induced fusion reactions with a three-body CDCC method for the {sup 6}He halo nucleus is presented. The relative importance of breakup and bound-state structure effects on total fusion is discussed. (authors)
Low Energy Electron Scattering from Fuels
Lopes, M. Cristina A.
2012-06-01
We report an investigation of processes that occur during the ignition of the plasma and its consequences in post-discharge time for an internal combustion engine, in order to find the appropriate parameters to be used in cars that operate with lean mixtures air-fuel. The relevance of this theme has attracted much attention, and has been one of the subjects of collaboration between experimental and theoretical groups in the USA and Brazil. We have produced some basic information necessary to modeling spark ignition in alcohol- fuelled engines. Total cross sections of electron scattering by methanol and ethanol molecules were obtained, using the linear transmission method based on the Beer-Lambert law to first approximation. Measurements and calculations of differential cross sections for low-energy (rotationally unresolved) electron scattering were also obtained, for scattering angles of 5 --130 . The measurements were taken using the relative flow method with an aperture source, and calculations using two different implementations of the Schwinger multichannel method, one that takes all electrons into account and is adapted for parallel computers, and another that uses pseudopotentials and considers only the valence electrons. Additionally to these, computer simulation studies of electronic discharge in mixtures of ethanol were performed, using a Zero-Dimensional Plasma Kinetic solver. Previous reported models for combustion of ethanol and cross sections data for momentum transfer of electron collisions with ethanol were used. The time evolutions of the main species densities are reported and the ignition time delay discussed.
Scattering of near-zero-energy electrons and positrons by H2
Zhang, J.-Y.
2014-04-15
The parameters for S-wave elastic scattering of near-zero-energy electrons and positrons by H2 molecules are calculated using the stabilization method with explicitly correlated Gaussians. The confined variational method is applied to optimize the Gaussians to describe the short-range interaction of incident e± with H2 in the fixed-nuclei approximation. For e+-H2 scattering the scattering length of previous work [Phys. Rev. Lett. 103, 223202 (2009)] is substantially improved. More importantly, for e−-H2 scattering, from first principles, the scattering length is computed as a function of the internuclear distance. In the case that the two nuclei are at the equilibrium distance the results are in a good agreement with values derived from fitting experimental total and diffusion cross sections to the modified effective range theory.
Integrated analysis of energy transfers in elastic-wave turbulence.
Yokoyama, Naoto; Takaoka, Masanori
2017-08-01
In elastic-wave turbulence, strong turbulence appears in small wave numbers while weak turbulence does in large wave numbers. Energy transfers in the coexistence of these turbulent states are numerically investigated in both the Fourier space and the real space. An analytical expression of a detailed energy balance reveals from which mode to which mode energy is transferred in the triad interaction. Stretching energy excited by external force is transferred nonlocally and intermittently to large wave numbers as the kinetic energy in the strong turbulence. In the weak turbulence, the resonant interactions according to the weak turbulence theory produce cascading net energy transfer to large wave numbers. Because the system's nonlinearity shows strong temporal intermittency, the energy transfers are investigated at active and moderate phases separately. The nonlocal interactions in the Fourier space are characterized by the intermittent bundles of fibrous structures in the real space.
Measurement of proton-proton elastic scattering and total cross-section at $\\sqrt{s}$ = 7 TeV
Antchev, G; Atanassov, I; Avati, V; Baechler, J; Berardi, V; Berretti, M; Bossini, E; Bozzo, M; Brogi, P; Brucken, E; Buzzo, A; Cafagna, F S; Calicchio, M; Catanesi, M G; Covault, C.; Csanad, M.; Csorgo, T.; Deile, M.; Eggert, K.; Eremin, V.; Ferretti, R.; Ferro, F.; Fiergolski, A.; Garcia, F.; Giani, S.; Greco, V.; Grzanka, L.; Heino, J.; Hilden, T.; Intonti, R.A.; Kaspar, J.; Kopal, J.; Kundrat, V.; Kurvinen, K.; Lami, S.; Latino, G.; Lauhakangas, R.; Leszko, T.; Lippmaa, E.; Lokajıcek, M.; Lo Vetere, M.; Macrı, M.; Maki, T.; Mercadante, A.; Minafra, N.; Minutoli, S.; Nemes, F.; Niewiadomski, H.; Oliveri, E.; Oljemark, F.; Orava, R.; Oriunno, M.; Osterberg, K.; Palazzi, P.; Prochazka, J.; Quinto, M.; Radermacher, E.; Radicioni, E.; Ravotti, F.; Robutti, E.; Rodrıguez, F.L.; Ropelewski, L.; Ruggiero, G.; Saarikko, H.; Santroni, A.; Scribano, A.; Smajek, J.; Snoeys, W.; Sziklai, J.; Taylor, C.; Turini, N.; Vacek, V.; Vıtek, M.; Welti, J.; Whitmore, J.
2013-01-01
At the LHC energy of $\\sqrt{s}$ = 7 TeV, under various beam and background conditions, luminosities, and Roman Pot positions, TOTEM has measured the differential cross-section for proton-proton elastic scattering as a function of the four-momentum transfer squared t. The results of the different analyses are in excellent agreement demonstrating no sizeable dependence on the beam conditions. Due to the very close approach of the Roman Pot detectors to the beam center ( around 5 $\\sigma$ beam) in a dedicated run with $\\beta$* = 90m, abs(t)-values down to 5 10**-3 GeV**2 were reached. The exponential slope of the differential elastic cross-section in this newly explored abs(t)-region remained unchanged and thus an exponential fit with only one constant B = (19.90+/-0.3)GeV-2 over the large abs(t)-range from 0.005 to 0.2GeV**2 describes the differential distribution well. The high precision of the measurement and the large fit range lead to an error on the slope parameter B which is remarkably small compared to p...
Analysis of a finite PML approximation to the three dimensional elastic wave scattering problem
Bramble, James H.
2010-01-01
We consider the application of a perfectly matched layer (PML) technique to approximate solutions to the elastic wave scattering problem in the frequency domain. The PML is viewed as a complex coordinate shift in spherical coordinates which leads to a variable complex coefficient equation for the displacement vector posed on an infinite domain (the complement of the scatterer). The rapid decay of the PML solution suggests truncation to a bounded domain with a convenient outer boundary condition and subsequent finite element approximation (for the truncated problem). We prove existence and uniqueness of the solutions to the infinite domain and truncated domain PML equations (provided that the truncated domain is sufficiently large). We also show exponential convergence of the solution of the truncated PML problem to the solution of the original scattering problem in the region of interest. We then analyze a Galerkin numerical approximation to the truncated PML problem and prove that it is well posed provided that the PML damping parameter and mesh size are small enough. Finally, computational results illustrating the efficiency of the finite element PML approximation are presented. © 2010 American Mathematical Society.
Energy trapping in power transmission through an elastic plate by finite piezoelectric transducers.
Yang, Zengtao; Yang, Jiashi; Hu, Yuantai
2008-11-01
We study transmission of electric energy through an elastic plate by acoustic wave propagation and piezoelectric transducers. Our mechanics model consists of an elastic plate with finite piezoelectric patches on both sides of the plate. A theoretical analysis using the equations of elasticity and piezoelectricity is performed. Energy trapping that describes the confinement and localization of the vibration energy is examined.
Elastic scattering of the halo nucleus 6 He from 197 Au at Elab=27 MeV
Directory of Open Access Journals (Sweden)
O. R. Kakuee
2003-12-01
Full Text Available A radioactive ion beam of 6He produced via the 7Li(p,2p6He reaction with typical intensity of 3 × 106 ions/see was elastically scattered from LiF(Au targets. Elastic scattering of 6He at Elab=27 MeV with 197Au have been measured in the angular range of 6º-72º in the laboratory system employing LEDA and LAMP detection system. Optical Model calculations have been used to fit the data .
Measurements of elastic scattering cross sections of carbon, iron and lead for 75 MeV Neutrons
Energy Technology Data Exchange (ETDEWEB)
Ibaraki, Masanobu; Baba, Mamoru; Nauchi, Yasushi; Miura, Takako; Hirasawa, Yoshitaka; Hirakawa, Naohiro [Department of Quantum Science and Energy Engineering, Tohoku University, Sendai, Miyagi (Japan); Nakashima, Hiroshi; Meigo, Shin-ichiro; Tanaka, Susumu
1999-03-01
We have performed the measurements of elastic scattering cross sections of carbon, iron and lead for 75 MeV neutrons using a {sup 7}Li(p, n) quasi-monoenergetic neutron source. Elastically scattered neutrons were measured with a time of flight method (TOF) using five liquid scintillation detectors. The data were obtained at 25 laboratory angles between 2.6deg and 53.0deg. The experimental data were compared with the neutron cross section libraries, systematics used in cascade/transport codes and optical model calculations. (author)
Terashima, S; Takeda, H; Ishikawa, T; Itoh, M; Kawabata, T; Murakami, T; Uchida, M; Yasuda, Y; Yosoi, M; Zenihiro, J; Yoshida, H P; Noro, T; Ishida, T; Asaji, S; Yonemura, T
2008-01-01
Cross sections and analyzing powers for proton elastic scattering from $^{116,118,120,122,124}$Sn at 295 MeV have been measured for a momentum transfer of up to about 3.5 fm$^{-1}$ to deduce systematic changes of the neutron density distribution. We tuned the relativistic Love-Franey interaction to explain the proton elastic scattering of a nucleus whose density distribution is well known. Then, we applied this interaction to deduce the neutron density distributions of tin isotopes. The result of our analysis shows the clear systematic behavior of a gradual increase in the neutron skin thickness of tin isotopes with mass number.
Energy Technology Data Exchange (ETDEWEB)
Thiolliere, N
2005-10-15
Molten Salt Reactor (MSR) based on Th/U cycle is one of the new generation concepts for nuclear energy production. A typical MSR is a graphite-moderated core with liquid fuel ({sup 7}LiF +ThF{sub 4} + UF{sub 4}). Many numerical studies based on Monte-Carlo codes are currently carried out but the validity of these numerical result relies on the precise knowledge of neutron cross sections used such as elastic scattering on carbon ({sigma}{sub C}), fluorine ({sigma}{sub F}) and lithium 7 ({sigma}{sub Li}). The goal of this work is to obtain {sigma}{sub C} and {sigma}{sub F} between 1 eV and 100 keV. Such measurements have been performed at the Laboratoire de Physique Subatomique et de Cosmologie (LPSC) de Grenoble on the experimental platform PEREN using slowing-down time spectrometers (C and CF{sub 2}) associated to a pulsed neutron generator (GENEPI). Capture rates are obtained for reference materials (Au, Ag, Mo and In) using YAP scintillator coupled to a photo-multiplier. Very precise simulations (MCNP code) of the experimental setup have been performed and comparison with experiments has led to the determination of {sigma}{sub C} and {sigma}{sub F} with accuracies of 1% and 2% respectively. These results show a small discrepancy to evaluated nuclear data file (ENDF). Measures of total cross-sections {sigma}{sub C} and {sigma}{sub F} at higher energy (200 - 600 keV) were also carried out at Centre des Etudes Nucleaires de Bordeaux using a transmission method. Mono-energetic neutrons were produced by protons accelerated by a Van de Graaff accelerator on a LiF target and transmitted neutrons are counted in a proportional hydrogen gaseous detector. Discrepancies of 5% and 9% for {sigma}{sub C} and {sigma}{sub F} respectively with ENDF have been shown. (author)
Greene, E. F.; Hall, R. B.; Mason, E. A.
1975-01-01
The energy threshold behavior of elastic rainbow scattering near the transition to orbiting is derived. Analysis of the energy dependence of the rainbow angle shows that the full range from high energies down to orbiting can be fitted with two parameters. Thus, measurements of the rainbow angle can give essentially only two pieces of information about the potential. For potentials of common shapes, such measurements are sensitive to regions of the potential just beyond the minimum and give information about the shape of the potential in this range. However, neither a minimum nor a point of inflection in the potential is necessary for rainbow scattering.
Towards a Precision Measurement of Parity-Violating e-p Elastic Scattering at Low Momentum Transfer
Energy Technology Data Exchange (ETDEWEB)
Pan, Jie [Univ. of Manitoba, Winnipeg (Canada)
2012-01-01
The goal of the Q-weak experiment is to make a measurement of the proton's weak charge Q_{W}^{p} = 1 - 4 sin^{2}(θ_{W2(θWenergy. The measurement may be used for a precision test of the Standard Model (SM) prediction on the running of sin2(θWenergy scale. The Q-weak experiment operates at Thomas Jefferson National Accelerator Facility (Jefferson Lab). The experiment determines QWp by measuring the parity violating asymmetry in elastic electron-proton scattering at low momentum transfer Q2 = 0.026 (GeV/c)2 and forward angles (8 degrees). The anticipated size of the asymmetry, based on the SM, is about 230 parts per billion (ppb). With the proposed accuracy, the experiment may probe new physics beyond Standard Model at the TeV scale. This thesis focuses on my contributions to the experiment, including track reconstruction for momentum transfer determination of the scattering process, and the focal plane scanner, a detector I designed and built to measure the flux profile of scattered electrons on the focal plane of the Q-weak spectrometer to assist in the extrapolation of low beam current tracking results to high beam current. Preliminary results from the commissioning and the first run period of the Q-weak experiment are reported and discussed.}
Haycraft, James J.
2009-12-01
The acoustic phonons of the epsilon polymorph of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazatetracyclo [5.5.0.05,9.03,11] dodecane (ɛ-CL-20) have been studied using Brillouin scattering spectroscopy. Analysis of the acoustic phonon velocities allowed determination of the complete stiffness tensor for this energetic material. The results are compared to a theoretical determination of the ɛ-CL-20 elastic constants, bulk moduli, and shear moduli. The observed ordering of elastic constants, C22>C33>C11, is noted to be different from other nitramine energetic materials. Finally, the elasticity of ɛ-CL-20 is compared to recently published reports on cyclotrimethylene trinitramine's (RDX) elasticity and the beta polymorph of cyclotetramethylene tetranitramine's (β-HMX) elasticity.
Elastic and inelastic scattering of {sup 15}N ions by {sup 9}Be at 84 MeV
Energy Technology Data Exchange (ETDEWEB)
Rudchik, A.T., E-mail: rudchik@kinr.kiev.ua [Institute for Nuclear Research, Ukrainian Academy of Sciences, Prospect Nauki 47, 03680 Kyiv (Ukraine); Chercas, K.A. [Institute for Nuclear Research, Ukrainian Academy of Sciences, Prospect Nauki 47, 03680 Kyiv (Ukraine); Kemper, K.W. [Physics Department, Florida State University, Tallahassee, FL 32306-4350 (United States); Rusek, K. [Heavy Ion Laboratory of Warsaw University, ul. L. Pasteura 5A, PL-02-093 Warsaw (Poland); Rudchik, A.A.; Herashchenko, O.V. [Institute for Nuclear Research, Ukrainian Academy of Sciences, Prospect Nauki 47, 03680 Kyiv (Ukraine); Koshchy, E.I. [Kharkiv National University, pl. Svobody 4, 61077 Kharkiv (Ukraine); Pirnak, Val.M. [Institute for Nuclear Research, Ukrainian Academy of Sciences, Prospect Nauki 47, 03680 Kyiv (Ukraine); Piasecki, E.; Trzcińska, A. [Heavy Ion Laboratory of Warsaw University, ul. L. Pasteura 5A, PL-02-093 Warsaw (Poland); Sakuta, S.B. [Russian Research Center “Kurchatov Institute”, Kurchatov Sq. 1, 123182 Moscow (Russian Federation); Siudak, R. [H. Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, PL-31-342 Cracow (Poland); Strojek, I. [National Center for Nuclear Researches, ul. Hoża 69, PL-00-681 Warsaw (Poland); Stolarz, A. [Heavy Ion Laboratory of Warsaw University, ul. L. Pasteura 5A, PL-02-093 Warsaw (Poland); Ilyin, A.P.; Ponkratenko, O.A.; Stepanenko, Yu.M.; Shyrma, Yu.O. [Institute for Nuclear Research, Ukrainian Academy of Sciences, Prospect Nauki 47, 03680 Kyiv (Ukraine); Szczurek, A. [H. Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, PL-31-342 Cracow (Poland); Uleshchenko, V.V. [Institute for Nuclear Research, Ukrainian Academy of Sciences, Prospect Nauki 47, 03680 Kyiv (Ukraine)
2016-03-15
Angular distributions of the {sup 9}Be + {sup 15}N elastic and inelastic scattering were measured at E{sub lab}({sup 15}N) = 84 MeV (E{sub c.m.} = 31.5 MeV) for the 0–6.76 MeV states of {sup 9}Be and 0–6.32 MeV states of {sup 15}N. The data were analyzed within the optical model and coupled-reaction-channels method. The elastic and inelastic scattering, spin reorientations of {sup 9}Be in ground and excited states and {sup 15}N in excited states as well as the most important one- and two-step transfer reactions were included in the channels-coupling scheme. The parameters of the {sup 9}Be + {sup 15}N optical potential of Woods–Saxon form as well as deformation parameters of these nuclei were deduced. The analysis showed that the {sup 9}Be + {sup 15}N pure potential elastic scattering dominates at the forward angles whereas the ground state spin reorientation of {sup 9}Be gives a major contribution to the elastic scattering cross sections at the large angles. Contributions from particle transfers are found to be negligible for the present scattering system.
Qu, W. W.; Zhang, G. L.; Terashima, S.; Guo, C. L.; Tanihata, I.; Le, X. Y.; Wang, T. F.; Zhang, X. H.; Sun, Z. Y.; Duan, L. M.; Hu, R. J.; Lu, C. G.; Ma, P.
2016-10-01
To obtain the angular distributions of 12C + 12C elastic scatterings with the incident energies of 200-400A MeV for the study of three-body forces, a detector system was constructed at second Radioactive Ion Beam Line in Lanzhou (RIBLL2) of Institute of Modern Physics (IMP). This system was composed of five plastic scintillation detectors with two read-outs for each detector, a Multi Wire Proportional Chamber (MWPC) and a 4×4 CsI(Tl) array. The 12C beam with the incident energy of 200A MeV on a natural carbon target was used to test this detector system. It is found that the plastic scintillation detector can give the good energy loss (Δ E) and time of flight (TOF) signals, it can also reflect the position information of scattered 12C events. MWPC can precisely provide the trajectories of scattered particles. This system has a very good particle identification ability and can clearly distinguish the scattered 12C particles from the fragments. It can be used for the study of the three-body forces effect for high energy heavy-ion scattering.
Energy Technology Data Exchange (ETDEWEB)
Abrahamyan, S; Afanasev, A; Ahmed, Z; Albataineh, H; Aniol, K; Armstrong, D S; Armstrong, W; Arrington, J; Averett, T; Babineau, B; Bailey, S L; Barber, J; Barbieri, A; Beck, A; Bellini, V; Beminiwattha, R; Benaoum, H; Benesch, J; Benmokhtar, F; Bertin, P; Bielarski, T; Boeglin, W; Bosted, P; Butaru, F; Burtin, E; Cahoon, J; Camsonne, A; Canan, M; Carter, P; Chang, C C; Cates, G D; Chao, Y -C; Chen, C; Chen, J -P; Choi, Seonho; Chudakov, E; Cisbani, E; Craver, B; Cusanno, F; Dalton, M M; De Leo, R; de Jager, K; Deconinck, W; Decowski, P; Deepa, D; Deng, X; Dutta, D; Etile, A; Ferdi, C; Feuerbach, J; Finn, J M; Flay, D; Franklin, G B; Friend, M; Frullani, S; Fuchey, E; Fuchs, S A; Fuoti, K; Garibaldi, F; Gasser, E; Gilman, R; Guisa, A; Glamazdin, A; Glesener, L E; Gomez, J; Gorchtein, M; Grames, J; Grimm, K; Gu, C; Hansen, O; Hansknecht, J; Hen, O; Higinbotham, D W; Holmes, R S; Holmstrom, T; Horowitz, C J; Hoskins, J; Huang, J; Humensky, T B; Hyde, C E; Ibrahim, H; Itard, F; Jen, C -M; Jensen, E; Jiang, X; Jin, G; Johnston, S; Katich, J; Kaufman, L J; Kelleher, A; Kliakhandler, K; King, P M; Kolarkar, A; Kowalski, S; Kuchina, E; Kumar, K S; Lagamba, L; Lambert, D; LaViolette, P; Leacock, J; Leckey IV, J; Lee, J H; LeRose, J J; Lhuillier, D; Lindgren, R; Liyanage, N; Lubinsky, N; Mammei, J; Mammoliti, F; Margaziotis, D J; Markowitz, P; Mazouz, M; McCormick, K; McCreary, A; McNulty, D; Meekins, D G; Mercado, L; Meziani, Z -E; Michaels, R W; Mihovilovic, M; Moffit, B; Monaghan, P; Muangma, N; Munoz-Camacho, C; Nanda, S; Nelyubin, V; Neyret, D; Nuruzzaman,; Oh, Y; Otis, K; Palmer, A; Parno, D; Paschke, K D; Phillips, S K; Poelker, M; Pomatsalyuk, R; Posik, M; Potokar, M; Prok, K; Puckett, A.J.R.; Qian, X; Qiang, Y; Quinn, B; Rakhman, A; Reimer, P E; Reitz, B; Riordan, S; Roche, J; Rogan, P; Ron, G; Russo, G; Saenboonruang, K; Saha, A; Sawatzky, B; Shahinyan, A; Silwal, R; Singh, J; Sirca, S; Slifer, K; Snyder, R; Solvignon, P; Souder, P A; Sperduto, M L; Subedi, R; Stutzman, M L; Suleiman, R; Sulkosky, V; Sutera, C M; Tobias, W A; Troth, W; Urciuoli, G M; Ulmer, P; Vacheret, A; Voutier, A; Waidyawansa, B; Wang, D; Wang, K; Wexler, J; Whitbeck, A; Wilson, R; Wojtsekhowski, B; Yan, X; Yao, H; Ye, Y; Ye, Z; Yim, V; Zana, L; Zhan, X; Zhang, J; Zhang, Y; Zheng, X; Ziskin, V; Zhu, P
2012-11-05
Here we have measured the beam-normal single-spin asymmetry A{sub n} in the elastic scattering of 1-3 GeV transversely polarized electrons from ^{1}H and for the first time from ^{4}He, ^{12}C, and ^{208}Pb. For ^{1}H, ^{4}He and ^{12}C, the measurements are in agreement with calculations that relate A_{n} to the imaginary part of the two-photon exchange amplitude including inelastic intermediate states. Surprisingly, the ^{208}Pb result is significantly smaller than the corresponding prediction using the same formalism. Our results suggest that a systematic set of new A^{n} measurements might emerge as a new and sensitive probe of the structure of heavy nuclei.
The G0 experiment: Parity violation in e-N elastic scattering
Energy Technology Data Exchange (ETDEWEB)
Philip G. Roos
2005-02-01
The G0 experiment will measure the parity-violating asymmetries in elastic electron-nucleon scattering. The experiment is being performed in Hall C at the Jefferson Laboratory using a polarized electron beam and a dedicated experimental setup. Measurements of the electron-proton asymmetries will be made at both forward and backward angles, and electron-deuteron asymmetries at the backward angles. These measurements will cover a momentum transfer range of 0.1 – 1.0 GeV2/c2. From these data the vector neutral weak form factors, GEZ and GMZ, and the effective axial current of the nucleon, GAe, may be extracted. When combined with the known electromagnetic form factors, one will be able to extract the contributions of u, d, and s quarks to the protons charge and magnetization distributions. The first measurements at forward angles for the full momentum transfer range have very recently been successfully completed and preliminary results are presented here.
mQfit, a new program for analyzing quasi-elastic neutron scattering data
Directory of Open Access Journals (Sweden)
Martinez Nicolas
2015-01-01
Full Text Available Analysis of Quasi-elastic Neutron Scattering (QENS data of complex systems such as biological or soft matter samples in a comprehensive and explicit way often requires great efforts. Most popular software only allows to fit spectra originating from one single instrument and does not permit to extract parameters from a model that is fitted simultaneously to data taken at different instrumental resolutions. We present here a new program, mQfit (multiple QENS dataset fitting, that enables to fit QENS data taken at different spectrometers (with typical resolutions between 0.01 and 0.1 meV and momentum transfer ranges. This allows drastically reducing the number of fitting parameters. The routine is implemented with a user friendly Graphical User's Interface (GUI, and freely available. As an example, we will present results obtained on E. coli bacterial pellets, and compare them to values published in the literature.
Energy Technology Data Exchange (ETDEWEB)
Khurgin, Jacob B., E-mail: jakek@jhu.edu [Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Bajaj, Sanyam; Rajan, Siddharth [Department of Electrical and Computer Engineering, The Ohio State University, Columbus, Ohio 43210 (United States)
2015-12-28
Longitudinal optical (LO) phonons in GaN generated in the channel of high electron mobility transistors (HEMT) are shown to undergo nearly elastic scattering via collisions with hot electrons. The net result of these collisions is the diffusion of LO phonons in the Brillouin zone causing reduction of phonon and electron temperatures. This previously unexplored diffusion mechanism explicates how an increase in electron density causes reduction of the apparent lifetime of LO phonons, obtained from the time resolved Raman studies and microwave noise measurements, while the actual decay rate of the LO phonons remains unaffected by the carrier density. Therefore, the saturation velocity in GaN HEMT steadily declines with increased carrier density, in a qualitative agreement with experimental results.
An accurate boundary element method for the exterior elastic scattering problem in two dimensions
Bao, Gang; Xu, Liwei; Yin, Tao
2017-11-01
This paper is concerned with a Galerkin boundary element method solving the two dimensional exterior elastic wave scattering problem. The original problem is first reduced to the so-called Burton-Miller [1] boundary integral formulation, and essential mathematical features of its variational form are discussed. In numerical implementations, a newly-derived and analytically accurate regularization formula [2] is employed for the numerical evaluation of hyper-singular boundary integral operator. A new computational approach is employed based on the series expansions of Hankel functions for the computation of weakly-singular boundary integral operators during the reduction of corresponding Galerkin equations into a discrete linear system. The effectiveness of proposed numerical methods is demonstrated using several numerical examples.
Energy Technology Data Exchange (ETDEWEB)
Aoun, Bachir; Pellegrini, Eric; Trapp, Marcus; Natali, Francesca; Cantù, Laura; Brocca, Paola; Gerelli, Yuri; Demé, Bruno; Marek Koza, Michael; Johnson, Mark; Peters, Judith
2016-04-01
Neutron scattering techniques have been employed to investigate 1,2-dimyristoyl-sn-glycero-3- phosphocholine (DMPC) membranes in the form of multilamellar vesicles (MLVs) and deposited, stacked multilamellar-bilayers (MLBs), covering transitions from the gel to the liquid phase. Neutron diffraction was used to characterise the samples in terms of transition temperatures, whereas elastic incoherent neutron scattering (EINS) demonstrates that the dynamics on the sub-macromolecular length-scale and pico- to nano-second time-scale are correlated with the structural transitions through a discontinuity in the observed elastic intensities and the derived mean square displacements. Molecular dynamics simulations have been performed in parallel focussing on the length-, time- and temperature-scales of the neutron experiments. They correctly reproduce the structural features of the main gel-liquid phase transition. Particular emphasis is placed on the dynamical amplitudes derived from experiment and simulations. Two methods are used to analyse the experimental data and mean square displacements. They agree within a factor of 2 irrespective of the probed time-scale, i.e. the instrument utilized. Mean square displacements computed from simulations show a comparable level of agreement with the experimental values, albeit, the best match with the two methods varies for the two instruments. Consequently, experiments and simulations together give a consistent picture of the structural and dynamical aspects of the main lipid transition and provide a basis for future, theoretical modelling of dynamics and phase behaviour in membranes. The need for more detailed analytical models is pointed out by the remaining variation of the dynamical amplitudes derived in two different ways from experiments on the one hand and simulations on the other.
A Quasi-Elastic Neutron Scattering Study of the Dynamics of Electrically Constrained Water.
Fuchs, Elmar C; Bitschnau, Brigitte; Wexler, Adam D; Woisetschläger, Jakob; Freund, Friedemann T
2015-12-31
We have measured the quasi-elastic neutron scattering (QENS) of an electrohydrodynamic liquid bridge formed between two beakers of pure water when a high voltage is applied, a setup allowing to investigate water under high-voltage without high currents. From this experiment two proton populations were distinguished: one consisting of protons strongly bound to oxygen atoms (immobile population, elastic component) and a second one of quasi-free protons (mobile population, inelastic component) both detected by QENS. The diffusion coefficient of the quasi-free protons was found to be D = (26 ± 10) × 10(-5) cm(2) s(-1) with a jump length lav ∼ 3 Å and an average residence time of τ0 = 0.55 ± 0.08 ps. The associated proton mobility in the proton channel of the bridge is ∼9.34 × 10(-7) m(2) V(-1) s(-1), twice as fast as diffusion-based proton mobility in bulk water. It also matches the so-called electrohydrodynamic or "apparent" charge mobility, an experimental quantity which so far has lacked molecular interpretation. These results further corroborate the proton channel model for liquid water under high voltage and give new insights into the molecular mechanisms behind electrohydrodynamic charge transport phenomena and delocalization of protons in liquid water.
High energy gravitational scattering: a numerical study
Marchesini, Giuseppe
2008-01-01
The S-matrix in gravitational high energy scattering is computed from the region of large impact parameters b down to the regime where classical gravitational collapse is expected to occur. By solving the equation of an effective action introduced by Amati, Ciafaloni and Veneziano we find that the perturbative expansion around the leading eikonal result diverges at a critical value signalling the onset of a new regime. We then discuss the main features of our explicitly unitary S-matrix down to the Schwarzschild's radius R=2G s^(1/2), where it diverges at a critical value b ~ 2.22 R of the impact parameter. The nature of the singularity is studied with particular attention to the scaling behaviour of various observables at the transition. The numerical approach is validated by reproducing the known exact solution in the axially symmetric case to high accuracy.
Energy Technology Data Exchange (ETDEWEB)
Kreutzfeldt, Kristof
2014-12-15
The ATLAS experiment with the ALFA sub-detector, provides a unique opportunity to measure elastic proton-proton scattering at the LHC at a centre-of-mass energy of √(s)=7 TeV, that has never been reached before. The ALFA detector is a tracking detector housed in Roman Pots, which makes it possible to measure elastically scattered protons down to very small scattering angles. From the proton tracks, measured during a LHC fill with special β{sup *}=90 m beam optics, the differential elastic cross-section as a function of the four-momentum transfer squared t is determined, and the total hadronic cross-section σ{sub tot}, the nuclear slope parameter B and further derived quantities are extracted by utilizing the optical theorem. The total hadronic cross-section is a fundamental parameter of strong interaction depending on the centre-of-mass energy. It has been measured for more than 50 years at different energies and accelerators, where a rise with energy was observed. A newly developed fully data-driven method is used to determine the t-independent event reconstruction efficiency in the two spectrometer arms to be ε{sub rec}(Arm 1368)=0.8974±0.0005(stat.)±0.0061(syst.) and ε{sub rec}(Arm 2457)=0.8800±0.0005(stat.)±0.0092(syst.) by carefully selecting elastic-scattering events not reconstructed in the entire ALFA detector. Special care is also taken of other important aspects of the analysis like the determination of the luminosity and beam optics parameters. An integrated luminosity of L=80 μb{sup -1} is accumulated to measure the differential elastic cross-section from which the total hadronic cross-section is extracted from a fit in the range 0.01 GeV{sup 2}≤-t≤0.1 GeV{sup 2} to be σ{sub tot}=95.35±0.38(stat.)±1.25(exp.)±0.37(extr.) mb. In addition, the nuclear slope parameter at small vertical stroke t vertical stroke is determined to be B=19.73±0.14(stat.)±0.26(syst.) GeV{sup -2}.
Narrow alpha+ sup 2 sup 8 Si elastic-scattering states at high excitation in sup 3 sup 2 S
Kaellman, K M; Lönnroth, T; Manngaard, P; Goldberg, V Z; Pakhomov, A E; Pankratov, V V
2003-01-01
The excitation function and angular distributions of elastic alpha-particle scattering on sup 2 sup 8 Si have been measured in the laboratory energy range 6-28 MeV using a backscattering technique on a thick target, yielding a continuous energy distribution. More than 200 narrow states are observed, with widths in the range propor to 30-100 keV at excitation energies E sup * =13-32 MeV. Angular distributions at backward angles were measured, and angular momentum values of more than 83 states have been deduced. The analysis gives spin-parities J suppi, alpha-partial widths GAMMA subalpha and reduced widths of the narrow high-lying resonant states in sup 3 sup 2 S. The experimentally observed states display both the negative- and the positive-parity rotational-like sequences with seemingly no parity splitting, a finding which is at variance with most potential-model predictions. The deduced effective moment of inertia indicates a more extended structure than the ground-state configuration. The observed strength...
Evaluation of anemia diagnosis based on elastic light scattering (Conference Presentation)
Tong, Lieshu; Wang, Xinrui; Xie, Dengling; Chen, Xiaoya; Chu, Kaiqin; Dou, Hu; Smith, Zachary J.
2017-03-01
Currently, one-third of humanity is still suffering from anemia. In China the most common forms of anemia are iron deficiency and Thalassemia minor. Differentiating these two is the key to effective treatment. Iron deficiency is caused by malnutrition and can be cured by iron supplementation. Thalassemia is a hereditary disease in which the hemoglobin β chain is lowered or absent. Iron therapy is not effective, and there is evidence that iron therapy may be harmful to patients with Thalassemia. Both anemias can be diagnosed using red blood cell morphology: Iron deficiency presents a smaller mean cell volume compared to normal cells, but with a wide distribution; Thalassemia, meanwhile, presents a very small cell size and tight particle size distribution. Several researchers have proposed diagnostic indices based on red cell morphology to differentiate these two diseases. However, these indices lack sensitivity and specificity and are constructed without statistical rigor. Using multivariate methods we demonstrate a new classification method based on red cell morphology that diagnoses anemia in a Chinese population with enough accuracy for its use as a screening method. We further demonstrate a low cost instrument that precisely measures red cell morphology using elastic light scattering. This instrument is combined with an automated analysis program that processes scattering data to report red cell morphology without the need for user intervention. Despite using consumer-grade components, when comparing our experimental results with gold-standard measurements, the device can still achieve the high precision required for sensing clinically significant changes in red cell morphology.
Near-Field Acoustic Resonance Scattering of a Finite Bessel Beam by an Elastic Sphere
Mitri, F G
2014-01-01
The near-field acoustic scattering from a sphere centered on the axis of a finite Bessel acoustic beam is derived stemming from the Rayleigh-Sommerfeld diffraction surface integral and the addition theorems for the spherical wave and Legendre functions. The beam emerges from a finite circular disk vibrating according to one of its radial modes corresponding to the fundamental solution of a Bessel beam J0. The incident pressure field's expression is derived analytically as a partial-wave series expansion taking into account the finite size and the distance from the center of the disk transducer. Initially, the scattered pressure by a rigid sphere is evaluated, and backscattering pressure moduli plots as well as 3-D directivity patterns for an elastic PMMA sphere centered on a finite Bessel beam with appropriate tuning of its half-cone angle, reveal possible resonance suppression of the sphere only in the zone near the Bessel transducer. Moreover, the analysis is extended to derive the mean spatial incident and...
Scanning elastic scattering spectroscopy detects metastatic breast cancer in sentinel lymph nodes
Austwick, Martin R.; Clark, Benjamin; Mosse, Charles A.; Johnson, Kristie; Chicken, D. Wayne; Somasundaram, Santosh K.; Calabro, Katherine W.; Zhu, Ying; Falzon, Mary; Kocjan, Gabrijela; Fearn, Tom; Bown, Stephen G.; Bigio, Irving J.; Keshtgar, Mohammed R. S.
2010-07-01
A novel method for rapidly detecting metastatic breast cancer within excised sentinel lymph node(s) of the axilla is presented. Elastic scattering spectroscopy (ESS) is a point-contact technique that collects broadband optical spectra sensitive to absorption and scattering within the tissue. A statistical discrimination algorithm was generated from a training set of nearly 3000 clinical spectra and used to test clinical spectra collected from an independent set of nodes. Freshly excised nodes were bivalved and mounted under a fiber-optic plate. Stepper motors raster-scanned a fiber-optic probe over the plate to interrogate the node's cut surface, creating a 20×20 grid of spectra. These spectra were analyzed to create a map of cancer risk across the node surface. Rules were developed to convert these maps to a prediction for the presence of cancer in the node. Using these analyses, a leave-one-out cross-validation to optimize discrimination parameters on 128 scanned nodes gave a sensitivity of 69% for detection of clinically relevant metastases (71% for macrometastases) and a specificity of 96%, comparable to literature results for touch imprint cytology, a standard technique for intraoperative diagnosis. ESS has the advantage of not requiring a pathologist to review the tissue sample.
Frehner, Marcel; Schmalholz, Stefan M.; Saenger, Erik H.; Steeb, Holger Karl
2008-01-01
Two-dimensional scattering of elastic waves in a medium containing a circular heterogeneity is investigated with an analytical solution and numerical wave propagation simulations. Different combinations of finite difference methods (FDM) and finite element methods (FEM) are used to numerically solve
Measurement of coherent elastic and inelastic deuteron-proton scattering at s = 2800 GeV$^{2}$
Armitage, J C; Bobbink, Gerjan J; Erné, F C; Kooijman, P M; Loebinger, F K; MacBeth, A A; Montgomery, H E; Murphy, P G; Poorthuis, J J M; Rudge, A; Sens, Johannes C; Stork, D H; Timmer, J
1978-01-01
Data on coherent elastic and inelastic deuteron-proton scattering are presented. The measurements were made at the CERN ISR with a single arm spectrometer, at s=2800 GeV/sup 2/ and momentum transfer squared (-t) in the range 0.15 to 0.42 GeV/sup 2/. The data are compared with elastic and inelastic proton-proton scattering data taken with the same apparatus at the same s and t values. The t dependence of the elastic dp to dp differential cross section is compared with simple predictions based on Glauber theory. The differential cross sections for pp to pX and dp to dX are also compared for M/sub X//sup 2/ to 280 GeV/sup 2/, where M/sub X/ denotes the mass of system X recoiling against the measured proton and deuteron. (25 refs).
Energy Technology Data Exchange (ETDEWEB)
Ravel, Olivier [Ecole Doctorale des Science Fondamentales, Universite Blaise Pascal, U.F.R. de Recherche Scientifique et Technique, F-63177 Aubiere Cedex (France)
1997-11-21
This thesis describes the electron beam energy measurement device at TJNAF hall A (Virginia USA). The accuracy of the measurement is 10{sup -4}. Such an accuracy is needed for scattering electron experiments, in particular for the determination of cross section by transverse-longitudinal separation. The method is based on the measurements of the scattering particle angles of the reaction p(e,e`p). Angular measurements are realized by a setup of silicon micro-strips detectors with an angular accuracy of 10{mu}rd. Theoretical aspects of the method and some techniques of electron beam energy measurement are presented. A precise uncertainty calculation allowed to determine the EP detector characteristics: thin target of polypropylene, silicon strips detectors, data acquisition, electronics and trigger. The high level of accuracy leads to the development of a new and original techniques of position measurement. The data analysis method, the beam energy calculation and the different corrections (vertex, radiative tails) are presented. The first tests of the detector are reviewed. The first measurement of TJNAF electron beam energy with the EP detector is foreseen on March 1998. (author) 43 refs., 84 figs., 32 tabs.
Susuki, Y
1975-01-01
The differential cross section of p-p elastic scattering in the CERN- ISR energy region has a marked diffraction-like dip at -t approximately 1.4 (GeV/c)/sup 2/. pi -N scattering has the dip-bump structure at low energies, but this feature fades as the energy goes higher, consistently with its non-Pomeron Regge-pole interpretation. At higher energies the Pomeron will dominate the scattering at small momentum transfer and the observed dip in p-p scattering is expected to be closely related with the nature of the Pomeron. Therefore, the authors examine whether or not pi -N scattering shows the dip at small momentum transfer, say, -t<5 (GeV/c)/sup 2/ in the FNAL region. (9 refs).
Sekiguchi, K; Sakai, H; Witala, H; Ermisch, K; Glockle, W; Golak, J; Hatano, M; Kamada, H; Kalantar-Nayestanaki, N; Kato, H; Maeda, Y; Nishikawa, J; Nogga, A; Ohnishi, T; Okamura, H; Saito, T; Sakamoto, N; Sakoda, S; Satou, Y; Suda, K; Tamii, A; Uchigashima, T; Uesaka, T; Wakasa, T; Yako, K
The deuteron-to-proton polarization-transfer coefficients for d-p elastic scattering were precisely measured with an incoming deuteron energy of 135 MeV/nucleon at the RIKEN Accelerator Research Facility. The data are compared to theoretical predictions based on exact solution's of the three-nucleon
Measurement of Muon Neutrino Quasi-Elastic Scattering on a Hydrocarbon Target at E_{\
Fiorentini, G A; Rodrigues, P A; Aliaga, L; Altinok, O; Bodek, A; Boehnlein, D; Bradford, R; Brooks, W K; Budd, H; Butkevich, A; Caicedo, D A M; Castromonte, C M; Christy, M E; Chvojka, J; da Motta, H; Damiani, D S; Danko, I; Datta, M; Day, M; DeMaat, R; Devan, J; Diaz, G A; Dytman, S A; Eberly, B; Edmondson, D A; Felix, J; Fields, L; Fitzpatrick, T; Gago, A M; Gallagher, H; Gobbi, B; Gran, R; Harris, D A; Higuera, A; Howley, I J; Hurtado, K; Jerkins, M; Kafka, T; Kanter, M O; Keppel, C; Kordosky, M; Krajeski, A H; Kulagin, S A; Le, T; Leister, A G; Maggi, G; Maher, E; Manly, S; Mann, W A; Marshall, C M; McFarland, K S; McGivern, C L; McGowan, A M; Mislivec, A; Morfin, J G; Mousseau, J; Naples, D; Nelson, J K; Niculescu, G; Niculescu, I; Ochoa, N; O'Connor, C D; Osta, J; Palomino, J L; Paolone, V; Park, J; Patrick, C E; Perdue, G N; Pena, C; Rakotondravohitra, L; Ransome, R D; Ray, H; Ren, L; Sassin, K E; Schellman, H; Schneider, R M; Schulte, E C; Sedita, P; Simon, C; Snider, F D; Snyder, M C; Sobczyk, J T; Salinas, C J Solano; Tagg, N; Tan, W; Tice, B G; Tzanakos, G; Velasquez, J P; Walding, J; Walton, T; Wolcott, J; Wolthuis, B A; Zavala, G; Zhang, D; Ziemer, B P
2013-01-01
We report a study of muon neutrino charged-current quasi-elastic events in the segmented scintillator inner tracker of the MINERvA experiment running in the NuMI neutrino beam at Fermilab. The events were selected by requiring a {\\mu}^- and low calorimetric recoil energy separated from the interaction vertex. We measure the flux-averaged differential cross-section, d{\\sigma}/dQ^2, and study the low energy particle content of the final state. Deviations are found between the measured d{\\sigma}/dQ^2 and the expectations of a model of independent nucleons in a relativistic Fermi gas. We also observe an excess of energy near the vertex consistent with multiple protons in the final state.
Frictional and elastic energy in gecko adhesive detachment.
Gravish, Nick; Wilkinson, Matt; Autumn, Kellar
2008-03-06
Geckos use millions of adhesive setae on their toes to climb vertical surfaces at speeds of over 1 m s(-1). Climbing presents a significant challenge for an adhesive since it requires both strong attachment and easy, rapid removal. Conventional pressure-sensitive adhesives are either strong and difficult to remove (e.g. duct tape) or weak and easy to remove (e.g. sticky notes). We discovered that the energy required to detach adhering tokay gecko setae (W(d)) is modulated by the angle (theta) of a linear path of detachment. Gecko setae resist detachment when dragged towards the animal during detachment (theta = 30 degrees ) requiring W(d) = 5.0+/-0.86(s.e.) J m(-2) to detach, largely due to frictional losses. This external frictional loss is analogous to viscous internal frictional losses during detachment of pressure-sensitive adhesives. We found that, remarkably, setae possess a built-in release mechanism. Setae acted as springs when loaded in tension during attachment and returned elastic energy when detached along the optimal path (theta=130 degrees ), resulting in W(d) = -0.8+/-0.12 J m(-2). The release of elastic energy from the setal shaft probably causes spontaneous release, suggesting that curved shafts may enable easy detachment in natural, and synthetic, gecko adhesives.
Elastic and inelastic scattering of {sup 14}N ions by {sup 7}Li at 80 MeV (c.m. 26.7 MeV)
Energy Technology Data Exchange (ETDEWEB)
Rudchik, A.T.; Herashchenko, O.V.; Rudchik, A.A.; Mezhevych, S.Yu.; Mokhnach, A.V.; Pirnak, V.M.; Ponkratenko, O.A.; Ilyin, A.P.; Uleshchenko, V.V. [Institute for Nuclear Research, Kyiv (Ukraine); Kemper, K.W. [Florida State University, Physics Department, Tallahassee, Florida (United States); Rusek, K. [National Institute for Nuclear Research, Warsaw (Poland); Heavy Ion Laboratory of Warsaw University, Warsaw (Poland); Koshchy, E.I. [Kharkiv National University, Kharkiv (Ukraine); Kliczewski, S.; Siudak, R.; Szczurek, A. [H. Niewodniczanski Institute of Nuclear Physics, Cracow (Poland); Plujko, V.A. [Taras Shevchenko Kyiv National University, Kyiv (Ukraine); Choinski, J. [Heavy Ion Laboratory of Warsaw University, Warsaw (Poland); Stolarz, A. [National Institute for Nuclear Research, Warsaw (Poland)
2014-10-15
New angular distribution data for {sup 7}Li + {sup 14}N elastic and inelastic scattering at the energy E{sub lab} ({sup 14}N) = 80 MeV (c.m. 26.7MeV) are presented. The data were analyzed within the optical model and the coupled-reaction-channels method using a channels-coupling scheme that included the {sup 7}Li and {sup 14}N inelastic scattering channels, spin reorientations of {sup 7}Li and {sup 14}N as well as most important transfer reactions. The low-energy excited states of {sup 7}Li and {sup 14}N were assumed to be collective in nature. The {sup 7}Li + {sup 14}N potential parameters as well as deformation parameters of {sup 7}Li and {sup 14}N were deduced. The {sup 7}Li + {sup 14}N potential and the data were compared with those of {sup 6}Li + {sup 14}N to observe isotopic differences. The enhanced large-angle elastic and inelastic scattering data are shown to have a large contribution from the ground-state reorientation of {sup 7}Li. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Ibraeva, E. T., E-mail: ibraeva.elena@gmail.com [National Nuclear Center of Republic of Kazakhstan, Institute of Nuclear Physics (Kazakhstan); Imambekov, O. [Al-Farabi Kazakh National University (Kazakhstan)
2015-07-15
Differential cross sections for elastic p{sup 6,8}He and p{sup 8,9}Li scattering at energies between 60 and 70 MeV per nucleon and at the energy of 700 MeV per nucleon were calculated. The calculations in question were performed with the wave functions found on the basis of the α–n–n (for {sup 6}He), α–t–n (for {sup 8}Li), and α–t–2n (for {sup 9}Li) three-body models and with the density from the large-scale shell model for the {sup 8}He nucleus. The respective matrix elements were derived either upon taking fully into account the multiple-scattering operator or in the optical-limit approximation. A comparison of the results of the precise and approximate calculations made it possible to estimate reliably the contribution of higher multiplicity collisions to the differential cross sections.
A simple nonbinary scattering model applicable to atomic collisions is crystals at 1ow energies
DEFF Research Database (Denmark)
Andersen, Hans Henrik; Sigmund, Peter
1966-01-01
the projectile and each ring atom is described by a Born-Mayer potential, and the scattering is assumed to be elastic and governed by the classical equations of motion. Because of symmetry, the problem can be reduced to plane motion of a particle in a potential of elliptic symmetry. The elliptic force field...... the elliptic to the spherical potential are investigated. Special attention is paid to proper definitions of collision time and collision length which are important in collisions in crystals. Limitations to classical scattering arising from the uncertainty principle prove to be more serious than assumed...... previously. Inelastic contributions to the energy loss can easily be included. The oscillator forces binding lattice atoms turn out to influence the scattering process only at very small energies. The validity of the so-called momentum approximation and a related perturbation method are also investigated....
Li, Yueqiu; Wei, Peijun
2018-01-01
The reflection and transmission of thermal elastic waves at the interface between two different dipolar gradient elastic solids are studied based on the generalized thermo-elastic theory of Green and Naghdi [(1993). J. Elasticity 31, 189-208] (type II of no energy dissipation). First, some thermodynamic formulas are generalized to a dipolar gradient elastic solid and the function of free energy density is postulated. Second, equations of thermal motion and constitutive relations in a dipolar gradient elasticity are derived. Then the nontraditional interfacial conditions are used to determine the amplitude ratio of the reflection and transmission waves with respect to the incident wave. Some numerical results of the reflection and transmission coefficients in the form of an energy flux ratio are given for different microstructure parameters while thermal parameters are fixed. The numerical results are validated by the consideration of energy conservation. It is found that there are a total of five modes of dispersive waves, namely, coupled MT1 wave, coupled MT2 wave, coupled MT3 wave, SV wave, and one evanescent wave which reduces to the surface waves at an interface, namely, SS wave. The thermal parameters mainly affect the coupled MT2 wave while the microstructure parameters affect not only the coupled waves but also the SS surface waves.
Elastic and Inelastic Neutron Scattering with a C7LYC Array
Wilson, G. L.; Brown, T.; Chowdhury, P.; Doucet, E.; Lister, C. J.; D'Olympia, N.; Devlin, M.; Mosby, S.
2015-10-01
A scintillator array of 16 1'' ×1'' Cs2LiYCl6 (CLYC) detectors has been commissioned for low energy nuclear science. Standard CLYC crystals detect both gamma rays and neutrons rays with excellent pulse shape discrimination, with thermal neutrons detected via the 6Li(n, α)t reaction. Our discovery of spectroscopy-grade response of CLYC for fast neutrons via the 35Cl(n,p) reaction, with a pulse height resolution of under 10 % in the < 8 MeV range, led to our present array of 7Li enriched C7LYC detectors, where the large thermal neutron response is essentially eliminated. While the intrinsic efficiency of C7LYC for fast neutron detection is low, the array can be placed near the target since a long TOF arm is no longer needed for neutron energy measurement, thus recovering efficiency through increased solid angle coverage. The array was recently deployed at Los Alamos to test its capability in measuring differential scattering cross sections as a function of energy for 56Fe and 238U. The incident energy from a white neutron source was measured via TOF, and the scattered neutron energy via the pulse height. Techniques, analysis and first results will be discussed. Supported by the NNSA Stewardship Science Academic Alliance Program under Grant DE-NA00013008.
High energy asymptotics of the scattering amplitude for the ...
Indian Academy of Sciences (India)
R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22
High energy asymptotics of the scattering amplitude for the. Schrödinger equation. D YAFAEV. Department of Mathematics, University Rennes-1, Campus Beaulieu, 35042 Rennes,. France. Abstract. We find an explicit function approximating at high energies the kernel of the scattering matrix with arbitrary accuracy.
Nonperturbative QCD and elastic processes at CEBAF energies
Energy Technology Data Exchange (ETDEWEB)
Radyushkin, A.V. [Old Dominion Univ., Norfolk, VA (United States)]|[Continuous Electron Beam Accelerator Facility, Newport News, VA (United States)
1994-04-01
The author outlines how one can approach nonperturbative aspects of the QCD dynamics studying elastic processes at energies accessible at upgraded CEBAF. The author`s point is that, in the absence of a complete theory of the nonperturbative effects, a possible way out is based on a systematic use of the QCD factorization procedure which separates theoretically understood ({open_quotes}known{close_quotes}) short-distance effects and nonperturbative ({open_quotes}unknown{close_quotes}) long-distance ones. The latter include hadronic distribution amplitudes, soft components of hadronic form factors etc. Incorporating the QCD sum rule version of the QCD factorization approach, one can relate these nonperturbative functions to more fundamental objects, vacuum condensates, which accumulate information about the nonperturbative structure of the QCD vacuum. The emerging QCD sum rule picture of hadronic form factors is characterized by a dominant role of essentially nonperturbative effects in the few GeV region, with perturbative mechanisms starting to show up for momentum transfers Q{sup 2} closer to 10 GeV{sup 2} and higher. Thus, increasing CEBAF energy provides a unique opportunity for a precision study of interplay between the perturbative and nonperturbative phenomena in the QCD description of elastic processes.
An IBEM solution to the scattering of plane SH-waves by a lined tunnel in elastic wedge space
Liu, Zhongxian; Liu, Lei
2015-02-01
The indirect boundary element method (IBEM) is developed to solve the scattering of plane SH-waves by a lined tunnel in elastic wedge space. According to the theory of single-layer potential, the scattered-wave field can be constructed by applying virtual uniform loads on the surface of lined tunnel and the nearby wedge surface. The densities of virtual loads can be solved by establishing equations through the continuity conditions on the interface and zero-traction conditions on free surfaces. The total wave field is obtained by the superposition of free field and scattered-wave field in elastic wedge space. Numerical results indicate that the IBEM can solve the diffraction of elastic wave in elastic wedge space accurately and efficiently. The wave motion feature strongly depends on the wedge angle, the angle of incidence, incident frequency, the location of lined tunnel, and material parameters. The waves interference and amplification effect around the tunnel in wedge space is more significant, causing the dynamic stress concentration factor on rigid tunnel and the displacement amplitude of flexible tunnel up to 50.0 and 17.0, respectively, more than double that of the case of half-space. Hence, considerable attention should be paid to seismic resistant or anti-explosion design of the tunnel built on a slope or hillside.
Polarization in backward elastic $\\pi^{+}p$ scattering at 2.0, 3.5 and 4.0 GeV/c
Bradamante, Franco; Daum, C; Fidecaro, Giuseppe; Fidecaro, Maria; Giorgi, M; Kalmus, George Ernest; Penzo, Aldo L; Piemontese, L; Schiavon, Paolo; Stairs, D; Vascotto, Alessandro
1973-01-01
Data on polarization in backward elastic pi /sup +/p scattering at 2.0, 3.5 and 4.0 GeV/c are presented. The data at 2.0 GeV/c are compared with the result of a recent phase shift analysis. The data at 3.5 and 4.0 GeV/c, and existing data above 3 GeV/c, show no significant energy dependence of the polarization over the measured u- range. A comparison with Regge models and with results from amplitude analysis made. (23 refs).
Jiang, Jian-jun; Li, He-ping; Dai, Li-dong; Hu, Hai-ying; Wang, Yan; Zhao, Chao-shuai
2015-09-01
In-situ experimental results on the elastic wave velocity of Earth materials at high pressure and high temperature in combination with data from seismic observation can help to inverse the chemical composition, state and migration of materials in Earth's interior, providing an important approach to explore information of deep earth. Applying the Brillouin scattering into the Diamond Anvil Cell (DAC) to obtain the in situ elastic wave velocities of minerals, is the important approach to investigate elastic properties of Earth's Interior. With the development of DAC technology, on the one hand, the high temperature and high pressure experimental environment to simulate different layers of the earth can be achieved; on the other hand, the optical properties of DAC made many kinds of optical analysis and test methods have been widely applied in this research field. In order to gain the elastic wave velocity under high temperature and high pressure, the accurate experimental pressure and heating temperature of the sample in the cavity should be measured and calibrated first, then the scattering signal needs to dealt with, using the Brillouin frequency shift to calculate the velocity in the sample. Combined with the lattice constants obtained from X ray technique, by a solid elastic theory, all the elastic parameters of minerals can be solved. In this paper, firstly, application of methods based on optical spectrum such as Brillouin and Raman scattering in elasticity study on materials in Earth's interior, and the basic principle and research progress of them in the velocity measurement, pressure and temperature calibration are described in detail. Secondly, principle and scope of application of two common methods of spectral pressure calibration (fluorescence and Raman spectral pressure standard) are analyzed, in addition with introduce of the application of two conventional means of temperature calibration (blackbody radiation and Raman temperature scale) in
Kim, Y J
1999-01-01
We analyze the elastic scattering of 800 MeV/c positive kaons from sup 1 sup 2 C and sup 4 sup 0 Ca nuclei within the framework of the McIntyre strong absorption model. The calculated differential cross-sections are found to be in excellent agreement with the observed data. Near- and far-side decompositions of the elastic cross-section have also been performed by following Fuller's formalism. The corresponding complex potentials are predicted by using the inversion procedure of the McIntyre S-matrix.
Color fluctuations in the nucleon in high-energy scattering.
Frankfurt, L; Strikman, M; Treleani, D; Weiss, C
2008-11-14
We study quantum fluctuations of the nucleon's parton densities by combining QCD factorization for hard processes with the notion of cross section fluctuations in soft diffraction. The fluctuations of the small-x gluon density are related to the ratio of inelastic and elastic vector meson production in ep scattering. A simple dynamical model explains the HERA data and predicts the x and Q2 dependence of the ratio. In pp/p[over ]p scattering, fluctuations enhance multiple hard processes (but cannot explain the Tevatron CDF data), and reduce gap survival in central exclusive diffraction.
Diagnosis of breast cancer using elastic-scattering spectroscopy: preliminary clinical results
Bigio, Irving J.; Brown, Stephen G.; Briggs, Gavin M.; Kelley, Christine; Lakhani, Sunil; Pickard, David; Ripley, Paul M.; Rose, Ian; Saunders, Christobel
2000-04-01
We report on the first stages of a clinical study designed to test elastic-scattering spectroscopy, medicated by fiberoptic probes, for three specific clinical applications in breast-tissue diagnosis: (1) a transdermal-needle (interstitial) measurement for instant diagnosis with minimal invasiveness similar to fine-needle aspiration but with sensitivity to a larger tissue volume, (2) a hand-held diagnostic probe for use in assessing tumor/resection margins during open surgery, and (3) use of the same probe for real-time assessment of the `sentinel' node during surgery to determine the presence or absence of tumor (metastatic). Preliminary results from in vivo measurements on 31 women are encouraging. Optical spectra were measured on 72 histology sites in breast tissue, and 54 histology sites in sentinel nodes. Two different artificial intelligence methods of spectral classification were studied. Artificial neural networks yielded sensitivities of 69% and 58%, and specificities of 85% and 93%, for breast tissue and sentinel nodes, respectively. Hierarchical cluster analysis yielded sensitivities of 67% and 91%, and specificities of 79% and 77%, for breast tissue and sentinel nodes, respectively. These values are expected to improve as the data sets continue to grow and more sophisticated data preprocessing is employed. The study will enroll up to 400 patients over the next two years.
Acoustic scattering by elastic cylinders of elliptical cross-section and splitting up of resonances
Energy Technology Data Exchange (ETDEWEB)
Ancey, S., E-mail: ancey@univ-corse.fr; Bazzali, E., E-mail: ebazzali@univ-corse.fr; Gabrielli, P., E-mail: gabrieli@univ-corse.fr; Mercier, M., E-mail: mercier@univ-corse.fr [UMR CNRS 6134 SPE, Faculté des Sciences, Université de Corse, F-20250 Corte (France)
2014-05-21
The scattering of a plane acoustic wave by an infinite elastic cylinder of elliptical cross section is studied from a modal formalism by emphasizing the role of the symmetries. More precisely, as the symmetry is broken in the transition from the infinite circular cylinder to the elliptical one, the splitting up of resonances is observed both theoretically and experimentally. This phenomenon can be interpreted using group theory. The main difficulty stands in the application of this theory within the framework of the vectorial formalism in elastodynamics. This method significantly simplifies the numerical treatment of the problem, provides a full classification of the resonances, and gives a physical interpretation of the splitting up in terms of symmetry breaking. An experimental part based on ultrasonic spectroscopy complements the theoretical study. A series of tank experiments is carried out in the case of aluminium elliptical cylinders immersed in water, in the frequency range 0 ≤ kr ≤ 50, where kr is the reduced wave number in the fluid. The symmetry is broken by selecting various cylinders of increasing eccentricity. More precisely, the greater the eccentricity, the higher the splitting up of resonances is accentuated. The experimental results provide a very good agreement with the theoretical ones, the splitting up is observed on experimental form functions, and the split resonant modes are identified on angular diagrams.
Hybrid Theory of P-Wave Electron-Hydrogen Elastic Scattering
Bhatia, Anand
2012-01-01
We report on a study of electron-hydrogen scattering, using a combination of a modified method of polarized orbitals and the optical potential formalism. The calculation is restricted to P waves in the elastic region, where the correlation functions are of Hylleraas type. It is found that the phase shifts are not significantly affected by the modification of the target function by a method similar to the method of polarized orbitals and they are close to the phase shifts calculated earlier by Bhatia. This indicates that the correlation function is general enough to include the target distortion (polarization) in the presence of the incident electron. The important fact is that in the present calculation, to obtain similar results only 35-term correlation function is needed in the wave function compared to the 220-term wave function required in the above-mentioned previous calculation. Results for the phase shifts, obtained in the present hybrid formalism, are rigorous lower bounds to the exact phase shifts.
Energy Technology Data Exchange (ETDEWEB)
Cullen, D.E.
1994-08-01
The computer code WALKMAN performs electron single collision elastic scattering Monte Carlo calculations in spherical or planar geometry. It is intended as a research tool to obtain results that can be compared to the results of condensed history calculations. This code is designed to be self documenting, in the sense that the latest documentation is included as comment lines at the beginning of the code. Printed documentation, such as this document, is periodically published and consists mostly of a copy of the comment lines from the code. The user should be aware that the comment lines within the code are continually updated to reflect the most recent status of the code and these comments should always be considered to be the most recent documentation for the code and may supersede published documentation, such as this document. Therefore, the user is advised to always read the documentation within the actual code. The remainder of this report consists of example results and a listing of the documentation which appears at the beginning of the code.
Elastic and inelastic neutron scattering cross sections for 12C at En = 5.9, 6.1, and 7.0 MeV
Lyons, Elizabeth; Hicks, Sally; Morin, Theodore; Derdeyn, Elizabeth; Peters, Erin
2017-09-01
Measurements of neutron elastic and inelastic scattering differential cross sections from 12C have been performed at incident neutron energies of 5.9, 6.1, and 7.0 MeV. Comparisons of existing experimental cross sections (NNDC) at these incident neutron energies reveal large discrepancies. Accurate measurements of 12C cross sections are vital to facilitate precise calculations regarding criticality conditions for nuclear reactors, advances in security screening methods, and better understanding astrophysical and nuclear phenomenon. During preliminary measurements of 12C cross sections at the University of Kentucky Accelerator Laboratory (UKAL), we realized the relative efficiency of the deuterated benzene (main) detector was needed over an unusually large range of neutron energies due to the high Q value of the first excited state of 12C. Those experiments were repeated during the summer of 2017 to measure in situ the relative detector efficiency with better beam conditions and a better understanding of background observed from the 2H(d, n)3He source reaction. The resulting improved detector efficiency was used in determining the neutron elastic and inelastic scattering cross sections. While the former were found to be in excellent agreement with evaluated cross sections from ENDF, the latter show some discrepancies, especially at 6.1 MeV. Our results will be presented. Research is supported by USDOE-NNSA-SSAP: NA0002931, NSF: PHY-1606890, and the Donald A. Cowan Physics Institute at the University of Dallas.
Energy Technology Data Exchange (ETDEWEB)
Vacheret, A
2004-12-01
Parity Violation asymmetry measurements in elastic electron scattering are in one hand an interesting way of retrieving new informations about the sea quarks of the nucleon and in the other hand a powerful test of the Standard Model electroweak sector at low energy. This thesis describes the HAPPEX experiment at JLab and the E-158 experiment at SLAC (USA) which measure de parity violation asymmetries in elastic scattering of polarized electron on nuclei like Hydrogen or Helium and on atomic electrons. With the measurements on hadronic targets one can extract the strange quarks contribution to the charge and current density of the nucleon. With the electron-electron scattering one can test the standard model at the loop level and far from the Z pole by extracting sin{sup 2} {theta}{sub W}. In this thesis we describe the formalism associated with the electroweak probe. We present in detail the experimental methods used to make such precise measurements of parity violation asymmetry. Then, we describe the experimental set-up of each experiment and in particular the electron detector and the feedback loop on the beam current for the HAPPEX experiment and the analysis of E-158 run III with a dedicated systematic study on the beam sub-pulse fluctuations. We present the preliminary results for each experiment with a comparison with the other existing results and the future experiments. (author)
Energy Technology Data Exchange (ETDEWEB)
Morcelle, V.; Lichtenthaeler, R.; Guimaraes, V.; Lepine-Szily, A.; Faria, P.N.; Camargo, O.; Barioni, A.; Mendes Junior, D.R.; Condori, R. P.; Zamora, J.C.; Morais, M.C.; Pires, K.C.C.; Scarduelli, V.; Leistenschneider, E.; Zagatto, V.A.B. [Universidade de Sao Paulo (USP), SP (Brazil); Shorto, J.M.B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Aguilera, E.F.; Martinez-Quiroz, E.; Lizcano, D. [Instituto Nacional de Investigaciones Nucleares, DF (Mexico); Kolata, J.; Lamm, L.O. [University of Notre Dame, Indiana (United States); Becchetti, F.; Jiang, H. [University of Michigan, Ann Arbor, MI (United States)
2011-07-01
Full text: The advent of radioactive beam production opened a new era in the nuclear physics, allowing the study of nuclei far from the beta stability line. One of the most interesting discoveries is the exotic structure of some of these unstable nuclei, which present the halo, such as {sup 6}He, {sup 11}Be, {sup 11}Li and others. During the last years, systems involving the neutron halo nuclei {sup 6}He have been extensively studied. In the case proton halo nuclei, on the other hand, the amount of available experimental data is very limited. The proton rich nucleus {sup 8}B is very interesting candidate as it has one proton very loosely bound (Sp = 138 KeV) to the {sup 7}Be core. Due to this low binding energy, the {sup 8}B is expected to be a proton halo and the dissociation {sup 8}B -- >{sup 7}Be+p in a collision {sup 8}B+target is expected to be very probable having a considerable effect in the total reaction cross section. We performed {sup 8}B+{sup 27}Al elastic scattering measurements at E{sub lab}= 16.0 and 22.0 MeV. The {sup 8}B beam has been produced by the reaction {sup 3}He({sup 6}Li,{sup 8}B)n and focused on a {sup 27}Al secondary target (2.1 mg/cm{sup 2}). Two experiments have been performed one at the RIBRAS system (Brazil) and another in Twinsol (USA). As the secondary beam is a cocktail of {sup 4}He, {sup 6}Li, {sup 7}Be, {sup 8}B particles, the {sup 7}Be+{sup 27}Al elastic angular distributions have been obtained as well. The elastic angular distributions were analyzed by optical model calculations, using Woods- Saxon potential and the total reaction cross sections have been obtained. The total reaction cross sections have been reduced using the Wong formula and the UFF equation being compared with others data from the literature. (author)
Energy Technology Data Exchange (ETDEWEB)
Patrick, Cheryl [Northwestern U.
2016-01-01
Next-generation neutrino oscillation experiments, such as DUNE and Hyper-Kamiokande, hope to measure charge-parity (CP) violation in the lepton sector. In order to do this, they must dramatically reduce their current levels of uncertainty, particularly those due to neutrino-nucleus interaction models. As CP violation is a measure of the difference between the oscillation properties of neutrinos and antineutrinos, data about how the less-studied antineutrinos interact is especially valuable. We present the MINERvA experiment's first double-differential scattering cross sections for antineutrinos on scintillator, in the few-GeV range relevant to experiments such as DUNE and NOvA. We also present total antineutrino-scintillator quasi-elastic cross sections as a function of energy, which we compare to measurements from previous experiments. As well as being useful to help reduce oscillation experiments' uncertainty, our data can also be used to study the prevalence of various cor relation and final-state interaction effects within the nucleus. We compare to models produced by different model generators, and are able to draw first conclusions about the predictions of these models.
Scaling of elastic energy storage in mammalian limb tendons: do small mammals really lose out?
Bullimore, Sharon R.; Burn, Jeremy F.
2005-01-01
It is widely believed that elastic energy storage is more important in the locomotion of larger mammals. This is based on: (a) comparison of kangaroos with the smaller kangaroo rat; and (b) calculations that predict that the capacity for elastic energy storage relative to body mass increases with size. Here we argue that: (i) data from kangaroos and kangaroo rats cannot be generalized to other mammals; (ii) the elastic energy storage capacity relative to body mass is not indicative of the imp...
Elastic scattering of a quark from a color field: Longitudinal momentum exchange
Jalilian-Marian, Jamal
2017-10-01
Perturbative QCD in the small Bjorken-x limit can be formulated as an effective theory known as the color glass condensate (CGC) formalism. The CGC formalism takes into account the dynamics of large gluon densities at small x and has been successfully applied to deep inelastic scattering (DIS) and particle production in high-energy hadronic and nuclear collisions in the small-x kinematic region. The effective degrees of freedom in CGC are Wilson lines which enter in the effective quark (and gluon) propagators and resum multiple soft scatterings from the small-x gluon field of the target. It is however known that the CGC effective theory breaks down when one probes the moderately large-x (high-pt) kinematics where collinear factorization and DGLAP evolution of parton distribution functions should be the right framework. Here we propose a general framework which may allow one to eventually unify the two approaches and to calculate perturbative QCD cross sections in both small and large Bjorken-x regions. We take the first step towards this goal by deriving an expression for the quark propagator in a background field which includes scatterings from both small- and large-x modes of the gluon field of the target. We describe how this quark propagator can be used to calculate QCD structure functions F2 and FL at all x and thus generalize the dipole model of DIS. We outline that this approach can also be used to extend the so-called hybrid approach to particle production in the forward rapidity region of high-energy hadronic and nuclear collisions to all x and pt regions and speculate on how one may apply the same techniques to extend the McLerran-Venugopalan effective action used in high-energy heavy-ion collisions to include high-pt physics.
Mitri, Farid G
2012-08-01
This work presents the general theory of resonance scattering (GTRS) by an elastic spherical shell immersed in a nonviscous fluid and placed arbitrarily in an acoustic beam. The GTRS formulation is valid for a spherical shell of any size and material regardless of its location relative to the incident beam. It is shown here that the scattering coefficients derived for a spherical shell immersed in water and placed in an arbitrary beam equal those obtained for plane wave incidence. Numerical examples for an elastic shell placed in the field of acoustical Bessel beams of different types, namely, a zero-order Bessel beam and first-order Bessel vortex and trigonometric (nonvortex) beams are provided. The scattered pressure is expressed using a generalized partial-wave series expansion involving the beam-shape coefficients (BSCs), the scattering coefficients of the spherical shell, and the half-cone angle of the beam. The BSCs are evaluated using the numerical discrete spherical harmonics transform (DSHT). The far-field acoustic resonance scattering directivity diagrams are calculated for an albuminoidal shell immersed in water and filled with perfluoropropane gas, by subtracting an appropriate background from the total far-field form function. The properties related to the arbitrary scattering are analyzed and discussed. The results are of particular importance in acoustical scattering applications involving imaging and beam-forming for transducer design. Moreover, the GTRS method can be applied to investigate the scattering of any beam of arbitrary shape that satisfies the source-free Helmholtz equation, and the method can be readily adapted to viscoelastic spherical shells or spheres.
Shi, Fan; Lowe, Mike; Craster, Richard
2017-06-01
Elastic waves scattered by random rough interfaces separating two distinct media play an important role in modeling phonon scattering and impact upon thermal transport models, and are also integral to ultrasonic inspection. We introduce theoretical formulas for the diffuse field of elastic waves scattered by, and transmitted across, random rough solid-solid interfaces using the elastodynamic Kirchhoff approximation. The new formulas are validated by comparison with numerical Monte Carlo simulations, for a wide range of roughness (rms σ ≤λ /3 , correlation length λ0≥ wavelength λ ), demonstrating a significant improvement over the widely used small-perturbation approach, which is valid only for surfaces with small rms values. Physical analysis using the theoretical formulas derived here demonstrates that increasing the rms value leads to a considerable change of the scattering patterns for each mode. The roughness has different effects on the reflection and the transmission, with a strong dependence on the material properties. In the special case of a perfect match of the wave speed of the two solid media, the transmission is the same as the case for a flat interface. We pay particular attention to scattering in the specular direction, often used as an observable quantity, in terms of the roughness parameters, showing a peak at an intermediate value of rms; this rms value coincides with that predicted by the Rayleigh parameter.
Energy dependence of scatter components in multispectral PET imaging.
Bentourkia, M; Msaki, P; Cadorette, J; Lecomte, R
1995-01-01
High resolution images in PET based on small individual detectors are obtained at the cost of low sensitivity and increased detector scatter. These limitations can be partially overcome by enlarging discrimination windows to include more low-energy events and by developing more efficient energy-dependent methods to correct for scatter radiation from all sources. The feasibility of multispectral scatter correction was assessed by decomposing response functions acquired in multiple energy windows into four basic components: object, collimator and detector scatter, and trues. The shape and intensity of these components are different and energy-dependent. They are shown to contribute to image formation in three ways: useful (true), potentially useful (detector scatter), and undesirable (object and collimator scatter) information to the image over the entire energy range. With the Sherbrooke animal PET system, restoration of detector scatter in every energy window would allow nearly 90% of all detected events to participate in image formation. These observations suggest that multispectral acquisition is a promising solution for increasing sensitivity in high resolution PET. This can be achieved without loss of image quality if energy-dependent methods are made available to preserve useful events as potentially useful events are restored and undesirable events removed.
Dominance of shear elastic energy far from a point defect in a solid
DEFF Research Database (Denmark)
Dyre, Jeppe
2007-01-01
It is shown that the elastic energy far from a point defect in an isotropic solid is mainly shear elastic energy. The calculation, which is based on a standard dipole expansion, shows that less than 10% of the distant point defect energy is associated with volume changes, no matter how large...... or small the bulk modulus is compared to the shear modulus....
Energy Technology Data Exchange (ETDEWEB)
Garvey, G. T. [Los Alamos; Harris, D. A. [Fermilab; Tanaka, H. A. [British Columbia U.; Tayloe, R. [Indiana U.; Zeller, G. P. [Fermilab
2015-06-15
The study of neutrino–nucleus interactions has recently seen rapid development with a new generation of accelerator-based neutrino experiments employing medium and heavy nuclear targets for the study of neutrino oscillations. A few unexpected results in the study of quasi-elastic scattering and single photon production have spurred a revisiting of the underlying nuclear physics and connections to electron–nucleus scattering. A thorough understanding and resolution of these issues is essential for future progress in the study of neutrino oscillations.
Excitation functions of the analyzing power in elastic proton-proton scattering from 0.45 to 2.5 GeV
Altmeier, M.; Bauer, F.; Bisplinghoff, J.; Büßer, K.; Busch, M.; Colberg, T.; Demirörs, L.; Engelhardt, H. P.; Eversheim, P. D.; Eyser, K. O.; Felden, O.; Gebel, R.; Glende, M.; Greiff, J.; Hinterberger, F.; Jonas, E.; Krause, H.; Lindemann, T.; Lindlein, J.; Lorentz, B.; Maier, R.; Maschuw, R.; Meinerzhagen, A.; Prasuhn, D.; Rohdjeß, H.; Rosendaal, D.; von Rossen, P.; Schirm, N.; Schwarz, V.; Scobel, W.; Trelle, H.-J.; Ulbrich, K.; Weise, E.; Wellinghausen, A.; Ziegler, R.
2005-02-01
Excitation functions AN(plab,Θc.m.) of the analyzing power in elastic proton-proton scattering have been measured in an internal target experiment at the Cooler Synchrotron COSY with an unpolarized proton beam and a polarized atomic hydrogen target. Data were taken continuously during the acceleration and deceleration for proton kinetic energies Tlab (momenta plab) between 0.45 and 2.5 GeV (1.0 and 3.3 GeV/c) and scattering angles 30 ° ⩽ Θc.m. ⩽ 90°. The results provide excitation functions and angular distributions of high precision and internal consistency. The data can be used as calibration standard between 0.45 and 2.5 GeV. They have significant impact on phase shift solutions, in particular on the spin triplet phase shifts between 1.0 and 1.8 GeV.
First measurement of 30S+α resonant elastic scattering for the 30S(α ,p ) reaction rate
Kahl, D.; Yamaguchi, H.; Kubono, S.; Chen, A. A.; Parikh, A.; Binh, D. N.; Chen, J.; Cherubini, S.; Duy, N. N.; Hashimoto, T.; Hayakawa, S.; Iwasa, N.; Jung, H. S.; Kato, S.; Kwon, Y. K.; Nishimura, S.; Ota, S.; Setoodehnia, K.; Teranishi, T.; Tokieda, H.; Yamada, T.; Yun, C. C.; Zhang, L. Y.
2018-01-01
Background: Type I x-ray bursts are the most frequently observed thermonuclear explosions in the galaxy, resulting from thermonuclear runaway on the surface of an accreting neutron star. The 30S(α ,p ) reaction plays a critical role in burst models, yet insufficient experimental information is available to calculate a reliable, precise rate for this reaction. Purpose: Our measurement was conducted to search for states in 34Ar and determine their quantum properties. In particular, natural-parity states with large α -decay partial widths should dominate the stellar reaction rate. Method: We performed the first measurement of 30S+α resonant elastic scattering up to a center-of-mass energy of 5.5 MeV using a radioactive ion beam. The experiment utilized a thick gaseous active target system and silicon detector array in inverse kinematics. Results: We obtained an excitation function for 30S(α ,α ) near 150∘ in the center-of-mass frame. The experimental data were analyzed with R -matrix calculations, and we observed three new resonant patterns between 11.1 and 12.1 MeV, extracting their properties of resonance energy, widths, spin, and parity. Conclusions: We calculated the resonant thermonuclear reaction rate of 30S(α ,p ) based on all available experimental data of 34Ar and found an upper limit about one order of magnitude larger than a rate determined using a statistical model. The astrophysical impact of these two rates has been investigated through one-zone postprocessing type I x-ray burst calculations. We find that our new upper limit for the 30S(α ,p )33Cl rate significantly affects the predicted nuclear energy generation rate during the burst.
Till, Ugo; Gaucher-Delmas, Mireille; Saint-Aguet, Pascale; Hamon, Glenn; Marty, Jean-Daniel; Chassenieux, Christophe; Payré, Bruno; Goudounèche, Dominique; Mingotaud, Anne-Françoise; Violleau, Frédéric
2014-12-01
Polymersomes formed from amphiphilic block copolymers, such as poly(ethyleneoxide-b-ε-caprolactone) (PEO-b-PCL) or poly(ethyleneoxide-b-methylmethacrylate), were characterized by asymmetrical flow field-flow fractionation coupled with quasi-elastic light scattering (QELS), multi-angle light scattering (MALS), and refractive index detection, leading to the determination of their size, shape, and molecular weight. The method was cross-examined with more classical ones, like batch dynamic and static light scattering, electron microscopy, and atomic force microscopy. The results show good complementarities between all the techniques; asymmetrical flow field-flow fractionation being the most pertinent one when the sample exhibits several different types of population.
Measurements of spin rotation parameter /A in pion-proton elastic scattering at 1.62 GeV/c
Alekseev, I. G.; Budkovsky, P. E.; Kanavets, V. P.; Koroleva, L. I.; Morozov, B. V.; Nesterov, V. M.; Ryltsov, V. V.; Svirida, D. N.; Sulimov, A. D.; Zhurkin, V. V.; Beloglazov, Y. A.; Kovalev, A. I.; Kruglov, S. P.; Novinsky, D. V.; Shchedrov, V. A.; Sumachev, V. V.; Trautman, V. Y.; Bazhanov, N. A.; Bunyatova, E. I.
2000-07-01
The ITEP-PNPI Collaboration presents the results of the measurements of the spin rotation parameter /A in the elastic scattering of positive and negative pions on protons at Pbeam=1.62 GeV/c. The setup included a longitudinally-polarized proton target with superconductive magnet, multiwire spark chambers and a carbon polarimeter with thick filter. Results are compared with the predictions of partial wave analyses. The experiment was performed at the ITEP proton synchrotron, Moscow.
Measurements of spin rotation parameter A in pion-proton elastic scattering at 1.62 GeV/c
Alekseev, I. G.; Budkovsky, P. E.; Kanavets, V. P.; Koroleva, L. I.; Morozov, B. V.; Nesterov, V. M.; Ryltsov, V. V.; Svirida, D. N.; Sulimov, A. D.; Zhurkin, V. V.; Beloglazov, Yu. A.; Kovalev, A. I.; Kruglov, S. P.; Novinsky, D. V.; Shchedrov, V. A.
2000-01-01
The ITEP-PNPI collaboration presents the results of the measurements of the spin rotation parameter A in the elastic scattering of positive and negative pions on protons at P_beam = 1.62 GeV/c. The setup included a longitudinally-polarized proton target with superconductive magnet, multiwire spark chambers and a carbon polarimeter with thick filter. Results are compared to the predictions of partial wave analyses. The experiment was performed at the ITEP proton synchrotron, Moscow.
Directory of Open Access Journals (Sweden)
Shimizu Y.
2010-04-01
Full Text Available Measurements of a complete set of deuteron analyzing powers (iT11, T20, T21, T22 for elastic deuteron–proton scattering at 250 MeV/nucleon have been performed with polarized deuteron beams at RIKEN RI Beam Factory. The obtained data are compared with the Faddeev calculations based on the modern nucleon–nucleon forces together with the Tucson-Melbourne’99, and UrbanaIX three nucleon forces.
Energy Technology Data Exchange (ETDEWEB)
Nishimura, Tomoaki, E-mail: t-nishi@hosei.ac.jp
2016-03-15
A computer simulation program for ion scattering and its graphical user interface (MEISwin) has been developed. Using this program, researchers have analyzed medium-energy ion scattering and Rutherford backscattering spectrometry at Ritsumeikan University since 1998, and at Rutgers University since 2007. The main features of the program are as follows: (1) stopping power can be chosen from five datasets spanning several decades (from 1977 to 2011), (2) straggling can be chosen from two datasets, (3) spectral shape can be selected as Gaussian or exponentially modified Gaussian, (4) scattering cross sections can be selected as Coulomb or screened, (5) simulations adopt the resonant elastic scattering cross section of {sup 16}O({sup 4}He, {sup 4}He){sup 16}O, (6) pileup simulation for RBS spectra is supported, (7) natural and specific isotope abundances are supported, and (8) the charge fraction can be chosen from three patterns (fixed, energy-dependent, and ion fraction with charge-exchange parameters for medium-energy ion scattering). This study demonstrates and discusses the simulations and their results.
Scattering of elastic waves from media with fracture-induced anisotropy
Energy Technology Data Exchange (ETDEWEB)
Haugen, Geir Ultveit
1996-12-31
To characterize oil reservoirs, one must know the fracture systems even at large distances from the reservoir and this knowledge comes from seismic data. This thesis models and analyses wave propagation in fractured rocks. It uses effective medium theory to include the fracturing and obtains closed form solutions for the resulting stiffness coefficients for several geometries. A linearized expression provides a simple way of calculating the first-order effects of the fracturing. For isotropic media with one set of embedded fractures, their effect upon the directional velocities is quantified. Compact formulas are given for the plane-wave scattering matrix for amplitudes and for vertical energy flux. When the norm of the relative difference in the eigenvector matrices is assumed to be small, this enables a weak-contrast/weak-anisotropy approximation of the scattering matrix in anisotropic media to be found. To obtain this, a simple formula is derived for the inverse of the eigenvector matrix regardless of the normalization. The new formalism is used to derive a new analytical approximation of the P-wave reflection coefficient in the crack-strike and the crack-normal plane for a model consisting of shale over vertically fractured sandstone. These approximations show how the fracture information can be obtained from the azimuthal AVO response. Next, the impact of the fracturing on the properties of the sandstone layer is quantified. Finally, using a linear slip boundary condition to model the non-weldedness, it is shown that a fracture or fault may be thought of as having a set of characteristic widths, which roughly specify the wavelength range of acoustic energy that interacts with the fracture. Compact plane wave scattering coefficients are derived. These show that observation of reflected signals can provide significant information on the physical properties of the fracture, such as texture and the nature of the in filling fluids. 75 refs., 20 figs., 3 tabs.
Measurement of Elastic Scattering and of Total Cross-Section at the CERN $\\bar{p}p$ Collider
2002-01-01
The aim of the experiment is to measure elastic scattering and the total cross-section at the $\\bar{p}p$ collider. \\\\ \\\\ Up to 1983 the experimental apparatus was composed of two parts : \\item 1) Telescopes of high accuracy drift and proportional chambers and counters inserted into vertically moveable sections of the vacuum chamber ('Roman pots'), detect elastic scattering in the angular region from .5 mrad up to about 3 mrad. \\item 2) The total inelastic rate is measured with a forward/backward system of drift chambers and counter hodoscopes and the UA2 central detector covering together @= 4@p solid angle. \\end{enumerate}\\\\ \\\\ With these two set-ups, the measured value of the total cross-section confirms extrapolation with (ln s)|2 behaviour. Elastic scattering and diffraction dissociation were measured in the range .03~$<$~-t~$<$~1.6~GeV|2. \\\\ \\\\ From 1984 on, six horizontally moveable ``Roman Pots'' have been installed farther away from the intersection region (up to 100~m). Using an especially desi...
High energy scattering in gravity and supergravity
DEFF Research Database (Denmark)
B. Giddings, Steven; Schmidt-Sommerfeld, Maximilian; Andersen, Jeppe Rosenkrantz
2010-01-01
We investigate features of perturbative gravity and supergravity by studying scattering in the ultraplanckian limit, and sharpen arguments that the dynamics is governed by long-distance physics. A simple example capturing aspects of the eikonal resummation suggests why short distance phenomena...... and in particular divergences or nonrenormalizability do not necessarily play a central role in this regime. A more profound problem is apparently unitarity. These considerations can be illustrated by showing that known gravity and supergravity amplitudes have the same long-distance behavior, despite the extra...... a physical scattering process, and ultraplanckian scattering exhibiting Regge behavior. These arguments sharpen the need to find a nonperturbative completion of gravity with mechanisms which restore unitarity in the strong gravity regime....
Turhan, Murat; Yaprak, Neslihan; Sircan-Kucuksayan, Aslinur; Ozbudak, Irem; Bostanci, Asli; Derin, Alper; Canpolat, Murat
2017-03-01
The elastic light single-scattering spectroscopy (ELSSS) system is a new tool for the real-time diagnosis of cancerous lesions. In the current study, we have employed ELSSS to investigate its ability in differentiation between normal and cancerous larynx tissues ex vivo. Basic science study in assessment of laryngeal malignancy using spectroscopy. ELSSS spectra of the larynx tissue were acquired using a single-fiber optical probe. Ex vivo spectroscopic measurements were acquired on 95 laryngeal lesions of 40 patients. Average slopes of the spectra in the wavelength range of 450 to 750 nm were calculated. The signs of the spectral slopes were positive for benign and negative for cancerous larynx tissues. Histopathology results were used as a gold standard to define sensitivity and specificity. The ELSSS system correctly defined 38 out of 41 malignant tissues as cancerous; three of them were misclassified as benign. All benign tissues were correctly classified. Moderate, severely dysplastic, and malignant tissues were correctly classified as cancerous. The system could not classify mild dysplastic tissues either benign or cancerous, whereas nearly half of them were classified as benign and the other half as malignant. The signs of the spectral slopes were used as a discrimination parameter between benign and cancerous (moderate, severely dysplastic, and malignant) lesions with a sensitivity and specificity of 94% and 100%, respectively. The ELSSS system has the potential to be used as an adjunctive tool in the diagnosis of cancerous laryngeal tissues in real time and noninvasively. This new diagnostic technique may reduce the number of negative biopsies. NA Laryngoscope, 127:611-615, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.
Acoustic formulation of elastic guided wave propagation and scattering in curved tubular structures.
Brath, Alex J; Simonetti, Francesco; Nagy, Peter B; Instanes, Geir
2014-05-01
Recently, the use of guided wave technology in conjunction with tomographic techniques has provided the possibility of obtaining point-by-point maps of corrosion or erosion depth over the entire volume of a pipeline section between two ring arrays of ultrasonic transducers. However, current research has focused on straight pipes and little work has been done on pipe bends and other curved tubular structures which are also the most susceptible to developing damage. Tomography of curved tubes is challenging because of the complexity and computational cost of the 3-D elastic model required to accurately describe guided wave propagation. Based on the definition of travel-time-preserving orthogonal parametric representations of curved tubes, this paper demonstrates that guided wave propagation and scattering can be approximated by an equivalent 2-D acoustic model which is inhomogeneous and elliptically anisotropic. Numerical methods to solve the full wave equation and predict ray paths and travel times are introduced and applied to the case of a bend. Particular emphasis is given to the shortest-path ray tracing method, which is applied to the 2-D model to compute ray paths and predict travel times of the fundamental flexural mode, A0, propagating across a curved pipe. Good agreement is found between predictions and experiments performed on a 220-mm-diameter (8-in-diameter) (D) pipe with 1.5D bend radius. The 2-D model also reveals the existence of an acoustic lensing effect which leads to a focusing phenomenon also confirmed by the experiments. The computational efficiency of the 2-D model makes it ideally suited for tomographic algorithms.
PREFACE: REXS 2013 - Workshop on Resonant Elastic X-ray Scattering in Condensed Matter
Beutier, G.; Mazzoli, C.; Yakhou, F.; Brown, S. D.; Bombardi, A.; Collins, S. P.
2014-05-01
The aim of this workshop was to bring together experts in experimental and theoretical aspects of resonant elastic x-ray scattering, along with researchers who are new to the field, to discuss important recent results and the fundamentals of the technique. The meeting was a great success, with the first day dedicated to students and new researchers in the field, who received introductory lectures and tutorials. All conference delegates were invited either to make an oral presentation or to present a poster, accompanied by a short talk. The first two papers selected for the REXS13 proceedings (Grenier & Joly and Helliwell) give a basic background to the theory of REXS and applications across a wide range of scientific areas. The remainder of the papers report on some of the latest scientific results obtained by applying the REXS technique to contemporary problems in condensed matter, materials and x-ray physics. It is hoped that these proceedings provide a snapshot of the current status of a vibrant and diverse scientific technique that will be of value not just to those who attended the workshop but also to any other reader with an interest in the subject. Local Scientific Committee REXS13 International Scientific Advisory Committee M Altarelli, European XFEL, Germany F de Bergevin, European Synchrotron Radiation Facility, France J Garcia-Ruiz, Universidad de Zaragoza, Spain A I Goldman, Iowa State University, USA M Goldmann, Institut Nanosciences, France T Schulli, European Synchrotron Radiation Facility, France C R Natoli, Laboratori Nazionali de Frascati, Italy G Materlik, Diamond Light Source, UK L Paolasini, European Synchrotron Radiation Facility, France U Staub, Paul Scherrer Institut, Switzerland K Finkelstein, Cornell University, USA Y Murakami, Photon Factory, Japan REXS13 Local Scientific Committee G Beutier, CNRS Grenoble, France C Mazzoli, Politecnico di Milano, Italy F Yakhou, European Synchrotron Radiation Facility, France S D Brown, XMaS UK CRG
Energy transfer in scattering by rotating potentials
Indian Academy of Sciences (India)
R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22
subspace of asymptotically free scattering states. 3. Evolution in a rotating frame. Here we study the time evolution in a rotating frame for potentials which no longer have to be smooth. This transformation yields an explicit formula for the propagator U(t,s) in terms of the unitary group for some time-independent generator.
Tables of phase shifts and experimental observables for p-/sup 4/He elastic scattering. [0 to 17 MeV
Energy Technology Data Exchange (ETDEWEB)
Dodder, D.C.; Hale, G.M.; Jarmie, N.; Witte, K.
1976-06-01
These tables contain calculated phase shifts and experimental observables for p-/sup 4/He elastic scattering from 0 to 17 MeV. The phase shifts are given at intervals suitable for linear interpolation.
Khoa, D T
2000-01-01
A generalized double-folding model for elastic and inelastic nucleus-nucleus scattering is presented. It is designed to accommodate effective nucleon-nucleon (NN) interactions that depend upon the density of nuclear matter in which the two nucleons are immersed. A recently parametrized density dependent M3Y interaction, based on the G-matrix elements of the Paris NN potential, has been used in the present folding calculation. The effects of knock-on exchange of the interacting nucleon pair are included in an accurate local approximation. Examples of the application of this model to study the refractive elastic and inelastic scattering data of sup 1 sup 2 C+ sup 1 sup 2 C and alpha+ sup 5 sup 8 sup , sup 6 sup 0 Ni systems are presented. A detailed comparison of the use of deformed optical potential (DP) and microscopic folded potential in the analysis of inelastic scattering has shown that the use of DP fails to reproduce the inelastic sup 1 sup 2 C+ sup 1 sup 2 C scattering data measured over a wide angular ...
Determination of the fast neutrons spectra by the Elastic scattering method (n, p)
Elizalde, J
1973-01-01
This work consists in determining the fast neutron spectra emitted by a Pu-Be isotopic source. The implemented technique is based in the spectrometry (n, p). This consists in making to fall on a fast neutrons beams (polyenergetic) over a thin film of hydrogenated material, detecting the spectra of emitted protons at a fix angle. The polyethylene film and the used solid state detector are inside of a vacuum chamber. The detector is placed at 30 degree with respect to direction of the incident neutrons beam. The protons spectra is stored in a multichannel. the energy is obtained with the prior calibration of the system. The data processing involves the transformation of the protons spectra observed at the falling on neutrons spectra over the film. The energy of the neutrons is related with that of the protons, according to the collision kinematical equations. The cross section of elastic collision of the neutrons with the hydrogen atoms is obtained from literature. Applying these relations to the observed spect...
High energy scattering in gravity and supergravity
Giddings, Steven B; Andersen, Jeppe R
2010-01-01
We investigate features of perturbative gravity and supergravity by studying scattering in the ultraplanckian limit, and sharpen arguments that the dynamics is governed by long-distance physics. A simple example capturing aspects of the eikonal resummation suggests why short distance phenomena and in particular divergences or nonrenormalizability do not necessarily play a central role in this regime. A more profound problem is apparently unitarity. These considerations can be illustrated by showing that known gravity and supergravity amplitudes have the same long-distance behavior, despite the extra light states of supergravity, and this serves as an important check on long-range dynamics in a context where perturbative amplitudes are finite. We also argue that these considerations have other important implications: they obstruct probing the conjectured phenomenon of asymptotic safety through a physical scattering process, and gravity appears not to reggeize. These arguments sharpen the need to find a nonpert...
Energy deposition model based on electron scattering cross section data from water molecules
Energy Technology Data Exchange (ETDEWEB)
Munoz, A; Oiler, J C [Centra de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT), Avenida Complutense 22, 28040 Madrid (Spain); Blanco, F [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, Avenida Complutense s.n., 28040 Madrid (Spain); Gorfinkiel, J D [Department of Physiscs and Astronomy, The Open University, Walton Hall, Milton Keynes MK7 6AA (United Kingdom); Limao-Vieira, P [Departamento de Fisica, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Maira-Vidal, A; Borge, M J G; Tengblad, O [Instituto de Estructura de la Materia, Consejo Superior de Investigaciones Cientificas (CSIC), Serrano 113-bis, 28006 Madrid, Spam (Spain); Huerga, C; Tellez, M [Hospital Universitario La Paz, paseo de la Castellana 261, 28046 Madrid (Spain); Garcia, G [Instituto de Matematicas y Fisica Fundamental, Consejo Superior de Investigaciones CientifIcas (CSIC), Serrano 113-bis, 28006 Madrid (Spain)], E-mail: g.garcia@imaff.cfmac.csic.es
2008-10-01
A complete set of electrons scattering cross sections by water molecules over a broad energy range, from the me V to the Me V ranges, is presented in this study. These data have been obtained by combining experiments and calculations and cover most relevant processes, both elastic and inelastic, which can take place in the considered energy range. A new Monte Carlo simulation programme has been developed using as input parameter these cross sectional data as well as experimental energy loss spectra. The simulation procedure has been applied to obtain electron tracks and energy deposition plots in water when irradiated by a Ru-106 plaque as those used for brachytherapy of ocular tumours. Finally, the low energy electron tracks provided by the present model have been compared with those obtained with other codes available in the literature.
Finite energy bounds for $\\piN$ scattering
Grassberger, P; Schwela, D
1974-01-01
Upper bounds on energy averaged pi N cross sections are given. Using low energy data and data from pi N backward scattering and NN to pi pi annihilation, it is found that sigma /sub tot/
Scattering of {sup 6}He at energies around the Coulomb barrier
Energy Technology Data Exchange (ETDEWEB)
Sanchez-BenItez, A M [Departamento de Fisica Aplicada, Universidad de Huelva, E-21071 Huelva (Spain); Escrig, D [Instituto de Estructura de la Materia, CSIC, E-28006 Madrid (Spain); Alvarez, M A G [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, E-41080 Sevilla (Spain)] [and others
2005-10-01
We have measured elastic cross sections of the scattering of {sup 6}He at E{sub Lab} = 14, 16, 17, 18 and 22 MeV on {sup 208}Pb in the angular ranges of 20 deg. - 64 deg. and 135 deg. - 170 deg. A significant amount of {sup 4}He events is found at energies well below the Coulomb barrier, that becomes dominant above it. Optical model calculations have been performed including a dynamic polarization potential. Very large imaginary diffuseness parameter is needed in order to describe the experimental distributions.
Study of forward elastic $pp$ scattering at $\\sqrt{s}=8\\text{ TeV}$ with the ALFA detector
Stark, Simon Holm; Hansen, Jørgen Beck
The elastic $pp$ scattering data analyzed in this thesis was taken at the LHC with the ALFA detector at $\\sqrt{s}=8\\text{ TeV}$ with a $\\beta^*=1\\text{ km}$ collision optics which gave access to the Coulomb-Nuclear-Interference region. An improved procedure was used to fit the observed number of elastic events as a function of the four-momentum transfer with a simulation based on theoretical expectations including experimental effects. The data can not exclude any of the investigated parametrizations for the modulus of the nuclear amplitude. The fit results for the total $pp$ cross section, $\\sigma_\\text{tot}$, and the ratio of the real to imaginary forward elastic scattering amplitude, $\\rho$, are: \\begin{align*} \\sigma_\\text{tot} &= 99.1\\pm 0.3 \\text{ (stat.)}\\pm1.6\\text{ (syst.)} \\text{ mb}\\;,\\\\ \\rho &= 0.166\\pm0.017\\text{ (stat.)}\\pm0.019\\text{ (syst.)}\\;, \\end{align*} which are in agreement with previous measurements. As part of the analysis, the detector distance to the beam was determined with ...
Modeling the elastic energy of alloys: Potential pitfalls of continuum treatments.
Baskaran, Arvind; Ratsch, Christian; Smereka, Peter
2015-12-01
Some issues that arise when modeling elastic energy for binary alloys are discussed within the context of a Keating model and density-functional calculations. The Keating model is a simplified atomistic formulation based on modeling elastic interactions of a binary alloy with harmonic springs whose equilibrium length is species dependent. It is demonstrated that the continuum limit for the strain field are the usual equations of linear elasticity for alloys and that they correctly capture the coarse-grained behavior of the displacement field. In addition, it is established that Euler-Lagrange equation of the continuum limit of the elastic energy will yield the same strain field equation. This is the same energy functional that is often used to model elastic effects in binary alloys. However, a direct calculation of the elastic energy atomistic model reveals that the continuum expression for the elastic energy is both qualitatively and quantitatively incorrect. This is because it does not take atomistic scale compositional nonuniformity into account. Importantly, this result also shows that finely mixed alloys tend to have more elastic energy than segregated systems, which is the exact opposite of predictions made by some continuum theories. It is also shown that for strained thin films the traditionally used effective misfit for alloys systematically underestimate the strain energy. In some models, this drawback is handled by including an elastic contribution to the enthalpy of mixing, which is characterized in terms of the continuum concentration. The direct calculation of the atomistic model reveals that this approach suffers serious difficulties. It is demonstrated that elastic contribution to the enthalpy of mixing is nonisotropic and scale dependent. It is also shown that such effects are present in density-functional theory calculations for the Si-Ge system. This work demonstrates that it is critical to include the microscopic arrangements in any elastic
Baxter, D; Chen, C J; Crisler, M; Cwiok, T; Dahl, C E; Grimsted, A; Gupta, J; Jin, M; Puig, R; Temples, D; Zhang, J
2017-06-09
A 30-g xenon bubble chamber, operated at Northwestern University in June and November 2016, has for the first time observed simultaneous bubble nucleation and scintillation by nuclear recoils in a superheated liquid. This chamber is instrumented with a CCD camera for near-IR bubble imaging, a solar-blind photomultiplier tube to detect 175-nm xenon scintillation light, and a piezoelectric acoustic transducer to detect the ultrasonic emission from a growing bubble. The time of nucleation determined from the acoustic signal is used to correlate specific scintillation pulses with bubble-nucleating events. We report on data from this chamber for thermodynamic "Seitz" thresholds from 4.2 to 15.0 keV. The observed single- and multiple-bubble rates when exposed to a ^{252}Cf neutron source indicate that, for an 8.3-keV thermodynamic threshold, the minimum nuclear recoil energy required to nucleate a bubble is 19±6 keV (1σ uncertainty). This is consistent with the observed scintillation spectrum for bubble-nucleating events. We see no evidence for bubble nucleation by gamma rays at any of the thresholds studied, setting a 90% C.L. upper limit of 6.3×10^{-7} bubbles per gamma interaction at a 4.2-keV thermodynamic threshold. This indicates stronger gamma discrimination than in CF_{3}I bubble chambers, supporting the hypothesis that scintillation production suppresses bubble nucleation by electron recoils, while nuclear recoils nucleate bubbles as usual. These measurements establish the noble-liquid bubble chamber as a promising new technology for the detection of weakly interacting massive particle dark matter and coherent elastic neutrino-nucleus scattering.
Baxter, D.; Chen, C. J.; Crisler, M.; Cwiok, T.; Dahl, C. E.; Grimsted, A.; Gupta, J.; Jin, M.; Puig, R.; Temples, D.; Zhang, J.
2017-06-01
A 30-g xenon bubble chamber, operated at Northwestern University in June and November 2016, has for the first time observed simultaneous bubble nucleation and scintillation by nuclear recoils in a superheated liquid. This chamber is instrumented with a CCD camera for near-IR bubble imaging, a solar-blind photomultiplier tube to detect 175-nm xenon scintillation light, and a piezoelectric acoustic transducer to detect the ultrasonic emission from a growing bubble. The time of nucleation determined from the acoustic signal is used to correlate specific scintillation pulses with bubble-nucleating events. We report on data from this chamber for thermodynamic "Seitz" thresholds from 4.2 to 15.0 keV. The observed single- and multiple-bubble rates when exposed to a Cf 252 neutron source indicate that, for an 8.3-keV thermodynamic threshold, the minimum nuclear recoil energy required to nucleate a bubble is 19 ±6 keV (1 σ uncertainty). This is consistent with the observed scintillation spectrum for bubble-nucleating events. We see no evidence for bubble nucleation by gamma rays at any of the thresholds studied, setting a 90% C.L. upper limit of 6.3 ×10-7 bubbles per gamma interaction at a 4.2-keV thermodynamic threshold. This indicates stronger gamma discrimination than in CF3 I bubble chambers, supporting the hypothesis that scintillation production suppresses bubble nucleation by electron recoils, while nuclear recoils nucleate bubbles as usual. These measurements establish the noble-liquid bubble chamber as a promising new technology for the detection of weakly interacting massive particle dark matter and coherent elastic neutrino-nucleus scattering.
Grillone, Gregory A; Wang, Zimmern; Krisciunas, Gintas P; Tsai, Angela C; Kannabiran, Vishnu R; Pistey, Robert W; Zhao, Qing; Rodriguez-Diaz, Eladio; A'Amar, Ousama M; Bigio, Irving J
2017-09-01
To evaluate the usefulness of elastic scattering spectroscopy (ESS) as a diagnostic adjunct to frozen section analysis in patients with diagnosed squamous cell carcinoma of the oral cavity. Prospective analytic study. Subjects for this single institution, institutional review board-approved study were recruited from among patients undergoing surgical resection for squamous cell cancer of the oral cavity. A portable ESS device with a contact fiberoptic probe was used to obtain spectral signals. Four to 10 spectral readings were obtained on each subject from various sites including gross tumor and normal-appearing mucosa in the surgical margin. Each reading was correlated with the histopathologic findings of biopsies taken from the exact location of the spectral readings. A diagnostic algorithm based on multidimensional pattern recognition/machine learning was developed. Sensitivity and specificity, error rate, and area under the curve were used as performance metrics for tests involving classification between disease and nondisease classes. Thirty-four (34) subjects were enrolled in the study. One hundred seventy-six spectral data point/biopsy specimen pairs were available for analysis. ESS distinguished normal from abnormal tissue, with a sensitivity ranging from 84% to 100% and specificity ranging from 71% to 89%, depending on how the cutoff between normal and abnormal tissue was defined (i.e., mild, moderate, or severe dysplasia). There were statistically significant differences in malignancy scores between histologically normal tissue and invasive cancer and between noninflamed tissue and inflamed tissue. This is the first study to evaluate the effectiveness of ESS in guiding mucosal resection margins in oral cavity cancer. ESS provides fast, real-time assessment of tissue without the need for pathology expertise. ESS appears to be effective in distinguishing between normal mucosa and invasive cancer and between "normal" tissue (histologically normal and mild
Laser diagnostics in combustion. Elastic scattering and picosecond laser-induced fluorescence
Energy Technology Data Exchange (ETDEWEB)
Ossler, Frederik
1999-05-01
Elastic scattering and the Lorenz-Mie (LM) theory in particular is used for the characterization of sub-micron- and micron-sized droplets of organic fuels in sprays and aerosols. Calculations on the Lorenz-Mie theory show that backward-sideward scattered visible radiation can be used for unambiguous detection of ensembles of homogeneous droplets of organic substances with diameters around 1 micrometer (size parameter between 2 and 6). A backward feature in the polarization ratio appears with a value considerably higher than one, on the opposite to the case of the rainbow observed for larger droplets. A comparison between measurements and LM calculations showed that a large amount of droplets in aerosols and well-atomized sprays were smaller than one micrometer in diameter. The LM theory was also used to characterize different size groups in a burning spray. A 3 - D technique based on a picosecond laser and a streak camera was demonstrated for measurements of fast and turbulent biphase flows. The entire 3 - D information was obtained within a time-span of less than 15 nanoseconds. A 2 - D technique for lifetime measurements based on a picosecond laser and a streak camera has been demonstrated on static objects. An analysis indicates that the technique may be applied to measurements of lifetimes around or below one picosecond employing femtosecond lasers and femtosecond streak-cameras. The technique may in principle be used to study dynamic systems when two detectors are used. Fluorescence lifetime measurements on hydrogen and oxygen atoms in flames at atmospheric pressure demonstrate the need of lasers with suiting spectral properties such as jitter and linewidth and the need of detectors with high sensitivity in the near IR in the case of oxygen atoms. The fluorescence lifetimes of gas phase acetone and 3-pentanone at 266 nm excitation wavelength have been measured for mixtures with nitrogen and air at temperatures between 323 and 723 K and pressures between 0
Electron scattering by Ne, Ar and Kr at intermediate and high energies, 0.5-10 keV
Energy Technology Data Exchange (ETDEWEB)
Garcia, G.; Roteta, M.; Manero, F. [Centro de Investigaciones Energeticas Medioambientales y Tecnologicas (CIEMAT), Departamento de Fusion y Particulas Elementales, Madrid (Spain); Blanco, F. [Universidad Complutense de Madrid, Facultad de Fisica, Departamento de Fisica Atomica Molecular y Nuclear, Madrid (Spain); Williart, A. [Universidad Nacional de Educacion a Distancia, Facultad de Ciencias, Departamento de Fisica de los Materiales, Madrid (Spain)
1999-04-28
Semi-empirical total cross sections for electron scattering of noble gases (Ne, Ar and Kr) in the energy range 0.5-10 keV have been obtained by combining transmission-beam measurements for impact energies up to 6 keV with an asymptotic behaviour at higher energies according to the Born-Bethe approximation. The influence of the forward electron scattering on the experimental system has been evaluated by means of a Monte Carlo electron transport simulation. Theoretical values have also been obtained by applying the Born approximation in the case of inelastic processes and by means of an atomic scattering potential for the elastic part. The results of these calculations show an excellent agreement with the semi-empirical values in the above-mentioned energy range. (author)
Energy Technology Data Exchange (ETDEWEB)
Ryan, Elaine A., E-mail: e.ryan@usyd.edu.a [Discipline of Medical Radiation Science, Faculty of Health Sciences, University of Sydney, NSW (Australia); Farquharson, Michael J. [Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario (Canada)
2010-07-21
The aim of this work was to investigate the differences in composition between malignant and non-malignant breast tissue. 38 invasive ductal carcinomas and 45 non-malignant breast tissues were measured, each being mounted in cylindrical sample holders of volume 25 mm{sup 2}. The experiments were performed at the European Synchrotron Radiation Facility (ESRF) at Grenoble, France. A monochromatic beam of 10 keV was used, focussed to a 0.5 mmx0.5 mm rectangular area on the sample. Elastic and inelastic scattered photons were collected at an angle of 120{sup o}. A novel technique was used to find the mean atomic numbers of the tissues (Z-bar). A CT scanner that has been calibrated with an ED phantom was used to find the Z-bar of 10 gels. These were composed of a gelatine base, with low concentrations of copper added to increase the Z-bar values by an incremental amount. These were then used to calibrate the scattering measurement system. The area of the elastic and inelastic scatter peaks were found using peak fitting software and the ratio of these two areas was obtained. The data was shown to be non-parametric, and was therefore analysed using a Mann-Whitney test. Using this analysis the difference between non-malignant and malignant tissues was found to be extremely significant, with a 2-tailed p-value of <0.0001. The absolute Z-bar values were also analysed.
Ryan, Elaine A.; Farquharson, Michael J.
2010-07-01
The aim of this work was to investigate the differences in composition between malignant and non-malignant breast tissue. 38 invasive ductal carcinomas and 45 non-malignant breast tissues were measured, each being mounted in cylindrical sample holders of volume 25 mm 2. The experiments were performed at the European Synchrotron Radiation Facility (ESRF) at Grenoble, France. A monochromatic beam of 10 keV was used, focussed to a 0.5 mm×0.5 mm rectangular area on the sample. Elastic and inelastic scattered photons were collected at an angle of 120°. A novel technique was used to find the mean atomic numbers of the tissues ( Z¯). A CT scanner that has been calibrated with an ED phantom was used to find the Z¯ of 10 gels. These were composed of a gelatine base, with low concentrations of copper added to increase the Z¯ values by an incremental amount. These were then used to calibrate the scattering measurement system. The area of the elastic and inelastic scatter peaks were found using peak fitting software and the ratio of these two areas was obtained. The data was shown to be non-parametric, and was therefore analysed using a Mann-Whitney test. Using this analysis the difference between non-malignant and malignant tissues was found to be extremely significant, with a 2-tailed p-value of <0.0001. The absolute Z¯ values were also analysed.
Pefoute, Eric; Martin-Gondre, Ludovic; Ollivier, Jacques; Soetens, Jean-Christophe; Russina, Margarita; Desmedt, Arnaud
2017-10-01
The dynamics of the THF molecule encapsulated in the type II clathrate hydrate matches the MD-QENS observation time (typically 0.1-10 ps) between 100 K and 270 K. Spatial and time characteristics of the THF molecule's dynamics obtained by means of MD simulations are in agreement with those experimentally determined by means of quasielastic neutron scattering. A detailed model of the THF dynamics is then proposed through the calculations of MD-derived properties. Reorientational relaxation has been observed on a timescale of 0.7 ± 0.1 ps at 270 K with activation energy of 3.0 ± 0.3 kJ/mol in addition to a highly damped rotational excitation occurring in the plane of the THF molecule with a period of ca. 2 ps. Moreover, the anisotropic cage energy landscape of the THF clathrate hydrate is revealed through a comprehensive investigation of THF orientational distribution functions, revealing the occurrence of preferred orientation of the THF molecule within the cage.
Multiple parton scattering in nuclei: Parton energy loss
Energy Technology Data Exchange (ETDEWEB)
Wang, Xin-Nian; Guo, Xiao-feng
2001-02-17
Multiple parton scattering and induced parton energy loss are studied in deeply inelastic scattering (DIS) off nuclei. The effect of multiple scattering of a highly off-shell quark and the induced parton energy loss is expressed in terms of the modification to the quark fragmentation functions. The authors derive such modified quark fragmentation functions and their QCD evolution equations in DIS using the generalized factorization of higher twist parton distributions. They consider double-hard and hard-soft parton scattering as well as their interferences in the same framework. The final result, which depends on both the diagonal and off-diagonal twist-four parton distributions in nuclei, demonstrates clearly the Landau-Pomeranchuk-Migdal interference features and predicts a unique nuclear modification of the quark fragmentation functions.
High-energy anomalous scattering: Is it semiclassical
Energy Technology Data Exchange (ETDEWEB)
Mattis, M.P. (Theoretical Division T-8, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)); McLerran, L. (Department of Physics, University of Minnesota, Minneapolis, MI (United States)); Yaffe, L.G. (Department of Physics, University of Washington, Seattle, Washington 98195 (United States))
1992-06-01
We discuss the possibility of a semiclassical evaluation of baryon-number-nonconserving scattering amplitudes at nonperturbative'' energies of order {ital M}{sub {ital W}}/{alpha}{sub {ital W}}. Semiclassical expansions around standard instanton configurations are known {ital not} to be valid at these energies: multiloop radiative corrections are not suppressed relative to tree-graph contributions. Despite this pathology, we present a conjecture showing how anomalous scattering at such nonperturbative energies may nevertheless remain semiclassically calculable, and discuss partial results supporting this conjecture. To determine the correct weak-coupling behavior of high-energy anomalous scattering amplitudes, we argue that one must solve a modified set of classical field equations, or equivalently sum suitably modified tree graphs.
Parity nonconservation in polarized electron scattering at high energies
Energy Technology Data Exchange (ETDEWEB)
Prescott, C.Y.
1979-10-01
Recent observations of parity violation in inelastic scattering of electrons at high energy is discussed with reference to the process e(polarized) + D(unpolarized) ..-->.. e + X. The kinetics of this process, the idealized case of scattering from free quark targets, experimental techniques and results, and relations to atomic physics of parity violation in bismuth and thallium atoms with a model independent analysis. 17 references. (JFP)
Measurement of the vector and tensor analyzing powers for dp-elastic scattering at 880 MeV
Energy Technology Data Exchange (ETDEWEB)
Kurilkin, P.K., E-mail: pkurilkin@jinr.ru [VBLHEP-JINR, 141980 Dubna, Moscow region (Russian Federation); Ladygin, V.P. [VBLHEP-JINR, 141980 Dubna, Moscow region (Russian Federation); Uesaka, T. [Center for Nuclear Study, University of Tokyo, Tokyo 113-0033 (Japan); Suda, K. [RIKEN Nishina Center, Wako, Saitama 351-0198 (Japan); Gurchin, Yu.V.; Isupov, A.Yu. [VBLHEP-JINR, 141980 Dubna, Moscow region (Russian Federation); Itoh, K. [Department of Physics, Saitama University, Saitama (Japan); Janek, M. [VBLHEP-JINR, 141980 Dubna, Moscow region (Russian Federation); Physics Department, University of Zilina, 010 26 Zilina (Slovakia); Karachuk, J.-T. [VBLHEP-JINR, 141980 Dubna, Moscow region (Russian Federation); Advanced Research Institute for Electrical Engineering, Bucharest (Romania); Kawabata, T. [Center for Nuclear Study, University of Tokyo, Tokyo 113-0033 (Japan); Khrenov, A.N.; Kiselev, A.S.; Kizka, V.A. [VBLHEP-JINR, 141980 Dubna, Moscow region (Russian Federation); Krasnov, V.A. [VBLHEP-JINR, 141980 Dubna, Moscow region (Russian Federation); Institute for Nuclear Research, Moscow (Russian Federation); Ladygina, N.B. [VBLHEP-JINR, 141980 Dubna, Moscow region (Russian Federation); Livanov, A.N. [VBLHEP-JINR, 141980 Dubna, Moscow region (Russian Federation); Institute for Nuclear Research, Moscow (Russian Federation); Maeda, Y. [Kyushi University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka-shi 812 (Japan); Malakhov, A.I.; Piyadin, S.M.; Reznikov, S.G. [VBLHEP-JINR, 141980 Dubna, Moscow region (Russian Federation); and others
2012-08-29
The vector A{sub y} and tensor analyzing powers A{sub yy} and A{sub xx} for dp-elastic scattering were measured at T{sub d}{sup lab}=880 MeV over the c.m. angular range from 60 Degree-Sign to 140 Degree-Sign at the JINR Nuclotron. The data are compared with predictions of different theoretical models based on the use of nucleon-nucleon forces only. The observed discrepancies of the measured analyzing powers from the calculations require the consideration of additional mechanisms.
Energy Technology Data Exchange (ETDEWEB)
Rohdjess, H.; Bisplinghoff, J.; Diehl, O.; Engelhardt, H.-P.; Eversheim, P.D.; Gross-Hardt, R.; Hinterberger, F.; Mosel, F.; Scheid, H.; Schwandt, F.; Trelle, H.J.; Wiedmann, W.; Ziegler, R. [Helmholtz-Institut fuer Strahlen- und Kernphysik, Universitaet Bonn (Germany); Albers, D. [Institut fuer Experimentalphysik, Universitaet Hamburg (Germany); Bollmann, R. [Institut fuer Experimentalphysik, Universitaet Hamburg (Germany); Buesser, K. [Institut fuer Experimentalphysik, Universitaet Hamburg (Germany); Dohrmann, F. [Institut fuer Experimentalphysik, Universitaet Hamburg (Germany); Gasthuber, M. [Institut fuer Experimentalphysik, Universitaet Hamburg (Germany); Greiff, J. [Institut fuer Experimentalphysik, Universitaet Hamburg (Germany); Gross, A. [Institut fuer Experimentalphysik, Universitaet Hamburg (Germany); Igelbrink, M. [Institut fuer Experimentalphysik, Universitaet Hamburg (Germany); Langkau, R. [Institut fuer Experimentalphysik, Universitaet Hamburg (Germany); Maier, R. [Institut fuer Kernphysik, Forschungszentrum Juelich (Germany); Mueller, M. [Institut fuer Experimentalphysik, Universitaet Hamburg (Germany); Muenstermann, M. [Institut fuer Experimentalphysik, Universitaet Hamburg (Germany); Prasuhn, D. [Institut fuer Kernphysik, Forschungszentrum Juelich (Germany); Rossen, P. von [Institut fuer Kernphysik, Forschungszentrum Juelich (Germany); Schirm, N. [Institut fuer Experimentalphysik, Universitaet Hamburg (Germany); Scobel, W. [Institut fuer Experimentalphysik, Universitaet Hamburg (Germany)]. E-mail: wolfgang.scobel@desy.de; Wellinghausen, A. [Institut fuer Experimentalphysik, Universitaet Hamburg (Germany); Woller, K. [Institut fuer Experimentalphysik, Universitaet Hamburg (Germany)
2006-01-01
The EDDA-detector at the cooler-synchrotron COSY/Julich has been operated with an internal CH{sub 2} fiber target to measure proton-proton elastic scattering differential cross-sections. For data analysis knowledge of beam parameters, like position, width and angle, are indispensable. We have developed a method to obtain these values with high precision from the azimuthal and polar angles of the ejectiles only, by exploiting the coplanarity of the two final-state protons with the beam and the kinematic correlation. The formalism is described and results for beam parameters obtained during beam acceleration are given.
Algorithmic scatter correction in dual-energy digital mammography
Energy Technology Data Exchange (ETDEWEB)
Chen, Xi; Mou, Xuanqin [Institute of Image Processing and Pattern Recognition, Xi' an Jiaotong University, Xi' an, Shaanxi 710049 (China); Nishikawa, Robert M.; Lau, Beverly A. [Department of Radiology, The University of Chicago, Chicago, Illinois 60637 (United States); Chan, Suk-tak [Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hung Hom (Hong Kong); Zhang, Lei [Department of Computing, The Hong Kong Polytechnic University, Hung Hom (Hong Kong)
2013-11-15
Purpose: Small calcifications are often the earliest and the main indicator of breast cancer. Dual-energy digital mammography (DEDM) has been considered as a promising technique to improve the detectability of calcifications since it can be used to suppress the contrast between adipose and glandular tissues of the breast. X-ray scatter leads to erroneous calculations of the DEDM image. Although the pinhole-array interpolation method can estimate scattered radiations, it requires extra exposures to measure the scatter and apply the correction. The purpose of this work is to design an algorithmic method for scatter correction in DEDM without extra exposures.Methods: In this paper, a scatter correction method for DEDM was developed based on the knowledge that scattered radiation has small spatial variation and that the majority of pixels in a mammogram are noncalcification pixels. The scatter fraction was estimated in the DEDM calculation and the measured scatter fraction was used to remove scatter from the image. The scatter correction method was implemented on a commercial full-field digital mammography system with breast tissue equivalent phantom and calcification phantom. The authors also implemented the pinhole-array interpolation scatter correction method on the system. Phantom results for both methods are presented and discussed. The authors compared the background DE calcification signals and the contrast-to-noise ratio (CNR) of calcifications in the three DE calcification images: image without scatter correction, image with scatter correction using pinhole-array interpolation method, and image with scatter correction using the authors' algorithmic method.Results: The authors' results show that the resultant background DE calcification signal can be reduced. The root-mean-square of background DE calcification signal of 1962 μm with scatter-uncorrected data was reduced to 194 μm after scatter correction using the authors' algorithmic method
Frauenfelder, Hans; Young, Robert D; Fenimore, Paul W
2017-05-16
We recently introduced a model of incoherent quasielastic neutron scattering (QENS) that treats the neutrons as wave packets of finite length and the protein as a random walker in the free energy landscape. We call the model ELM for "energy landscape model." In ELM, the interaction of the wave packet with a proton in a protein provides the dynamic information. During the scattering event, the momentum [Formula: see text] is transferred by the wave packet to the struck proton and its moiety, exerting the force [Formula: see text] The resultant energy [Formula: see text] is stored elastically and returned to the neutron as it exits. The energy is given by [Formula: see text], where [Formula: see text] is the ambient temperature and [Formula: see text] ([Formula: see text] 91 K Å) is a new elastobaric coefficient. Experiments yield the scattering intensity (dynamic structure factor) [Formula: see text] as a function of [Formula: see text] and [Formula: see text] To test our model, we use published data on proteins where only thermal vibrations are active. ELM competes with the currently accepted theory, here called the spatial motion model (SMM), which explains [Formula: see text] by motions in real space. ELM is superior to SMM: It can explain the experimental angular and temperature dependence, whereas SMM cannot do so.
Gazeau, F; Dubois, E; Perzynski, R
2003-01-01
We investigate the structure and dynamics of ionic magnetic fluids (MFs), based on ferrite nanoparticles, dispersed at pH approx 7 either in H sub 2 O or in D sub 2 O. Polarized and non-polarized static small angle neutron scattering (SANS) experiments in zero magnetic field allow us to study both the magnetic and the nuclear contributions to the neutron scattering. The magnetic interparticle attraction is probed separately from the global thermodynamic repulsion and compares well to direct magnetic susceptibility measurements. The magnetic interparticle correlation is in these fluid samples independent of the probed spatial scale. In contrast, a spatial dependence of the interparticle correlation is evidenced at large PHI by the nuclear structure factor. A model of magnetic interaction quantitatively explains the under-field anisotropy of the SANS nuclear contribution. In a quasi-elastic neutron spin-echo experiment, we probe the Brownian dynamics of translation of the nanoparticles in the range 1.3 sup<=...
Energy Technology Data Exchange (ETDEWEB)
Antchev, G.; Atanassov, I.; Broulim, P.; Eremin, V.; Georgiev, V.; Hammerbauer, J.; Linhart, R.; Oriunno, M.; Palocko, L.; Peroutka, Z. [University of West Bohemia, Pilsen (Czech Republic); Aspell, P.; Baechler, J.; Burkhardt, H.; Giani, S.; Karev, A.; Lucas Rodriguez, F.; Oliveri, E.; Palazzi, P.; Radermacher, E.; Ravotti, F.; Redaelli, S.; Ropelewski, L.; Ruggiero, G.; Salvachua, B.; Smajek, J.; Snoeys, W.; Valentino, G.; Wenninger, J. [CERN, Geneva (Switzerland); Avati, V. [AGH University of Science and Technology, Krakow (Poland); CERN, Geneva (Switzerland); Berardi, V.; Quinto, M. [INFN Sezione di Bari, Bari (Italy); Dipartimento Interateneo di Fisica di Bari, Bari (Italy); Berretti, M. [Universita degli Studi di Siena and Gruppo Collegato INFN di Siena, Siena (Italy); CERN, Geneva (Switzerland); Bossini, E.; Bottigli, U.; Latino, G.; Losurdo, L.; Turini, N. [Universita degli Studi di Siena and Gruppo Collegato INFN di Siena, Siena (Italy); Bozzo, M.; Lo Vetere, M. [INFN Sezione di Genova, Genoa (Italy); Universita degli Studi di Genova, Genoa (Italy); Buzzo, A.; Ferro, F.; Macri, M.; Minutoli, S.; Robutti, E. [INFN Sezione di Genova, Genoa (Italy); Cafagna, F.S.; Catanesi, M.G.; Fiergolski, A.; Mercadante, A.; Radicioni, E. [INFN Sezione di Bari, Bari (Italy); Campanella, C.E.; De Leonardis, F.; D' Orazio, A.; Guaragnella, C.; Passaro, V.; Petruzzelli, V.; Politi, T.; Prudenzano, F. [INFN Sezione di Bari, Bari (Italy); Dipartimento di Ingegneria Elettrica e dell' Informazione - Politecnico di Bari, Bari (Italy); Csanad, M.; Nemes, F.; Sziklai, J. [Wigner Research Centre for Physics, Budapest (Hungary); Csoergo, T. [Wigner Research Centre for Physics, Budapest (Hungary); KRF University College, Gyoengyoes (Hungary); Deile, M. [Dipartimento di Ingegneria Elettrica e dell' Informazione - Politecnico di Bari, Bari (Italy); Doubek, M.; Vacek, V. [Czech Technical University, Prague (Czech Republic); Eggert, K.; Niewiadomski, H.; Taylor, C. [Case Western Reserve University, Department of Physics, Cleveland, OH (United States); Garcia, F.; Heino, J.; Lauhakangas, R. [Helsinki Institute of Physics, Helsinki (Finland); Grzanka, L.; Wyszkowski, P.; Zielinski, K. [AGH University of Science and Technology, Krakow (Poland); Kaspar, J. [Institute of Physics of the Academy of Sciences of the Czech Republic, Prague (Czech Republic); CERN, Geneva (Switzerland); Kopal, J.; Kundrat, V.; Lokajicek, M.V.; Prochazka, J. [Institute of Physics of the Academy of Sciences of the Czech Republic, Prague (Czech Republic); Lami, S.; Scribano, A. [INFN Sezione di Pisa, Pisa (Italy); Lippmaa, E.; Lippmaa, J. [National Institute of Chemical Physics and Biophysics NICPB, Tallinn (Estonia); Minafra, N. [Dipartimento Interateneo di Fisica di Bari, Bari (Italy); CERN, Geneva (Switzerland); Naaranoja, T.; Oljemark, F.; Orava, R.; Oesterberg, K.; Saarikko, H.; Welti, J. [Helsinki Institute of Physics, Helsinki (Finland); University of Helsinki, Department of Physics, Helsinki (Finland)
2016-12-15
The TOTEM experiment at the CERN LHC has measured elastic proton-proton scattering at the centre-of-mass energy √(s) = 8 TeV and four-momentum transfers squared, vertical stroke t vertical stroke, from 6 x 10{sup -4} to 0.2 GeV{sup 2}. Near the lower end of the t-interval the differential cross-section is sensitive to the interference between the hadronic and the electromagnetic scattering amplitudes. This article presents the elastic cross-section measurement and the constraints it imposes on the functional forms of the modulus and phase of the hadronic elastic amplitude. The data exclude the traditional Simplified West and Yennie interference formula that requires a constant phase and a purely exponential modulus of the hadronic amplitude. For parametrisations of the hadronic modulus with second- or third-order polynomials in the exponent, the data are compatible with hadronic phase functions giving either central or peripheral behaviour in the impact parameter picture of elastic scattering. In both cases, the ρ-parameter is found to be 0.12 ± 0.03. The results for the total hadronic cross-section are σ{sub tot} = (102.9 ± 2.3) mb and (103.0 ± 2.3) mb for central and peripheral phase formulations, respectively. Both are consistent with previous TOTEM measurements. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Heinz, Christian; Stenzel, Hasko; Dueren, Michael [2. Physikalisches Institut, Universitaet Giessen (Germany)
2016-07-01
The ALFA (Absolute Luminosity for ATLAS) Roman Pot detector system is part of the forward instrumentation of ATLAS located about 240 m away from the interaction point in the LHC tunnel in both directions. ALFA consists of a scintillating fibre tracker housed in vertical Roman Pots which enables the measurement of elastic proton-proton scattering at small scattering angles. In 2012 data were recorded at a centre-of-mass energy of √(s) = 8 TeV during a fill with special beam optics of the LHC with β* = 90 m and parallel-to-point focusing. The four-momentum transfer t is measured for elastically scattered protons and used to extract the differential elastic cross section. In this talk a preliminary determination of the total cross section and of the slope of the elastic cross section at small vertical stroke t vertical stroke obtained from a fit to the differential cross section using the optical theorem is reported. In addition a second run at √(s) = 8 TeV with a special beam optics of β* = 1 km, providing access to the Coulomb-nuclear interference region, is being analysed. Preliminary analysis results from this run are presented as well.
AUTHOR|(CDS)2069260; Aspell, P.; Atanassov, I.; Avati, V.; Baechler, J.; Berardi, V.; Berretti, M.; Bossini, E.; Bottigli, U.; Bozzo, M.; Broulím, P.; Buzzo, A.; Cafagna, F.S.; Campanella, C.E.; Catanesi, M.G.; Csanád, M.; Csörgö, T.; Deile, M.; De Leonardis, F.; D'Orazio, A.; Doubek, M.; Eggert, K.; Eremin, V.; Ferro, F.; Fiergolski, A.; Garcia, F.; Georgiev, V.; Giani, S.; Grzanka, L.; Guaragnella, C.; Hammerbauer, J.; Heino, J.; Karev, A.; Kašpar, J.; Kopal, J.; Kundrát, V.; Lami, S.; Latino, G.; Lauhakangas, R.; Linhart, R.; Lippmaa, E.; Lippmaa, J.; Lokajíček, M.V.; Losurdo, L; Lo Vetere, M.; Lucas Rodriguez, F.; Macrí, M.; Mercadante, A.; Minafra, N.; Minutoli, S.; Naaranoja, T.; Nemes, F.; Niewiadomski, H.; Oliveri, E.; Oljemark, F.; Orava, R.; Oriunno, M.; Österberg, K.; Palazzi, P.; Paločko, L.; Passaro, V.; Peroutka, Z.; Petruzzelli, V.; Politi, T.; Procházka, J.; Prudenzano, F.; Quinto, M.; Radermacher, E.; Radicioni, E.; Ravotti, F.; Robutti, E.; Ropelewski, L.; Ruggiero, G.; Saarikko, H.; Scribano, A.; Smajek, J.; Snoeys, W.; Sziklai, J.; Taylor, C.; Turini, N.; Vacek, V.; Welti, J.; Wyszkowski, P.; Zielinski, K.
2016-01-01
The TOTEM experiment at the CERN LHC has measured elastic proton-proton scattering at the centre-of-mass energy $\\sqrt{s}$ = 8 TeV and four-momentum transfers squared, $|t|$, from $6\\times10^{-4}$ GeV$^2$ to 0.2 GeV$^2$. Near the lower end of the $t$-interval the differential cross-section is sensitive to the interference between the hadronic and the electromagnetic scattering amplitudes. This article presents the elastic cross-section measurement and the constraints it imposes on the functional forms of the modulus and phase of the hadronic elastic amplitude. The data exclude the traditional Simplified West and Yennie interference formula that requires a constant phase and a purely exponential modulus of the hadronic amplitude. For parametrisations of the hadronic modulus with second- or third-order polynomials in the exponent, the data are compatible with hadronic phase functions giving either central or peripheral behaviour in the impact parameter picture of elastic scattering. In both cases, the $\\rho$-pa...
The elastic scattering of polarized sup 3 He by sup 2 H at 22.5, 24, 27, 30 and 33 MeV
Okumusoglu, N T
2000-01-01
The angular distributions of the analysing power and the relative cross-sections for the elastic scattering of polarized sup 3 He nuclei by sup 2 H have been measured at incident sup 3 He energies of 22.5, 24, 27, 30 and 33 MeV. The data, considered in terms of fitted Legendre polynomials, clearly show a structure near 30 MeV sup 3 He energy which is more striking for odd L coefficients. In addition, our data, along with other data on the differential cross sections and on the analysing power for the scattering of polarized sup 2 H, have been analysed for the phase shifts and mixing parameters in the S-matrix description. The phase shifts selected are compared with those from resonating-group theory calculations. The prominent residual differences were attributed to further resonances which involve the formation of sup 5 Li nuclei at high excitation energy. Finally a level scheme is compared with the predictions of a multi-particle, multi-shell model calculation.
Energy Technology Data Exchange (ETDEWEB)
Devereux, M.J.
1979-05-01
Elastic pion scattering from /sup 9/Be, /sup 28/Si, /sup 58/Ni, and /sup 208/Pb at 162 MeV is analyzed and compared with an optical model theory which incorporates a pion--nucleon range. Excellent fits to the data are obtained in all but one case. The fitted values of the pion--nucleon range, as well as other fitted values are listed. 108 references.
Energy Technology Data Exchange (ETDEWEB)
Allgower, C.E.; Beddo, M.E.; Grosnick, D.P.; Kasprzyk, T.E.; Lopiano, D.; Spinka, H.M. [HEP Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439 (United States); Ball, J.; Beauvais, P.; Bedfer, Y.; Chamouard, P.; Combet, M.; Fontaine, J.; Kunne, R.; Lagniel, J.M.; Lemaire, J.L.; Milleret, G.; Sans, J. [Laboratoire National Saturne, CNRS/IN2P3 and CEA/DSM, CEA/Saclay, F-91191 Gif-sur-Yvette Cedex (France); Ball, J.; Bystricky, J.; Combet, M.; Fontaine, J.; Lehar, F.; Lesquen, A.d.; Mali, M.d. [DAPNIA, CEA/Saclay, F-91191 Gif-sur-Yvette Cedex (France); Barabash, L.S.; Borisov, N.; Janout, Z.; Kalinnikov, V.A.; Kazarinov, Y.M.; Khachaturov, B.A.; Matafonov, V.N.; Pisarev, I.L.; Popov, A.A.; Usov, Y.A. [Laboratory of Nuclear Problems, JINR, RU-141980 Dubna, Moscow Region (Russia); Boutefnouchet, A.; Ghazikhanian, V.; Whitten, C.A. [Physics Department, University of California at Los Angeles, 405 Hilgard Avenue, Los Angeles, California 90024 (United States); Demierre, P.; Hess, R.; Janout, Z.F.; Rapin, D.; Vuaridel, B. [DPNC, University of Geneva, 24 quai Ernest-Ansermet, CH-1211 Geneva 4 (Switzerland); Prokofiev, A.N.; Vikhrov, V.V.; Zhdanov, A.A. [Petersburg Nuclear Physics Institute, RU-188350 Gatchina (Russia)
1999-11-01
Experimental results are presented for the pp elastic-scattering single spin observable A{sub oono}=A{sub ooon}=A{sub N}=P, or the analyzing power, at 19 beam kinetic energies between 1795 and 2235 MeV. The typical c.m. angular range is 60{endash}100{degree}. The measurements were performed at Saturne II with a vertically polarized beam and target (transverse to the beam direction and scattering plane), a magnetic spectrometer and a recoil detector, both instrumented with multiwire proportional chambers, and beam polarimeters. {copyright} {ital 1999} {ital The American Physical Society}
Energy Technology Data Exchange (ETDEWEB)
Allgower, C. E.; Ball, J.; Barabash, L. S.; Beauvais, P.-Y.; Beddo, M. E.; Borisov, N.; Boutefnouchet, A.; Bystricky, J.; Chamouard, P.-A.; Combet, M. (and others)
2000-12-01
Measurements at 19 beam kinetic energies between 1795 and 2235 MeV are reported for the pp elastic scattering spin correlation parameter A{sub 00nn}=A{sub NN}=C{sub NN}. The c.m. angular range is typically 60--100{sup o}. The measurements were performed at Saturne II with a vertically polarized beam and target (transverse to the beam direction and scattering plane), a magnetic spectrometer and a recoil detector, both instrumented with multiwire proportional chambers, and beam polarimeters. These results are compared to previous data from Saturne II and elsewhere.
Liljequist, David
2012-01-01
Backscattering of very low energy electrons in thin layers of amorphous ice is known to provide experimental data for the elastic and inelastic cross sections and indicates values to be expected in liquid water. The extraction of cross sections was based on a transport analysis consistent with Monte Carlo simulation of electron trajectories. However, at electron energies below 20 eV, quantum coherence effects may be important and trajectory-based methods may be in significant error. This possibility is here investigated by calculating quantum multiple elastic scattering of electrons in a simple model of a very small, thin foil of amorphous ice. The average quantum multiple elastic scattering of electrons is calculated for a large number of simulated foils, using a point-scatterer model for the water molecule and taking inelastic absorption into account. The calculation is compared with a corresponding trajectory simulation. The difference between average quantum scattering and trajectory simulation at energies below about 20 eV is large, in particular in the forward scattering direction, and is found to be almost entirely due to coherence effects associated with the short-range order in the amorphous ice. For electrons backscattered at the experimental detection angle (45° relative to the surface normal) the difference is however small except at electron energies below about 10 eV. Although coherence effects are in general found to be strong, the mean free path values derived by trajectory-based analysis may actually be in fair agreement with the result of an analysis based on quantum scattering, at least for electron energies larger than about 10 eV.
Hard scattering in high-energy QCD
Mangano, Michelangelo L
2000-01-01
I review the recent results in the field of QCD at high energy presented to this Conference. In particular, I will concentrate on measurements of $\\as$ from studies of event structures and jet rates, jet production in hadronic collisions, and heavy quark production.
Fagundes, D. A.; Menon, M. J.; Silva, P. V. R. G.
2017-11-01
Forward amplitude analyses constitute an important approach in the investigation of the energy dependence of the total hadronic cross-section σtot and the ρ parameter. The standard picture indicates for σtot a leading log-squared dependence at the highest c.m. energies, in accordance with the Froissart-Lukaszuk-Martin bound and as predicted by the COMPETE Collaboration in 2002. Beyond this log-squared (L2) leading dependence, other amplitude analyses have considered a log-raised-to-gamma form (Lγ), with γ as a real free fit parameter. In this case, analytic connections with ρ can be obtained either through dispersion relations (derivative forms), or asymptotic uniqueness (Phragmén-Lindelöff theorems). In this work, we present a detailed discussion on the similarities and mainly the differences between the Derivative Dispersion Relation (DDR) and Asymptotic Uniqueness (AU) approaches and results, with focus on the Lγ and L2 leading terms. We also develop new Regge-Gribov fits with updated dataset on σtot and ρ from pp and p¯p scattering, including all available data in the region 5 GeV-8 TeV. The recent tension between the TOTEM and ATLAS results at 7 TeV and mainly at 8 TeV is discussed and considered in the data reductions. Our main conclusions are the following: (1) all fit results present agreement with the experimental data analyzed and the goodness-of-fit is slightly better in case of the DDR approach; (2) by considering only the TOTEM data at the LHC region, the fits with Lγ indicate γ ˜ 2.0 ± 0.2 (AU approach) and γ ˜ 2.3 ± 0.1 (DDR approach); (3) by including the ATLAS data the fits provide γ ˜ 1.9 ± 0.1 (AU) and γ ˜ 2.2 ± 0.2 (DDR); (4) in the formal and practical contexts, the DDR approach is more adequate for the energy interval investigated than the AU approach. A pedagogical and detailed review on the analytic results for σtot and ρ from the Regge-Gribov, DDR and AU approaches is presented. Formal and practical
Study of the Quasi-Elastic Scattering in the NOvA Detector Prototype
Energy Technology Data Exchange (ETDEWEB)
Betancourt, Minerba [Univ. of Minnesota, Minneapolis, MN (United States)
2013-06-01
NOvA is a 810 km long base-line neutrino oscillation experiment with two detectors (far 14 KTon and near detector 300 Ton) currently being installed in the NUMI o -axis neutrino beam produced at Fermilab. A 222 Ton prototype NOvA detector (NDOS) was built and operated in the neutrino beam for over a year to understand the response of the detector and its construction. The goal of this thesis is to study the muon neutrino interaction data collected in this test, specifically the identification of quasi-elastic charged-current interactions and measure the behavior of the quasi-elastic muon neutrino cross section.
Bauer, F.; Bisplinghoff, J.; Büßer, K.; Busch, M.; Colberg, T.; Demirörs, L.; Dahl, C.; Eversheim, P. D.; Eyser, O.; Felden, O.; Gebel, R.; Greiff, J.; Hinterberger, F.; Jonas, E.; Krause, H.; Lehmann, C.; Lindlein, J.; Maier, R.; Meinerzhagen, A.; Pauly, C.; Prasuhn, D.; Rohdjeß, H.; Rosendaal, D.; von Rossen, P.; Schirm, N.; Scobel, W.; Ulbrich, K.; Weise, E.; Wolf, T.; Ziegler, R.
2003-04-01
At the Cooler Synchrotron COSY/Jülich spin-correlation parameters in elastic proton-proton (pp) scattering have been measured with a 2.11GeV polarized proton beam and a polarized hydrogen atomic beam target. We report results for ANN, ASS, and ASL for c.m. scattering angles between 30° and 90°. Our data on ASS—the first measurement of this observable above 800MeV—clearly disagrees with predictions of available pp scattering phase-shift solutions while ANN and ASL are reproduced reasonably well. We show that in the direct reconstruction of the scattering amplitudes from the body of available pp elastic scattering data at 2.1GeV the number of possible solutions is considerably reduced.
Scattering of NH3 and ND3 with rare gas atoms at low collision energy.
Loreau, J; van der Avoird, A
2015-11-14
We present a theoretical study of elastic and rotationally inelastic collisions of NH3 and ND3 with rare gas atoms (He, Ne, Ar, Kr, Xe) at low energy. Quantum close-coupling calculations have been performed for energies between 0.001 and 300 cm(-1). We focus on collisions in which NH3 is initially in the upper state of the inversion doublet with j = 1, k = 1, which is the most relevant in an experimental context as it can be trapped electrostatically and Stark-decelerated. We discuss the presence of resonances in the elastic and inelastic cross sections, as well as the trends in the inelastic cross sections along the rare gas series and the differences between NH3 and ND3 as a colliding partner. We also demonstrate the importance of explicitly taking into account the umbrella (inversion) motion of NH3 in order to obtain accurate scattering cross sections at low collision energy. Finally, we investigate the possibility of sympathetic cooling of ammonia using cold or ultracold rare gas atoms. We show that some systems exhibit a large ratio of elastic to inelastic cross sections in the cold regime, which is promising for sympathetic cooling experiments. The close-coupling calculations are based on previously reported ab initio potential energy surfaces for NH3-He and NH3-Ar, as well as on new, four-dimensional, potential energy surfaces for the interaction of ammonia with Ne, Kr, and Xe, which were computed using the coupled-cluster method and large basis sets. We compare the properties of the potential energy surfaces corresponding to the interaction of ammonia with the various rare gas atoms.
Diffraction model analysis of pion-12C elastic scattering at 800 MeV/c
Indian Academy of Sciences (India)
Moreover, these phenomenological analyses show that pion–12C optical potential at 800 MeV/c is attractive whereas the first-order microscopic theories strongly suggest that it should be repulsive [2,4,5]. In the diffraction model an appropriate form for the elastic S-matrix Sl is chosen and its parameters are varied to obtain ...
thermoelastic waves without energy dissipation in an elastic plate ...
African Journals Online (AJOL)
cistvr
stress on the plate's boundary which is maintained at constant temperature. ... induced by a suddenly punched hole in an unbounded elastic plate, under the ..... Substituting for u and from (23) and (24) into (17), and equating the corresponding coefficients of the Bessel functions, we have α α α α. − ε. = A. mC s ms. B. T. 2. 2.
Scattered ionizing radiations from low-energy focus plasma and ...
Indian Academy of Sciences (India)
Scattered ionizing radiations from low-energy focus plasma and radiation dosimetery assessment. G M EL-ARAGI∗, M A AYAD, M A EL-KOLALY and .... 4000 system is in coaxial connection with a computer system which has a special software program for resolving TL-data and assorting the resolved data in classified files.
Scattering at zero energy for attractive homogeneous potentials
DEFF Research Database (Denmark)
Derezinski, Jan; Skibsted, Erik
2009-01-01
We compute up to a compact term the zero-energy scattering matrix for a class of potentials asymptotically behaving as −γ|x|−μ with 0 < μ < 2 and γ > 0. It turns out to be the propagator for the wave equation on the sphere at time ....
Energy Technology Data Exchange (ETDEWEB)
Ferraz, J.R.; Santos, A.S. dos [Departamento de Física, UFSCar, 13565-905 São Carlos, SP (Brazil); Souza, G.L.C. de; Lee, M.-T. [Departamento de Química, UFSCar, 13565-905 São Carlos, SP (Brazil); Brescansin, L.M. [Instituto de Física “Gleb Wataghin”, UNICAMP, 13083-970 Campinas, SP (Brazil); Lucchese, R.R. [Department of Chemistry, Texas A and M University, College Station, TX 7784-3255 (United States); Machado, L.E., E-mail: dlem@df.ufscar.br [Departamento de Física, UFSCar, 13565-905 São Carlos, SP (Brazil)
2014-03-01
Highlights: • Theoretical investigation on e{sup −}–CH{sub 3}F collisions. • Complex optical potential is used to evaluate elastic, total, and total absorption cross sections. • Single-center expansion, combined with the Padé approximant technique, is used to solve the scattering equations. • Calculated results are in good agreement with existing theoretical and experimental data. - Abstract: We report a theoretical study on electron scattering by methylfluoride (CH{sub 3}F) in the intermediate-energy range. Calculated elastic differential, integral, and momentum-transfer, as well as grand-total (elastic + inelastic) and total absorption cross sections are reported for impact energies ranging from 15 to 500 eV. A complex optical potential is used to represent the electron–molecule interaction dynamics. A theoretical method based on the single-center-expansion close-coupling framework and corrected by the Padé approximant technique is used to solve the scattering equations. The comparison of our calculated results with experimental and other available theoretical data is encouraging.
Energy Technology Data Exchange (ETDEWEB)
Wang, Biao [Southern Methodist U.
2017-01-01
We use the NOvA near detector and the NuMI beam at Fermilab to study the neutrino- electron elastic scattering and the muon neutrino magnetic process beyond the Standard Model physics. The particle identications of neutrino on electron elastic scattering are trained by using the multi-layer neural networks. This thesis provides a general discussion of this technique and shows a good agreement between data and MC for the neutrino-electron elastic weak scattering. So that beneting from the precise cross-section of this channel, we are able to tune the neutrino beam ux simulation in the future. Giving the exposure of 3:62 1020 POT in the NOvA near detector, we report 1:58 10
Planckian energy scattering and surface terms in the gravitational action
Fabbrichesi, Marco E; Veneziano, Gabriele; Vilkovisky, G A
1994-01-01
This is a revised version of our previous paper by the same name and preprint number. It contains various changes, two figures and new results in sect.5. We propose a new approach to four-dimensional Planckian-energy scattering in which the phase of the ${\\cal S}$-matrix is written---to leading order in $\\hbar$ and to all orders in $R/b =Gs/J$---in terms of the surface term of the gravity action and of a boundary term for the colliding quanta. The proposal is checked at the leading order in $R/b$ and also against some known examples of scattering in strong gravitational fields.
New Variational Techniques for Acoustic Radiation and Scattering From Elastic Shell Structures
1993-12-20
ELASTIC WHELL STUCTURES PRINCIPAL INVESTIGATOR: JURRY H. GINSBKRG SCHOOL OF MECHAMICAL INGINEZRING GEORGIA INSTITUTE OF TECHNOLOGY DTIC IS ELECTE JAN...cylinder, and a spheroid undergoing rigid body motion in the axial and beamwise direction, as well as a rotational oscillation about the centroid. The...computational view- point. Bessel and sinusoidal basis functions were shown to agree well with the analytical solution derived by Alper and Magrab, as were
Energy Technology Data Exchange (ETDEWEB)
Antoniassi, M.; Conceicao, A.L.C. [Departamento de Fisica e Matematica, Faculdade de Filosofia Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Ribeirao Preto, Sao Paulo (Brazil); Poletti, M.E., E-mail: poletti@ffclrp.usp.br [Departamento de Fisica e Matematica, Faculdade de Filosofia Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Ribeirao Preto, Sao Paulo (Brazil)
2011-10-01
In this work we have measured Compton and Rayleigh scattering radiation from normal (adipose and fibroglandular), benign (fibroadenoma) and malignant (ductal carcinoma) breast tissues using a monoenergetic beam of 17.44 keV and a scattering angle of 90{sup o} (x=0.99 A{sup -1}). A practical method using the area of Rayleigh and Compton scattering was used for determining the effective atomic number (Z{sub eff}) of the samples, being validated through measurements of several reference materials. The results show that there are differences in the distributions of Z{sub eff} of breast tissues, which are mainly related to the elemental composition of carbon (Z=6) and oxygen (Z=8) of each tissue type. The results suggest that is possible to use the method to characterize the breast tissues permitting study histological features of the breast tissues related to their elemental composition.
Antoniassi, M.; Conceição, A. L. C.; Poletti, M. E.
2011-10-01
In this work we have measured Compton and Rayleigh scattering radiation from normal (adipose and fibroglandular), benign (fibroadenoma) and malignant (ductal carcinoma) breast tissues using a monoenergetic beam of 17.44 keV and a scattering angle of 90° ( x=0.99 Å -1). A practical method using the area of Rayleigh and Compton scattering was used for determining the effective atomic number ( Zeff) of the samples, being validated through measurements of several reference materials. The results show that there are differences in the distributions of Zeff of breast tissues, which are mainly related to the elemental composition of carbon ( Z=6) and oxygen ( Z=8) of each tissue type. The results suggest that is possible to use the method to characterize the breast tissues permitting study histological features of the breast tissues related to their elemental composition.
Energy Technology Data Exchange (ETDEWEB)
Glass, G.; Bhatia, T.S.; Hiebert, J.C.; Kenefick, R.A.; Nath, S.; Northcliffe, L.C.; Tippens, W.B. (Texas A M University, College Station, Texas 77843 (United States)); Barlow, D.B. (Northwestern University, Evanston, Illinois 60201 (United States)); Jarmer, J.J.; Simmons, J.E. (Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)); Jeppesen, R.H. (University of Montana, Missoula, Montana 59812 (United States)); Tripard, G.E. (Washington State University, Pullman, Washington 99164 (United States))
1992-01-01
The spin-correlation observable {ital A}{sub {ital L}{ital L}} for {ital p}-{ital p} elastic scattering has been measured at energies 589, 640, 692, 743, and 793 MeV, over a c.m. angular range between 20{degree} and 100{degree}. The spin observable {ital A}{sub {ital S}{ital L}} was also measured in this angular range at energies 640 and 793 MeV. At 488 MeV both the spin observables were measured, but only near the c.m. angle of 90{degree}. The data are compared with the predictions of several phase-shift analyses and previous measurements. The energy dependence of {ital A}{sub {ital L}{ital L}} for the c.m. angle of 90{degree} is also presented and shows no anomalous behavior. These data provide better angular coverage over five of the energies, with comparable or better statistical precision, than previous measurements of {ital A}{sub {ital L}{ital L}}.
ELASTIC AND INELASTIC HELIUM ATOM SCATTERING AT A CLEAVED MICA SHEET
BRUSDEYLINS, G; SCHMICKER, D
1995-01-01
A mica sheet has been cleaved in situ in a UHV beam scattering apparatus. The diffraction of the helium atoms shows sharp Bragg peaks. In the [110] and [110] directions of the hexagonal surface the intensities of the Bragg peaks are analysed in terms of a sinusoidal corrugation. With hard wall
Munialo, C.D.; Linden, van der E.; Jongh, de H.H.J.
2016-01-01
The aim of this study was to relate the activation energy of the disruption of ovalbumin networks to elastically stored energy (i.e. recoverable energy, RE) obtained from mechanical deformation tests. To this end, heat-set ovalbumin gels were prepared at a fixed volume fraction and pH, but varying
Transverse energy distribution and hard constituent scattering in hadronic collisions
Directory of Open Access Journals (Sweden)
Torsten Åkesson
1983-01-01
Full Text Available We estimate the contributions to the total transverse energy spectrum from hard constituent scattering and the soft hadronic spectrum in hadron collisions. The transverse energy at which jet production starts to dominate is found to be essentially independent of the cms-energy (for large enough s and roughly a linear function of rapidity and azimuthal angle interval included. Calculations are presented for pp collisions at s= 25and60GeV, andp¯p interactions at s= 540GeV.
Excitation functions of the analyzing power in elastic proton-proton scattering from 0.45 to 2.5 GeV
Energy Technology Data Exchange (ETDEWEB)
Altmeier, M.; Bisplinghoff, J.; Busch, M.; Engelhardt, H.P.; Eversheim, D.; Glende, M.; Hinterberger, F. [Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik, Bonn (Germany); Bauer, F.; Buesser, K.; Colberg, T.; Demiroers, L.; Eyser, K.O.; Greiff, J.; Jonas, E.; Krause, H.; Lindemann, T.; Lindlein, J. [Universitaet Hamburg, Institut fuer Experimentalphysik, Hamburg (Germany); Felden, O.; Gebel, R.; Lorentz, B. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Maier, R.; Maschuw, R.; Meinerzhagen, A.; Prasuhn, D.; Rohdjess, H.; Rosendaal, D.; Von Rossen, P.; Schirm, N.; Schwarz, V.; Scobel, W.; Trelle, H.J.; Ulbrich, K.; Weise, E.; Wellinghausen, A.; Ziegler, R.
2005-02-01
Excitation functions A{sub N}(p{sub lab},{theta}{sub c.m.}) of the analyzing power in elastic proton-proton scattering have been measured in an internal target experiment at the Cooler Synchrotron COSY with an unpolarized proton beam and a polarized atomic hydrogen target. Data were taken continuously during the acceleration and deceleration for proton kinetic energies T{sub lab} (momenta p{sub lab}) between 0.45 and 2.5 GeV (1.0 and 3.3 GeV/c) and scattering angles 30 {<=}{theta}{sub c.m.}{<=}90 . The results provide excitation functions and angular distributions of high precision and internal consistency. The data can be used as calibration standard between 0.45 and 2.5 GeV. They have significant impact on phase shift solutions, in particular on the spin triplet phase shifts between 1.0 and 1.8 GeV. (orig.)
Zhang, S. L.; van der Laan, G.; Hesjedal, T.
2017-09-01
Long-wavelength spin spiral structures are ubiquitous in a large variety of magnetic materials. The detailed magnetic structure can take many variations owing to their different physical origins. Therefore, the unambiguous structural determination is crucial for understanding these spin systems, though such a task is experimentally challenging. Here, we show that ordered spin spiral structures can be fully determined in a single measurement by dichroic resonant elastic x-ray scattering using circularly polarized light. It is found that at certain geometrical conditions, the circular dichroism of the diffraction vanishes completely, revealing a one-to-one correspondence with the spin structure. We demonstrate both theoretically and experimentally this experimental principle, which allows for unambiguous structure determination immediately from the measured signal, whereby no modeling-based data refinement is needed. This largely expands the capabilities of conventional magnetic characterization techniques.
Energy Technology Data Exchange (ETDEWEB)
Stöhr, J.; Scherz, A.
2016-01-06
X-ray absorption by matter has long been described by the famous Beer-Lambert law. Here we show how this fundamental law needs to be modified for high-intensity coherent x-ray pulses, now available at x-ray free electron lasers, due to the onset of stimulated elastic forward scattering. We present an analytical expression for the modified polarization-dependent Beer-Lambert law for the case of resonant core-to-valence electronic transitions and incident transform limited x-ray pulses. Upon transmission through a solid, the absorption and dichroic contrasts are found to vanish with increasing x-ray intensity, with the stimulation threshold lowered by orders of magnitude through a super-radiative coherent effect. Our results have broad implications for the study of matter with x-ray lasers.
Guterman, L R; Falzone, J; Wilson, G E
1986-05-01
The effects of hydrochloric acid on mixed gels of aluminum and magnesium hydroxide and on magaldrate have been examined using quasi-elastic light scattering. Particles of magaldrate and mixed gels behave differently. The magaldrate particles initially decrease in size in response to increasing amounts of hydrochloric acid up to that sufficient to neutralize all the magnesium hydroxide present, then increase in size to approximately 2 microns. The composition of the mixed gels appears to be particularly important in determining the reaction with limited amounts of acid. For these particles, which are thought to consist of a magnesium hydroxide core surrounded by an aluminum hydroxide sheath, slow erosion of the aluminum hydroxide was apparently followed by complete disintegration of the particles. Particles which remain grow in size to approximately 3 microns.
Omelaenko, A S
2002-01-01
From the data of the P sub 3 sub 3 amplitude of several pi N elastic-scattering analyses the DELTA(1232)-pole characteristics are determined in the framework of a resonance model. The approximate analytical expression connecting the residue with a background value is obtained. The estimations have corroborated the small value of the non-resonant part of the phase shift being essentially different from the one calculated by the current algebra and the effective Lagrangian theory. This contradiction is removed in a modified variant of the resonance model developed by taking into account the quadratic term in the expansion of the Jost function in a series at the pole point. In comparison with the traditional model the pole coordinates and phase shift of the residue have been changed a little but its absolute value has increased by about 20%
WAVE SCATTERING AT A TAPERED FREE END OF AN ELASTIC PLATE
Directory of Open Access Journals (Sweden)
Yagoub Nassar Al-Nassar
2011-12-01
Full Text Available 0 0 1 169 965 International Islamic University 8 2 1132 14.0 Normal 0 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Times New Roman";} This paper focuses on the interaction of SH elastic waves in a plate with a tapered free end. The plate is modeled as a semi-infinite elastic structure, which was assumed to have traction-free surfaces. The results of the analysis based on mode matching are presented for various combinations of normalized frequencies and angles of free end inclination. The reported observations form important guidelines for the interpretation of experimental data when using horizontally polarized wave as a mean for nondestructive evaluation of elastic plates. ABSTRAK: Kertas kerja ini adalah khusus berkenaan interaksi gelombang anjal SH di dalam plat yang mempunyai hujung bebas yang tirus. Plat ini dimodelkan sebagai satu struktur elastik separa tak terhingga, yang diandaikan mempunyai permukaan nirgeseran. Keputusan analisis berdasarkan mod pemadanan dibentangkan untuk pelbagai kombinasi frekuensi ternormal dan sudut kecondongan hujung bebas. Pemerhatian yang dibentangkan memberi panduan penting dalam menginterpretasi data eksperimental penggunaan gelombang berkutub mendatar sebagai satu kaedah penilaian tanpa musnah plat anjal.
Hague, Charlotte V; Postle, Anthony D; Attard, George S; Dymond, Marcus K
2013-01-01
One of the most developed theories of phospholipid homeostasis is the intrinsic curvature hypothesis, which, in broad terms, postulates that cells regulate their lipid composition so as to keep constant the membrane stored curvature elastic energy. The implication of this hypothesis is that lipid composition is determined by a ratio control function consisting of the weighted sum of concentrations of type II lipids in the numerator and the weighted sum of concentrations of Type 0 lipids in the denominator. In previous work we used a data-driven approach, based on lipidomic data from asynchronous cell cultures, to determine a criterion that allows the different lipid species to be assigned to the set of type 0 or of type II lipids, and hence construct a ratio control function that serves as a proxy for the lipid contribution to total membrane stored curvature elastic energy in vivo. Here we apply the curvature elastic energy proxy to the analysis of lipid composition data from synchronous HeLa cells as they traverse the cell cycle. Our analysis suggests HeLa cells modify their membrane stored elastic energy through the cell cycle. In S-phase type 0 lipids are the most abundant, whilst in G2 type II lipids are most abundant. Changes in our proxy for membrane stored elastic energy correlate with membrane curvature dependent processes in the HeLa cell around division, providing some insights into the interplay between the individual lipid and protein contributions to membrane free energy.
Invester Response to Consumer Elasticity, Nordic Energy Research
DEFF Research Database (Denmark)
Jensen, Stine Grenaa; Meibom, Peter; Ravn, Hans V.
2004-01-01
the potential investors in new production capacity are unaccustomed with investments under the new regime, it is unknown if and when investments will take place. The electricity price is the key market signal to potential investors. The price is settled as a balance between supply and demand......, and it is generally assumed that the demand side has an important role in this, and increasingly so. However, since consumers have not earlier had the incentive to respond to electricity prices, no reliable estimate of demand elasticity is known. The purpose of the present study is to analyse the role of electricity...
Influence of energy dissipation on plane harmonic waves through a piezo-thermo-elastic medium
Atwa, Sarhan Y.; Nazeer, M.; Adnan, J.; Rehman, Nadia
2017-07-01
The concept of thermo-elasticity proposed by Green and Naghdi is employed to study the plane harmonic waves through a piezo-electric thermo-elastic medium. An analytical technique of normal modes is adopted to find the exact solution of the problem. The theoretical results obtained are represented graphically for the particular material. It is found that energy dissipation reduces the amplitude of waves propagating through the medium. The results fully agree with physical interpretation of the problem.
Characteristic energy range of electron scattering due to plasmaspheric hiss
Ma, Q.; Li, W.; Thorne, R. M.; Bortnik, J.; Reeves, G. D.; Kletzing, C. A.; Kurth, W. S.; Hospodarsky, G. B.; Spence, H. E.; Baker, D. N.; Blake, J. B.; Fennell, J. F.; Claudepierre, S. G.; Angelopoulos, V.
2016-12-01
We investigate the characteristic energy range of electron flux decay due to the interaction with plasmaspheric hiss in the Earth's inner magnetosphere. The Van Allen Probes have measured the energetic electron flux decay profiles in the Earth's outer radiation belt during a quiet period following the geomagnetic storm that occurred on 7 November 2015. The observed energy of significant electron decay increases with decreasing L shell and is well correlated with the energy band corresponding to the first adiabatic invariant μ = 4-200 MeV/G. The electron diffusion coefficients due to hiss scattering are calculated at L = 2-6, and the modeled energy band of effective pitch angle scattering is also well correlated with the constant μ lines and is consistent with the observed energy range of electron decay. Using the previously developed statistical plasmaspheric hiss model during modestly disturbed periods, we perform a 2-D Fokker-Planck simulation of the electron phase space density evolution at L = 3.5 and demonstrate that plasmaspheric hiss causes the significant decay of 100 keV-1 MeV electrons with the largest decay rate occurring at around 340 keV, forming anisotropic pitch angle distributions at lower energies and more flattened distributions at higher energies. Our study provides reasonable estimates of the electron populations that can be most significantly affected by plasmaspheric hiss and the consequent electron decay profiles.
Ge, Jianlong; Fan, Gang; Si, Yang; He, Jianxin; Kim, Hak-Yong; Ding, Bin; Al-Deyab, Salem S.; El-Newehy, Mohamed; Yu, Jianyong
2016-01-01
Flexible membranes created from porous carbon nanofibers (CNFs) hold great promise in the next generation wearable energy storage devices, but challenges still remain due to the poor mechanical properties of porous carbon nanofibers. Here, we report a facile strategy to fabricate elastic and hierarchical porous CNF membranes with NiFe2O4 nanocrystals embedded via multicomponent electrospinning and nano-doping methods. Benefiting from the scattering effect of NiFe2O4 nanocrystals and graphitized carbon layers for the condensed stress, the resultant CNF membranes exhibit an enhanced elasticity with a bending radius generation wearable energy storage devices, but challenges still remain due to the poor mechanical properties of porous carbon nanofibers. Here, we report a facile strategy to fabricate elastic and hierarchical porous CNF membranes with NiFe2O4 nanocrystals embedded via multicomponent electrospinning and nano-doping methods. Benefiting from the scattering effect of NiFe2O4 nanocrystals and graphitized carbon layers for the condensed stress, the resultant CNF membranes exhibit an enhanced elasticity with a bending radius Tables of solution properties and porous structures, figures showing mechanical properties and nanostructures, and movie S1. See DOI: 10.1039/c5nr07368e
Energy Technology Data Exchange (ETDEWEB)
Rahbar, A.A.
1982-09-01
A specific set of spin dependent parameters for elastic scattering of polarized protons from an unpolarized deuterium target have been measured over the angular range of 15/sup 0/ and 65/sup 0/ in the Laboratory system. The experiment was performed at the Los Alamos Meson Physics Facility (LAMPF) using a polarized proton beam of 0.5 and 0.8 GeV incident kinetic energy. A carbon analyzer was used to measure the scattered proton polarization. This comprises the first set of measurements in the intermediate energy range. Of particular interest, the analyzing power, (A/sub y/), has been measured for the pd elastic scattering reaction at both energies. A test of Time-Reversal Invariance (TRI) has been made for this reaction. This was accomplished by comparing the polarization (P) with the analyzing power A/sub y/ together with the depolarization parameter, (D), which was measured in this experiment. No evidence of time-reversal violation was found for this reaction in the region of non-zero spin flip probability. The measurements also furnished very useful and selective information on the p-d collision matrix, as well as the double-spin-flip nucleon-nucleon amplitudes.
Seismic energy transmission in an intensively scattering environment
Nakamura, Y.
1977-01-01
In order to account for some special features of lunar seismograms, namely, the gradual build-up of the signal, the extremely prolonged tail, and the lack of apparent coherence among three orthogonal components of ground motion, a statistical approach is proposed for describing transmission of seismic energy through a medium in which strong scattering takes place. A seismic diffusion theory is presented for a medium with randomly distributed scatterers of a given size distribution. A solution of the resulting diffusion equation for an impulsive energy source gives a curve which fairly closely reproduces the envelope of typical lunar impact seismograms. Since the model is based on constant diffusivity, long-range transmission will require a combination of diffusion and wave propagation treatments for accurate description.
Qin Liu; Lai Wei; Jianxun Chen; Yanbin Luo; Pei Huang; Hongyu Wang; Jiaqi Guo
2017-01-01
In this paper, the energy instability criterion of water-resistant strata and rock mass failure index (RMFI) are proposed, respectively, based on releasable elastic strain energy Ue. RMFI is employed to represent the damage extent of water-resistant strata. When RMFI1.0, rock mass is unstable. The releasable elastic strain energy Ue and RMFI program is performed by FISH programming language of Flac3D software. Then, the authors apply Flac3D software to analyze the distribution law of releasab...
Low-energy potential scattering in two and three dimensions
Khuri, N.N.; Richard, Jean-Marc; Wu, Tai Tsun
2009-01-01
Conditions are established for the existence of a scattering length and an effective range in the low-energy expansion of the S-wave phase-shift of a central potential in two and three dimensions. The behavior of the phase-shift as a function of the momentum is also derived for longer-range power-law potentials which do not fulfill these conditions.
Recent developments on high-energy gravitational scattering
CERN. Geneva
2015-01-01
After a quick reminder of earlier results I will discuss some recent progress in the high-energy gravitational scattering of particles, strings, and branes and, in particular: 1. Gravitational bremsstrahlung; 2. Causality constraints in the presence of higher derivative corrections; 3. Absorption of an energetic closed string by a stack of D-branes. These developments should eventually help us understand how information is preserved in the quantum analog of classical gravitational collapse.
Chiral unitary approach to {eta}'N scattering at low energies
Energy Technology Data Exchange (ETDEWEB)
Oset, E. [Departamento de Fisica Teorica and IFIC, Centro Mixto Universidad de Valencia-CSIC, Institutos de Investigacion de Paterna, Aptdo. 22085, 46071 Valencia (Spain); Ramos, A., E-mail: ramos@ecm.ub.es [Departament d' Estructura i Constituents de la Materia and Institut de Ciencies del Cosmos, Universitat de Barcelona, Avda. Diagonal 647, 08028 Barcelona (Spain)
2011-10-19
We study the {eta}'N interaction within a chiral unitary approach which includes {pi}N, {eta}N and related pseudoscalar meson-baryon coupled channels. Since the SU(3) singlet does not contribute to the standard interaction and the {eta}{sup '} is mostly a singlet, the resulting scattering amplitude is very small and inconsistent with the experimental scattering length. The additional consideration of vector meson-baryon states into the coupled channel scheme, via normal and anomalous couplings of pseudoscalar to vector mesons, enhances substantially the {eta}'N amplitude. We also exploit the freedom of adding to the Lagrangian a new term, allowed by the symmetries of QCD, which couples baryons to the singlet meson of SU(3). Adjusting the unknown strength to the {eta}'N scattering length, we obtain predictions for the elastic {eta}{sup '}N{yields}{eta}{sup '}N and inelastic {eta}{sup '}N{yields}{eta}N, {pi}N, K{Lambda}, K{Sigma} cross sections at low {eta}' energies, and discuss their significance.
Energy Technology Data Exchange (ETDEWEB)
Sargsyan, V.V. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Yerevan State University, Yerevan (Armenia); Adamian, G.G.; Antonenko, N.V. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Diaz-Torres, A. [European Centre for Theoretical Studies in Nuclear Physics and Related Areas, Villazzano (Italy); Gomes, P.R.S. [Universidade Federal Fluminense, Instituto de Fisica, Niteroi (Brazil); Lenske, H. [Institut fuer Theoretische Physik der Justus-Liebig-Universitaet, Giessen (Germany)
2014-11-15
We suggest new methods to extract elastic (quasi-elastic) scattering angular distribution and reaction (capture) cross sections from the experimental elastic (quasi-elastic) backscattering excitation function taken at a single angle. A novel Coulomb scattering relation between angular momentum and centrifugal energy is used. The methodology is developed for addressing complementary reaction observables, improving the description of elastic differential cross section. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Dolmashkin, A A; Dubrovskii, V A; Zabenkov, I V [V.I.Razumovsky Saratov State Medical University, Saratov (Russian Federation)
2012-05-31
The possibility is demonstrated to determine the human blood group by recording the scattering of laser radiation with the help of the digital imaging method. It is experimentally shown that the action of a standing ultrasound wave leads to acceleration of the agglutination reaction of red blood cells, to formation of larger immune complexes of red blood cells, and, as a consequence, to acceleration of their sedimentation. In the absence of agglutination of red blood cells the ultrasound does not enhance the relevant processes. This difference in the results of ultrasound action on the mixture of blood and serum allows a method of blood typing to be offered. Theoretical modelling of the technique of the practical blood typing, carried out on the basis of the elastic light scattering theory, agrees well with the experimental results, which made it possible to plan further improvement of the proposed method. The studies of specific features of sedimentation of red blood cells and their immune complexes were aimed at the optimisation of the sample preparation, i.e., at the search for such experimental conditions that provide the maximal resolution of the method and the device for registering the reaction of red blood cells agglutination. The results of the study may be used in designing the instrumentation for blood group assessment in humans.
Dolmashkin, A. A.; Dubrovskii, V. A.; Zabenkov, I. V.
2012-05-01
The possibility is demonstrated to determine the human blood group by recording the scattering of laser radiation with the help of the digital imaging method. It is experimentally shown that the action of a standing ultrasound wave leads to acceleration of the agglutination reaction of red blood cells, to formation of larger immune complexes of red blood cells, and, as a consequence, to acceleration of their sedimentation. In the absence of agglutination of red blood cells the ultrasound does not enhance the relevant processes. This difference in the results of ultrasound action on the mixture of blood and serum allows a method of blood typing to be offered. Theoretical modelling of the technique of the practical blood typing, carried out on the basis of the elastic light scattering theory, agrees well with the experimental results, which made it possible to plan further improvement of the proposed method. The studies of specific features of sedimentation of red blood cells and their immune complexes were aimed at the optimisation of the sample preparation, i.e., at the search for such experimental conditions that provide the maximal resolution of the method and the device for registering the reaction of red blood cells agglutination. The results of the study may be used in designing the instrumentation for blood group assessment in humans.
Gritzay, Olena; Kolotyi, Volodymyr; Pshenychnyi, Volodymyr; Klimova, Nataliia; Libman, Volodymyr; Venedyktov, Vitalii; Richardson, Jeffery; Sale, Kenneth
2009-08-01
The measurements of the differential elastic neutron cross-sections of carbon have been carried out at the Kyiv Research Reactor (KRR) using the neutron filter beam technique. Experimental set-up for detection of scattered neutrons has been installed at the eighth horizontal channel of the KRR. The quasi-mono-energetic neutron lines with mean energies 2, 59 and 133 keV were formed by composite filters. The measurements of the angle distribution of scattering neutrons on carbon samples were executed at angles 30°, 55°, 90°, 125° and 150° for three neutron energies. To determine the differential elastic neutron cross-section on carbon dσ/dΩ, the relative method of measurement was used. The isotope 208Pb was used as a standard. The normalization factor, which is a function of detector efficiency, thickness of the carbon samples, thickness of the Pb-208 sample, geometry, etc., for each sample and for each filter energy has been obtained through Monte Carlo calculations by means of own codes. The results of measurements of the differential elastic neutron cross sections on carbon samples at reactor neutron filtered beams with energies 2, 59, and 133 keV have been compared with the known experimental data from database EXFOR/CSISRS.
New data on the differential cross-section on dp-elastic scattering at 880 MeV obtained at Nuclotron
Directory of Open Access Journals (Sweden)
Rapatskiy V.L.
2012-12-01
Full Text Available The results on the cross-section of dp-elastic scattering reaction obtained at 880 MeV at internal target of Nuclotron are presented. The measurements have been performed using CH2 and C targets and kinematic coincidence of signals from scintillation counters. The cross-section data are compared with theoretical predictions and results of previous experiments.
Measurement of the spin rotation parameter A in the elastic pion-proton scattering at 1.43 GeV/c
Energy Technology Data Exchange (ETDEWEB)
Alekseev, I.G.; Budkovsky, P.E.; Kanavets, V.P.; Koroleva, L.I.; Morozov, B.V.; Nesterov, V.M.; Ryltsov, V.V.; Sulimov, A.D.; Svirida, D.N.; Zhurkin, V.V. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Bazhanov, N.A.; Bunyatova, E.I. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Kovalev, A.I.; Kruglov, S.P.; Novinsky, D.V.; Shchedrov, V.A.; Sumachev, V.V.; Trautman, V. Yu. [Petersburg Nuclear Physics Institute, Gatchina (Russian Federation)
2006-02-01
The ITEP-PNPI collaboration presents new results of the measurements of the spin rotation parameter A in the elastic scattering of negative pions on protons at P{sub beam}=1.43 GeV/c. The results are compared to the predictions of several partial wave analyses. The experiment was performed at the ITEP proton synchrotron, Moscow. (orig.)
Measurement of the spin rotation parameter Ain the elastic pion-proton scattering at 1.43 GeV/c
Alekseev, I. G.; Bazhanov, N. A.; Budkovsky, P. E.; Bunyatova, E. I.; Kanavets, V. P.; Kovalev, A. I.; Koroleva, L. I.; Kruglov, S. P.; Morozov, B. V.; Nesterov, V. M.; Novinsky, D. V.; Ryltsov, V. V.; Shchedrov, V. A.; Sulimov, A. D.; Sumachev, V. V.; Svirida, D. N.; Trautman, V. Yu; Zhurkin, V. V.
2006-02-01
The ITEP-PNPI collaboration presents new results of the measurements of the spin rotation parameter A in the elastic scattering of negative pions on protons at P beam = 1.43 GeV/c. The results are compared to the predictions of several partial wave analyses. The experiment was performed at the ITEP proton synchrotron, Moscow.
Measurement of the spin rotation parameter A in the elastic pion- proton scattering at 1.43 GeV/c
Alekseev, I G; Budkovsky, P E; Bunyatova, E I; Kanavets, V P; Koroleva, L I; Kovalev, A I; Kruglov, S P; Morozov, B V; Nesterov, V M; Novinsky, D V; Ryltzov, V V; Shchedrov, V A; Sulimov, A D; Sumachev, V V; Svirida, D N; Trautman, V Yu; Zhurkin, V V
2004-01-01
The ITEP-PNPI collaboration presents new results of the measurements of the spin rotation parameter A in the elastic scattering of negative pions on protons at P/sub beam/ = 1.43 GeV/c. The results are compared to the predictions of the different partial wave analyses. The experiment was performed at the ITEP proton synchrotron, Moscow.
Measurement of the Spin Rotation Parameter A in the Elastic Pion-proton Scattering at 1.43 GeV/c
Alekseev, I. G.; Bazhanov, N. A.; Budkovsky, P. E.; Bunyatova, E. I.; Kanavets, V. P.; Kovalev, A. I.; Koroleva, L. I.; Kruglov, S. P.; Morozov, B. V.; Nesterov, V. M.; Novinsky, D. V.; Ryltsov, V. V.; Shchedrov, V. A.; Sulimov, A. D.; Sumachev, V. V.
2005-01-01
The ITEP-PNPI collaboration presents new results of the measurements of the spin rotation parameter A in the elastic scattering of negative pions on protons at P_beam=1.43 GeV/c. The results are compared to the predictions of several partial wave analyses. The experiment was performed at the ITEP proton synchrotron, Moscow.
DEFF Research Database (Denmark)
Andersen, Christian Walther; Bulava, John; Hörz, Ben
2018-01-01
We present the first direct determination of meson-baryon resonance parameters from a scattering amplitude calculated using lattice QCD. In particular, we calculate the elastic I=3/2, p-wave nucleon-pion amplitude on a single ensemble of Nf=2+1 Wilson-clover fermions with mπ=280 MeV and mK=460 Me...
Helicity conservation in gauge boson scattering at high energy.
Gounaris, G J; Renard, F M
2005-04-08
We remark that the high energy gauge boson scattering processes involving two-body initial and final states satisfy certain selection rules described as helicity conservation of the gauge boson amplitudes (GBHC). These rules are valid at the Born level, as well as at the level of the leading and subleading 1-loop logarithmic corrections, in both the standard model and the minimal supersymmetric standard model (MSSM). A "fermionic equivalence" theorem is also proved, which suggests that GBHC is valid at all orders in the MSSM at sufficiently high energies, where the mass suppressed contributions are neglected.
Duran, Sean Patrick Hynes
A line of sight imaging technique was developed which utilized pulse slicing of laser pulses to shorten the duration of the parent laser pulse, thereby making time gating more effective at removing multiple scattered light. This included the development of an optical train which utilized a Kerr cell to selectively pass the initial part of the laser pulse while rejecting photons contained later within the pulse. This line of sight ballistic imaging technique was applied to image high-pressure fuel sprays injected into conditions typically encountered in a diesel combustion chamber. Varying the environmental conditions into which the fuel was injected revealed trends in spray behavior which depend on both temperature and pressure. Different fuel types were also studied in this experiment which demonstrated remarkably different shedding structures from one another. Additional experiments were performed to characterize the imaging technique at ambient conditions. The technique was modified to use two wavelengths to allow further rejection of scattered light. The roles of spatial, temporal and polarization filtration were examined by imaging an USAF 1951 line-pair target through a highly scattering field of polystyrene micro-spheres. The optical density of the scattering field was varied by both the optical path length and number densities of the spheres. The equal optical density, but with variable path length results demonstrated the need for an aggressively shorter pulse length to effectively image the distance scales typical encountered in the primary breakup regions of diesel sprays. Results indicate that the system performance improved via the use of two wavelengths. A final investigation was undertaken to image coherent light which has elastically scattered orthogonal to the direction of the laser pulse. Two wavelengths were focused into ˜150 micron sheets via a cylindrical lens and passed under the injector nozzle. The two sheets were adjustable spatially to
Low and high frequency asymptotics acoustic, electromagnetic and elastic wave scattering
Varadan, VK
2013-01-01
This volume focuses on asymptotic methods in the low and high frequency limits for the solution of scattering and propagation problems. Each chapter is pedagogical in nature, starting with the basic foundations and ending with practical applications. For example, using the Geometrical Theory of Diffraction, the canonical problem of edge diffraction is first solved and then used in solving the problem of diffraction by a finite crack. In recent times, the crack problem has been of much interest for its applications to Non-Destructive Evaluation (NDE) of flaws in structural materials.
The elastic free energy of a tandem modular protein under force.
Valle-Orero, Jessica; Eckels, Edward C; Stirnemann, Guillaume; Popa, Ionel; Berkovich, Ronen; Fernandez, Julio M
2015-05-01
Recent studies have provided a theoretical framework for including entropic elasticity in the free energy landscape of proteins under mechanical force. Accounting for entropic elasticity using polymer physics models has helped explain the hopping behavior seen in single molecule experiments in the low force regime. Here, we expand on the construction of the free energy of a single protein domain under force proposed by Berkovich et al. to provide a free energy landscape for N tandem domains along a continuous polypeptide. Calculation of the free energy of individual domains followed by their concatenation provides a continuous free energy landscape whose curvature is dominated by the worm-like chain at forces below 20 pN. We have validated our free energy model using Brownian dynamics and reproduce key features of protein folding. This free energy model can predict the effects of changes in the elastic properties of a multidomain protein as a consequence of biological modifications such as phosphorylation or the formation of disulfide bonds. This work lays the foundations for the modeling of tissue elasticity, which is largely determined by the properties of tandem polyproteins. Copyright © 2015. Published by Elsevier Inc.
High-energy vector boson scattering after the Higgs discovery
Energy Technology Data Exchange (ETDEWEB)
Kilian, Wolfgang; Sekulla, Marco [University of Siegen, Siegen (Germany); Ohl, Thorsten [Wuerzburg University, Wuerzburg (Germany); Reuter, Juergen [DESY, Hamburg (Germany)
2015-07-01
Weak vector boson scattering (VBS)at high energies will be one of the key measurements in the upcoming LHC runs. It is very sensitive to any new physics associated with electroweak symmetry breaking. But a conventional EFT analysis will fail at high energies, especially in the presence of the light 125 GeV Higgs boson. In this talk I present how to extend the EFT to a simplified model by adding additional resonances to VBS and therefore increase the energy validity of the theoretical description. Furthermore I introduce the T-matrix unitarization scheme as an extension of the K-matrix unitarization prescription. It provides an asymptotically consistent reference model, which has been matched to the low-energy effective theory of arbitrary non-perturbative and perturbative models.
Energy Technology Data Exchange (ETDEWEB)
Rudchik, Adam T., E-mail: rudchik@kinr.kiev.ua [Institute for Nuclear Research, Ukrainian Academy of Sciences, Prospect Nauki 47, 03680 Kyiv (Ukraine); Kliczewski, Stanislaw [H. Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, PL-31-342 Cracow (Poland); Chercas, Kostyantyn A. [Institute for Nuclear Research, Ukrainian Academy of Sciences, Prospect Nauki 47, 03680 Kyiv (Ukraine); Kemper, Kirby W. [Physics Department, Florida State University, Tallahassee, FL 32306-4350 (United States); Koshchy, Evgeniy I. [Kharkiv National University, pl. Svobody 4, 61077 Kharkiv (Ukraine); Rusek, Krzysztof [National Centre for Nuclear Research, ul. Hoża 69, PL-00-681 Warsaw (Poland); Heavy Ion Laboratory of Warsaw University, ul. L. Pasteura 5A, PL-02-093 Warsaw (Poland); Rudchik, Andryi A.; Mezhevych, Sergyi Yu.; Pirnak, Valeryi M. [Institute for Nuclear Research, Ukrainian Academy of Sciences, Prospect Nauki 47, 03680 Kyiv (Ukraine); Plujko, Volodymyr A. [Taras Shevchenko Kyiv National University, vul. Volodymyrs' ka 64, 01033 Kyiv (Ukraine); Ponkratenko, Oleg A. [Institute for Nuclear Research, Ukrainian Academy of Sciences, Prospect Nauki 47, 03680 Kyiv (Ukraine); Choiński, Jaroslaw [Heavy Ion Laboratory of Warsaw University, ul. L. Pasteura 5A, PL-02-093 Warsaw (Poland); Czech, Bronislaw; Siudak, Regina; Szczurek, Antoni [H. Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, PL-31-342 Cracow (Poland); Stolarz, Anna [Heavy Ion Laboratory of Warsaw University, ul. L. Pasteura 5A, PL-02-093 Warsaw (Poland); Zelinskyi, Ruslan M. [Institute for Nuclear Research, Ukrainian Academy of Sciences, Prospect Nauki 47, 03680 Kyiv (Ukraine)
2014-02-15
Inverse kinematics scattering of {sup 18}O on {sup 6}Li at E{sub lab}({sup 18}O) = 114 MeV was measured to obtain elastic and inelastic scattering cross sections. In this way cross sections for excited states in {sup 6}Li and {sup 18}O were determined. The data were analyzed within the optical model and coupled reaction channel method. The {sup 6}Li + {sup 18}O optical potential as well as the {sup 6}Li and {sup 18}O deformation parameters were deduced. Contributions of different nuclear processes to the {sup 6}Li + {sup 18}O elastic and inelastic scattering were explored. The isotopic differences between the {sup 6,7}Li + {sup 18}O and {sup 6}Li + {sup 16,18}O potential parameters were determined.
CT energy weighting in the presence of scatter and limited energy resolution
Energy Technology Data Exchange (ETDEWEB)
Schmidt, Taly Gilat [Department of Biomedical Engineering, Marquette University, Milwaukee, Wisconsin 53201 (United States)
2010-03-15
Purpose: Energy-resolved CT has the potential to improve the contrast-to-noise ratio (CNR) through optimal weighting of photons detected in energy bins. In general, optimal weighting gives higher weight to the lower energy photons that contain the most contrast information. However, low-energy photons are generally most corrupted by scatter and spectrum tailing, an effect caused by the limited energy resolution of the detector. This article first quantifies the effects of spectrum tailing on energy-resolved data, which may also be beneficial for material decomposition applications. Subsequently, the combined effects of energy weighting, spectrum tailing, and scatter are investigated through simulations. Methods: The study first investigated the effects of spectrum tailing on the estimated attenuation coefficients of homogeneous slab objects. Next, the study compared the CNR and artifact performance of images simulated with varying levels of scatter and spectrum tailing effects, and reconstructed with energy integrating, photon-counting, and two optimal linear weighting methods: Projection-based and image-based weighting. Realistic detector energy-response functions were simulated based on a previously proposed model. The energy-response functions represent the probability that a photon incident on the detector at a particular energy will be detected at a different energy. Realistic scatter was simulated with Monte Carlo methods. Results: Spectrum tailing resulted in a negative shift in the estimated attenuation coefficient of slab objects compared to an ideal detector. The magnitude of the shift varied with material composition, increased with material thickness, and decreased with photon energy. Spectrum tailing caused cupping artifacts and CT number inaccuracies in images reconstructed with optimal energy weighting, and did not impact images reconstructed with photon counting weighting. Spectrum tailing did not significantly impact the CNR in reconstructed images
Salient features of scattering amplitudes in intermediate energy nucleon-nucleus scattering
Energy Technology Data Exchange (ETDEWEB)
Susan, P.; Shastry, C.S. (Physics Department, North Eastern Hill University, Shillong-793 003 (India)); Gambhir, Y.K. (Physics Department, Indian Institute of Technology, Powai, Bombay-400 076 (India))
1994-12-01
Phenomenological relativistic optical models for scattering of nucleons from a spin-0 nucleus mainly use two different approaches. In the first, one essentially uses the Schroedinger equation incorporating appropriate relativistic kinematical terms. In the second approach, which is superior especially in reproducing spin observables, one starts with the Dirac equation and obtains an equivalent Schroedinger equation which forms a convenient basis for the calculation of experimental observables. Adopting a mathematical procedure developed earlier within the framework of potential scattering, we calculate the regionwise contribution to the reaction cross section for spin-1/2--spin-0 systems using both these types of relativistic optical models. The relative importance of different regions of intermediate energy optical potential in generating the total reaction cross section is examined using the method of regionwise absorption and it is found that reaction process is surface dominant. These findings are further elaborated by depicting the general features of [ital S] matrix and scattering amplitudes as a function of angular momentum.
Energy Technology Data Exchange (ETDEWEB)
Unamuno, S.
1965-07-01
This paper presents the results-obtained in studying the two-prong interactions observed in the Saclay 81 cm hydrogen bubble chamber exposed to the 3.0 and 4.0 GeV/c antiproton beams from CERN Proton-Synchroton. Total elastic cross-sections corresponding to both energies are given. The results are given. The results are compared with those of p-p scaterring at different energies and with those of p-p scattering. Several optical-models, from the simples one (the black disk model) to a rather elaborated, four-parameters model have been applied. These models can explain some of the experimental results but fail in predicting the angular distribution of large angle scattering. (Author)
Energy Technology Data Exchange (ETDEWEB)
Achouri, N.L
2001-09-01
This thesis describes two studies which explore the structure of proton-rich nuclei. The first of these concerned an investigation of the {beta}-delayed charged particle decay of {sup 22}Al. The experiment was carried out using the LISE3 spectrometer at GANIL and permitted the energies of the {beta}-p, {beta}-2p and {beta}-{alpha} transitions together with the corresponding branching ratios to be determined with an improved precision over earlier work. In addition the coincidences with {gamma}-rays were measured for the first time allowing the decay scheme to be reconstructed. Comparison with shell model calculations using the code OXBASH and the mirror nucleus {sup 22}F allowed the spin and parity and the mass of {sup 22}Al g.s. as well as levels in {sup 22}Mg to be deduced. The experimentally determined Gamow Teller strength was found to be in good agreement at low excitation energies with a shell model calcination employing an effective operator. The second study concerned the development of resonant elastic scattering in inverse kinematics as a spectroscopic tool. Extensive simulations were carried out to ascertain the feasibility of such experiments as well as to optimise the set-up. In the context of the later, particular attention was paid to the final resolution. Experiments subsequently undertaken at GANIL with stable and radioactive beams demonstrated that the technique will be a powerful spectroscopic tool for use with radioactive beams with characteristics similar to those that will be furnished by SPIRAL. (author)
Folding model analysis of sup 6 sup , sup 7 Li elastic scattering at 12.5-53 MeV/u
El-Azab-Farid, M
2002-01-01
sup 6 sup , sup 7 Li-nucleus double-folding optical potentials have been constructed using the JLM and a gaussian shape of the effective nucleon-nucleon interaction. Angular distributions of the differential cross sections of sup 6 sup , sup 7 Li elastic scattering from sup 1 sup 2 C, sup 2 sup 8 Si, sup 4 sup 0 Ca, sup 5 sup 8 Ni, sup 9 sup 0 Zr and sup 2 sup 0 sup 8 Pb targets at 12.5-53 MeV/u were analyzed using the derived potentials. An energy-dependent reducing renormalization coefficient was required for the real component of the JLM optical potential in order to obtain successful predictions of the observed cross sections even when the projectile density-dependence was considered. A similar behavior was found for calculations based on the density-independent gaussian version of the effective nucleon-nucleon interaction. However, no renormalization was needed when a density-dependence approximation was involved. The energy- and target mass number-dependence in the renormalization factor, real volume in...
Energy efficiency in elastic-bandwidth optical networks
DEFF Research Database (Denmark)
Vizcaino, Jorge Lopez; Ye, Yabin; Tafur Monroy, Idelfonso
2011-01-01
The forecasted growth in the Internet traffic has made the operators and industry to be concerned about the power consumption of the networks, and to become interested in alternatives to plan and operate the networks in a more energy efficient manner. The introduction of OFDM, and its property...... modulation formats offer in terms of energy efficiency....
Traffic-aware Elastic Optical Networks to leverage Energy Savings
DEFF Research Database (Denmark)
Turus, Ioan; Fagertun, Anna Manolova; Dittmann, Lars
2014-01-01
Because of the static nature of the deployed optical networks, large energy wastage is experienced today in production networks such as Telecom networks . With power-adaptive optical interfaces and suitable grooming procedures, we propose the design of more energy efficient transport networks. Op...
Ilton, Mark; Cox, Suzanne; Egelmeers, Thijs; Patek, S. N.; Crosby, Alfred J.
Impulsive biological systems - which include mantis shrimp, trap-jaw ants, and venus fly traps - can reach high speeds by using elastic elements to store and rapidly release energy. The material behavior and shape changes critical to achieving rapid energy release in these systems are largely unknown due to limitations of materials testing instruments operating at high speed and large displacement. In this work, we perform fundamental, proof-of-concept measurements on the tensile retraction of elastomers. Using high speed imaging, the kinematics of retraction are measured for elastomers with varying mechanical properties and geometry. Based on the kinematics, the rate of energy dissipation in the material is determined as a function of strain and strain-rate, along with a scaling relation which describes the dependence of maximum velocity on material properties. Understanding this scaling relation along with the material failure limits of the elastomer allows the prediction of material properties required for optimal performance. We demonstrate this concept experimentally by optimizing for maximum velocity in our synthetic model system, and achieve retraction velocities that exceed those in biological impulsive systems. This model system provides a foundation for future work connecting continuum performance to molecular architecture in impulsive systems.
Muon energy estimate through multiple scattering with the MACRO detector
Ambrosio, M; Auriemma, G; Bakari, D; Baldini, A; Barbarino, G C; Barish, B C; Battistoni, G; Becherini, Y; Bellotti, R; Bemporad, C; Bernardini, P; Bilokon, H; Bloise, C; Bower, C; Brigida, M; Bussino, S; Cafagna, F; Calicchio, M; Campana, D; Candela, A; Carboni, M; Caruso, R; Cassese, F; Cecchini, S; Cei, F; Chiarella, V; Choudhary, B C; Coutu, S; Cozzi, M; De Cataldo, G; De Deo, M; Dekhissi, H; De Marzo, C; De Mitri, I; Derkaoui, J; De Vincenzi, M; Di Credico, A; Dincecco, M; Erriquez, O; Favuzzi, C; Forti, C; Fusco, P; Giacomelli, G; Giannini, G; Giglietto, N; Giorgini, M; Grassi, M; Gray, L; Grillo, A; Guarino, F; Gustavino, C; Habig, A; Hanson, K; Heinz, R; Iarocci, E; Katsavounidis, E; Katsavounidis, I; Kearns, E; Kim, H; Kyriazopoulou, S; Lamanna, E; Lane, C; Levin, D S; Lindozzi, M; Lipari, P; Longley, N P; Longo, M J; Loparco, F; Maaroufi, F; Mancarella, G; Mandrioli, G; Margiotta, A; Marini, A; Martello, D; Marzari-Chiesa, A; Mazziotta, M N; Michael, D G; Monacelli, P; Montaruli, T; Monteno, M; Mufson, S; Musser, J; Nicolò, D; Nolty, R; Orth, C; Osteria, G; Palamara, O; Patera, V; Patrizii, L; Pazzi, R; Peck, C W; Perrone, L; Petrera, S; Pistilli, P; Popa, V; Rainó, A; Reynoldson, J; Ronga, F; Rrhioua, A; Satriano, C; Scapparone, E; Scholberg, K; Sciubba, A; Serra, P; Sioli, M; Sirri, G; Sitta, M; Spinelli, P; Spinetti, M; Spurio, M; Steinberg, R; Stone, J L; Sulak, L R; Surdo, A; Tarle, G; Tatananni, E; Togo, V; Vakili, M; Walter, C W; Webb, R
2002-01-01
Muon energy measurement represents an important issue for any experiment addressing neutrino-induced up-going muon studies. Since the neutrino oscillation probability depends on the neutrino energy, a measurement of the muon energy adds an important piece of information concerning the neutrino system. We show in this paper how the MACRO limited streamer tube system can be operated in drift mode by using the TDCs included in the QTPs, an electronics designed for magnetic monopole search. An improvement of the space resolution is obtained, through an analysis of the multiple scattering of muon tracks as they pass through our detector. This information can be used further to obtain an estimate of the energy of muons crossing the detector. Here we present the results of two dedicated tests, performed at CERN PS-T9 and SPS-X7 beam lines, to provide a full check of the electronics and to exploit the feasibility of such a multiple scattering analysis. We show that by using a neural network approach, we are able to r...
Scaling of energy amplification in the weak and strong elastic limits of viscoelastic shear flows
Hameduddin, Ismail; Zaki, Tamer; Gayme, Dennice
2015-11-01
We investigate energy amplification in viscoelastic parallel shear flows in terms of the steady-state variance maintained in the velocity and polymer stresses when either quantity is excited with white noise. We derive analytical expressions that show how this amplification scales with both Reynolds (Re) and Weissenberg (Wi) numbers. The analysis focuses on the streamwise-constant fields in the limits of high and low elasticity. By introducing stochastic forcing in both the velocity and the polymer stress dynamics, we show that at low elasticity the scaling retains a form similar to the well-known O(Re3) relationship but with an added elastic correction. At high elasticity, however, the scaling is O(Wi3) with a viscous correction. Our results demonstrate that energy amplification in a viscoelastic flow can be considerable even at low Re, correlating well with recent observations of elastic turbulence in creeping flows. We also note that forcing in the polymer stress dynamics can contribute significantly to the energy amplification.
Di Pietro, A; Fisichella, M; Alcorta, M; Borge, M J G; Davinson, T; Ferrera, F; Figuera, P; Laird, A M; Lattuada, M; Shotter, A C; Soic, N; Tengblad, O; Torresi, D; Zadro, M
2017-01-01
The excitation function of the resonant reaction 4He(9Li,α) was measured with the aim of investigating the compound nucleus 13B. These measurements were performed in inverse kinematics at center-of-mass scattering angles close to 180◦ by using a thick 4He gas target and a 9Li beam. The 13B excitation energy region explored was 14–20 MeV where 9Li–α configurations of 13B are predicted by Antysimmetrised Molecular Dynamics calculations. The measured excitation function at θcm = 180◦ shows different clear structures in a 13B excitation energy region which was experimentally unknown.
Energy Technology Data Exchange (ETDEWEB)
Bartels, J.; Borras, K.; Diehl, M.; Jung, H. (eds.)
2007-12-15
The following topics are dealt with: Lepton-proton collisions, pp and anti pp collisions, heavy ion collisions, opportunities at future colliders, cosmic rays and astropoarticle physics, theoretical developments in high-energy QCD. (HSI)
The elastic relaxation energy and equilibrium aspect ratio of self-organized pyramidal quantum dot
Energy Technology Data Exchange (ETDEWEB)
Zhou Wangmin [College of Mechanical and Electrical Engineering, Zhejiang University of Technology, Hangzhou 310032 (China)], E-mail: wangminzhou@sohu.com; Cai Chengyu [College of Mechanical and Electrical Engineering, Zhejiang University of Technology, Hangzhou 310032 (China); Yin Shuyuan [College of Science, Zhejiang University of Technology, Hangzhou 310032 (China); Wang Chongyu [Department of Physics, Tsinghua University, Beijing 100084 (China)
2008-12-30
The formation of dislocation-free three-dimensional island by heteroepitaxial growth of lattice-mismatched materials is used to produce quantum dots. The equilibrium shape of these islands results from the competition between surface and elastic energies. The system Ge/Si has been studied in detail. The elastic relaxation energy of the islands has been calculated within a continuum elasticity theory using finite element method, and the fitted function of relaxation factor with respect to aspect ratio, and functional relation between the aspect ratio and the volume of the deposited material when the epitaxial system is at equilibrium state has been obtained. The results obtained show that equilibrium aspect ration is increased with increasing QDs volume.
Hussein, Mahir; Canto, L. Felipe; Donangelo, Raul
2015-04-01
It is found that at a certain critical value of the Sommerfeld parameter the Mott oscillations usually present in the scattering of identical heavy ions, disappear and the cross section becomes quite flat. We call this effect Transverse Isotropy (TI) (L. F. Canto, R. Donangelo and M. S. Hussein, Mod. Phys. Lett. A, 16), 1027 (2001). The critical value of the Sommerfeld parameter at which TI sets in is found to be ηc =√{ 3 s + 2 } , where s is the spin of the nuclei participating in the scattering. No TI is found in the Mott scattering of identical Fermionic nuclei. The critical center of mass energy corresponding to ηc is found to be Ec = 0.40 MeV for α + α (s = 0), and 1.2 MeV for 6 Li + 6 LI (s = 1). We further found that the inclusion of the nuclear interaction induces a significant modification in the TI. This can be verified by calculating the second derivative of the cross section at θ =90° . We suggest measurements at these sub-barrier energies for the purpose of extracting useful information about the nuclear interaction between light heavy ions. Supported by CNPq, FAPESP, FAPERJ, CAPES/ITA.
Energy dependence of the optical model of neutron scattering from niobium
Energy Technology Data Exchange (ETDEWEB)
Smith, A.B.; Guenther, P.T.; Lawson, R.D.
1985-05-01
Neutron differential-elastic-scattering cross sections of niobium were measured from 1.5 to 10.0 MeV at intervals of less than or equal to200 keV below 4.0 MeV, and of approx. =500 keV from 4.0 to 10.0 MeV. Ten to more than fifty differential-cross-section values were determined at each incident energy, distributed over the angular range approx. =20 to 160/sup 0/. The observed values were interpreted in the context of the spherical optical-statistical model. It was found that the volume integral of the real potential decreased with energy whereas the integral of the imaginary part increased. The energy dependence in both cases was consistent with a linear variation. There is a dispersion relationship between the real and imaginary potentials, and when this was used, in conjunction with the experimental imaginary potential, it was possible to predict the observed energy dependence of the real potential to a good degree of accuracy, thus supporting the consistency of the data and its analysis. The real-potential well depths needed to give the correct binding energies of the 2d/sub 5/2/, 3s/sub 1/2/, 2d/sub 3/2/ and 1g/sub 7/2/ particle states and of the 1g/sub 9/2/ hole state are in reasonable agreement with those given by a linear extrapolation of the scattering potential. However, the well depths needed to give the observed binding of the 2p/sub 3/2/, 1f/sub 5/2/ and 2p/sub 1/2/ hole states are about 10% less than the extrapolated values. 40 refs., 5 figs.
Measurement of the Parity Violating Asymmetry in Elastic Electron Scattering off ^{208}Pb
Energy Technology Data Exchange (ETDEWEB)
Wexler, Jonathan [Univ. of Massachusetts, Amherst, MA (United States)
2014-09-01
The Lead Radius Experiment (PREX) was carried out in order to provide a model-independent measurement of the RMS radius √<$2\\atop{n}$> of the neutron distribution in the^{ 208}Pb nucleus. The parity-violating scattering asymmetry for longitudinally polarized 1.06 GeV electrons from an unpolarized 208Pb target was measured at Q2 = 0.00880 GeV2. This measurement was performed by the PREX collaboration in Hall A at Jefferson Laboratory in Newport News, VA, between March and June, 2010. The electron detectors used in this measurement were designed and fabricated by University of Massachusetts-Amherst and Smith College. The resulting parity-violating asymmetry was measured as APV = 656±60(stat.)±14(sys.) ppb. This asymmetry extrapolates to a difference in radii between the nuclear neutron and proton distributions of √<$2\\atop{n}$>-√<$2\\atop{p}$>=0.33$+0.16\\atop{-0.18}$ fm.
Energy Technology Data Exchange (ETDEWEB)
Yokosawa, A.
1985-01-01
We review experimental results concerning polarization phenomena in nucleon-nucleon scattering in which both the elastic scattering and hadron-production reaction are included. We also present summary of S = 0 dibaryon resonances and candidates by reviewing experimental data in the nucleon-nucleon system, ..gamma..d channel, ..pi..d elastic scattering, pp ..-->.. ..pi..d channel, deuteron break-up reactions, and narrow structures in missing-mass spectra. 93 refs., 26 figs.
Low-energy electron scattering from molecules, biomolecules and surfaces
Carsky, Petr
2011-01-01
Since the turn of the 21st century, the field of electron molecule collisions has undergone a renaissance. The importance of such collisions in applications from radiation chemistry to astrochemistry has flowered, and their role in industrial processes such as plasma technology and lighting are vital to the advancement of next generation devices. Furthermore, the development of the scanning tunneling microscope highlights the role of such collisions in the condensed phase, in surface processing, and in the development of nanotechnology.Low-Energy Electron Scattering from Molecules, Biomolecule
Brandow, Heather P.; Lee, Vincent
2017-07-01
Scattering and Diffraction of elastic in-plane P- and SV- waves by a surface topography such as an elastic canyon at the surface of a half-space is a classical problem which has been studied by earthquake engineers and strong-motion seismologists for over forty years. The case of out-of-plane SH waves on the same elastic canyon that is semi-circular in shape on the half-space surface is the first such problem that was solved by analytic closed form solutions over forty years ago by Trifunac. The corresponding case of in-plane P- and SV-waves on the same circular canyon is a much more complicated problem because, the in-plane P- and SV- scattered waves have different wave speeds and together they must have zero normal and shear stresses at the half-space surface. It is not until recently in 2014 that analytic solution for such problem is found by the author in the work of Lee and Liu. This paper uses the technique of Lee and Liu of defining these stress-free scattered waves to solve the problem of the scattered and diffraction of these in-plane waves on an almost-circular surface canyon that is arbitrary in shape.
Trzcinski, A; Müller, W F J; Trautmann, W; Zwieglinski, B; Auger, G; Bacri, C O; Begemann-Blaich, M L; Bellaize, N; Bittiger, R; Bocage, F; Borderie, B; Bougault, R; Bouriquet, B; Buchet, P; Charvet, J L; Chbihi, A; Dayras, R; Doré, D; Durand, D; Frankland, J D; Galíchet, E; Gourio, D; Guinet, D; Hudan, S; Hurst, B; Lautesse, P; Lavaud, F; Laville, J L; Leduc, C; Lefèvre, A; Legrain, R; López, O; Lynen, U; Nalpas, L; Orth, H; Plagnol, E; Rosato, E; Saija, A; Schwarz, C; Sfienti, C; Steckmeyer, J C; Tabacaru, G; Tamain, B; Turzó, K; Vient, E; Vigilante, M; Volant, C
2003-01-01
An efficient method of energy scale calibration for the CsI(Tl) modules of the INDRA multidetector (rings 6-12) using elastic and inelastic sup 1 sup 2 C+ sup 1 H scattering at E( sup 1 sup 2 C)=30 MeV per nucleon is presented. Background-free spectra for the binary channels are generated by requiring the coincident detection of the light and heavy ejectiles. The gain parameter of the calibration curve is obtained by fitting the proton total charge spectra to the spectra predicted with Monte-Carlo simulations using tabulated cross section data. The method has been applied in multifragmentation experiments with INDRA at GSI.
Jeong, M K; Hwang, C; Nam, H; Cho, Y S; Kang, B Y; Cho, E C
2017-02-01
The purpose of this study was to determine how the energies supplied from a cosmetic vibrator are deeply or far transferred into organs and tissues, and how these depths or distances are influenced by tissue elasticity. External vibration energy was applied to model skin surfaces through a facial cleansing vibrator, and we measured a distance- and depth-dependent energy that was transferred to model skin matrices. As model skin matrices, we synthesized hard and soft poly(dimethylsiloxane) (PDMS) gels, as well as hydrogels with a modulus of 2.63 MPa, 0.33 MPa and 21 kPa, respectively, mostly representing those of skin and other organs. The transfer of vibration energy was measured either by increasing the separation distances or by increasing the depth from the vibrator. The energies were transmitted deeper into the hard PDMS than into the soft PDMS and hydrogel matrices. This finding implies that the vibration forces influence a larger area of the gel matrices when the gels are more elastic (or rigid). There were no appreciable differences between the soft PDMS and hydrogel matrices. However, the absorbed energies were more concentrated in the area closest to the vibrator with decreasing elasticity of the matrix. Softer materials absorbed most of the supplied energy around the point of the vibrator. In contrast, harder materials scattered the external energy over a broad area. The current results are the first report in estimating how the external energy is deeply or distantly transferred into a model skins depending on the elastic moduli of the models skins. In doing so, the results would be potentially useful in predicting the health of cells, tissues and organs exposed to various stimuli. © 2016 Society of Cosmetic Scientists and the Société Française de Cosmétologie.
Muscle-tendon interaction and elastic energy usage in human walking
DEFF Research Database (Denmark)
Ishikawa, Masaki; Komi, Paavo V.; Grey, Michael James
2005-01-01
The present study was designed to explore how the interaction between the fascicles and tendinous tissues is involved in storage and utilization of elastic energy during human walking. Eight male subjects walked with a natural cadence (1.4 +/- 0.1 m/s) on a 10-m-long force plate system. In vivo...
Water holding as determinant for the elastically stored energy in protein-based gels
Pouvreau, L.A.M.; Wijlen, van Emke; Klok, Jan; Urbonaite, V.; Munialo, C.D.; Jongh, de H.H.J.
2016-01-01
To evaluate the importance of the water holding capacity for the elastically stored energy of protein gels, a range of gels were created from proteins from different origin (plant: pea and soy proteins, and animal: whey, blood plasma, egg white proteins, and ovalbumin) varying in network morphology
Energy Technology Data Exchange (ETDEWEB)
Schultz, D.R.; Krstic, P.S. [Oak Ridge National Lab. TN (United States). Physics Div.
1997-01-01
Due to the present interest in modeling and diagnosing the edge and divertor plasma regions in magnetically confined fusion devices, we have sought to provide new calculations regarding the elastic, excitation, ionization, and charge transfer cross sections in collisions among relevant ions, neutrals, and isotopes in the low-to intermediate-energy regime. We summarize here some of our recent work. (author)
Studying conformally flat spacetimes with an elastic stress energy tensor using 1 + 3 formalism
Brito, I.; Ramos, M. P. Machado
2015-12-01
Conformally flat spacetimes with an elastic stress-energy tensor having diagonal trace-free anisotropic pressure are investigated using 1 + 3 formalism. The 1 + 3 Bianchi and Jacobi identities and Einstein field equations are written for a particular case with a conformal factor dependent on only one spatial coordinate. Solutions with non zero anisotropic pressure are obtained.
Energy Technology Data Exchange (ETDEWEB)
Tattersall, Wade [Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200 (Australia); Centre for Antimatter-Matter Studies, School of Engineering and Physical Sciences, James Cook University, Townsville, 4810 Queensland (Australia); Chiari, Luca [Centre for Antimatter-Matter Studies, School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide 5001, South Australia (Australia); Machacek, J. R.; Anderson, Emma; Sullivan, James P. [Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200 (Australia); White, Ron D. [Centre for Antimatter-Matter Studies, School of Engineering and Physical Sciences, James Cook University, Townsville, 4810 Queensland (Australia); Brunger, M. J. [Centre for Antimatter-Matter Studies, School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide 5001, South Australia (Australia); Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia); Buckman, Stephen J. [Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200 (Australia); Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia); Garcia, Gustavo [Instituto de Fısica Fundamental, Consejo Superior de Investigationes Cientıficas (CSIC), Serrano 113-bis, E-28006 Madrid (Spain); Blanco, Francisco [Departamento de Fısica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, E-28040 Madrid (Spain)
2014-01-28
Utilising a high-resolution, trap-based positron beam, we have measured both elastic and inelastic scattering of positrons from water vapour. The measurements comprise differential elastic, total elastic, and total inelastic (not including positronium formation) absolute cross sections. The energy range investigated is from 1 eV to 60 eV. Comparison with theory is made with both R-Matrix and distorted wave calculations, and with our own application of the Independent Atom Model for positron interactions.
Directory of Open Access Journals (Sweden)
Giovanni Carlotti
2018-01-01
Full Text Available There is currently a renewed interest in the development of experimental methods to achieve the elastic characterization of thin films, multilayers and acoustic resonators operating in the GHz range of frequencies. The potentialities of surface Brillouin light scattering (surf-BLS for this aim are reviewed in this paper, addressing the various situations that may occur for the different types of structures. In particular, the experimental methodology and the amount of information that can be obtained depending on the transparency or opacity of the film material, as well as on the ratio between the film thickness and the light wavelength, are discussed. A generalization to the case of multilayered samples is also provided, together with an outlook on the capability of the recently developed micro-focused scanning version of the surf-BLS technique, which opens new opportunities for the imaging of the spatial profile of the acoustic field in acoustic resonators and in artificially patterned metamaterials, such as phononic crystals.
Wang, Ji; Yang, Jiashi; Li, Jiangyu
2007-03-01
Energy trapping has important applications in the design of thickness-shear resonators. Considerable efforts have been made for the effective utilization and improvement of energy trapping with variations of plate configurations, such as adding electrodes and contouring. As a new approach in seeking improved energy trapping feature, we analyze thickness-shear vibrations in an elastic plate with functionally graded material (FGM) of in-plane variation of mechanical properties, such as elastic constants and density. A simple and general equation governing the thickness-shear modes is derived from a variational analysis. A plate with piecewise constant material properties is analyzed as an example. It is shown that such a plate can support thickness-shear vibration modes with obvious energy trapping. Bechmann's number for the existence of only one trapped mode also can be determined accordingly.
A Hamiltonian theory for an elastic earth - Canonical variables and kinetic energy
Getino, Juan; Ferrandiz, Jose M.
1990-09-01
This paper describes the first part of a project dedicated to elaborating a Hamiltonian theory for the rotational motion of a deformable earth. Here only the perturbation due to the deformation of the elastic mantle by tidal body force is studied. Two canonical systems of variables are developed, known as elastic variables of Euler and Andoyer, respectively. Next, they are used to obtain the canonical expression of rotational kinetic energy, which is valid for any earth model satisfying hypotheses as general as those established here.
Energy Technology Data Exchange (ETDEWEB)
Alekseev, I.G.; Budkovsky, P.E.; Kanavets, V.P.; Koroleva, L.I.; Morozov, B.V.; Nesterov, V.M.; Ryltsov, V.V.; Sulimov, A.D.; Svirida, D.N.; Zhurkin, V.V. [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Bazhanov, N.A.; Bunyatova, E.I. [Joint Inst. for Nuclear Research, Dubna (Russian Federation); Beloglazov, Yu.A.; Kovalev, A.I.; Kruglov, S.P.; Novinsky, D.V.; Shchedrov, V.A.; Sumachev, V.V.; Trautman, V.Yu. [St. Petersburg Inst. of Nuclear Physics, Gatchina (Russian Federation)
2001-09-01
The spin rotation parameters A and R were measured for the elastic pion-proton scattering by the PNPI-ITEP collaboration in the D{sub 13}(1700) resonance region. The main goal of the experimental program is to resolve the current partial-wave analyses (PWA) uncertainties. Simultaneously with A and R the polarization parameter P was measured with the purpose to improve the experimental database and estimate systematic errors. The constraint which demands a smooth energy dependence of all {pi}{sup -}p transverse amplitude zeros in the complex plane together with the new experimental data on A parameter can lead to the conclusion that the Barrelet branch of ''zero trajectories'' is chosen improperly in PWA of the Carnegie-Mellon-Lawrence-Berkeley-Laboratory groups at the range of the pion beam momentum near 1.0 GeV/c. The setup included a longitudinally polarized proton target with superconductive magnet, multiwire spark chambers and carbon polarimeter with thick filter. The experiment was performed at the ITEP proton synchrotron, Moscow. (orig.)
Alekseev, I G; Beloglasov, Yu A; Budkovsky, P E; Bunyatova, E I; Kanavets, V P; Kovalev, A I; Koroleva, L I; Kruglov, S P; Morozov, B V; Nesterov, V M; Novinsky, D V; Ryltzov, V V; Shchedrov, V A; Sulimov, A D; Sumachev, Yu V; Svirida, D N; Trautman, V Yu; Zhurkin, V V
2001-01-01
The spin rotation parameters A and R were measured for the elastic pion-proton scattering by the PNPI-ITEP collaboration in the D/sub 13 /(1700) resonance region. The main goal of the experimental program is to resolve the current partial-wave analyses (PWA) uncertainties. Simultaneously with A and R the polarization parameter P was measured with the purpose to improve the experimental database and estimate systematic errors. The constraint which demands a smooth energy dependence of all pi /sup -/p transverse amplitude zeros in the complex plane together with the new experimental data on the A parameter can lead to the conclusion that the Barrelet branch of "zero trajectories" is chosen improperly in PWA of the Carnegie- Mellon-Lawrence-Berkeley-Laboratory groups at the range of the pion beam momentum near 1.0 GeV/c. The setup included a longitudinally polarized proton target with superconductive magnet, multiwire spark chambers and carbon polarimeter with thick filter. The experiment was performed at the IT...
Elastic energy of curvature-driven bump formation on red blood cell membrane.
Waugh, R.E.
1996-01-01
Model calculations were performed to explore quantitative aspects of the discocyte-echinocyte shape transformation in red blood cells. The shape transformation was assumed to be driven by changes in the preferred curvature of the membrane bilayer and opposed by the elastic shear rigidity of the membrane skeleton. The energy required for echinocyte bump formation was calculated for a range of bump shapes for different preferred curvatures. Energy minima corresponding to nonzero bump heights we...
Frictional and elastic energy in gecko adhesive detachment
Gravish, Nick; Wilkinson, Matt; Autumn, Kellar
2007-01-01
Geckos use millions of adhesive setae on their toes to climb vertical surfaces at speeds of over 1 m s−1. Climbing presents a significant challenge for an adhesive since it requires both strong attachment and easy, rapid removal. Conventional pressure-sensitive adhesives are either strong and difficult to remove (e.g. duct tape) or weak and easy to remove (e.g. sticky notes). We discovered that the energy required to detach adhering tokay gecko setae (Wd) is modulated by the angle (θ) of a li...
Energy storage by passive elastic structures in the mantle of sepia officinalis.
Curtin, N A; Woledge, R C; Bone, Q
2000-03-01
The passive elastic properties of the mantle of the cuttlefish Sepia officinalis have been characterized in experiments on intact mantle and on pieces cut from the mantle. The mantle was found to be very compliant over a wide range of circumferential strains, corresponding to a change in mantle circumferential strain of 0.45. Beyond this range of strain, the mantle was much stiffer, in both the circumferential direction, 0.542+/-0.025 MPa (mean +/- s.e.m., N=51) and through the thickness of the mantle wall, 0.152+/-0.041 MPa (N=11). Almost 80 % of the work done on the tissue during compression in the circumferential direction was recovered during elastic recoil of the tissue; this elastic work could contribute to refilling the mantle after a jet. Our estimates of the work done during a cycle of jetting and refilling show that such elastic work is small (approximately 1 %) compared with the contractile work done by the circular muscle fibres. However, although the elastic work is almost negligible in the overall energy budget, it is probably sufficient to power refilling of the mantle.
Sumachev, V. V.; Beloglazov, Yu. A.; Filimonov, E. A.; Kovalev, A. I.; Kozlenko, N. G.; Kruglov, S. P.; Kulbardis, A. A.; Lopatin, I. V.; Novinsky, D. V.; Shchedrov, V. A.; Trautman, V. Yu.; Alekseev, I. G.; Budkovsky, P. E.; Kanavets, V. P.; Koroleva, L. I.; Morozov, B. V.; Nesterov, V. M.; Ryltsov, V. V.; Sulimov, A. D.; Svirida, D. N.; Bazhanov, N. A.; Bunyatova, E. I.
2008-10-01
The existing models of baryons usually predict considerably more resonance (three or more in number) than it was found by investigation of elastic pion-nucleon scattering. This disagreement invites further investigation of the pion-nucleon interaction and among other things the measurement of spin rotation parameters A and R in the elastic pion-nucleon scattering. Recent experiments of the PNPI and PNPI-ITEP collaborations resolved a part of twofold ambiguities of the existing partial wave analyses (PWA). These results were used in the last PWA of the George Washington University group SP06. The proposal for the additional spin rotation parameters A and R measurement in the resonance region is motivated. Such additional measurements are necessary to resolve remaining twofold ambiguities of the existing PWAs.
Results for the Asymmetry Measurement in Elastic Pion-Proton Scattering at 1.78 and 2.07GeV/c
Alekseev, I. G.; Budkovsky, P. E.; Kanavets, V. P.; Koroleva, L. I.; Morozov, B. V.; Nesterov, V. M.; Ryltsov, V. V.; Sulimov, A. D.; Svirida, D. N.; Zhurkin, V. V.; Beloglazov, Y. A.; Filimonov, E. A.; Kovalev, A. I.; Kruglov, S. P.; Novinsky, D. V.; Shchedrov, V. A.; Sumachev, V. V.; Trautman, V. Y.; Bazhanov, N. A.; Bunyatova, E. I.
2005-08-01
New experimental results from the ITEP-PNPI collaboration are presented on the asymmetry in backward elastic scattering of negative pions on polarized protons in the resonance region. The data were obtained in the angular region (150° - 170°) c.m. at initial momenta 1.78 and 2.07 GeV/c. The results are compared to the predictions of partial wave analyses. The measurement was done at the ITEP accelerator.
Directory of Open Access Journals (Sweden)
Philipp Beckerle
2017-09-01
Full Text Available Variable elastic actuators are very promising for applications in physical human–robot interaction. Besides enabling human safety, such actuators can support energy efficiency, especially if the natural behavior of the system is exploited. In this paper, the power and energy consumption of variable stiffness actuators with serial elasticity is investigated analytically and experimentally. Besides the fundamental mechanics, the influence of friction and electrical losses is discussed. A simple but effective stiffness control method is used to exploit the corresponding knowledge of natural dynamics by tuning the system to antiresonance operation. Despite nonlinear friction effects and additional electrical dynamics, the consideration of the ideal mechanical dynamics is completely sufficient for stiffness control. Simulations and experiments show that this yields a distinct reduction in power and energy consumption, which underlines the suitability of the control strategy.
Energy Technology Data Exchange (ETDEWEB)
Patzak, W.
1985-06-01
This is a further contribution to the discussion of energy source substitution. The limiting conditions of an industrial plant, whose relationships had been generally discussed earlier, are now being quantified. The structure of energy production costs and their sensitivity to cost factor variation are investigated and graphically presented. The order of precedence for the influencing factors is established with the aid of elasticity or reactivity of energy costs; their significance for the total energy costs is shown. This leads to suggestions for effective cost reductions.