Elastic scattering phenomenology
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.)
Elastic scattering and total reaction cross sections with low-energy light radioactive ion beams.
Guimarães Valdir
2011-10-01
Full Text Available Elastic scattering experiments have being performed with low-energy radioactive ion beams produced by the RIBRAS facility in Sao Paulo, Brazil. Here I present the results for elastic scattering of 6He on several targets and light beams on 12C target. Special emphasis is given to the analysis of experiments were angular distributions for the elastic scattering of beryllium isotopes projectiles, 7Be, 9Be and 10Be, on a light target 12C were obtained. These elastic scattering angular distributions have been analysed in terms of optical model using the double-folding Sao Paulo potential. From this analysis, the total reaction cross section were also deduced and compared to the total reaction cross sections for many other light projectiles on 12C target. The comparison was made in terms of Universal Function reduction method.
Dremin, I M
2012-01-01
When colliding, the high energy hadrons can either produce new particles or scatter elastically without change of their quantum num- bers and other particles produced. Namely elastic scattering of hadrons is considered in this review paper. Even though the inelastic processes dominate at high energies, the elastic scattering constitutes the notice- able part of the total cross section ranging between 18 and 25% with some increase at higher energies. The scattering proceeds mostly at small angles and reveals peculiar dependences at larger angles disclos- ing the geometrical structure of the colliding particles and di?erent dynamical mechanisms. The fast decreasing Gaussian peak at small angles is followed by the exponential (Orear) regime with some shoul- ders and dips and then by the power-like decrease. Results of various theoretical approaches are compared with exper- imental data. Phenomenological models pretending to describe this process are reviewed. The unitarity condition requires the exponen- tial re...
Dremin, I. M.
2013-01-01
Colliding high-energy hadrons either produce new particles or scatter elastically with their quantum numbers conserved and no other particles produced. We consider the latter case here. Although inelastic processes dominate at high energies, elastic scattering contributes considerably (18-25%) to the total cross section. Its share first decreases and then increases at higher energies. Small-angle scattering prevails at all energies. Some characteristic features can be seen that provide information on the geometrical structure of the colliding particles and the relevant dynamical mechanisms. The steep Gaussian peak at small angles is followed by the exponential (Orear) regime with some shoulders and dips, and then by a power-law decrease. Results from various theoretical approaches are compared with experimental data. Phenomenological models claiming to describe this process are reviewed. The unitarity condition predicts an exponential fall for the differential cross section with an additional substructure to occur exactly between the low momentum transfer diffraction cone and a power-law, hard parton scattering regime under high momentum transfer. Data on the interference of the Coulomb and nuclear parts of amplitudes at extremely small angles provide the value of the real part of the forward scattering amplitude. The real part of the elastic scattering amplitude and the contribution of inelastic processes to the imaginary part of this amplitude (the so-called overlap function) are also discussed. Problems related to the scaling behavior of the differential cross section are considered. The power-law regime at highest momentum transfer is briefly described.
Elastic scattering in geometrical model
Plebaniak, Zbigniew; Wibig, Tadeusz
2016-10-01
The experimental data on proton-proton elastic and inelastic scattering emerging from the measurements at the Large Hadron Collider, calls for an efficient model to fit the data. We have examined the optical, geometrical picture and we have found the simplest, linear dependence of this model parameters on the logarithm of the interaction energy with the significant change of the respective slopes at one point corresponding to the energy of about 300 GeV. The logarithmic dependence observed at high energies allows one to extrapolate the proton-proton elastic, total (and inelastic) cross sections to ultra high energies seen in cosmic rays events which makes a solid justification of the extrapolation to very high energy domain of cosmic rays and could help us to interpret the data from an astrophysical and a high energy physics point of view.
Study of the {sup 6}He+{sup 9}Be elastic scattering at low energies
Pires, K.C.C.; Lichtenthaeler, R.; Lepine-Szily, A.; Guimaraes, V.; Faria, P.N.; Crema, E.; Barioni, A.; Mendes Junior, V.; Morcelle, V.; Morais, M.C.; Pampa Condori, R.; Huiza, J.F.P. [Universidade de Sao Paulo (IF/USP), SP (Brazil). lnst. de Fisica. Dept. de Fisica Nuclear; Moro, A.M.; Rodriguez-Gallardo, M. [University of Seville (Sri Lanka). Dept. of Atomic, Molecular and Nuclear Physics; Assuncao, M. [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil); Shorto, J.M.B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP) Sao Paulo, SP (Brazil); Mukherjee, S. [University of Baroda, Vadodara (India). Faculty of Science. Dept. of Physics
2011-07-01
New data of the {sup 6}He+{sup 9}Be elastic scattering at E{sub lab}=16.2MeV and 21.3MeV have been measured. A very large reaction cross section has been previously observed in the collision of {sup 6}He with medium and heavy mass targets, which has been attributed to high 6He breakup probability in the strong Coulomb + nuclear interaction. More recently the importance of neutron transfer reactions between projectile and target has been pointed out. The main goal of the present experiment is to investigate the halo nature of the {sup 6}He nucleus by its interaction with a light target. The experiment has been performed at the Pelletron Laboratory of the Institute of Physics of the University of Sao Paulo, Brazil, using the RIBRAS facility. The RIBRAS system consists of two superconducting solenoids used to focus and select the radioactive secondary beam. The {sup 6}He secondary beam was produced by the {sup 9}Be({sup 7}Li,{sup 6}He) reaction with a {sup 7}Li primary beam of 200nA. The detection system consisted of four {Delta}E-E Silicon telescopes, with 20{mu}m and 1000{mu}m thickness respectively, which allow to separate the {sup 6}He particles from the {sup 7}Li, {sup 4}He, and light particles contaminants. The {sup 6}He+{sup 9}Be angular distributions have been analyzed with optical model, Coupled Channels (CC) and Continuum Discretized Coupled Channels (CDCC) calculations. The comparison between the experimental data and the CDCC calculations allow us to conclude that the breakup of the projectile via the coupling to the {sup 6}He 2{sup +} resonance is very important to reproduce the data. In addition, we studied the effect of excitation of the {sup 9}Be target explicitly by a CC calculation, using a collective model to describe the excitation of the first low lying states of {sup 9}Be. We found that the coupling to these states significantly affects the elastic scattering. From this analysis it was possible to obtain the total reaction cross section which was
Elastic Scattering Properties of Ultracold Strontium Atoms
张计才; 朱遵略; 刘玉芳; 孙金锋
2011-01-01
We investigate the elastic scattering properties of strontium atoms at ultracold temperatures.The scattering parameters,such as s-wave scattering lengths,effective ranges and p-wave scattering lengths,are calculated for all stable isotope combinations of Sr atoms by the quantal method and semiclassical method,respectively.Good agreements are obtained.The scattering parameters are very sensitive to small changes of the reduced mass.Due to the repulsive interisotope and intraisotope s-wave scattering length and large elastic cross sections,84Sr-86Srmixture is a good candidate to realize Bose-Bose quantum degenerate atomic gases.%We investigate the elastic scattering properties of strontium atoms at ultracold temperatures. The scattering parameters, such as s-wave scattering lengths, effective ranges and p-wave scattering lengths, are calculated for all stable isotope combinations of Sr atoms by the quantal method and semiclassical method, respectively. Good agreements are obtained. The scattering parameters are very sensitive to small changes of the reduced mass. Due to the repulsive interisotope and intraisotope s-wave scattering length and large elastic cross sections, MSr-s(iSr mixture is a good candidate to realize Bose-Bose quantum degenerate atomic gases.
Spin observables in elastic proton scattering
Aas, B.; Hynes, M. V.; Picklesimer, A.; Tandy, P. C.; Thaler, R. M.
1985-07-01
The use of alternative representations of spin observables for elastic scattering is investigated within the context of comparing relativistic and nonrelativistic approaches. The results of calculations of the observables Ay and Q together with the alternatives S and β are presented for elastic scattering of 650, 500, and 318 MeV protons from 40Ca. At the lower energy, the spin observables S and β appear to be particularly sensitive to the nature of the theoretical treatment. The implications of theoretical input uncertainties for the possibility of extracting nuclear target information in the relativistic approach are considered.
Spin observables in elastic proton scattering
Aas, B.; Hynes, M.V.; Picklesimer, A.; Tandy, P.C.; Thaler, R.M.
1985-07-01
The use of alternative representations of spin observables for elastic scattering is investigated within the context of comparing relativistic and nonrelativistic approaches. The results of calculations of the observables A/sub y/ and Q together with the alternatives S and ..beta.. are presented for elastic scattering of 650, 500, and 318 MeV protons from /sup 40/Ca. At the lower energy, the spin observables S and ..beta.. appear to be particularly sensitive to the nature of the theoretical treatment. The implications of theoretical input uncertainties for the possibility of extracting nuclear target information in the relativistic approach are considered.
Relativistic analysis of proton elastic scattering
El Nohy, N. A.; El-Hammamy, M. N.; Yoseph, S. I.; Abdel-Moneim, A. M.
2015-04-01
The Dirac equation as the relevant wave equation, is used in modified DWUCK4 program to calculate the elastic scattering cross section throughout the energy range suitable for relativistic treatment of proton elastic scattering by nuclei 40Ca, 58Ni, 90Zr and 208Pb. A good fit to the experimental data is presented. The real and imaginary potentials are well determined and behave regularly with energy. The behaviour of the real central effective potential shows the development of a "wine-bottle" shape in the transition energy region and the persistence of a small attractive potential in the nuclear surface region, even at 800 MeV.
Full Elasticity Tensor from Thermal Diffuse Scattering
Wehinger, Björn; Mirone, Alessandro; Krisch, Michael; Bosak, Alexeï
2017-01-01
We present a method for the precise determination of the full elasticity tensor from a single crystal diffraction experiment using monochromatic x rays. For the two benchmark systems calcite and magnesium oxide, we show that the measurement of thermal diffuse scattering in the proximity of Bragg reflections provides accurate values of the complete set of elastic constants. This approach allows for a reliable and model-free determination of the elastic properties and can be performed together with crystal structure investigation in the same experiment.
Elastic proton-proton scattering at RHIC
Yip, K.
2011-09-03
Here we describe elastic proton+proton (p+p) scattering measurements at RHIC in p+p collisions with a special optics run of {beta}* {approx} 21 m at STAR, at the center-of-mass energy {radical}s = 200 GeV during the last week of the RHIC 2009 run. We present preliminary results of single and double spin asymmetries.
On the Elastic Scattering of Heavy Nuclei
McIntosh, J. S.; Park, S. C.; Turner, J. E.
1960-01-01
A program is presented for determining the differential cross-section for the elastic scattering of heavy nuclei. It utilizes the unitary property of the S-matrix and a less drastic L-dependence of the absorption than the sharp cut-off model of Blair. it is shown that experimental data can be fitted quite well. (auth)
A theoretical study of elastic X-ray scattering
Stewart, Robert F.; Feil, Dirk
1980-01-01
Bragg X-ray scattering intensities are defined as scattering by the thermodynamic average electron-charge density. Purely elastic, kinematic X-ray scattering by a target in thermal equilibrium is always larger than Bragg scattering. At low temperatures, the elastic scattering becomes Bragg
Differential elastic electron scattering by pentane
Fedus, Kamil; Navarro, C.; Hargreaves, L. R.; Khakoo, M. A.; Barbosa, Alessandra Souza; Bettega, M. H. F.
2015-04-01
We report measurements and calculations of the differential cross sections for elastic scattering of low-energy electrons by pentane, C5H12 . The incident energies measured are at 1, 1.5, 2, 3, 5, 10, 15, 20, 30, 50, and 100 eV, and the calculations covered energies up to 100 eV. The range of experimental scattering angles is from 5° to 130°. We compare our experimental and theoretical values to each other and to available experimental and theoretical data for linear n -alkanes.
Measurement of elastic scattering with ALFA
Jakobsen, S; The ATLAS collaboration
2012-01-01
The principal of ALFA is presented and then a detailed description of the detector, installation, triggering and beam based alignment. All this was needed in 2011 before the special optics runs with beta* = 90 m which was used for measuring elastic scattering. The first analysis steps of seeing tack patterns, making a global alignment of the detectors and finding correlations are presented. The plans for upcoming runs in 2012 are briefly discussed.
Positron elastic scattering from alkaline earth targets
Poveda, Luis A.; Assafrão, Denise; Mohallem, José R.
2016-07-01
A previously reported model potential approach [Poveda et al., Phys. Rev. A 87, 052702 (2013)] was extended to study low energy positron elastic scattering from beryllium and magnesium. The cross sections were computed for energies ranging from 10-5 eV up to well above the positronium formation threshold. The present results are in good agreement with previous reports, including the prediction of a p-wave resonance in the cross section for magnesium. The emergence of this shape resonance is connected to a trend observed in the evolution of the partial wave cross section in going from Be to Mg target. This trend lead us to speculate that a sharp d-wave resonance should be observed in positron elastic scattering from calcium. The positron-target binding energies are investigated in detail, both using the scattering information and by direct computation of the bound state energies using the model potentials. Contribution to the Topical Issue "Advances in Positron and Electron Scattering", edited by Paulo Limao-Vieira, Gustavo Garcia, E. Krishnakumar, James Sullivan, Hajime Tanuma and Zoran Petrovic.Supplementary material in the form of one pdf file available from the Journal web page at http://dx.doi.org/10.1140/epjd/e2016-70120-y
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)
Elastic and diffractive scattering at D0
Edwards, Tamsin; /Manchester U.
2004-04-01
The first search for diffractively produced Z bosons in the muon decay channel is presented, using a data set collected by the D0 detector at the Fermilab Tevatron at {radical}s = 1.96 TeV between April and September 2003, corresponding to an integrated luminosity of approximately 110 pb{sup -1}. The first dN/d|t| distribution for proton-antiproton elastic scattering at this c.o.m. energy is also presented, using data collected by the D0 Forward Proton Detector between January and May 2002. The measured slope is reproduced by theoretical predictions.
Elastic scattering tracking at the Tevatron
Avila, C. [Cornell Univ., Ithaca, NY (United States); Baker, W. [Fermi National Accelerator Laboratory, Batavia, IL (United States); DeSalvo, R. [European Organization for Nuclear Research, Geneva (Switzerland); Eartly, D. [Fermi National Accelerator Laboratory, Batavia, IL (United States); Guss, C. [Cornell Univ., Ithaca, NY (United States); Jostlein, H. [Fermi National Accelerator Laboratory, Batavia, IL (United States); Lundin, M. [Universite Louis Pasteur and CRN, Strasbourg (France); Mondardini, M.R. [Cornell Univ., Ithaca, NY (United States); Orear, J. [Cornell Univ., Ithaca, NY (United States)
1995-06-01
Tracks have been observed for the first time with a new scintillating fibers and image intensifiers based detector mounted directly inside the vacuum of the Tevatron collider to study pp{sup -} small angle scattering at {radical}(s)=1.8 TeV. This detector was conceived and developed at CERN and built at DEP for elastic scattering measurements at the Tevatron and future colliders. Two pairs of such detectors, symmetric in the vertical plane, will be located along the beam pipe at either side from the interaction point E0 in the Tevatron. The first detector has been recently installed by the E811 collaboration and is being tested with beam halo. Another one is being tested in a cosmic ray setup. Preliminary results are presented from both configurations and agree with preliminary tests performed at CERN/PS. (orig.).
Inverse obstacle scattering for elastic waves
Li, Peijun; Wang, Yuliang; Wang, Zewen; Zhao, Yue
2016-11-01
Consider the scattering of a time-harmonic plane wave by a rigid obstacle which is embedded in an open space filled with a homogeneous and isotropic elastic medium. An exact transparent boundary condition is introduced to reduce the scattering problem into a boundary value problem in a bounded domain. Given the incident field, the direct problem is to determine the displacement of the wave field from the known obstacle; the inverse problem is to determine the obstacle’s surface from the measurement of the displacement on an artificial boundary enclosing the obstacle. In this paper, we consider both the direct and inverse problems. The direct problem is shown to have a unique weak solution by examining its variational formulation. The domain derivative is derived for the displacement with respect to the variation of the surface. A continuation method with respect to the frequency is developed for the inverse problem. Numerical experiments are presented to demonstrate the effectiveness of the proposed method.
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).
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 ...
Coherency in Neutrino-Nucleus Elastic Scattering
Kerman, S; Deniz, M; Wong, H T; Chen, J -W; Li, H B; Lin, S T; Liu, C -P; Yue, Q
2016-01-01
Neutrino-nucleus elastic scattering provides a unique laboratory to study the quantum mechanical coherency effects in electroweak interactions, towards which several experimental programs are being actively pursued. We report results of our quantitative studies on the transitions towards decoherency. A parameter ($\\alpha$) is identified to describe the degree of coherency, and its variations with incoming neutrino energy, detector threshold and target nucleus are studied. The ranges of $\\alpha$ which can be probed with realistic neutrino experiments are derived, indicating complementarity between projects with different sources and targets. Uncertainties in nuclear physics and in $\\alpha$ would constrain sensitivities in probing physics beyond the standard model. The maximum neutrino energies corresponding to $\\alpha$>0.95 are derived.
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.
Proton-proton elastic scattering at ultrahigh energies
Saleem, M.; Shaukat, M.A.; Fazal-e-Aleem (University of the Punjab, Lahore (Pakistan). Dept. of Physics)
1981-05-30
The authors use a geometrical model of high-energy pp elastic scattering as proposed by Chou and Yong to analyse experimental data available at present and consider the predictions of the dipole pomeron model for pp elastic scattering at ultrahigh energies. Theoretical results for differential cross sections are compared with experimental data.
Anisotropy function for pion-proton elastic scattering
Saleem, Mohammad; Fazal-e-Aleem; Rashid, Haris
1988-09-01
By using the generalised Chou-Yang model and the experimental data on ..pi../sup -/p elastic scattering at 200 GeV/c, the anisotropy function which reflects the non-isotropic nature of elastic scattering is computed for the reaction ..pi../sup -/p -> ..pi../sup -/p.
Anisotropy function for proton-proton elastic scattering
Saleem, Mohammad; Fazal-e-Aleem; Azhar, I.A. (Punjab Univ., Lahore (Pakistan). Centre for High Energy Physics)
1990-07-01
By using the generalized Chou-Yang model and the experimental data on pp elastic scattering at 53 GeV, the anisotropy function which reflects the non-isotropic nature of elastic scattering is computed for the reaction pp{yields}pp. (author).
Forward Physics at the LHC; Elastic Scattering
Fiore, R; Orava, R; Predazzi, E; Prokudin, A; Selyugin, O
2008-01-01
The following effects in the nearly forward ("soft") region of the future LHC are proposed to be investigated: 1) At small $|t|$ the fine structure of the cone (Pomeron) shouldbe scrutinized: a) a break of the cone near $t\\approx - 0.1$ ~ GeV$^2,$ due to the two-pion threshold, and required by t-channel unitarity, is expected, and b) possible small-period oscillations between $t=0$ and the dip region. 2) In measuring the elastic $pp$ scattering and total $pp$ cross section at the LHC, the experimentalists are urged to treat the total cross section $\\sigma_t,$ the ratio $\\rho$, the forward slope $B$ and the luminosity ${\\cal L}$ as free arameters, and to publish model-independent results on ${dN/{dt}}.$ 3) Of extreme interest are the details of the expected diffraction minimum in the differential cross section. Its position, expected in the interval $0.4<-t<1$ GeV$^2$ at the level of about $10^{-2} {\\rm mb} \\cdot$ GeV$^{-2}\\div 10^{-1} {\\rm mb}\\cdot$ GeV$^{-2}$, cannot be predicted unambiguously, and its...
Momentum-space optical potential SND elastic scattering calculations
Wolfe, D.H.; Hynes, M.V.; Picklesimer, A.; Tandy, P.C.; Thaler, R.M.
1983-01-01
Initial results are presented for proton-nucleus elastic scattering observables calculated with a newly developed microscopic momentum-space code. This is the first phase of a program to treat elastic and inelastic scattering consistently via an integral equation approach. A number of microscopic features which are often approximated or ignored are quite amenable to exact treatment within this approach, e.g. non-local effects in elastic scattering, and inelastic effects which are non-linear in the NN t-matrix and target densities but nevertheless confined to one participating nucleon. 3 references.
Nucleas (hadron) nucleus elastic scattering and geometrical picture
Aleem F.; Ali, S.; Saleem, M. [Univ. of the Punjab, Lahore (Pakistan)
1995-08-01
A comprehensive explanation of nucleus-nucleus and hadron-nucleus elastic scattering is elusive ever since the measurements of these reactions were made. By proposing energy dependent hadronic form factors for deuteron and alpha, in analogy to that of the proton as suggested by Chou and Yang recently, the authors have fitted all the available data for alpha-alpha and deuteron-deuteron elastic scattering. In order to further verify the validity of the proposed form factor, they have also fitted the data for proton-alpha and proton-deuteron elastic scattering. It is concluded that the hadronic matter is expanding with an increase in energy. 30 refs., 11 figs.
SPIN DEPENDENCE IN ELASTIC SCATTERING IN THE CNI REGION.
BRAVAR, A.; MAKDISI, Y.; ET AL.
2004-10-10
The interference of the electromagnetic spin-flip amplitude with a hadronic spin-nonflip amplitude in the elastic scattering of hadrons leads to significant spin dependencies at very low 4-momentum transfer t (0.001 < |t| < 0.01 (GeV/c){sup 2}). This kinematical region is known as the Coulomb Nuclear Interference (CNI) region. First results on spin effects in polarized proton-proton elastic scattering in the CNI region at 100 GeV from the 2004 polarized proton run at RHIC are presented. Preliminary results on A{sub N} in the elastic scattering of polarized protons off a carbon target over a wide energy range from 4 GeV to 100 GeV from AGS and RHIC are presented as well. These results allow us to further investigate the spin dependence in elastic scattering and the mechanisms at work.
Uniqueness in inverse elastic scattering with finitely many incident waves
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.)
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)
Effects of shear elasticity on sea bed scattering: numerical examples.
Ivakin, A N; Jackson, D R
1998-01-01
It is known that marine sediments can support both compressional and shear waves. However, published work on scattering from irregular elastic media has not examined the influence of shear on sea bed scattering in detail. A perturbation model previously developed by the authors for joint roughness-volume scattering is used to study the effects of elasticity for three sea bed types: sedimentary rock, sand with high shear speed, and sand with "normal" shear wave speed. Both bistatic and monostatic cases are considered. For sedimentary rock it is found that shear elasticity tends to increase the importance of volume scattering and decrease the importance of roughness scattering relative to the fluid case. Shear effects are shown to be small for sands.
Momentum-space optical potential SND elastic scattering calculations
Wolfe, D. H.; Hynes, M. V.; Picklesimer, A.; Tandy, P. C.; Thaler, R. M.
1983-03-01
Initial results are presented for proton-nucleus elastic scattering observables calculated with a newly developed microscopic momentum-space code. This is the first phase of a program to treat elastic and inelastic scatterig consistently via an integral equation approach. A number of microscopic features which are often approximated or ignored are quite amenable to exact treatment within this approach, e.g. non-local effectss in elastic scattering, and inelastic effects which are non-linear in the NN t-matrix and target densities but nevertheless confined to one participating nucleon.
Quasi-elastic neutron scattering studies of protein dynamics
Rorschach, H.E.
1993-05-25
Results that shed new light on the study of protein dynamics were obtained by quasi-elastic neutron scattering. The triple axis instrument H-9 supplied by the cold source was used to perform a detailed study of the quasi-elastic spectrum and the Debye-Waller factor for trypsin in powder form, in solution, and in crystals. A preliminary study of myoglobin crystals was also done. A new way to view the results of quasi-elastic scattering experiments is sketched, and the data on trypsin are presented and analyze according to this new picture.
Quasi-elastic nuclear scattering at high energies
Cucinotta, Francis A.; Townsend, Lawrence W.; Wilson, John W.
1992-01-01
The quasi-elastic scattering of two nuclei is considered in the high-energy optical model. Energy loss and momentum transfer spectra for projectile ions are evaluated in terms of an inelastic multiple-scattering series corresponding to multiple knockout of target nucleons. The leading-order correction to the coherent projectile approximation is evaluated. Calculations are compared with experiments.
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.
Deuteron-deuteron elastic scattering at high energies
Fazal-e-Aleem; Ali, S. (Univ. of the Punjab, Lahore (Pakistan))
1991-04-01
The eikonal picture which has theoretical foundations in some areas of physics has been successful in explaining various aspects of elastic scattering at high energies. Chou and Yang first proposed a preliminary version of the eikonal model for hadron-hadron elastic scattering. The model is based on geometrical considerations in which hadrons are treated as extended objects. Elastic scattering then results from the propagation of attenuated wave function. By assuming that at high energies the scattering amplitude is purely imaginary and that the hadronic matter distribution is proportional to the charge distribution on protons, Durand and Lipes studied high energy pp scattering on the basis of this prestine model. Later on, the model was extended to other elastic reactions. However, a survey of literature shows that it has been successful only in the diffraction peak region. It has been shown that the pristine Chou-Yange model can explain the differential cross section for deuteron-deuteron elastic scattering at {radical}s = 53 GeV in the diffraction peak region. In order to fit the large momentum transfer data, the generalized Chou-Yang model is used.
Delta excitation in deuteron-proton elastic scattering
Ladygina, N.B. [Joint Institute for Nuclear Research, LHEP, Dubna (Russian Federation)
2016-07-15
Deuteron-proton elastic scattering is studied in the multiple scattering expansion formalism. The four contributions are taken into account: one-nucleon exchange, single and double scattering, and Δ-isobar excitation. The presented approach was applied to describe the differential cross sections at deuteron energies between 500 and 1300 MeV in a whole angular range. The obtained results are compared with the experimental data. (orig.)
Scattering from elastic sea beds: first-order theory.
Jackson, D R; Ivakin, A N
1998-01-01
A perturbation model for high-frequency sound scattering from an irregular elastic sea bed is considered. The sea bed is assumed homogeneous on the average and two kinds of irregularities are assumed to cause scattering: roughness of the water-sea bed interface and volume inhomogeneities of the sediment mass density and the speeds of compressional and shear waves. The first-order small perturbation approximation is used to obtain expressions for the scattering amplitude and bistatic scattering strength. The angular dependence of the scattering strength is calculated for sedimentary rock and the influence of shear elasticity is examined by comparison with the case of a fluid bottom. Shear effects are shown to be strong and complicated.
Proton Elastic Scattering from 14Be and Halo Effects
GU Bai-Ping; REN Zhong-Zhou
2006-01-01
The elastic scattering ofp-14Be system at Elab = 200 MeV is evaluated within the relativistic impulse approximation. We discuss the effects of the halo neutrons on the three observables of the elastic scattering system,such as differential cross section dσ/dΩ, analyzing power Ay and spin rotation Q. The results of the three observables of the elastic scattering of p-14Be system are compared with those of p-12C and p-16O systems at the same energy as Elab = 200 MeV. We have found that in the small angular region the Ay and Q, as well as dσ/dΩ, are quite sensitive to the nucleon density distributions on the surface of the target nucleus and offer some unique behaviors of halo nuclei.
Resonance scattering of canonical elastic shells in absorbing fluid medium
ZHUO Linkai; FAN Jun; TANG Weilin
2008-01-01
Resonance scattering of elastic spherical shell and cylindrical shell while the sur-rounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable resul twould be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surround-ing fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little in fluence on the low-frequency resonance scattering induced by the filler inside the shell.
Elastic cross sections for electron-carbon scattering
Liu Jun-Bo; Wang Yang; Zhou Ya-Jun
2007-01-01
We used the close-coupling optical (CCO) approach to investigate the open-shell carbon atom. The elastic cross sections have been presented at the energies below 90eV, and the present CCO results have been compared with other theoretical results. We found that polarization and the continuum states have significant contributions to the elastic cross sections. The present calculations show that the CCO method is capable of calculating electron scattering from open-shell atoms.
Elastic scattering, polarization and absorption of relativistic antiprotons on nuclei
Larionov, A B
2016-01-01
We perform Glauber model calculations of the antiproton-nucleus elastic and quasielastic scattering and absorption in the beam momentum range $\\sim 0.5\\div10$ GeV/c. A good agreement of our calculations with available LEAR data and with earlier Glauber model studies of the $\\bar p A$ elastic scattering allows us to make predictions at the beam momenta of $\\sim 10$ 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 $\\bar p A$ case due to smaller absolute value of the ratio of the real-to-imaginary part of the elementary elastic amplitude. Significant polarization signal for $\\bar p A$ elastic scattering at 10 GeV/c is expected. We have also revealed a strong dependence of the $\\bar p A$ absorption cross section on the slope parameter of the transverse momentum dependence of the elementary $\\bar pN$ amplitude. The $\\bar p A$ optical potential is 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.
Low-|t| structures in elastic scattering at the LHC
Jenkovszky, Laszlo
2014-01-01
Possible low-$|t|$ structures in the differential cross section of $pp$ elastic scattering at the LHC are predicted. It is argued that the change of the slope of the elastic cross section near $t=-0.1$ GeV$^2$ has the same origin as that observed in 1972 at the ISR, both related to the $4m_{\\pi}^2$ branch point in the $|t|$-channel of the scattering amplitude. Apart from that structure, tiny oscillations at small $|t|$ may be present on the cone at low $|t|$.
E710, Proton, Antiproton Elastic Scattering at Tevatron Energies
Sadr, Sasan
Experiment E710, located at site E0 of the Tevatron collider at Fermilab, was conceived in order to measure pp 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 rho, 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.
Angular Dispersion and Deflection Function for Heavy Ion Elastic Scattering
BAI Zhen; MAO Rui-Shi; YUAN Xiao-Hua; Xu Zhi-Guo; ZHANG Hong-Bin; XU Hua-Gen; QI Hui-Rong; WANG Yue; JIA Fei; WU Li-Jie; DING Xian-Li; WANG Qi; GAO Qi; GAO Hui; LI Song-Lin; LI Jun-Qing; ZHANG Ya-Peng; XIAO Guo-Qing; JIN Gen-Ming; REN Zhong-Zhou; ZHOU Shan-Gui; XU Wang; HAN Jian-Long; Fan Gong-Tao; ZHANG Shuang-Quan; PANG Dan-Yang; SERGEY Yu-Kun; XIAO Zhi-Gang; XU Hu-Shan; SUN Zhi-Yu; HU Zheng-Guo; ZHANG Xue-Ying; WANG Hong-Wei
2007-01-01
The differential cross sections for elastic scattering products of17 F on 208 Pb have been measured.The angular dispersion plots of In(dσ/dθ)versus θ2 are obtained from the angular distribution of the elastic scattering differential cross sections.Systematical analysis on the angular dispersion for the available experimental data indicates that there is an angular dispersion turning angle at forward angular range within the grazing angle.This turning angle can be clarified as nuclear rainbow in classical deflection function.The exotic behaviour of the nuclear rainbow angle offers a new probe to investigate the halo and skin phenomena.
LHC optics and elastic scattering measured by the TOTEM experiment
Nemes, Frigyes
2016-01-01
The TOTEM experiment at the LHC has measured proton-proton elastic scattering in dedicated runs at $\\sqrt{s}=7$ and 8 TeV centre-of-mass LHC energies. The proton-proton total cross-section $\\sigma_{\\rm tot}$ has been derived for both energies using a luminosity independent method. TOTEM has excluded a purely exponential differential cross-section for elastic proton-proton scattering with significance greater than 7$\\sigma$ in the $|t|$ range from 0.027 to 0.2 GeV$^{2}$ at $\\sqrt{s}=8$ TeV.
Isospin effects in elastic proton-nucleus scattering
Chinn, C. R.; Elster, Ch.; Thaler, R. M.
1993-05-01
Isovector effects in proton-nucleus elastic scattering at medium energies are studied. The accuracy of the Kerman-McManus-Thaler isospin averaging procedure is found to be very good for nuclei larger than 4He. Studies of 40Ca and 208Pb suggest that the surface neutrons may be pulled in somewhat relative to the protons, although uncertainties in the detailed applicability of the present truncation of the multiple scattering treatment render firm conclusions premature.
Isospin effects in elastic proton-nucleus scattering
Chinn, C.R. (Service de Physique et Techniques Nucleaires, Centre d' Etudes de Bruyeres-le-Chatel, B.P. No. 12, 91680 Bruyeres-le-Chatel (France)); Elster, C. (Institute of Nuclear and Particle Physics and Department of Physics, Ohio University, Athens, Ohio 45701 (United States)); Thaler, R.M. (Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States) Case Western Reserve University, Cleveland, Ohio 44106 (United States))
1993-05-01
Isovector effects in proton-nucleus elastic scattering at medium energies are studied. The accuracy of the Kerman-McManus-Thaler isospin averaging procedure is found to be very good for nuclei larger than [sup 4]He. Studies of [sup 40]Ca and [sup 208]Pb suggest that the surface neutrons may be pulled in somewhat relative to the protons, although uncertainties in the detailed applicability of the present truncation of the multiple scattering treatment render firm conclusions premature.
Energy distribution of elastically scattered electrons from double layer samples
Tőkési, K.; Varga, D.
2016-02-01
We present a theoretical description of the spectra of electrons elastically scattered from thin double layered Au-C samples. The analysis is based on the Monte Carlo simulation of the recoil and Doppler effects in reflection and transmission geometries of the scattering at a fixed angle of 44.3 ° and a primary energy of 40 keV. The relativistic correction is taken into account. Besides the experimentally measurable energy distributions the simulations give many partial distributions separately, depending on the number of elastic scatterings (single, and multiple scatterings of different types). Furthermore, we present detailed analytical calculations for the main parameters of the single scattering, taking into account both the ideal scattering geometry, i.e. infinitesimally small angular range, and the effect of the real, finite angular range used in the measurements. We show our results for intensity ratios, peak shifts and broadenings for four cases of measurement geometries and layer thicknesses. While in the peak intensity ratios of gold and carbon for transmission geometries were found to be in good agreement with the results of the single scattering model, especially large deviations were obtained in reflection geometries. The separation of the peaks, depending on the geometry and the thickness, generally smaller, and the peak width generally larger than it can be expected from the nominal values of the primary energy, scattering angle, and mean kinetic energy of the atoms. We also show that the peaks are asymmetric even for the case of the single scattering due to the finite solid angle. Finally, we present a qualitative comparison with the experimental data. We find our resulting energy distribution of elastically scattered electrons to be in good agreement with recent measurements.
Laser-Assisted Elastic Electron Scattering from Argon
HU Qiu-Bo; SUN Jin-Feng
2009-01-01
The second Born approximation (SBA) theory is applied to the study of electron-atom scattering in the presence of a CO2 laser field. The absolute differential cross sections of e-At scattering are calculated with multiphoton exchange in two special scattering geometries G1 (for small-angle scattering) and G2. For geometry G1, compared with the results of two different model potentials for electron elastic scattering by atoms, it is found that electronatom polarization potential plays an important role in laser-assisted electron-atom scattering. Some calculational results in geometries G2 are given. Our results are found to be better than other theoretical results as compared with the experimental data in geometries G1 and G2.
Contraband detection via neutron elastic scattering
Gomberg, H.J.; Charatis, G.; Brundage, J. [Penetron, Inc., Ann Arbor, MI (United States)] [and others
1993-04-01
Reliable detection of explosives and narcotics depends on generating signatures of compounds which characterize them. Major explosives and also alkaloid narcotics contain unique concentrations of Carbon (C), Nitrogen (N), and Oxygen (O). The kinematic energy shifts of neutrons scattered through angles larger than 140{degrees} allows separate determinations of C, N, and O; ratios of N/C and O/C together give clear signatures of the presence of plastic explosives or narcotics. The ability to detect these signatures under conditions similar to those that would obtain for airport screening has been demonstrated for neutrons for energies less {le} 3 MeV. Strong N resonances and a deep window for scattering from O enhance the confidence of element quantification. Detection of contraband in large cargo containers presents a much more difficult problem. Use of higher energy neutrons is now being tested for shielding penetration, so narcotic signatures could be identified behind the shielding of cargo containers. Scattered neutron spectra, or {open_quotes}signatures{close_quotes} of different organic compounds will be presented.
Quasi-Elastic Scattering in MINERvA
McFarland, Kevin S
2011-01-01
Determination of the quasi-elastic scattering cross-section over a broad range of neutrino energies, nuclear targets and Q^2 is a primary goal of the MINERvA experiment. We present preliminary comparisons of data and simulation in a sample rich in anti-{\
Dual absorptive model and np elastic scattering at high energies
Saleem, M.; Fazal-e-Aleem
1980-06-01
The most recent measurements of the angular distribution and total cross-sections in np elastic scattering at high energies from 70 to 400 GeV/c have been fitted by using the dual absorptive model. Comparison has also been made with the Kane-Siedl model and the simple Regge pole model.
Neutron-proton elastic scattering at high energies
Saleem, M.; Fazal-e-Aleem (Punjab Univ., Lahore (Pakistan). Dept. of Physics)
1980-09-06
The most recent measurements of the differential and total cross sections of neutron-proton elastic scattering from 70 to 400 GeV/c have been explained by using rho as a simple pole and pomeron as a dipole. The predictions are also made regarding the energy dependence of dip and bump structure in angular distribution.
Elastic scattering of surface plasmon polaritons: Modeling and experiment
Bozhevolnyi, Sergey I.; Coello, V.
1998-01-01
excitation wavelengths (594 and 633 nm) and different metal (silver and gold) films. The near-field optical images obtained are related to the calculated SPP intensity distributions demonstrating that the model developed can be successfully used in studies of SPP elastic scattering, e.g., to design...
Rayleigh scattering and nonlinear inversion of elastic waves
Gritto, R.
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 {minus}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{sub 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.
Numerical modelling of multiple scattering between two elastical particles
Bjørnø, Irina; Jensen, Leif Bjørnø
1998-01-01
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...... 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...
Acoustic scattering reduction using layers of elastic materials
Dutrion, Cécile; Simon, Frank
2017-02-01
Making an object invisible to acoustic waves could prove useful for military applications or measurements in confined space. Different passive methods have been proposed in recent years to avoid acoustic scattering from rigid obstacles. These techniques are exclusively based on acoustic phenomena, and use for instance multiple resonators or scatterers. This paper examines the possibility of designing an acoustic cloak using a bi-layer elastic cylindrical shell to eliminate the acoustic field scattered from a rigid cylinder hit by plane waves. This field depends on the dimensional and mechanical characteristics of the elastic layers. It is computed by a semi-analytical code modelling the vibrations of the coating under plane wave excitation. Optimization by genetic algorithm is performed to determine the characteristics of a bi-layer material minimizing the scattering. Considering an external fluid consisting of air, realistic configurations of elastic coatings emerge, composed of a thick internal orthotopic layer and a thin external isotropic layer. These coatings are shown to enable scattering reduction at a precise frequency or over a larger frequency band.
Sound scattering from partially water-filled elastic spherical shell with an internal elastic plate
SUN Yang; XU Haiting
2008-01-01
According to the equation of motion in the elastic medium and integral equation of target scattering, the sound scattering from the partially water-filled elastic spherical shells with and without an inner plate is studied using the finite element and boundary element method,and the scattering normalized form functions of the shell filled with different volume of water are computed and the mechanism of resonance scattering is analyzed. The results show that the resonance of the shell with partially water-filled and without the plate is mainly related to the volume of water, and the resonance is produced by inner water and the spherical shell. The resonance characteristics of partially water-filled elastic shell with the plate are similar to that of empty structured elastic spherical shell, and the sound field in inner water is weaker which indicates the main resonance characteristics are decided by spherical shell and the plate. In addition, the scattering characteristics of spherical shell with plate and one side full water-filled are greatly different from the partially water-filled ones.
Spin entanglement in elastic electron scattering from lithium atoms
Bartschat, K
2016-01-01
In two recent papers (Phys. Rev. Lett. {\\bf 116} (2016) 033201; Phys. Rev. A {\\bf 94} (2016) 032331), the possibility of continuously varying the degree of entanglement between an elastically scattered electron and the valence electron of an alkali target was discussed. In order to estimate how well such a scheme may work in practice, we present results for elastic electron scattering from lithium in the energy regime of 1$-$5~eV and the full range of scattering angles $0^\\circ - 180^\\circ$. The most promising regime for Bell-correlations in this particular collision system are energies between about 1.5 eV and 3.0 eV, in an angular range around $110^\\circ \\pm 10^\\circ$. In addition to the relative exchange asymmetry parameter, we present the differential cross section that is important when estimating the count rate and hence the feasibility of experiments using this system.
Elastic scattering of gamma rays and X-rays
Kane, P.P. [Physics Department, Indian Institute of Technology, Powai, Mumbai 400076 (India)]. E-mail: ppkane@vsnl.com
2005-12-15
Studies of elastic gamma ray scattering were pursued independently by the groups of Prof. Ghose and the author for several decades in spite of somewhat meagre support. Several techniques for such studies developed by the two groups and some of the results obtained in the energy range from tens of keV to about 1.5 MeV are described briefly. The theoretical background necessary for understanding these results is also outlined. The results showed the importance of Modified Relativistic Form Factor (MRFF) approximation in the explanation of atomic Rayleigh scattering cross sections in the small angle regime and the necessity for an inclusion of real Delbrueck scattering amplitudes at large scattering angles. Dispersion corrections to form factor amplitudes or the so-called anomalous scattering factors are shown to be needed at photon energies close to electron binding energy thresholds. A few promising future extensions of such studies are indicated at the end.
Near-edge elastic photon scattering in amorphous systems
Hugtenburg, R.P. [School of Physics and Astronomy, University of Birmingham, B15 2TT (United Kingdom); Queen Elizabeth Medical Centre, University Hospital Birmingham, B15 2TH (United Kingdom)], E-mail: r.p.hugtenburg@bham.ac.uk; England, D.W. [Queen Elizabeth Medical Centre, University Hospital Birmingham, B15 2TH (United Kingdom); Bradley, D.A. [Department of Physics, School of Electronics and Physical Sciences, University of Surrey, GU2 7XH (United Kingdom)
2007-10-15
The structure of valence and unoccupied electron orbitals and the neighbouring electron density distribution of atoms and ions in amorphous systems can be examined through use of resonance in the elastic photon scattering-cross-section in the vicinity of core atomic orbital energies. So-called anomalous X-ray scattering (AXS) is a mode of analysis that offers similar information to that of EXAFS but can be obtained concurrently with diffraction mode imaging. Of interest is whether the dilute-ion aqueous system provides an environment suitable for testing independent particle approximation (IPA) predictions. With the aqueous environment as the reference system for calibrating relative cross-sections, particular challenges include photons scattered by the medium being subsequently absorbed by the ion, limiting the thickness of the attenuating medium and motivating use of bright synchrotron photon sources where tunable X-rays are obtained at sub-eV resolution using a Si 111 monochromator. Measured scattering intensities and fluorescent yields were compared and shown to agree qualitatively with Monte Carlo calculations utilising amplitudes calculated from modified form-factors with anomalous scatter factors at a resolution of several eV determined from the Dirac-Slater exchange potential. Experimentally determined form-factors for pure water were used to calibrate fluorescent yield and elastic scattering intensities for measurement of the energy dependent variation of these quantities near edge and XRF imaging of the Zn concentration in wax mounted, formalin fixed, breast tumour samples. Results indicate the distribution of Zn at higher resolution than sampling dimensions used in previous studies. Shifts in the position and profile of K-edge absorption and elastic scattering features in aqeuous Zn, Zn doped sol-gel glass and Zn in tissue are shown to reflect changes in the atomic charge state and environment and offer support for the presence of non-nutrient Zn bearing
Near-edge elastic photon scattering in amorphous systems
Hugtenburg, R. P.; England, D. W.; Bradley, D. A.
2007-10-01
The structure of valence and unoccupied electron orbitals and the neighbouring electron density distribution of atoms and ions in amorphous systems can be examined through use of resonance in the elastic photon scattering-cross-section in the vicinity of core atomic orbital energies. So-called anomalous X-ray scattering (AXS) is a mode of analysis that offers similar information to that of EXAFS but can be obtained concurrently with diffraction mode imaging. Of interest is whether the dilute-ion aqueous system provides an environment suitable for testing independent particle approximation (IPA) predictions. With the aqueous environment as the reference system for calibrating relative cross-sections, particular challenges include photons scattered by the medium being subsequently absorbed by the ion, limiting the thickness of the attenuating medium and motivating use of bright synchrotron photon sources where tunable X-rays are obtained at sub-eV resolution using a Si 111 monochromator. Measured scattering intensities and fluorescent yields were compared and shown to agree qualitatively with Monte Carlo calculations utilising amplitudes calculated from modified form-factors with anomalous scatter factors at a resolution of several eV determined from the Dirac-Slater exchange potential. Experimentally determined form-factors for pure water were used to calibrate fluorescent yield and elastic scattering intensities for measurement of the energy dependent variation of these quantities near edge and XRF imaging of the Zn concentration in wax mounted, formalin fixed, breast tumour samples. Results indicate the distribution of Zn at higher resolution than sampling dimensions used in previous studies. Shifts in the position and profile of K-edge absorption and elastic scattering features in aqeuous Zn, Zn doped sol-gel glass and Zn in tissue are shown to reflect changes in the atomic charge state and environment and offer support for the presence of non-nutrient Zn bearing
$pp$ Elastic Scattering at LHC and Nucleon Structure
Islam, M M; Prokudin, A V
2003-01-01
High energy elastic pp differential cross section at LHC at the c.m. energy 14 TeV is predicted using the asymptotic behavior of sigma-tot(s) and rho(s), and the measured pbar-p differential cross section at sqrt{s}=546 GeV. The phenomenological investigation has progressively led to an effective field theory model that describes the nucleon as a chiral bag embedded in a quark-antiquark condensed ground state. The measurement of pp elastic scattering at LHC up to large |t| >~ 10 GeV^2 by the TOTEM group will be crucial to test this structure of the nucleon.
Scattering of time-harmonic elastic waves by an elastic inclusion with quadratic nonlinearity.
Tang, Guangxin; Jacobs, Laurence J; Qu, Jianmin
2012-04-01
This paper considers the scattering of a plane, time-harmonic wave by an inclusion with heterogeneous nonlinear elastic properties embedded in an otherwise homogeneous linear elastic solid. When the inclusion and the surrounding matrix are both isotropic, the scattered second harmonic fields are obtained in terms of the Green's function of the surrounding medium. It is found that the second harmonic fields depend on two independent acoustic nonlinearity parameters related to the third order elastic constants. Solutions are also obtained when these two acoustic nonlinearity parameters are given as spatially random functions. An inverse procedure is developed to obtain the statistics of these two random functions from the measured forward and backscattered second harmonic fields.
Scattered antiproton polarization in pp elastic scattering at 220 MeV in bubble chamber
Ohsugi, T
1973-01-01
The polarization of antiproton scattering in pp elastic collision has been measured in the four intervals of the CM scattering angle theta /sup */ less than 90 degrees by means of double scattering in a bubble chamber. The analysis has been performed on the basis of 999 double elastic events which have been found in about 100K pictures of the 81- cm Saclay hydrogen bubble chamber exposed to a 0.7 GeV/c antiproton beam from the CERN PS. The obtained values of polarization show the maximum value 0.52+or-0.19 at theta /sup */=56 degrees . The polarization for pp scattering seems to be larger than that for pp scattering. The results are also compared with the potential model by Bryan and Phillips (1968) and with the modified diffraction model by Frahn and Venter (1964). Possible systematic errors in the present experiment are discussed in detail. (17 refs).
Relativistic effects in elastic scattering of electrons in TEM.
Rother, Axel; Scheerschmidt, Kurt
2009-01-01
Transmission electron microscopy typically works with highly accelerated thus relativistic electrons. Consequently the scattering process is described within a relativistic formalism. In the following, we will examine three different relativistic formalisms for elastic electron scattering: Dirac, Klein-Gordon and approximated Klein-Gordon, the standard approach. This corresponds to a different consideration of spin effects and a different coupling to electromagnetic potentials. A detailed comparison is conducted by means of explicit numerical calculations. For this purpose two different formalisms have been applied to the approaches above: a numerical integration with predefined boundary conditions and the multislice algorithm, a standard procedure for such simulations. The results show a negligibly small difference between the different relativistic equations in the vicinity of electromagnetic potentials, prevailing in the electron microscope. The differences between the two numeric approaches are found to be small for small-angle scattering but eventually grow large for large-angle scattering, recorded for instance in high-angle annular dark field.
Characteristic Dirac Signature in Elastic Proton Scattering at Intermediate Energies
Hynes, M. V.; Picklesimer, A.; Tandy, P. C.; Thaler, R. M.
1984-03-01
Nonrelativistic nucleon-nucleus first-order multiple-scattering calculations are extended to include virtual (Dirac) negative energy states of just the projectile. This effect may be thought of as virtual NN¯ pair production and annihilation in the field of the nucleus. This extension leads to a parameter-free Dirac description of the projectile in elastic proton scattering which produces a characteristic effect in spin observables over a wide range of energies which is in agreement with experiment. This Dirac signature is extremely stable with respect to uncertainties in the microscopic input.
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.
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.
Phenomenological models of elastic nucleon scattering and predictions for LHC
Kundrat, V; Lokajicek, M; Prochazka, J
2011-01-01
The hitherto analyses of elastic collisions of charged nucleons involving common influence of Coulomb and hadronic scattering have been based practically on West and Yennie formula. However, this approach has been shown recently to be inadequate from experimental as well as theoretical points of view. The eikonal model enabling to determine physical characteristics in impact parameter space seems to be more pertinent. The contemporary phenomenological models admit, of course, different distributions of collision processes in the impact parameter space and cannot give any definite answer. Nevertheless, some predictions for the planned LHC energy that have been given on their basis may be useful, as well as the possibility of determining the luminosity from elastic scattering. (C) 2010 Elsevier B.V. All rights reserved.
Mapping from quasi-elastic scattering to fusion reactions
Hagino, K
2014-01-01
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 $^{16}$O+$^{144}$Sm, $^{58}$Ni+$^{58}$Ni, and $^{12}$C+$^{12}$C systems.
Theoretical Aspects of Coherent Elastic Neutrino Nucleus Scattering
McLaughlin, Gail
2014-09-01
We will discuss the physics potential of coherent elastic neutrino nucleus scattering. This standard model process has never been directly measured, although there are a number of experiments proposed at stopped pion/muon or reactor sites that could make such a first detection. Such a measurement opens up the possibility for a number of interesting physics probes. We will review these from a theoretical point of view, with a particular focus on the nuclear-neutron form factor.
Hard diffraction from quasi-elastic dipole scattering
Bialas, A
1996-01-01
The contribution to diffraction dissociation of virtual photons due to quasi-elastic scattering of the q-\\bar q component is calculated in the framework of the QCD dipole picture. Both longitudinal and transverse components of the cross-section are given. It is shown that, at fixed mass of the diffractively produced system, quantum mechanical interference plays an important r\\^ ole. Phenomenological consequences are discussed.
$^{-} - {}^{12}C$ elastic scattering above the resonance using diffraction model
M R Arafah
2008-01-01
Phenomenological analysis of the $^{-}- ^{12}C$ elastic scattering differential cross-section at 400, 486, 500, 584, 663, 672 and 766 MeV is presented. The analysis is made in the diffraction model framework using the recently proposed parametrization of the phase-shift function. Good description of the experimental data is achieved at all energies. Microscopic interpretation of the parameters of the phase-shift function is provided in terms of Helm's model density parameters.
Proton-proton elastic scattering at ultrahigh energies
Saleem, M.; Shaukat, M.A.; Fazal-e-Aleem (University of the Punjab, Lahore (Pakistan). Dept. of Physics)
1981-05-30
Recent experimental results on proton-proton elastic scattering at high energies are discussed in the context of the comments by Chou and Yang. There does not appear to be any tendency that the experimental results would agree with the predictions of the geometrical model even at ultrahigh energies. The angular distribution structure as described by using the dipole pomeron is consistent with the experimental data at presently available high energies and predicts results quite different from the geometrical model.
Elastic diffractive scattering of nucleons at ultra-high energies
Godizov, A.A., E-mail: anton.godizov@gmail.com
2014-07-30
A simple Regge-eikonal model with the eikonal represented as a single-reggeon-exchange term is applied to description of the nucleon–nucleon elastic diffractive scattering at ultra-high energies. The range of validity of the proposed approximation is discussed. The model predictions for the proton–proton cross-sections at the collision energy 14 TeV are given.
Recent Measurements of Neutrino-Nucleus Quasi-Elastic Scattering
Wascko, M O
2011-01-01
We present recent measurements of neutrino charged current quasi-elastic (CC QE) scattering, nu_mu + p -> mu- + n. Measurements of CC QE on carbon near 1 GeV by MiniBooNE and SciBooNE, as well as measurements on iron at 3 GeV by MINOS, disagree with current interaction models, while measurements at higher energies on carbon by NOMAD show excellent agreement with those same models.
ELASTIC WAVE SCATTERING AND DYNAMIC STRESS IN COMPOSITE WITH FIBER
胡超; 李凤明; 黄文虎
2003-01-01
Based on the theory of elastic dynamics, multiple scattering of elastic waves and dynamic stress concentrations in fiber-reinforced composite were studied. The analyticalexpressions of elastic waves in different region were presented and an analytic method tosolve this problem was established. The mode coefficients of elastic waves were determinedin accordance with the continuous conditiors of displacement and stress on the boundary ofthe multi-interfaces. By making use of the addition theorem of Hankel functions, theformulations of scattered wave fields in different local coordinates were transformed intothose in one local coordinate to determine the unknown coefficients and dynamic stressconcentration factors. The influence of distance between two inclusions, material propertiesand structural size on the dynamic stress concentration factors near the interfaces wasanalyzed. It indicates in the analysis that distance between two inclusions, materialproperties and structural size has great influence on the dynamic properties of fiber-reinforced composite near the interfaces. As examples, the numerical results of dynamicstress concentration factors near the interfaces in a fiber- reinforced composite are presentedand discussed.
Deconstruction and Elastic pi pi Scattering in Higgsless Models
Chivukula, R S; Kurachi, M; Simmons, E H; Tanabashi, M; He, Hong-Jian; Kurachi, Masafumi; Simmons, Elizabeth H.; Tanabashi, Masaharu
2007-01-01
We study elastic pion-pion scattering in global linear moose models and apply the results to a variety of Higgsless models in flat and AdS space using the Equivalence Theorem. In order to connect the global moose to Higgsless models, we first introduce a block-spin transformation which corresponds, in the continuum, to the freedom to perform coordinate transformations in the Higgsless model. We show that it is possible to make an "f-flat" deconstruction in which all of the f-constants f_j of the linear moose model are identical; the phenomenologically relevant f-flat models are those in which the coupling constants of the groups at either end of the moose are small - corresponding to the global linear moose. In studying pion-pion scattering, we derive various sum rules, including one analogous to the KSRF relation, and use them in evaluating the low-energy and high-energy forms of the leading elastic partial wave scattering amplitudes. We obtain elastic unitarity bounds as a function of the mass of the lighte...
Angularly-resolved elastic light scattering of micro-particles
Aptowicz, Kevin B.
From microbiology to astrophysics, the scientific community has long embraced elastic light scattering from small particles as a diagnostic tool. Elastic light scattering has an extremely large scattering cross-section, allowing for single particle interrogation. This is critical in applications where trace amounts of suspect particles are to be detected in a diverse background of natural aerosols. By angularly-resolving the elastically scattered light, features can be detected in these patterns that are sensitive to a particle's morphology (shape, size, internal structure, and composition). An apparatus to collect LA TAOS (Large-Angle Two-dimensional Angular Optical Scattering) patterns from single particles in-situ and in real-time was designed and constructed. The setup utilizes a cross-beam trigger system to minimize the effects of the aberration coma stemming from the main collection optic, an ellipsoidal mirror. LA TAOS patterns of ambient aerosols were collected and analyzed. Approximately 15% of the ambient aerosol had a sphere-like shape. The refractive index of these spheres was estimated by curve-fitting to Lorenz-Mie theory. In addition, the island features prevalent in the LA TAOS pattern were analyzed. Metrics generated from these were used to get partial discrimination between clusters of Bacillus subtilis spores (a simulant for anthrax) and aerosol particles found in the ambient atmosphere. A novel experimental setup for collecting simultaneously LA TAOS patterns at two wavelengths in the mid-infrared was also implemented. With this setup, the relative strength of single-particle absorption could be discerned at the two illuminating wavelengths.
Low Energy Analyzing Powers in Pion-Proton Elastic Scattering
Meier, R; Bilger, R; Van den Brandt, B; Breitschopf, J; Clement, H; Comfort, J R; Denz, H; Erhardt, A; Föhl, K; Friedman, E; Gr"ater, J; Hautle, P; Hofman, G J; Konter, J A; Mango, S; P"atzold, J; Pavan, M M; Wagner, G J; Von Wrochem, F
2004-01-01
Analyzing powers of pion-proton elastic scattering have been measured at PSI with the Low Energy Pion Spectrometer LEPS as well as a novel polarized scintillator target. Angular distributions between 40 and 120 deg (c.m.) were taken at 45.2, 51.2, 57.2, 68.5, 77.2, and 87.2 MeV incoming pion kinetic energy for pi+ p scattering, and at 67.3 and 87.2 MeV for pi- p scattering. These new measurements constitute a substantial extension of the polarization data base at low energies. Predictions from phase shift analyses are compared with the experimental results, and deviations are observed at low energies.
Four-body dynamics in 6Li elastic scattering
Watanabe, Shin; Ogata, Kazuyuki; Yahiro, Masanobu
2015-01-01
We analyze 6Li elastic scattering in a wide range of incident energies (Ein), assuming the n + p + alpha + target four-body model and solving the dynamics with the four-body version of the continuum-discretized coupled-channels method (CDCC). Four-body CDCC well reproduces the experimental data with no adjustable parameter for 6Li + 209Bi scattering at Ein = 24-50 MeV and 6Li + 208Pb scattering at Ein = 29-210 MeV. In the wide Ein range, 6Li breakup is significant and provides repulsive corrections to the folding potential. As an interesting property, d breakup is strongly suppressed in 6Li-breakup processes independently of Ein. We investigate what causes the d-breakup suppression.
Elastic wave scattering to characterize heterogeneities in the borehole environment
Tang, Xiao-Ming; Li, Zhen; Hei, Chuang; Su, Yuan-Da
2016-04-01
Scattering due to small-scale heterogeneities in the rock formation surrounding a wellbore can significantly change the acoustic waveform from a logging measurement which in turn can be used to characterize the formation heterogeneities. This study simulates the elastic heterogeneity scattering in monopole and dipole acoustic logging and analyse the resulting effects on the waveforms. The results show that significant coda waves are generated in both monopole and dipole waveforms and the dipole coda is dominated by S-to-S scattering, which can be effectively utilized to diagnose the heterogeneity in the rock formation. The coda wave modelling and analysis were used to characterize dipole acoustic data logged before and after fracturing a reservoir interval, with significant coda wave in the after-fracturing data indicating fracturing-induced heterogeneous property change in the rock volume surrounding the borehole.
Low energy analyzing powers in pion-proton elastic scattering
Meier, R.; Cröni, M.; Bilger, R.; van den Brandt, B.; Breitschopf, J.; Clement, H.; Comfort, J. R.; Denz, H.; Erhardt, A.; Föhl, K.; Friedman, E.; Gräter, J.; Hautle, P.; Hofman, G. J.; Konter, J. A.; Mango, S.; Pätzold, J.; Pavan, M. M.; Wagner, G. J.; von Wrochem, F.
2004-05-01
Analyzing powers of pion-proton elastic scattering have been measured at PSI with the Low Energy Pion Spectrometer LEPS and a novel polarized scintillator target. Angular distributions between 40 and 120 deg (c.m.) were taken at 45.2, 51.2, 57.2, 68.5, 77.2, and 87.2 MeV incoming pion kinetic energy for π+p scattering, and at 67.3 and 87.2 MeV for π-p scattering. These new measurements constitute a substantial extension of the polarization data base at low energies. Predictions from phase shift analyses are compared with the experimental results, and deviations are observed at low energies.
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...
Effect of the Pauli principle in elastic scattering
Picklesimer, A.; Thaler, R. M.
1981-01-01
The effect of imposition of the Pauli principle for two-fragment elastic nuclear scattering is examined. It is shown that the antisymmetrized problem can be cast into the Lippmann-Schwinger form with an effective interaction in which the effect of the Pauli principle is entirely absorbed into the effective interaction potential operator. This result enables the formalism to be developed in analogy with the unsymmetrized formulation. Central to the approach is the choice of the off-shell extension of the transition operator. Comparison is made with a previously proposed treatment based on a different off-shell extension. It is shown that both the antisymmetrized transition operator and the associated optical potential proposed herein are readily expressed as spectator expansions in which the effect of the Pauli principle among the active fermions is incorporated in a physically appealing fashion at each stage of the expansion. NUCLEAR REACTIONS Antisymmetrization incorporated in elastic scattering and optical potential theory. Multiple scattering series and spectator expansion.
Angular distribution of 6He+p elastic scattering
LIU Xin; SU Jun; ZENG Sheng; YAN Sheng-Quan; LIAN Gang; HUANG Wu-Zhen; LIU Wei-Ping; WANG You-Bao; LI Zhi-Hong; JIN Sun-Jun; WANG Bao-Xiang; LI Yun-Ju; LI Er-Tao; BAI Xi-Xiang; GUO Bing
2012-01-01
The angular distribution of 1H(6He,p)6He elastic scattering has been measured at Ec.m.=4.3 MeV by using a thick-target inverse kinematic method.The experimental differential cross sections are reproduced by the distorted-wave Born approximation calculation utilizing the CH89 global optical potential parameter set.The real part of CH89 is reduced comparing with other potentials,which may be attributed to the couplings necessary for the weakly bound nuclei.
Electron and proton elastic scattering in water vapour
Champion, C., E-mail: champion@univ-metz.fr [Universite Paul Verlaine-Metz, Laboratoire de Physique Moleculaire et des Collisions, 1 Boulevard Arago, Technopole 2000, 57078 Metz (France); Universite Bordeaux 1, CNRS/IN2P3, Centre d' Etudes Nucleaires de Bordeaux Gradignan, CENBG, Chemin du Solarium, BP120, 33175 Gradignan (France); Incerti, S.; Tran, H.N. [Universite Bordeaux 1, CNRS/IN2P3, Centre d' Etudes Nucleaires de Bordeaux Gradignan, CENBG, Chemin du Solarium, BP120, 33175 Gradignan (France); El Bitar, Z. [Institut Pluridisciplinaire Hubert Curien, 23 rue du Loess, BP28, 67037 Strasbourg, Cedex 2 (France)
2012-02-15
In the present work, we report theoretical differential and integrated cross sections of the elastic scattering process for sub-thermalization electrons (E{sub inc} {approx_equal} 10 meV-10 keV) and 1 keV-1 MeV protons in water vapour. The calculations are performed within the quantum mechanical framework for electrons whereas classical calculations are provided for protons. The results obtained in this free-parameter theoretical treatment are compared to available data and quantitative differences are reported.
Relativistic effects in neutron-deuteron elastic scattering
Witala, H; Glöckle, W; Kamada, H
2004-01-01
We solved the three-nucleon Faddeev equation including relativistic features such as relativistic kinematics, boost effects and Wigner spin rotations. As dynamical input a relativistic nucleon-nucleon interaction exactly on-shell equivalent to the AV18 potential has been used. The effects of Wigner rotations for elastic scattering observables were found to be small. The boost effects are significant at higher energies.They diminish the transition matrix elements at higher energies and lead in spite of the increased relativistic phase-space factor as compared to the nonrelativistic one to rather small effects in the cross section, which are mostly restricted to the backward angles.
Tensor analyzing power in πd elastic scattering
Smith, G. R.; Altman, A.; Delheij, P.; Gill, D. R.; Healey, D.; Johnson, R. R.; Jones, G.; Ottewell, D.; Rozon, F. M.; Sevior, M. E.; Tervisidis, F.; Trelle, R. P.; Wait, G. D.; Walden, P.; Mathie, E. L.; Lolos, G. J.; Naqvi, S. I.; Boschitz, E. T.; Ottermann, C. R.; Kyle, G. S.; Amaudruz, P. A.
1986-08-01
A tensor-polarized deuteron target has been employed for the first measurements of the tensor analyzing power, T20, in πd elastic scattering. Data at six angles were measured at pion bombarding energies of 133.8 and 150.9 MeV. The results settle a long-standing controversy over conflicting measurements of the tensor polarization t20, and dispute evidence for dibaryon resonances predicated on one of these t20 measurements. The data are shown to be in reasonable agreement with recent Faddeev calculations which have reduced contributions from pion absorption.
ANALYSIS ON ACOUSTICAL SCATTERING BY A CRACKED ELASTIC STRUCTURE
ZhongWeffang; WuYongdong; WuGuorong; LiangYide
2003-01-01
The acoustical scattering by a cracked elastic structure is studied. The mixed method of boundary element and fractal finite element is adopted to solve the cracked structure-acoustic coupling problem. The fractal two-level finite element method is employed for the cracked structure, which can reduce the degree of freedoms (DOFs) greatly, and the boundary element method is used for the exterior acoustic field which can automatically satisfy Sommerfeld's radiation condition. Numerical examples show that the resonance frequency is lower with the crack's depth increase, and that the effect on the acoustical field by the crack is particularly pronounced in the vicinity of the crack tip. This mixed method of boundary element and finite element is effective in solving the scattering problem by a cracked structure.
Elastic Electron Scattering from Tritium and Helium-3
Collard, H.; Hofstadter, R.; Hughes, E. B.; Johansson, A.; Yearian, M. R.; Day, R. B.; Wagner, R. T.
1964-10-01
The mirror nuclei of tritium and helium-3 have been studied by the method of elastic electron scattering. Absolute cross sections have been measured for incident electron energies in the range 110 - 690 MeV at scattering angles lying between 40 degrees and 135 degrees in this energy range. The data have been interpreted in a straightforward manner and form factors are given for the distributions of charge and magnetic moment in the two nuclei over a range of four-momentum transfer squared 1.0 - 8.0 F{sup -2}. Model-independent radii of the charge and magnetic moment distributions are given and an attempt is made to deduce form factors describing the spatial distribution of the protons in tritium and helium-3.
Proton polarizability contribution: Muonic hydrogen Lamb shift and elastic scattering
Miller, Gerald A., E-mail: miller@phys.washington.edu [Department of Physics, Univ. of Washington, Seattle, WA 98195-3560 (United States)
2013-01-08
The uncertainty in the contribution to the Lamb shift in muonic hydrogen, {Delta}E{sup subt} arising from proton polarizability effects in the two-photon exchange diagram at large virtual photon momenta is shown large enough to account for the proton radius puzzle. This is because {Delta}E{sup subt} is determined by an integrand that falls very slowly with very large virtual photon momenta. We evaluate the necessary integral using a set of chosen form factors and also a dimensional regularization procedure which makes explicit the need for a low energy constant. The consequences of our two-photon exchange interaction for low-energy elastic lepton-proton scattering are evaluated and could be observable in a planned low energy lepton-proton scattering experiment planned to run at PSI.
Hybrid Modeling of Elastic Wave Scattering in a Welded Cylinder
Mahmoud, A.; Shah, A. H.; Popplewell, N.
2003-03-01
In the present study, a 3D hybrid method, which couples the finite element region with guided elastic wave modes, is formulated to investigate the scattering by a non-axisymmetric crack in a welded steel pipe. The algorithm is implemented on a parallel computing platform. Implementation is facilitated by the dynamic memory allocation capabilities of Fortran 90™ and the parallel processing directives of OpenMp™. The algorithm is validated against available numerical results. The agreement with a previous 2D hybrid model is excellent. Novel results are presented for the scattering of the first longitudinal mode from different non-axisymmetric cracks. The trend of the new results is consistent with the previous findings for the axisymmetric case. The developed model has potential application in ultrasonic nondestructive evaluation of welded steel pipes.
(-p)p and pp Elastic Scattering at High Energies
无
2007-01-01
Based on the eikonalized Glauber representation of hadron-hadron scattering, we study the diffractive processes of -pp and pp elastic scattering at high energies. From our theoretical calculations and fits to the corresponding experimental data at high energies and all available momentum transfer, we find that the Pomeron exchange contributions play a significant role in description of differential cross section dσ/dt in the whole experimental domain. The Pomeron exchange contributions are related to multi-gluon exchanges in QCD, which are color singlet bound state of Reggeized gluons, such as tensor glueball and Odderon. Accordingly, we may claim that the -pp and pp diffractive processes at high energies s and moderate momentum transfer t would be a good tool to verify the existence of the color singlet multigluon bound states and to test QCD since QCD theory does predict the existence of these states. Therefore, we believe that the experimental measurement should be done for these diffractive processes.
Form factor ratio from unpolarized elastic electron-proton scattering
Pacetti, Simone; Tomasi-Gustafsson, Egle
2016-11-01
A reanalysis of unpolarized electron-proton elastic scattering data is done in terms of the electric to magnetic form factor squared ratio. This observable is in principle more robust against experimental correlations and global normalizations. The present analysis shows indeed that it is a useful quantity that contains reliable and coherent information. The comparison with the ratio extracted from the measurement of the longitudinal to transverse polarization of the recoil proton in polarized electron-proton scattering shows that the results are compatible within the experimental errors. Limits are set on the kinematics where the physical information on the form factors can be safely extracted. The results presented in this work bring a decisive piece of information to the controversy on the deviation of the proton form factors from the dipole dependence.
Photon elastic scattering simulation: validation and improvements to Geant4
Batic, Matej; Pia, Maria Grazia; Saracco, Paolo
2012-01-01
Several models for the simulation of photon elastic scattering are quantitatively evaluated with respect to a large collection of experimental data retrieved from the literature. They include models based on the form factor approximation, on S-matrix calculations and on analytical parameterizations; they exploit publicly available data libraries and tabulations of theoretical calculations. Some of these models are currently implemented in general purpose Monte Carlo systems; some have been implemented and evaluated for the first time in this paper for possible use in Monte Carlo particle transport. The analysis mainly concerns the energy range between 5 keV and a few MeV. The validation process identifies the newly implemented model based on second order S-matrix calculations as the one best reproducing experimental measurements. The validation results show that, along with Rayleigh scattering, additional processes, not yet implemented in Geant4 nor in other major Monte Carlo systems, should be taken into acc...
Parity Violation in Forward Angle Elastic Electron-Proton Scattering
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.
Benchmark calculations for elastic fermion-dimer scattering
Bour, Shahin; Lee, Dean; Meißner, Ulf-G
2012-01-01
We present continuum and lattice calculations for elastic scattering between a fermion and a bound dimer in the shallow binding limit. For the continuum calculation we use the Skorniakov-Ter-Martirosian (STM) integral equation to determine the scattering length and effective range parameter to high precision. For the lattice calculation we use the finite-volume method of L\\"uscher. We take into account topological finite-volume corrections to the dimer binding energy which depend on the momentum of the dimer. After subtracting these effects, we find from the lattice calculation kappa a_fd = 1.174(9) and kappa r_fd = -0.029(13). These results agree well with the continuum values kappa a_fd = 1.17907(1) and kappa r_fd = -0.0383(3) obtained from the STM equation. We discuss applications to cold atomic Fermi gases, deuteron-neutron scattering in the spin-quartet channel, and lattice calculations of scattering for nuclei and hadronic molecules at finite volume.
pp Elastic Scattering at LHC in Near Forward Direction
Islam, M M; Prokudin, A V
2004-01-01
We predict pp elastic differential cross section at LHC at the c.m. energy sqrt(s) = 14 TeV and momentum transfer range |t| = 0 - 10 GeV^2, which is planned to be measured by the TOTEM group. The field theory model underlying our phenomenological investigation describes the nucleon as a composite object with an outer cloud of quark-antiquark condensate, an inner core of topological baryonic charge, and a still smaller quark-bag of valence quarks. The model satisfactorily describes the asymptotic behavior of total cross section as a function of s and the real to imaginary ratio of the forward scattering amplitude as a function of s. It also describes well the the measured antiproton-proton elastic differential cross sections at sqrt(s)= 546 GeV, 630 GeV, and 1.8 TeV. The large |t| elastic amplitude of the model incorporates the BFKL Pomeron in next to leading order approximation, the perturbative dimensional counting behavior, and the confinement of valence quarks in a small region within the nucleon.
Two photon exchange in elastic electron-nucleon scattering
Peter Blunden; Wolodymyr Melnitchouk; John Tjon
2005-06-01
A detailed study of two-photon exchange in unpolarized and polarized elastic electron-nucleon scattering is presented, taking particular account of nucleon finite size effects. Contributions from nucleon elastic intermediate states are found to have a strong angular dependence, which leads to a partial resolution of the discrepancy between the Rosenbluth and polarization transfer measurements of the proton electric to magnetic form factor ratio. The two-photon exchange contribution to the longitudinal polarization transfer ratio P{sub L} is small, whereas the contribution to the transverse polarization transfer ratio P{sub T} is enhanced at backward angles by several percent, increasing with Q{sup 2}. This gives rise to a several percent enhancement of the polarization transfer ratio P{sub T}/P{sub l} at large Q{sup 2} and backward angles. We compare the two-photon exchange effects with data on the ratio of e{sup +p} to e{sup -p} cross sections, which is predicted to be enhanced at backward angles. Finally, we evaluate the corrections to the form factors of the neutron, and estimate the elastic intermediate state contribution to the {sup 3}He form factors.
De Oliveira Santos, F. [Grand Accelerateur National d' Ions Lourds, UMR 6415, 14 - Caen (France)
2007-07-01
Nuclear reactions can occur at low kinetic energy. Low-energy reactions are characterized by a strong dependence on the structure of the compound nucleus. It turns out that it is possible to study the nuclear structure by measuring these reactions. In this course, three types of reactions are treated: Resonant Elastic Scattering (such as N{sup 14}(p,p)N{sup 14}), Inelastic Scattering (such as N{sup 14}(p,p')N{sup 14*}) and Astrophysical reactions (such as N{sup 14}(p,{gamma})O{sup 15}). (author)
Relativistic (Dirac equation) effects in microscopic elastic scattering calculations
Hynes, M. V.; Picklesimer, A.; Tandy, P. C.; Thaler, R. M.
1985-04-01
A simple relativistic extension of the first-order multiple scattering mechanism for the optical potential is employed within the context of a Dirac equation description of elastic nucleon-nucleus scattering. A formulation of this problem in terms of a momentum-space integral equation displaying an identifiable nonrelativistic sector is described and applied. Extensive calculations are presented for proton scattering from 40Ca and 16O at energies between 100 and 500 MeV. Effects arising from the relativistic description of the propagation of the projectile are isolated and are shown to be responsible for most of the departures from typical nonrelativistic (Schrödinger) results. Off-shell and nonlocal effects are included and these, together with uncertainties in the nuclear densities, are shown not to compromise the characteristic improvement of forward angle spin observable predictions provided by the relativistic approach. The sensitivity to ambiguities in the Lorentz scalar and vector composition of the optical potential is displayed and discussed.
Relativistic (Dirac equation) effects in microscopic elastic scattering calculations
Hynes, M.V.; Picklesimer, A.; Tandy, P.C.; Thaler, R.M.
1985-04-01
A simple relativistic extension of the first-order multiple scattering mechanism for the optical potential is employed within the context of a Dirac equation description of elastic nucleon-nucleus scattering. A formulation of this problem in terms of a momentum-space integral equation displaying an identifiable nonrelativistic sector is described and applied. Extensive calculations are presented for proton scattering from /sup 40/Ca and /sup 16/O at energies between 100 and 500 MeV. Effects arising from the relativistic description of the propagation of the projectile are isolated and are shown to be responsible for most of the departures from typical nonrelativistic (Schroedinger) results. Off-shell and nonlocal effects are included and these, together with uncertainties in the nuclear densities, are shown not to compromise the characteristic improvement of forward angle spin observable predictions provided by the relativistic approach. The sensitivity to ambiguities in the Lorentz scalar and vector composition of the optical potential is displayed and discussed.
Effect of the Pauli principle in elastic scattering
Picklesimer, A.; Thaler, R.M.
1981-01-01
The effect of imposition of the Pauli principle for two-fragment elastic nuclear scattering is examined. It is shown that the antisymmetrized problem can be cast into the Lippmann-Schwinger form with an effective interaction in which the effect of the Pauli principle is entirely absorbed into the effective interaction potential operator. This result enables the formalism to be developed in analogy with the unsymmetrized formulation. Central to the approach is the choice of the off-shell extension of the transition operator. Comparison is made with a previously proposed treatment based on a different off-shell extension. It is shown that both the antisymmetrized transition operator and the associated optical potential proposed herein are readily expressed as spectator expansions in which the effect of the Pauli principle among the active fermions is incorporated in a physically appealing fashion at each stage of the expansion.
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.
Elastic scattering, fusion, and breakup of light exotic nuclei
Kolata, J.J. [University of Notre Dame, Physics Department, Notre Dame, IN (United States); Guimaraes, V. [Universidade de Sao Paulo, Instituto de Fisica, Sao Paulo, SP (Brazil); Aguilera, E.F. [Instituto Nacional de Investigaciones Nucleares, Departamento de Aceleradores, Mexico, Distrito Federal (Mexico)
2016-05-15
The present status of fusion reactions involving light (A< 20) radioactive projectiles at energies around the Coulomb barrier (E<10 MeV per nucleon) is reviewed, emphasizing measurements made within the last decade. Data on elastic scattering (providing total reaction cross section information) and breakup channels for the involved systems, demonstrating the relationship between these and the fusion channel, are also reviewed. Similarities and differences in the behavior of fusion and total reaction cross section data concerning halo nuclei, weakly-bound but less exotic projectiles, and strongly-bound systems are discussed. One difference in the behavior of fusion excitation functions near the Coulomb barrier seems to emerge between neutron-halo and proton-halo systems. The role of charge has been investigated by comparing the fusion excitation functions, properly scaled, for different neutron- and proton-rich systems. Possible physical explanations for the observed differences are also reviewed. (orig.)
Elastic proton-deuteron scattering at intermediate energies
Ramazani-Moghaddam-Arani, A; Bacher, A D; Bailey, C D; Biegun, A; Eslami-Kalantari, M; GaÅ¡pariÄ, 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
2008-01-01
Observables in elastic proton-deuteron scattering are sensitive probes of the nucleon-nucleon interaction and three-nucleon force effects. The present experimental data base for this reaction is large, but contains a large discrepancy between data sets for the differential cross section taken at 135 MeV/nucleon by two experimental research groups. This paper reviews the background of this problem and presents new data taken at KVI. Differential cross sections and analyzing powers for the $^{2}{\\rm H}(\\vec p,d){p}$ and ${\\rm H}(\\vec d,d){p}$ reactions at 135 MeV/nucleon and 65 MeV/nucleon, respectively, have been measured. The data differ significantly from previous measurements and consistently follow the energy dependence as expected from an interpolation of published data taken over a large range at intermediate energies.
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.; Gašparić, 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.
2008-07-01
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 MeV/nucleon by two experimental research groups. This article reviews the background of this problem and presents new data taken at Kernfysisch Versneller Instituute (KVI). Differential cross sections and analyzing powers for the 2H(p→,d)p and 1H(d→,d)p reactions at 135 MeV/nucleon and 65 MeV/nucleon, respectively, have been measured. The differential cross-section data differ significantly from previous measurements and consistently follow the energy dependence as expected from an interpolation of published data taken over a large range at intermediate energies.
Application of multiple scattering theory to lower-energy elastic nucleon-nucleus scattering
Chinn, C.R.; Elster, C.; Thaler, R.M.; Weppner, S.P. (Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235 (United States) Center for Computationally Intensive Physics, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States) Institute of Nuclear Particle Physics, and Department of Physics, Ohio University, Athens, Ohio 45701 (United States) Physics Department, Case Western Reserve University, Cleveland, Ohio 44106 (United States))
1995-03-01
The optical model potentials for nucleon-nucleus elastic scattering at 65 meV are calculated for [sup 12]C, [sup 16]O, [sup 28]Si, [sup 40]Ca, [sup 56]Fe, [sup 90]Zr, and [sup 208]Pb in first-order multiple scattering theory, following the prescription of the spectator expansion, where the only inputs are the free nucleon-nucleon (NN) potentials, the nuclear densities, and the nuclear mean field as derived from microscopic nuclear structure calculations. These potentials are used to predict differential cross sections, analyzing powers, and spin rotation functions for neutron and proton scattering at 65 MeV projectile energy and compared with available experimental data. The theoretical curves are in very good agreement with the data. The modification of the propagator due to the coupling of the struck nucleon to the residual nucleus is seen to be significant at this energy and invariably improves the congruence of theoretical prediction and measurement.
Application of multiple scattering theory to lower-energy elastic nucleon-nucleus scattering
Chinn, C. R.; Elster, Ch.; Thaler, R. M.; Weppner, S. P.
1995-03-01
The optical model potentials for nucleon-nucleus elastic scattering at 65 meV are calculated for 12C, 16O, 28Si, 40Ca, 56Fe, 90Zr, and 208Pb in first-order multiple scattering theory, following the prescription of the spectator expansion, where the only inputs are the free nucleon-nucleon (NN) potentials, the nuclear densities, and the nuclear mean field as derived from microscopic nuclear structure calculations. These potentials are used to predict differential cross sections, analyzing powers, and spin rotation functions for neutron and proton scattering at 65 MeV projectile energy and compared with available experimental data. The theoretical curves are in very good agreement with the data. The modification of the propagator due to the coupling of the struck nucleon to the residual nucleus is seen to be significant at this energy and invariably improves the congruence of theoretical prediction and measurement.
Scattering phase shift for elastic two pion scattering and the rho resonance in lattice QCD
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.
Weakly interacting massive particle-nucleus elastic scattering response
Anand, Nikhil; Fitzpatrick, A. Liam; Haxton, W. C.
2014-06-01
Background: A model-independent formulation of weakly interacting massive particle (WIMP)-nucleon scattering was recently developed in Galilean-invariant effective field theory. Purpose: Here we complete the embedding of this effective interaction in the nucleus, constructing the most general elastic nuclear cross section as a factorized product of WIMP and nuclear response functions. This form explicitly defines what can and cannot be learned about the low-energy constants of the effective theory—and consequently about candidate ultraviolet theories of dark matter—from elastic scattering experiments. Results: We identify those interactions that cannot be reliably treated in a spin-independent/spin-dependent (SI/SD) formulation: For derivative- or velocity-dependent couplings, the SI/SD formulation generally mischaracterizes the relevant nuclear operator and its multipolarity (e.g., scalar or vector) and greatly underestimates experimental sensitivities. This can lead to apparent conflicts between experiments when, in fact, none may exist. The new nuclear responses appearing in the factorized cross section are related to familiar electroweak nuclear operators such as angular momentum l⃗(i) and the spin-orbit coupling σ⃗(i).l⃗(i). Conclusions: To unambiguously interpret experiments and to extract all of the available information on the particle physics of dark matter, experimentalists will need to (1) do a sufficient number of experiments with nuclear targets having the requisite sensitivities to the various operators and (2) analyze the results in a formalism that does not arbitrarily limit the candidate operators. In an appendix we describe a code that is available to help interested readers implement such an analysis.
Nuclear isospin mixing and elastic parity-violating electron scattering
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.
The recoil proton polarization in. pi. p elastic scattering
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.
ELRADGEN: Monte Carlo generator for radiative events in elastic electron-proton scattering
Afanasiev, A V; Ilyichev, A N; Niczyporuk, B B
2003-01-01
We discuss the theoretical approach and practical algorithms for simulation of radiative events in elastic ep-scattering. A new Monte Carlo generator for real photon emission events in the process of elastic electron-proton scattering is presented. We perform a few consistency checks and present numerical results.
Morcelle, V.; Lichtenthäler, R.; Lépine-Szily, A.; Guimarães, V.; Pires, K. C. C.; Lubian, J.; Mendes Junior, D. R.; de Faria, P. N.; Kolata, J. J.; Becchetti, F. D.; Jiang, H.; Aguilera, E. F.; Lizcano, D.; Martinez-Quiroz, E.; Garcia, H.
2017-01-01
We present 8B 27Al elastic scattering angular distributions for the proton-halo nucleus 8B at two energies above the Coulomb barrier, namely Elab=15.3 and 21.7 MeV. The experiments were performed in the Radioactive Ion Beams in Brasil facility (RIBRAS) in São Paulo, and in the TwinSol facility at the University of Notre Dame, USA. The angular distributions were measured in the angular range of 15-80 degrees. Optical model and continuum discretized coupled channels calculations were performed, and the total reaction cross sections were derived. A comparison of the 8B+27Al total reaction cross sections with similar systems including exotic, weakly bound, and tightly bound projectiles impinging on the same target is presented.
Two-photon exchange corrections in elastic electron-proton scattering
Tomalak, O
2016-01-01
We apply a subtracted dispersion relation (DR) formalism with the aim to improve predictions for the two-photon exchange (TPE) corrections to elastic electron-proton scattering observables at small momentum transfers. We study the formalism on the elastic TPE contribution in comparison with existing data for unpolarized cross sections. We extend the general formalism of TPE to elastic scattering with massive lepton and perform a numerical estimate of the muon-proton scattering at low momentum transfer in view of the upcoming muon-proton scattering experiment (MUSE). We study the influence of the double-virtual Compton scattering (VVCS) subtraction function on the unpolarized lepton-proton scattering cross-section. We show that the resulting TPE correction is negligible in the electron-proton scattering and smaller than planned uncertainties of the MUSE experiment for the subtraction functions evaluated in chiral perturbation theory.
Duda, G; Kemper, A; Duda, Gintaras; Gondolo, Paolo; Kemper, Ann
2006-01-01
Theoretical calculations of neutralino cross sections with various nuclei are of great interest to direct dark matter searches such as CDMS, EDELWEISS, ZEPLIN, and other experiments. These cross sections and direct detection rates are generally computed with standard, one or two parameter model-dependent nuclear form factors, which may not exactly mirror the actual form factor for the particular nucleus in question. As is well known, elastic electron scattering can allow for very precise determinations of nuclear form factors and hence nuclear charge densities for spherical or near-spherical nuclei. We use charge densities derived from elastic electron scattering data to calculate model independent form factors for various target nuclei important in dark matter searches, such as Si, Ge, S, Ca and others. We have found that for nuclear recoils in the range of 1-100 keV significant differences in cross sections and rates exist when the model independent form factors are used. DarkSUSY, a publicly-available adva...
Measurement of elastic muon-neutrino scattering off protons
Faissner, Helmut; Bobisut, F; De Witt, H; Frenzel, F; Hansl, T; Hoffmann, D; Huzita, H; Loreti, M; Puglierin, G; Radermacher, E; Reithler, H; Samm, U
1980-01-01
Single recoil protons have been detected in a multiplate Al spark chamber exposed to the 2-GeV wideband neutrino beam from the CERN proton synchrotron. Neutron-induced protons were suppressed by suitable geometrical and kinematical cuts. After correction for remaining neutron background (110+or-15 events) and single-pion contribution (45+or-6 events), the final sample contains 62+or-19 genuine neutrino-induced single protons. This yields an effective ratio of neutral-current (NC) to charged-current (CC) events of R/sub N/=(15+or-5)%, in the range 0.2<-q/sup 2/<1.0 (GeV/c)/sup 2/. This number is due to a mixture of elastic neutrino scatterings off protons and neutrons. From the probability f/sub np/ for a recoil neutron to give an accepted proton, one derives a model-independent combination of the NC/CC ratios R/sub p/+f/sub np/R/sub n/, with f/sub np /=0.31+or-0.04. This favors axial-vector-isovector-dominant NC coupling constants and is consistent with the Weinberg-Salam model with sin/sup 2/ theta /su...
PROTON-4He Elastic Scattering at ~ 1 GeV
Khan, Z. A.; Singh, Minita
Based on the (spin-independent) Sugar-Blanckenbecler eikonal expansion for the T-matrix, we parametrize the (spin-dependent) NN amplitude (SNN) which successfully describes the pp and pn elastic scattering observables at ~ 1 GeV up to the available momentum transfers. Using SNN, we calculate the differential cross-section, polarization, and spin-rotation function of ~ 1 GeV protons on 4He within the framework of the Glauber model. The analysis also includes the phase variation in the NN amplitude. It is found that the use of SNN, in comparision with the usually parametrized one-term amplitude, improves the agreement with the experimental data. The introduction of a global phase variation provides only a slight improvement over the results with a constant phase. However, if we allow different phases in the central- and spin-dependent parts of the NN amplitude, the agreement with the polarization data improves further without affecting the differential cross-section results.
Elastic Wave Scattering by Two-Dimensional Periodical Array of Cylinders
无
2002-01-01
We extend the multiple-scattering theory (MST) for elastic wave scattering and propagating in two-dimensional composite. The formalism for the band structure calculation is presented by taking into account the full vector character of the elastic wave. As a demonstration of application of the formalism, we calculate the band structure of elastic wave propagating in a two-dimensional periodic arrangement of cylinders. The results manifest that the MST shows great promise in complementing the plane-wave (PW) approach for the study of elastic wave.
Probing the $^{6}He$ halo structure with elastic and inelastic proton scattering
Lagoyannis, A; Musumarra, A; Alamanos, N; Pollacco, E C; Pakou, A; Blumenfeld, Y; Braga, F; La Commara, M; Drouart, A; Fioni, G; Gillibert, A; Khan, E U; Lapoux, V; Mittig, W; Ottini-Hustache, S; Pierroutsakou, D; Romoli, M; Roussel-Chomaz, P; Sandoli, M; Santonocito, D; Scarpaci, J A; Sida, J L; Suomijärvi, T; Karataglidis, S; Amos, K A
2001-01-01
Proton elastic scattering and inelastic scattering to the first excited state of 6He have been measured over a wide angular range using a 40.9A MeV 6He beam. The data have been analyzed with a fully microscopic model of proton-nucleus scattering using 6He wave functions generated from large space shell model calculations. The inelastic scattering data show a remarkable sensitivity to the halo structure of 6He.
Generalized Chou-Yang Model and Meson-Proton Elastic Scattering at High Energies
Saleem, Mohammad; Aleem, Fazal-E.; Rashid, Haris
The various characteristics of meson-proton elastic scattering at high energies are explained by using the generalized Chou-Yang model which takes into consideration the anisotropic scattering of objects constituting pions(kaons) and protons. A new parametrization of the proton form factor consistent with the recent experimental data is proposed. It is then shown that all the data for meson-proton elastic scattering at 200 and 250 GeV/c are in agreement with theoretical computations. The physical picture of generalized Chou-Yang model which is based on multiple scattering theory is given in detail.
Generalized Chou-Yang model and meson-proton elastic scattering at high energies
Saleem, M.; Aleem, F.E.; Rashid, H.
1989-01-01
The various characteristics of meson-proton elastic scattering at high energies are explained by using the generalized Chou-Yang model which takes into consideration the anisotropic scattering of objects constituting pions(kaons) and protons. A new parametrization of the proton form factor consistent with the recent experimental data is proposed. It is then shown that all the data for meson-proton elastic scattering at 200 and 250 GeV/c are in agreement with theoretical computations. The physical picture of generalized Chou-Yang model which is based on multiple scattering theory is given in detail.
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
Koutsopoulos, S.; Oost, van der 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
Ivanov, V. Y.; Sipov, N. K.; Shneyder, V. A.
1977-01-01
Analytical representations of the elastic scattering cross sections of electrons with energies of 0.01-1 keV in atmospheric gases of N2, O2, O are given. These representations are suitable for the Monte Carlo method.
The investigation of the Coulomb breakup effect on the 6-He elastic scattering
Kucuk, Yasemin; Boztosun, Ismail [Erciyes University, Department of Physics, Kayseri (Turkey); Keeley, Nicholas [Andrzej Soltan Institute, Department of Nuclear Reactions (Poland)
2009-07-01
The elastic scattering of the halo nuclei from the heavier target exhibits a different behavior from the standart Fresnel-type diffraction at energies near the Coulomb barrier. In this paper, we have performed the CDCC calculations for 6-He elastic scattering from the different targets to investigate the effect of the Coulomb breakup coupling and we have observed that the deviation from the standard diffraction behavior due to strong breakup coupling starts at around ZT= 60.
High Energy Proton-Proton Elastic Scattering in Reggeon-Pomeron Exchange Model
ZHOU Li-Juan; HU Zhao-Hui; MA Wei-Xing
2006-01-01
We initially propose a Reggeon-Pomeron exchange model to describe proton-proton elastic scattering at high energies in this short paper. A calculation for total cross section of proton-proton elastic scattering at high energies is performed without any free parameters. Our new finding from this work is that the Reggeon-Pomeron model gives a perfect fit to experimental data of the total cross section at the whole energy region where experimental data exist.
Measurement of anti pp elastic scattering parameters at radical S=1. 8 TeV
Shukla, S.; Amos, N.A.; Avila, C.; Baker, W.F.; Eartly, D.P.; Gomez, B.; Lennox, A.J.; Negret, J.P.; Pruss, S.M.; Rubinstein, R.; Sanabria, J.C. (Fermi National Accelerator Lab., Batavia, IL (United States)); Bertani, M.; Giacomelli, G.; Mondardini, M.R.; Spagnoli, M.; Veronesi, I.; Zucchelli, S. (Univ. Bologna (Italy) Ist. Nazionale di Fisica Nucleare, Bologna (Italy)); Block, M.M.; Guss, C.M.; Sadr, S. (Northwestern Univ., Evanston, IL (United States)); Dimitroyannis, D.A.; Goodman, J.A. (Univ. Maryland, College Park, MD (United States)); Ellsworth, R.W. (George Mason Univ., Fairfax, VA (United States)); Orear, J. (Cornell Univ., Ithaka, NY (United States)); E710 Collaboration
1992-03-01
A measurement of the total nuclear cross section, {sigma}{sub t}, the ratio of the real to the imaginary part of the forward nuclear elastic scattering amplitude, {rho}, and the nuclear slope parameter, B, for anti pp elastic scattering at {radical}S=1.8 TeV, is presented. We find {sigma}{sub t}=72.8{+-}3.1 mb, {rho}=0.140{+-}.069 and B=16.99{+-}47 (GeV/c){sup -2}. (orig.).
P(P bar)P elastic scattering and cosmic ray data
FAZAL-E-ALEEM; Saleem, M.
1985-01-01
It is shown that the total cross section for pp elastic scattering at cosmic ray energies, as well as the total cross section, the slope parameter b(s,t) and the differential cross section for small momentum transfer at ISR and collider energies for p(p)p elastic scattering can be simultaneously fitted by using a simple Regge pole model. The results of this theory is discussed in detail.
Quark-diquark model for p(\\bar p)-p elastic scattering at high energies
Grichine, V M; Zotov, N P
2012-01-01
A model for elastic scattering of protons at high energies based on the quark-diquark representation of the proton is discussed. The predictions of the model are compared with experimental data for the differential elastic cross-sections from available databases
Quark-diquark model for p(anti p) -p elastic scattering at high energies
Grichine, V.M.; Starkov, N.I. [Lebedev Physical Institute, Moscow (Russian Federation); Zotov, N.P. [Lomonosov Moscow State University, Skobeltsyn Institute of Nuclear Physics, Moscow (Russian Federation)
2013-02-15
A model for elastic scattering of protons at high energies based on the quark-diquark representation of the proton is discussed. The predictions of the model are compared with experimental data for the differential elastic cross-sections from available databases. (orig.)
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.
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.
Strong coupling effects in near-barrier heavy-ion elastic scattering
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
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
Two-photon exchange correction to muon-proton elastic scattering at low momentum transfer
Tomalak, Oleksandr [Johannes Gutenberg Universitaet, Institut fuer Kernphysik, Mainz (Germany); Johannes Gutenberg-Universitaet, PRISMA Cluster of Excellence, Mainz (Germany); Taras Shevchenko National University of Kyiv, Department of Physics, Kiev (Ukraine); Vanderhaeghen, Marc [Johannes Gutenberg Universitaet, Institut fuer Kernphysik, Mainz (Germany); Johannes Gutenberg-Universitaet, PRISMA Cluster of Excellence, Mainz (Germany)
2016-03-15
We evaluate the two-photon exchange (TPE) correction to the muon-proton elastic scattering at small momentum transfer. Besides the elastic (nucleon) intermediate state contribution, which is calculated exactly, we account for the inelastic intermediate states by expressing the TPE process approximately through the forward doubly virtual Compton scattering. The input in our evaluation is given by the unpolarized proton structure functions and by one subtraction function. For the latter, we provide an explicit evaluation based on a Regge fit of high-energy proton structure function data. It is found that, for the kinematics of the forthcoming muon-proton elastic scattering data of the MUSE experiment, the elastic TPE contribution dominates, and the size of the inelastic TPE contributions is within the anticipated error of the forthcoming data. (orig.)
Two-photon exchange correction to muon-proton elastic scattering at small momentum transfer
Tomalak, O
2015-01-01
We evaluate the two-photon exchange (TPE) correction to the muon-proton elastic scattering at small momentum transfer. Besides the elastic (nucleon) intermediate state contribution, which is calculated exactly, we account for the inelastic intermediate states by expressing the TPE process approximately through the forward doubly virtual Compton scattering. The input in our evaluation is given by the unpolarized proton structure functions and by one subtraction function. For the latter, we provide an explicit evaluation based on a Regge fit of high-energy proton structure function data. It is found that,for the kinematics of the forthcoming muon-proton elastic scattering data of the MUSE experiment, the elastic TPE contribution dominates, and the size of the inelastic TPE contributions is within the anticipated error of the forthcoming data.
Unified quantum theory of elastic and inelastic atomic scattering from a physisorbed monolayer solid
Bruch, L. W.; Hansen, Flemming Yssing; Dammann, Bernd
2017-01-01
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...... 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...
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.
Hulth$\\grave{e}$n potential models for $\\alpha−\\alpha$ and $\\alpha−He^3$ elastic scattering
J BHOI; U LAHA
2017-03-01
Simple Hulth$\\grave{e}$n-type potential models are proposed to treat the $\\alpha−\\alpha$ and $\\alpha−He^3$ elastic scattering. The merit of our approach is examined by computing elastic scattering phases through the judicious use of the phase function method. Reasonable agreements in scattering phase shifts are obtained with the standard data.
Hulthén potential models for α-α and α-He 3 elastic scattering
BHOI, J.; LAHA, U.
2017-03-01
Simple Hulthén-type potential models are proposed to treat the α- α and α {-} {He}3 elastic scattering. The merit of our approach is examined by computing elastic scattering phases through the judicious use of the phase function method. Reasonable agreements in scattering phase shifts are obtained with the standard data.
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.
Müller, Christof
2000-01-01
The nature of seismic scattering was investigated by elastic scattering theory and numerical experiment. Seismic scattering situations can be classified by analyzing the amplitude versus scattering angle behavior of the scattered seismic wave field. The shape of large objects has significant impact on the dynamics of the scattered wave field. Gather oriented as well as prestack methods capable of enhancing the scattering response and assisting in classification were developed. A new 3D migrat...
Korda, V Y; Korda, L P
2005-01-01
We present a new procedure which enables to extract a scattering matrix $S(l)$ as a complex function of angular momentum directly from the scattering data, without any a priori model assumptions implied. The key ingredient of the procedure is the evolutionary algorithm with diffused mutation which evolves the population of the scattering matrices, via their smooth deformations, from the primary arbitrary analytical $S(l)$ shapes to the final ones giving high quality fits to the data. Due to the automatic monitoring of the scattering matrix derivatives, the final $S(l)$ shapes are monotonic and do not have any distortions. For the $^{16}$O-$^{16}$O elastic scattering data at 350 MeV, we show the independence of the final results of the primary $S(l)$ shapes. Contrary to the other approaches, our procedure provides an excellent fit by the $S(l)$ shapes which support the ``rainbow'' interpretation of the data under analysis.
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 Dependence of Slope Parameter in Elastic Nucleon-Nucleon Scattering
V. A. Okorokov
2015-01-01
Full Text Available The diffraction slope parameter is investigated for elastic proton-proton and proton-antiproton scattering based on all the available experimental data at low and intermediate momentum transfer values. Energy dependence of the elastic diffraction slope is approximated by various analytic functions. The expanded “standard” logarithmic approximations with minimum number of free parameters allow description of the experimental slopes in all the available energy range reasonably. The estimations of asymptotic shrinkage parameter αP′ are obtained for various |t| domains based on all the available experimental data. Various approximations differ from each other both in the low energy and very high energy domains. Predictions for diffraction slope parameter are obtained for elastic proton-proton scattering from NICA up to future collider (FCC/VLHC energies, for proton-antiproton elastic reaction in FAIR energy domain for various approximation functions.
Szilner, S; Basrak, Z; Freeman, R M; Haas, F; Morsad, A; Brandan, M E; Satchler, G R
2001-01-01
The experimental data on the $^{16}$O$+^{12}$C and $^{18}$O$+^{12}$C elastic scatterings and their optical model analysis are presented. Detailed and complete elastic angular distributions have been measured at the Strasbourg Vivitron accelerator at several energies covering the energy range between 5 and 10 MeV per nucleon. The elastic scattering angular distributions show the usual diffraction pattern and also, at larger angles, refractive effects in the form of nuclear rainbow and associated Airy structures. The optical model analysis unambiguously shows the evolution of the refractive scattering pattern. The observed structure, namely the Airy minima, can be consistently described by a nucleus-nucleus potential with a deep real part and a weakly absorptive imaginary part. The difference in absorption in the two systems is explained by an increased imaginary (mostly surface) part of the potential in the $^{18}$O$+^{12}$C system. The relation between the obtained potentials and those reported for the symmet...
Two-Photon-Exchange Correction to Elastic ep Scattering in the Forward Angle Limit
ZHOU Hai-Qing
2009-01-01
The two-photon-exchange (TPE) correction to elastic ep ecattering in the forward angle region is discussed based on a simple hadronic model.It is found that the correction is exactly zero in the forward angle limit.This analytical result gives a good explanation of the previous numerical results and shows the clear power behavior of the TPE correction to elastic ep scattering in the forward angle region.
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...
Evolution of Elastic X-ray Scattering in Laser-Shocked Warm Dense Li
Kugland, N L; Gregori, G; Bandyopadhyay, S; Brenner, C; Brown, C; Constantin, C; Glenzer, S H; Khattak, F; Kritcher, A L; Niemann, C; Otten, A; Pasley, J; Pelka, A; Roth, M; Spindloe, C; Riley, D
2009-06-02
We have studied the dynamics of warm dense Li with near-elastic x-ray scattering. Li foils were heated and compressed using shock waves driven by 4 ns long laser pulses. Separate 1 ns long laser pulses were used to generate a bright source of 2.96 keV Cl Ly-{alpha} photons for x-ray scattering, and the spectrum of scattered photons was recorded at a scattering angle of 120{sup o} using a HOPG crystal operated in the von Hamos geometry. A variable delay between the heater and backlighter laser beams measured the scattering time evolution. Comparison with radiation hydrodynamics simulations shows that the plasma is highly coupled during the first several nanoseconds, then relaxes to a moderate coupling state at later times. Near-elastic scattering amplitudes have been successfully simulated using the screened one-component plasma model. Our main finding is that the near-elastic scattering amplitudes are quite sensitive to the mean ionization state {bar Z}, and by extension to the choice of ionization model in the radiation-hydrodynamics simulations used to predict plasma properties within the shocked Li.
New measurements and phase shift analysis of p16O elastic scattering at astrophysical energies
Dubovichenko, Sergey; Burtebayev, Nassurlla; Dzhazairov-Kakhramanov, Albert; Zazulin, Denis; Kerimkulov, Zhambul; Nassurlla, Marzhan; Omarov, Chingis; Tkachenko, Alesya; Shmygaleva, Tatyana; Kliczewski, Stanislaw; Sadykov, Turlan
2017-01-01
The results of new experimental measurements of p16O elastic scattering in the energy range of 0.6-1.0 MeV at angles of 40°-160° are given. Phase shift analysis of p16O elastic scattering was made using these and other experimental data on differential cross sections in excitation functions and angular distributions at energies of up to 2.5 MeV. Supported by the Ministry of Education and Science of the Republic of Kazakhstan (0073/PCF-IS-MES)
Surface Diffuseness Anomaly in 16O+208pb Quasi-elastic Scattering at Backward Angle
JIA Hui-Ming; XU Xin-Xing; BAI Chun-Lin; YU Ning; LIN Cheng-Jian; ZHANG Huan-Qiao; LIU Zu-Hua; YANG Feng; JIA Fei; ZHANG Chun-Lei; AN Guang-Peng; WU Zhen-Dong
2008-01-01
@@ The quasi-elastic scattering excitation function of the doubly magic 16O+208pb system at a backward angle is measured at sub-barrier energies with high precision. The diffuseness parameters extracted from both the single-channel and the coupled-channels calculations give almost the same value α = 0.76±0.04 fm. The results show that the coupling effect is negligible for the spherical system. The obtained value is smaller than the extracted value from the fusion excitation function, but larger than the value of α = 0.63 fm, which is from the systematic analysis of elastic scattering data.
K-Nucleus Elastic Scattering and Momentum-Dependent Optical Potentials
ZHONG Xian-Hui; LI Lei; CAI Chong-Hai; NING Ping-Zhi
2004-01-01
The K-nucleus differential elastic scattering cross section for 12C and 40 Ca at pκ = 800 Me V/c is calculated with three momentum-dependent optical potential models,which are density-dependent,relativistic mean field,and hybrid model,respectively.It is found that the forms of momentum-dependent optical potential models proposed by us are reasonable and gain success in the calculations and the momentum-dependent hybrid model is the best model for the K- nucleus elastic scattering.
Probing proton halo of the exotic nucleus 28S by elastic electron scattering
WANG; Zaijun; REN; Zhongzhou
2004-01-01
Elastic electron scattering on the exotic light nucleus 28S is investigated in the plane wave Born approximation. The variation of the squared form factors of 28S with momentum transfer is compared with that of 32S. It is found that the behavior of the form factors near the second minimum (with a moderate momentum transfer) is sensitive to the alteration of the charge density distribution of halo protons in 28S. This indicates that elastic electron scattering can be a good probe of the structure of proton-halo nuclei.
The energy dependence of the diffraction minimum in the elastic scattering and new LHC data
Selyugin, O. V.
2017-03-01
The soft diffraction phenomena in the elastic proton-proton scattering are reviewed from the viewpoint of experiments at the LHC (TOTEM and ATLAS collaboration). In the framework of the High Energy Generalized Structure (HEGS) model the form of the diffraction minimum in the nucleon-nucleon elastic scattering in a wide energy region is analyzed. The energy dependencies of the main characteristics of the diffraction dip are obtained. The numerical predictions at LHC energies are presented. The comparison of the model predictions with the new LHC data at √{ s} = 13 TeV is made.
Influence of the halo upon angular distributions for elastic scattering and breakup
Capel, P., E-mail: capel@nscl.msu.ed [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824 (United States); Physique Quantique, CP 165/82, and Physique Nucleaire Theorique et Physique Mathematique, CP229, Universite Libre de Bruxelles (ULB), B-1050 Brussels (Belgium); Hussein, M.S., E-mail: hussein@if.usp.b [Instituto de Fisica, Universidade de Sao Paulo C.P. 66318, 05315-970 Sao Paulo, S.P. (Brazil); Baye, D., E-mail: dbaye@ulb.ac.b [Physique Quantique, CP 165/82, and Physique Nucleaire Theorique et Physique Mathematique, CP229, Universite Libre de Bruxelles (ULB), B-1050 Brussels (Belgium)
2010-10-11
The angular distributions for elastic scattering and breakup of halo nuclei are analysed using a near-side/far-side decomposition within the framework of the dynamical eikonal approximation. This analysis is performed for {sup 11}Be impinging on Pb at 69 MeV/nucleon. These distributions exhibit very similar features. In particular they are both near-side dominated, as expected from Coulomb-dominated reactions. The general shape of these distributions is sensitive mostly to the projectile-target interactions, but is also affected by the extension of the halo. This suggests the elastic scattering not to be affected by a loss of flux towards the breakup channel.
E710, $p\\bar{p}$ Elastic Scattering at Tevatron Energies
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 of 17O ions from 58Ni at near-barrier energies
Torresi D.; Strano E.; Mazzocco M.; Boiano A.; Boiano C.; Di Meo P.; Guglielmetti A.; La Commara M.; Manea C.; Nicoletto M.; Parascandolo C.; Parascandolo L.; Pierroutsakou D.; Sandoli M.; Signorini C.
2014-01-01
Elastic scattering has been studied for the collisions induced by 17O on 58Ni target at energies around and above the Coulomb barrier. The elastic scattering angular distributions were measured for several energies and were analyzed within the framework of the optical model to obtain total reaction cross sections. The reaction cross-sections of the tightly bound 17O were compared with those of weakly bound 17F on the same targets in order to investigate the effects of the low binding energy i...
Elastic scattering of 17O ions from 58Ni at near-barrier energies
Torresi D.
2014-03-01
Full Text Available Elastic scattering has been studied for the collisions induced by 17O on 58Ni target at energies around and above the Coulomb barrier. The elastic scattering angular distributions were measured for several energies and were analyzed within the framework of the optical model to obtain total reaction cross sections. The reaction cross-sections of the tightly bound 17O were compared with those of weakly bound 17F on the same targets in order to investigate the effects of the low binding energy in the reaction dynamics.
Elastic scattering of 17O ions from 58Ni at near-barrier energies
Torresi, D.; Strano, E.; Mazzocco, M.; Boiano, A.; Boiano, C.; Di Meo, P.; Guglielmetti, A.; La Commara, M.; Manea, C.; Nicoletto, M.; Parascandolo, C.; Parascandolo, L.; Pierroutsakou, D.; Sandoli, M.; Signorini, C.; Soramel, F.; Toniolo, N.; Grebosz, J.; Filipescu, D.; Gheorghe, A.; Glodariu, T.; Stroe, L.; Miyatake, H.; Watanabe, Y.; Jeong, S.; Kim, Y. H.; Pakou, A.; Sgouros, O.; Soukeras, V.; Zerva, K.
2014-03-01
Elastic scattering has been studied for the collisions induced by 17O on 58Ni target at energies around and above the Coulomb barrier. The elastic scattering angular distributions were measured for several energies and were analyzed within the framework of the optical model to obtain total reaction cross sections. The reaction cross-sections of the tightly bound 17O were compared with those of weakly bound 17F on the same targets in order to investigate the effects of the low binding energy in the reaction dynamics.
High Energy (-p)p and pp Elastic Scatterings in QCD Inspired Model
LU Juan; MA Wei-Xing; HE Xiao-Rong
2007-01-01
We propose QCD inspired model to calculate (p)p and pp elastic scatterings at high energies in this paper.A calculation for total cross section of (p)p and pp is performed in which the contributions from gluon-gluon,quark-quark,and gluon-quark interactions are included.Our results show that the QCD inspired model gives a perfect fit to experimental data of total cross section both for (p)p and pp elastic scatterings at the whole energy region where experimental data existed at FNAL and CERN.
Myelin basic protein reduces molecular motions in DMPA, an elastic neutron scattering study
Natali, F.; Gliozzi, A.; Rolandi, R.; Cavatorta, P.; Deriu, A.; Fasano, A.; Riccio, P.
2001-07-01
We have studied the effect of physiological amounts of myelin basic protein (MBP) on pure dimyristoyl L- α-phosphatidic acid (DMPA) vesicles using the elastic neutron scattering technique. Elastic scans have been performed in a wide temperature range (20-300 K). In the lower temperature region the behaviour of the integrated elastic intensity was the typical one of harmonic systems. The analysis of the Q and T dependence performed in terms of an asymmetric double well potential clearly showed that the effect of the protein consisted in a significant reduction of the conformational mobility of the DMPA bilayers and in the stabilisation of the membrane.
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.
Magnetoconductivity of quantum wires with elastic and inelastic scattering
Bruus, Henrik; Flensberg, Karsten; Smith
1993-01-01
We use a Boltzmann equation to determine the magnetoconductivity of quantum wires. The presence of a confining potential in addtion to the magnetic field removes the degeneracy of the Landau levels and allows one to associate a group velocity with each single-particle state. The distribution...... 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...
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 ...
Excitation function of elastic $pp$ scattering from a unitarily extended Bialas-Bzdak model
Nemes, F; Csanád, M
2014-01-01
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}=$8, 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 sma...
Scattering of waves by three-dimensional obstacles in elastic metamaterials with zero index
Liu, Fengming; Zhang, Feng; Wei, Wei; Hu, Ni; Deng, Gang; Wang, Ziyu
2016-12-01
The scattering of elastic waves by three-dimensional obstacles in isotropic elastic zero-index-metamaterials (ZIM) is theoretically investigated. We show that the zero values of each single effective parameter and their various combinations of the elastic ZIM can produce different types of wave propagation. Particularly, there is no mode conversion when either longitudinal (P ) wave or transverse (S ) wave is scattered by the obstacles in a specific type of double-ZIM (DZIM), possessing near zero reciprocal of shear modulus and near zero mass density. When the obstacle is off resonance, elastic waves are scarcely scattered; nevertheless, the scattering cross section of the obstacle can be drastically enhanced by orders of magnitude when it is on resonance. While in another type of DZIM possessing near zero reciprocal of bulk modulus and near zero mass density, mode conversion occurs during the scattering process and many other transmission characteristics are also different to the former. Moreover, enhanced transmission can be realized for various types of single-ZIM (SZIM) by introducing obstacles, and numerical analysis shows that the enhanced transmission is due to resonant modes arisen in the embedded obstacles. We expect that our findings could have potential practical application, such as seismic protection and on-chip phononic devices.
Measurement Of The Cross Section For Elastic Scattering Of Electron Neutrinos On Electrons
Wadia-Neville, D
1998-01-01
In this dissertation, we measure the cross section for the elastic scattering of electron neutrinos on electrons. We use data from the LSND experiment which is located at the Los Alamos Neutron Scattering Center at Los Alamos National Laboratory, New Mexico. The neutrino beam is produced when an 800 MeV proton beam from a linear accelerator is incident on a target located 29.8 m from the detector. The LSND veto system allows us to reject charged cosmic-ray particles entering the detector with high efficiency. The detector consists of 180 tons of mineral oil, to which a small quantity of scintillator is added. This combination enables us to detect both Č erenkov and scintillation light produced by highly relativistic charged particles. For the neutrino-electron elastic scattering process, we detect the recoil electron and require it to be scattered along the direction of the incident neutrino.
Contribution of σ meson exchange to elastic lepton-proton scattering
Koshchii, Oleksandr; Afanasev, Andrei
2016-12-01
Lepton mass effects play a decisive role in the description of elastic lepton-proton scattering when the beam's energy is comparable to the mass of the lepton. The future Muon Scattering Experiment (MUSE) experiment, which is devised to solve the "Proton Radius Puzzle," is going to cover the corresponding kinematic region for a scattering of muons by a proton target. We anticipate that helicity-flip meson exchanges will make a difference in the comparison of elastic electron-proton vs muon-proton scattering in MUSE. In this article, we estimate the σ meson exchange contribution in the t channel. This contribution, mediated by two-photon coupling of σ , is calculated to be at most ˜0.1 % for muons in the kinematics of MUSE, and it appears to be about 3 orders of magnitude larger than for electrons because of the lepton-mass difference.
Hashimoto, Hiroshi; Kim, Min-Geun; Abe, Kazuhisa; Cho, Seonho
2013-10-01
This paper presents a level set-based topology optimization method for noise barriers formed from an assembly of scatterers. The scattering obstacles are modeled by elastic bodies arranged periodically along the wall. Due to the periodicity, the problem can be reduced to that in a unit cell. The interaction between the elastic scatterers and the acoustic field is described in the context of the level set analysis. The semi-infinite acoustic wave regions located on the both sides of the barrier are represented by impedance matrices. The objective function is defined by the energy transmission passing the barrier. The design sensitivity is evaluated analytically by the aid of adjoint equations. The dependency of the optimal profile on the stiffness of scatterers and on the target frequency band is examined. The feasibility of the developed optimization method is proved through numerical examples.
Mechanism of elastic and inelastic proton scattering on a {sup 15}C nucleus in diffraction theory
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
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.
Application of Multiple Scattering Theory to Lower Energy Elastic Nucleon-Nucleus Reactions
Chinn, C. R.; Elster, Ch.; Thaler, R. M.; Weppner, S. P.
1994-01-01
The optical model potentials for nucleon-nucleus elastic scattering at $65$~MeV are calculated for $^{12}$C, $^{16}$O, $^{28}$Si, $^{40}$Ca, $^{56}$Fe, $^{90}$Zr and $^{208}$Pb in first order multiple scattering theory, following the prescription of the spectator expansion, where the only inputs are the free NN potentials, the nuclear densities and the nuclear mean field as derived from microscopic nuclear structure calculations. These potentials are used to predict differential cross section...
Chinn, C. R.; Elster, Ch.; Thaler, R. M.; Weppner, S. P.
1995-01-01
The theory of the elastic scattering of a nucleon from a nucleus is presented in the form of a Spectator Expansion of the optical potential. Particular attention is paid to the treatment of the free projectile$\\,-\\,$nucleus propagator when the coupling of the struck target nucleon to the residual target must be taken into consideration. First order calculations within this framework are shown for neutron total cross-sections and for proton scattering for a number of target nuclides at a varie...
Ultrasonic Scattering by an Elastic Sphere in Matrix with Imperfect Interface
WU Rui-Xin; WANG Yao-Jun
2004-01-01
The general solution of ultrasonic wave scattering by an elastic sphere embedded in solid matrix with an interface layer is developed. A transfer matrix connecting the displacement and stress components on the opposite surfaces of the layer is derived. Asymptotically expanding the transfer matrix gives the equivalent boundary conditions at an interface. A spring model for describing physically a spherical imperfect interface is thus established and its validity is evaluated. Ultrasonic scatterings respectively from rigid and slip interface are numerically compared.
Elastic scattering of a Bose-Einstein condensate at a potential landscape
2013-01-01
We investigate the elastic scattering of Bose-Einstein condensates at shallow periodic and disorder potentials. We show that the collective scattering of the macroscopic quantum object couples to internal degrees of freedom of the Bose-Einstein condensate such that the Bose-Einstein condensate gets depleted. As a precursor for the excitation of the Bose-Einstein condensate we observe wave chaos within a mean-field theory.
Large-angle. pi. /sup +/p elastic scattering at 66. 8 MeV
Brack, J.T.; Kraushaar, J.J.; Rilett, D.J.; Ristinen, R.A.; Ottewell, D.F.; Smith, G.R.; Jeppesen, R.G.; Stevenson, N.R.
1988-11-01
Pion-proton elastic scattering measurements at six angles from 101/sup 0/ to 147/sup 0/ center of mass at 66.8 MeV verify previously published differential cross sections which are at variance with earlier data of others and with generally accepted phase-shift solutions which incorporate these earlier data. The present single-arm measurements were made with solid targets and an array of scintillation counters which measured the time of flight of scattered pions.
Strong coupling effects in near-barrier heavy-ion elastic scattering
Keeley, N; Rusek, K
2014-01-01
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 18O + 184W and 16O + 148,152Sm 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 11Li scattering, where coupling to the 9Li + n + n continuum leads to an elastic scattering shape that cannot be reproduced by any standard optical model parameter set. The recent availability of high quality 6He, 11Li and 11Be 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 ab...
Extraction of structure functions for lepton-nucleus scattering in the quasi-elastic region
Kim, K. S.; Kim, Hungchong; Cheoun, Myung-Ki; So, W. Y.
2016-12-01
Within the framework of a relativistic single-particle model, we calculate inclusive electron-nucleus scattering by electromagnetic current, and neutrino-nucleus scattering by neutral and charged current in the quasi-elastic region. The longitudinal, the transverse, and the transverse-interference structure functions are extracted from the theoretical cross section by using the Rosenbluth separation method at fixed momentum transfer and scattering angle and then compared with each other from the viewpoint of these current interactions. The position of peak for the electron scattering shifts to higher energy transfer than that for the neutrino scattering. The axial and pseudoscalar terms turn out to play an important role in the neutrino-nucleus scattering.
Elastic and Inelastic Scattering of Positrons by Potassium Atoms
El-Bakry, Salah Yaseen
The investigations of the elastic and inelastic collisions of positrons with potassium atoms, K (1s2, 2s2, 2p6, 3s2, 3p6, 4s), are presented. The potassium target atoms are described using Clementi-Roetti wavefunctions within the framework of the one-valence-electron model. The total cross-sections which correspond to eight partial cross-sections are calculated at 34 values of the incident energy k21 (2.5 eV <= k12<= 100 eV) using the coupled-static approximation. The resulting total elastic, ground- and excited-positronium formation cross-sections are compared with experimental results and those calculated by other authors. In the vicinity of 6 eV, and consistent with the measurements of Parikh et al.,2 our total cross-section displays a pronounced peak. We support the conclusion of McAlinden et al.15 and Hewitt et al.14 that above about 4 eV, positronium formation is mainly into excited states. Good agreement is obtained with the total cross-section measurements of Kwan et al.1 and Parikh et al.2 Positronium formation is not important above about 50 eV.
Quasi-elastic neutron scattering studies of protein dynamics
Rorschach, H.E.
1991-03-20
The techniques of X-ray and neutron scattering that have been so successfully applied to the study of the structure of biological macromolecules have in recent years been also used for the study of the thermal motion of these molecules. The diffraction of X-rays has been widely used to investigate the high-frequency motion of the heavy-atom residues of proteins. In these studies, the mean-square thermal amplitudes can be determined from the intensities of the sharp structural lines obtained from single crystals of the hydrated proteins. Similar information can be obtained on lighter atoms from the study of the neutron scattering from single crystals. The results of these measurements are coupled closely to the rapidly developing field of theoretical molecular dynamics which is now being applied to study the dynamics of large biological molecules. This report discusses research in this area.
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
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 gas-je
Cross section in deuteron-proton elastic scattering at 1.25 GeV/u
Kurilkin, P K; Balanda, A; Belver, D; Belyaev, A; Blanco, A; Böhmer, M; Boyard, J L; Cabanelas, P; Castro, E; Chernenko, S; Díaz, J; Dybczak, A; Epple, E; Fabbietti, L; Fateev, O; Finocchiaro, P; Fonte, P; Friese, J; Fröhlich, I; Galatyuk, T; Garzón, J A; Gil, A; Golubeva, M; González-Díaz, D; Guber, F; Hennino, T; Holzmann, R; Huck, P; Ierusalimov, A; Iori, I; Ivashkin, A; Jurkovic, M; Kämpfer, B; Karavicheva, T; Koenig, I; Koenig, W; Kolb, B W; Kopp, A; Korcyl, G; Kornakov, G K; Kotte, R; Kozuch, A; Krása, A; Krizek, F; Krücken, R; Kuc, H; Kühn, W; Kugler, A; Kurepin, A; Kurilkin, A; Khlitz, P; Ladygin, V; Lamas-Valverde, J; Lang, S; Lapidus, K; Liu, T; Lopes, L; Lorenz, M; Maier, L; Mangiarotti, A; Markert, J; Metag, V; Michalska, B; Michel, J; Müntz, C; Naumann, L; Pachmayer, Y C; Palka, M; Parpottas, Y; Pechenov, V; Pechenova, O; Pietraszko, J; Przygoda, W; Ramstein, B; Reshetin, A; Roskoss, J; Rustamov, A; Sadovsky, A; Salabura, P; Schmah, A; Siebenson, J; Sobolev, Yu G; Spataro, S; Ströbele, H; Stroth, J; Sturm, C; Sudol, M; Tarantola, A; Teilab, K; Tlusty, P; Traxler, M; Trebacz, R; Tsertos, H; Vasiliev, T; Wagner, V; Weber, M; Wüstenfeld, J; Yurevich, S; Zanevsky, Y
2011-01-01
First results of the differential cross section in dp elastic scattering at 1.25 GeV/u measured with the HADES over a large angular range are reported. The obtained data corresponds to large transverse momenta, where a high sensitivity to the two-nucleon and three-nucleon short-range correlations is expected.
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.
The neutron-deuteron elastic scattering angular distribution at 95 MeV
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
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.
Measurements of the analyzing power of elastic pd-scattering at 190 MeV
Seip, M; Bieber, R; Drentje, AG; van Goethem, MJ; Harakeh, MN; Hoefman, M; Huisman, H; Kalantar-Nayestanaki, N; Kremers, HR; Messchendorp, JG; Volkerts, M; van der Werf, SY; Wilschut, HW; Desplanques, B; Protasov, K; SilvestreBrac, B; Carbonell, J
1999-01-01
A beam-polarimeter for medium energy protons and deuterons (E=100-200 MeV) has been constructed. Its operation is based on the p + d, p + p and d + p elastic scattering with coincident detection of both particles in 4 independent planes. The 16 detectors of the polarimeter have a phoswich constructi
Modeling proton and alpha elastic scattering in liquid water in Geant4-DNA
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.
Elastic scattering and fusion cross-sections in 7Li + 27Al reaction
D Patel; S Santra; S Mukherjee; B K Nayak; P K Rath; V V Parkar; R K Choudhury
2013-10-01
With an aim to understand the effects of breakup and transfer channels on elastic scattering 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 (lab = 8.0–16.0 MeV) around the Coulomb barrier. Optical model (OM) analysis of the elastic scattering data does not show any threshold anomaly or breakup threshold anomaly behaviour in the energy dependence of the real and imaginary parts of the OM potential. Fusion cross-section at each bombarding energy is extracted from the measured -particle evaporation energy spectra at backward angles by comparing with the statistical model prediction. Results on fusion cross-sections from the present measurements along with data from the literature have been compared with the coupled-channels predictions. Detailed coupled-channels calculations have been carried out to study the effect of coupling of breakup, inelastic and transfer, channels on elastic scattering and fusion. The effect of 1-stripping transfer coupling was found to be significant compared to that of the projectile breakup couplings in the present system.
Causality principle and nuclear dispersion anomaly in the elastic scattering for α+12C system
Abdolmajid Izadpanah
2010-01-01
The optical model analysis of the alpha particle elastic scattering on a carbon target was performed on the basis of the dispersion relation between the real and imaginary parts of the calculated volume integrals. A nuclear dispersion anomaly in an α+12C system was observed and interpreted clearly.
Gashi, A; Oades, G C; Rasche, G; Woolcock, W S
2001-01-01
We calculate the s and p-wave electromagnetic corrections which must be subtracted from the nuclear phase shifts obtained from the analysis of low energy pi+p elastic scattering data, in order to obtain hadronic phase shifts. We compare our results with earlier calculations and estimate the uncertainties in the corrections.
How to distinguish elastically scattered light from Stokes shifted light for solid-state lighting?
Meretska, M. L.; Lagendijk, A.; Thyrrestrup, H.; Mosk, A. P.; IJzerman, W. L.; Vos, W.L.
2016-01-01
We have studied the transport of light through phosphor diff user plates that are used in commercial solid-state lighting modules (Fortimo). These polymer plates contain YAG:Ce+3 phosphor particles that both elastically scatter and Stokes shift light in the visible wavelength range (400-700 nm). We
Van der Waals Type Model for Neutron-Proton Elastic Scattering at High Energies
Aleem, F.
1980-12-01
The most recent measurements of the angular distribution and total cross-section for neutron-proton elastic scattering between 70< pL <400 GeV/c with squared four momentum transfer -t ≤ 3.6 (GeV/c)2 have been explained using Van der Waals type model.
Simple Regge pole model for proton-proton elastic scattering at high energies
Saleem, M.; Fazal-e-Aleem
1979-06-01
It is shown that by a phenomemological choice of residue functions, the angular distribution in pp elastic scattering at high energies, including the most recent measurement at ..sqrt..s = 27.4 GeV with squared 4-momentum transfer, -t, extending up to 14 (GeV/c)/sup 2/, can be explained with simple Regge pole model.
Meson-proton elastic scattering At 250 GeV/c
Saleem, Mohammad; Rashid, Haris; Aleem, Fazal-e.
1988-01-01
Very recent measurements of pi-+p and K+p elastic scattering at 250GeV/c have been explained by using the generalised Chou-Yang model. Dips are predicted to occur at -t=3.63 and 4.36(GeV/c)2 respectively.
Antiproton-proton elastic scattering at 1. 8 TeV
Fazal-e-Aleem; Saleem, M. (Punjab Univ., Lahore (Pakistan). Centre for High Energy Physics); Yodh, G.B. (California Univ., Irvine, CA (USA). Dept. of Physics)
1990-11-01
The predictions, based on the generalized Chou-Yang model, are made for the most recent measurements of antiproton-proton elastic scattering at {radical}s = 1.8 TeV. These results have been compared with the recent theoretical predictions of various models. (author).
Quasi-elastic neutron scattering study of the mobility of methane in microporous silica
Benes, Nieck E.; Jobic, Herve; Verweij, Henk
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 occupanc
Measurement of Muon Neutrino Quasi-Elastic Scattering on Carbon
Aguilar-Arevalo, A A; Brice, S J; Brown, B C; Bugel, L; Cao, J; Coney, L; Conrad, J M; Cox, D C; Curioni, A; Djurcic, Z; Finley, D A; Fleming, B T; Ford, R; García, F G; Garvey, G T; Green, C; Green, J A; Hart, T L; Hawker, E; Imlay, R; Johnson, R A; Kasper, P; Katori, T; Kobilarcik, T; Kourbanis, I; Koutsoliotas, S; Laird, E M; Link, J M; Liu, Y; Liu, Y; Louis, W C; Mahn, K B M; Marsh, W; Martin, P S; McGregor, G; Metcalf, W; Meyers, P D; Mills, F; Mills, G B; Monroe, J; Moore, C D; Nelson, R H; Nienaber, P; Ouedraogo, S; Patterson, R B; Perevalov, D; Polly, C C; Prebys, E; Raaf, Jennifer L; Ray, H; Roe, B P; Russell, A D; Sandberg, V; Schirato, R; Schmitz, D; Shaevitz, M H; Shoemaker, F C; Smith, D; Sorel, M; Spentzouris, P; Stancu, I; Stefanski, R J; Sung, M; Tanaka, H A; Tayloe, R; Tzanov, M; Vande Water, R; Wascko, M O; White, D H; Wilking, M J; Yang, H J; Zeller, G P; Zimmerman, E D
2007-01-01
Low energy (200
Medium effect in high density region probed by nucleus-nucleus elastic scattering
Furumoto, T; Yamamoto, Y
2014-01-01
We investigate the sensitivity of the medium effect in the high density region on the nucleus-nucleus elastic scattering in the framework of the double-folding (DF) model with the complex $G$-matrix interaction. First, the evaluating position of the local density, which is an ambiguity of the DF model, is investigated. However, the effect has a minor role to the nucleus-nucleus system. Next, the medium effect including three-body-force (TBF) effect is investigated with two methods. In the both methods, the medium effect is clearly seen on the potential and the elastic cross section, but not on the total reaction cross section. Finally, we make clear the crucial role of the TBF effect up to $k_F =$ 1.6 fm$^{-1}$ in the nucleus-nucleus elastic scattering.
Multiple scattering of elastic waves: a numerical method for computing the effective wavenumbers
Chekroun, Mathieu; Lombard, Bruno; Piraux, Joël
2012-01-01
Elastic wave propagation is studied in a heterogeneous 2-D medium consisting of an elastic matrix containing randomly distributed circular elastic inclusions. The aim of this study is to determine the effective wavenumbers when the incident wavelength is similar to the radius of the inclusions. A purely numerical methodology is presented, with which the limitations usually associated with low scatterer concentrations can be avoided. The elastodynamic equations are integrated by a fourth-order time-domain numerical scheme. An immersed interface method is used to accurately discretize the interfaces on a Cartesian grid. The effective field is extracted from the simulated data, and signal-processing tools are used to obtain the complex effective wavenumbers. The numerical reference solution thus-obtained can be used to check the validity of multiple scattering analytical models. The method is applied to the case of concrete. A parametric study is performed on longitudinal and transverse incident plane waves at v...
Off-shell and nonlocal effects in proton-nucleus elastic scattering
Picklesimer, A.; Tandy, P.C.; Thaler, R.M.; Wolfe, D.H.
1984-04-01
The influence of off-shell and nonlocal effects in the first-order nonrelativistic microscopic optical potential is investigated for elastic proton scattering above 100 MeV. With the free nucleon-nucleon t matrix taken from the model of Love and Franey, these effects are significant only for scattering angles greater than about 60/sup 0/ and energies below about 300 MeV. The inadequacy of the standard first-order theory for predictions of spin observables at forward scattering angles remains unchanged when these effects are included and the need for higher order processes including medium and relativistic effects is reinforced.
Off-shell and nonlocal effects in proton-nucleus elastic scattering
Picklesimer, A.; Tandy, P. C.; Thaler, R. M.; Wolfe, D. H.
1984-04-01
The influence of off-shell and nonlocal effects in the first-order nonrelativistic microscopic optical potential is investigated for elastic proton scattering above 100 MeV. With the free nucleon-nucleon t matrix taken from the model of Love and Franey, these effects are significant only for scattering angles greater than about 60° and energies below about 300 MeV. The inadequacy of the standard first-order theory for predictions of spin observables at forward scattering angles remains unchanged when these effects are included and the need for higher order processes including medium and relativistic effects is reinforced.
11. international conference on elastic and diffractive scattering: towards high energy frontiers
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.
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.
On the Large-t Elastic Scattering at √{s} = 7 TeV
Troshin, S. M.; Tyurin, N. E.
2012-06-01
We discuss discrimination of the scattering mechanisms on the basis of functional dependencies of the large-t elastic scattering suggested by the recent data from the TOTEM experiment. It is shown that Orear exponent is in a better agreement with the data than the power-like dependence used by the TOTEM. This implies that the collective dynamics is dominating over the point-like mechanism related to the scattering of the proton constituents. We also emphasize that vanishing of the helicity-flip amplitudes contributions at the LHC energies would result in appearance of the dip-bump structures at higher values of transferred momenta.
Momentum space approach to microscopic effects in elastic proton scattering
Picklesimer, A.; Tandy, P. C.; Thaler, R. M.; Wolfe, D. H.
1984-12-01
The microscopic nonrelativistic first-order optical potential for proton-nucleus scattering is studied in some detail. Momentum-space calculations have been performed for a number of different target nuclei at proton energies above ~100 MeV and these microscopic predictions are compared with experimental cross section, analyzing power, and spin-rotation function data. The input to these calculations consists of the free on-shell nucleon-nucleon t matrix, its nonlocal and off-shell structure, the treatment of the full-folding integral, and target densities obtained from electron scattering. Off-shell and nonlocal effects, as well as various factorization approximations, are studied. The sensitivity to uncertainties in the off-shell extension of the t matrix, within the context of the Love-Franey model, is explicity displayed. Similarly, uncertainties due to nonlocalities and incomplete knowledge of nuclear densities are shown. Explicit calculations using the t matrix of Love and Franey indicate that these effects play significant roles only for relatively large angles (θ<~60°) and/or lower energies (~150 MeV). These studies reinforce the conclusion that the lack of agreement between such first-order predictions and the data for spin observables at small angles arises from a physical effect not included in the nonrelativistic first-order theory, rather than from any uncertainty in the calculation or in its input.
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.
Test of 600 and 750 MeV NN matrix on elastic scattering Glauber model calculations
Brissaud, I.
1980-09-01
The 600 and 750 MeV proton nucleus elastic scattering cross section and polarization calculations have been performed in the framework of the Glauber model to test the pp and pn scattering amplitudes deduced from a phase shift analysis by Bystricky, Lechanoine and Lehar. It is well known that up to now we do not possess a non-phenomenological NN scattering matrix at intermediate energies. However proton-nucleus scattering analyses are used to extract information about short range correlations1), Δ resonance2) or pion condensation presences)... etc. Most scattering calculations made at these energies have been done with phenomenological NN amplitudes having a gaussian q-dependence 10050_2005_Article_BF01438168_TeX2GIFE1.gif A(q) = {kσ }/{4π }(α + i) e^{ - β ^2 q^2 /2} and 10050_2005_Article_BF01438168_TeX2GIFE2.gif C(q) = {kσ }/{4π }iq(α + i) D_e - β ^2 q^2 /2 K and σ being respectively the projectile momentum and the total pN total cross section. The parameters α, β and D are badly known and are adjusted by fitting some specific reactions as p+4He elastic scattering4). Even when these amplitudes provide good fits to the data, our understanding of the dynamics of the scattering remains obscure.
Measurement of the two-photon exchange contribution in elastic ep scattering at VEPP-3
Gramolin, A.V. [Budker Institute of Nuclear Physics of SB RAS, Novosibirsk (Russian Federation); Arrington, J. [Argonne National Laboratory, Argonne (United States); Barkov, L.M. [Budker Institute of Nuclear Physics of SB RAS, Novosibirsk (Russian Federation); Dmitriev, V.F. [Budker Institute of Nuclear Physics of SB RAS, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation); Gauzshtein, V.V. [Nuclear Physics Institute of Tomsk Polytechnic University, Tomsk (Russian Federation); Golovin, R.A. [Budker Institute of Nuclear Physics of SB RAS, Novosibirsk (Russian Federation); Holt, R.J. [Argonne National Laboratory, Argonne (United States); Kaminsky, V.V.; Lazarenko, B.A.; Mishnev, S.I. [Budker Institute of Nuclear Physics of SB RAS, Novosibirsk (Russian Federation); Muchnoi, N.Yu. [Budker Institute of Nuclear Physics of SB RAS, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation); Neufeld, V.V.; Nikolenko, D.M.; Rachek, I.A.; Sadykov, R.Sh. [Budker Institute of Nuclear Physics of SB RAS, Novosibirsk (Russian Federation); Shestakov, Yu.V. [Budker Institute of Nuclear Physics of SB RAS, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation); Stibunov, V.N. [Nuclear Physics Institute of Tomsk Polytechnic University, Tomsk (Russian Federation); Toporkov, D.K. [Budker Institute of Nuclear Physics of SB RAS, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation); Vries, H. de [NIKHEF, Amsterdam (Netherlands); Zevakov, S.A. [Budker Institute of Nuclear Physics of SB RAS, Novosibirsk (Russian Federation); and others
2012-04-15
We report on the status of the Novosibirsk experiment on a precision measurement of the ratio R of the elastic e{sup +}p and e{sup -}p scattering cross sections. Such measurements determine the two-photon exchange effect in elastic electron-proton scattering. The experiment is conducted at the VEPP-3 storage ring using a hydrogen internal gas target. The ratio R is measured with a beam energy of 1.6 GeV (electron/positron scattering angles are {theta}=55 Division-Sign 75 Degree-Sign and {theta}=15 Division-Sign 25 Degree-Sign ) and 1 GeV ({theta}=65 Division-Sign 105 Degree-Sign ). We briefly describe the experimental method, paying special attention to the radiative corrections. Some preliminary results are presented.
Measurement of the two-photon exchange contribution in elastic $ep$ scattering at VEPP-3
Gramolin, A V; Barkov, L M; Dmitriev, V F; Gauzshtein, V V; Golovin, R A; Holt, R J; Kaminsky, V V; Lazarenko, B A; Mishnev, S I; Muchnoi, N Yu; Neufeld, V V; Nikolenko, D M; Rachek, I A; Sadykov, R Sh; Shestakov, Yu V; Stibunov, V N; Toporkov, D K; de Vries, H; Zevakov, S A; Zhilich, V N
2011-01-01
We report on the status of the Novosibirsk experiment on a precision measurement of the ratio $R$ of the elastic $e^+ p$ and $e^- p$ scattering cross sections. Such measurements determine the two-photon exchange effect in elastic electron-proton scattering. The experiment is conducted at the VEPP-3 storage ring using a hydrogen internal gas target. The ratio $R$ is measured with a beam energy of 1.6 GeV (electron/positron scattering angles are $\\theta = 55 \\div 75^{\\circ}$ and $\\theta = 15 \\div 25^{\\circ}$) and 1 GeV ($\\theta = 65 \\div 105^{\\circ}$). We briefly describe the experimental method, paying special attention to the radiative corrections. Some preliminary results are presented.
Elastic scattering of 6He from 12C at 38.3 MeV/nucleon
DONG Hong-Fei; MA Yin-Qun; MA Zhong-Yu
2009-01-01
The microscopic optical potential of nucleus-nucleus interaction is presented via a folding method with the isospin dependent complex nucleon-nuclear potential, which is first calculated in the framework of the Dirac-Bruecker-Hartree-Fock approach. The elastic scattering data of 6He at 229.8 MeV on 12C target are analyzed within the standard optical model. To take account of the breakup effect of 6He in the reaction an enhancing factor 3 on the imaginary potential is introduced. The calculated 6He+12C elastic scattering differential cross section is in good agreement with the experimental data. Comparisons with results in the double-folded model based on the M3Y nucleon-nucleon effective interaction and the few the body Glauber-model calculations are discussed. Our parameter free model should be of value in the description of nucleus-nucleus scattering, especially unstable nucleus-nucleus systems.
Low-energy positronium-hydrogen elastic scattering using the six-state close coupling approximation
Sinha, Prabal K. [Department of Physics, Bangabasi College, 19, Rajkumar Chakraborty Sarani, Calcutta 700 009 (India); Basu, Arindam; Ghosh, A.S. [Department of Theoretical Physics, Indian Association for the Cultivation of Science, Jadavpur, Calcutta 700 032 (India)
2000-07-14
Positronium-hydrogen elastic scattering is investigated using the six-state full close coupling approximation employing the basis set Ps(1s,2s,2p)+H(1s,2s,2p). S-wave singlet and triplet scattering and also the corresponding scattering length and effective range are compared with the corresponding predictions of Drachman and Houston and the Belfast group. We also report phase shifts up to l=2 and the integrated elastic cross sections. Present results indicate that the effect of target excitation as well as the effect of excitations of both the atoms are significant in the energy region considered. We also report the angle integrated Ps(1s)+H(1s){yields}Ps(2p)+H(1s) and Ps(1s)+H(1s){yields}Ps(1s)+H(2p) excitation cross sections. (author)
Cross-Section Measurements for Elastic and Inelastic Scattering of Neutrons from Noble Gases
Macmullin, Sean; Kidd, Mary; Tornow, Werner; Howell, Calvin; Brown, Michael; Henning, Reyco
2010-11-01
Neutron backgrounds are a significant concern to experiments that attempt to directly detect Weakly Interacting Massive Particle (WIMP) dark matter. Recoil nuclei produced by neutron elastic scattering can mimic WIMP signatures. There is insufficient experimental data available for the scattering cross-sections of neutrons with noble gases (Ne, Ar, Xe), which are candidate target materials for such experiments. Neutron elastic and inelastic scattering from neon of natural abundance was investigated at the Triangle Universities Nuclear Laboratory at neutron energies relevant to (α,n) and low-energy spallation neutron backgrounds in these experiments. The differential cross-section was measured using a time-of-flight technique at neutron energies of 8.0 and 5.0 MeV. Details of the experimental technique and current status of measurements will be presented.
Contribution of \\sigma-meson exchange to elastic lepton-proton scattering
Koshchii, O
2016-01-01
Lepton mass effects play a decisive role in description of elastic lepton-proton scattering when the beam's energy is comparable to the mass of the lepton. The future MUSE experiment, which is devised to solve the "Proton Radius Puzzle", is going to cover the corresponding kinematic region for a scattering of muons by a proton target. We anticipate that helicity-flip meson exchanges will make a difference in comparison of elastic electron-proton versus muon-proton scattering in MUSE. In this article, we estimate the $\\sigma$ meson exchange contribution in the $t$-channel. This contribution, mediated by two-photon coupling of $\\sigma$, is calculated to be at most $\\sim 0.1 \\%$ for muons in the kinematics of MUSE and it is about 3 orders in magnitude larger than for electrons because of the lepton-mass difference.
Elastic scattering of vortex electrons provides direct access to the Coulomb phase
Ivanov, I P; Surzhykov, A; Fritzsche, S
2016-01-01
Vortex electron beams are freely propagating electron waves carrying adjustable orbital angular momentum with respect to the propagation direction. Such beams were experimentally realized just a few years ago and are now used to probe various electromagnetic processes. So far, these experiments used the single vortex electron beams, either propagating in external fields or impacting a target. Here, we investigate the elastic scattering of two such aligned vortex electron beams and demonstrate that this process allows one to experimentally measure features which are impossible to detect in the usual plane-wave scattering. The scattering amplitude of this process is well approximated by two plane-wave scattering amplitudes with different momentum transfers, which interfere and give direct experimental access to the Coulomb phase. This phase (shift) affects the scattering of all charged particles and has thus received significant theoretical attention but was never probed experimentally. We show that a properly ...
Proton Polarizability Contribution: Muonic Hydrogen Lamb Shift and Elastic Scattering
Miller, Gerald A
2012-01-01
The uncertainty in the computed contribution to the Lamb shift in muonic hydrogen, DeltaE(subt) arising from proton polarizability effects entering in the two-photon exchange diagram at large virtual photon momenta is shown to be large enough to account for the proton radius puzzle. This is because the integral that determines DeltaE(subt) contains a logarithmic divergence. We evaluate this integral using a chosen form factor and also by using the dimensional regularization procedure which makes explicit the need for a low energy constant. The consequences of this new contribution to two photon exchange are approximately independent of the method of calculation and should be observable in a planned low energy lepton-proton scattering experiment planned to run at PSI.
Momentum space approach to microscopic effects in elastic proton scattering
Picklesimer, A.; Tandy, P.C.; Thaler, R.M.; Wolfe, D.H.
1984-06-01
The microscopic non-relativistic first-order optical potential for proton-nucleus scattering is studied in some detail. Momentum-space calculations have been performed for a number of different target nucli at proton energies above approx.100 MeV and these microscopic predictions are compared with experimental cross section, analyzing power, and spin-rotation function data. The input to these calculations consists of the free on-shell nucleon-nucleon t-matrix, its non-local and off-shell structure, the treatment of the full-folding integral, and target densities obtained from electron scattering. Off-shell and non-local effects, as well as various factorization approximations, are studied. The sensitivity to uncertainies in the off-shell extension of the t-matrix, within the context of the Love-Franey model, is explicitly displayed. Similarly, uncertainties due to non-localities and incomplete knowledge of nuclear densities are shown. Explicit calculations using the t-matrix of Love and Franey indicate that these effects play significant roles only for relatively large angles (THETA less than or equal to 60/sup 0/) and/or lower energies (approx.150 MeV). These studies reinforce the conclusion that the lack of agreement between such first-order predictions and the data for spin observable at small angles arises from a physical effect not included in the non-relativistic first-order theory, rather than from any uncertainty in the calculation or in its input. 31 references.
Elastic scattering of protons at the TOTEM experiment at the LHC
AUTHOR|(CDS)2080719; Csanád, Máté; Niewiadomski, Hubert
The TOTEM experiment at the LHC at CERN is optimized to measure elastic and diffractive scattering at the LHC and measures the total proton-proton cross-section with\tthe luminosity-independent method. The TOTEM experiment uses the special technique of movable beam pipe insertions -- called Roman Pots -- to detect very forward protons. The reconstruction of the forward proton kinematics requires the precise understanding of the LHC beam optics. A new method of LHC optics determination is reported, which exploits kinematical distributions of elastically scattered proton-proton data measured by the Roman Pots of the TOTEM experiment. The method has been successfully applied to data samples recorded since 2010. The interpretation of the proton-proton elastic differential cross-section is a challenging task. The geometrical model of proton-proton elastic scattering of Bialas and Bzdak is fitted to ISR data and to data measured by the TOTEM experiment at LHC energy of $\\sqrt{s}=7$~TeV. The Bialas-Bzdak model is g...
Revisiting Elastic Scattering of D(n, n)D reaction
Stanoiu, M.; Canton, L.; Kozier, K. S.; Nankov, N.; Plompen, A.; Rao, R.; Roubtsov, D.; Rouki, C.; Svenne, J. P.
2010-04-01
Interest has risen recently concerning the angular distribution of neutron elastic scattering on deuterium at low incident energies. The main subject is the amount of backscatter at energies below 3.2 MeV observed in differential cross-section measurements and represented in various evaluations. These various angles of approach encompass fundamental nuclear-data measurements, three-body nuclear-theory calculations, evaluated nuclear -data libraries and associated data processing, and the simulation of critical experiments involving heav y water. A new theoretical approach on the basis of three -nucleon theory was made that resulte d in new angular distributions. At the GELINA neutron time-of-flight facility a new experimental setup was developed to measure elastic scattering of neutrons on deuterium in the energy range of interest. The technique proposed is complementary to the earlier works by detecting the scattered neutron instead of the recoiling deuterium. The setup is an array of two HPGe detectors, each with a 10B neutron-gamma converter. Preliminary GELINA findings using a C6D6 target indicate less backscatter than predicted by ENDF/B -VII.0, in contrast to the nuclear-theory results. It is expected that completion of the planned work will reduce the uncertainty of the energy-angle distributions for deuterium elastic scattering and contribute to an improved deuterium evaluation in a future release of ENDF/B -VII.
Benedetto, Antonio; Kearley, Gordon J.
2016-10-01
A new type of neutron-scattering spectroscopy is presented that is designed specifically to measure dynamics in bio-systems that are difficult to obtain in any other way. The temporal information is largely model-free and is analogous to relaxation processes measured with dielectric spectroscopy, but provides additional spacial and geometric aspects of the underlying dynamics. Numerical simulations of the basic instrument design show the neutron beam can be highly focussed, giving efficiency gains that enable the use of small samples. Although we concentrate on continuous neutron sources, the extension to pulsed neutron sources is proposed, both requiring minimal data-treatment and being broadly analogous with dielectric spectroscopy, they will open the study of dynamics to new areas of biophysics.
Benedetto, Antonio; Kearley, Gordon J.
2016-01-01
A new type of neutron-scattering spectroscopy is presented that is designed specifically to measure dynamics in bio-systems that are difficult to obtain in any other way. The temporal information is largely model-free and is analogous to relaxation processes measured with dielectric spectroscopy, but provides additional spacial and geometric aspects of the underlying dynamics. Numerical simulations of the basic instrument design show the neutron beam can be highly focussed, giving efficiency gains that enable the use of small samples. Although we concentrate on continuous neutron sources, the extension to pulsed neutron sources is proposed, both requiring minimal data-treatment and being broadly analogous with dielectric spectroscopy, they will open the study of dynamics to new areas of biophysics. PMID:27703184
$O(\\alpha)$ QED Corrections to Polarized Elastic $\\mu e$ and Deep Inelastic $lN$ Scattering
Bardin, Dimitri Yuri; Christova, P C; Kalinovskaya, L V
1998-01-01
Two computer codes relevant for the description of deep inelastic scattering off polarized targets are discussed. The code ${\\mu}$ela deals with radiative corrections to elastic $\\mu e$ scattering, one method applied for muon beam polarimetry. The code HECTOR allows to calculate both the radiative corrections for unpolarized and polarized deep inelastic scattering, including higher order QED corrections.
Detection of elastic photon-photon scattering through four-wave coupling
Lundstrom, E
2005-01-01
According to the theory of quantum electrodynamics, photon-photon scattering can take place via exchange of virtual electron-positron pairs. Effectively, the interaction can be formulated in terms of non-linear corrections to Maxwell's equations, and hence may be treated by classical non-linear electrodynamics. Due to the strong electromagnetic fields needed to reach any noticeable effect, photon-photon scattering has not yet been observed experimentally, but recent improvements in laser technology have increased the possibility of direct detection. A verification of the phenomena would be of great scientific value as a confirmation of quantum electrodynamics. In this thesis the possibility of direct detection of elastic photon-photon scattering through four-wave coupling is investigated, both for current and future systems. It is shown how three colliding laser pulses satisfying certain matching conditions, can generate scattered radiation in a fourth resonant direction. The interaction is modeled, and the n...
Elastic scattering of polarized protons on deuterium at 800 MeV
Weston, G.S.
1984-07-01
A specific set of spin transfer coefficients has been measured for proton-deuteron elastic scattering at 800 MeV using an unpolarized liquid deuterium target. The experiment was done using the High Resolution Spectrometer (HRS) at the Los Alamos Meson Physics Facility (LAMPF) with a polarized proton beam. The scattered proton spin direction was determined using the Focal Plane Polarimeter (FPP) of the HRS, which employs a carbon analyzer. Some of the spin dependent parameters measured in this experiment are of considerable interest because they provide selective information about the nucleon-nucleon (NN) amplitude. Since the deuteron is the simplest bound nucleus, pd elastic scattering is particularly well suited for testing multiple scattering theories. These measurements will also be used to eventually determine the full pd collision matrix, which contains all possible information about the scattering process. In addition, the experimental setup is described for a polarized proton-polarized deuterium target spin transfer experiment also done at the HRS at 800 MeV incident proton energy. 71 references.
Propagator modifications in elastic nucleon-nucleus scattering within the spectator expansion
Chinn, C.R.; Elster, C.; Thaler, R.M.; Weppner, S.P. [Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235 (United States)]|[Center for Computationally Intensive Physics, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)]|[Institute of Nuclear and Particle Physics, and Department of Physics, Ohio University, Athens, Ohio 45701 (United States)]|[Physics Department, Case Western Reserve University, Cleveland, Ohio 44106 (United States)
1995-10-01
The theory of the elastic scattering of a nucleon from a nucleus is presented in the form of a spectator expansion of the optical potential. Particular attention is paid to the treatment of the free projectile-nucleus propagator when the coupling of the struck target nucleon to the residual target must be taken into consideration. First order calculations within this framework are shown for neutron total cross sections and for proton scattering for a number of target nuclides at a variety of energies. The calculated values of these observables are in very good agreement with measurement.
Low-energy elastic electron scattering form chloroethane, C2H5Cl
Sakaamini, A.; Navarro, C.; Cross, J.; Hargreaves, L. R.; Khakoo, M. A.; Fedus, Kamil; Winstead, C.; McKoy, V.
2015-10-01
We report theoretical as well as (normalized) experimental differential and integral cross sections for vibrationally elastic scattering of low-energy electrons from chloroethane, C2H5Cl, also known as ethyl chloride. The theoretical cross sections were computed using the Schwinger multichannel variational method in the single-channel approximation, with polarization effects included via virtual excitations. Cross section measurements were made at incident energies ranging from 1 to 30 eV and at scattering angles from {10}\\circ to {125}\\circ . We compare our data to previous results for C2H5Cl and for the related molecule chloromethane.
Low-energy elastic electron scattering from chloromethane, CH3Cl
Navarro, C.; Sakaamini, A.; Cross, J.; Hargreaves, L. R.; Khakoo, M. A.; Fedus, Kamil; Winstead, C.; McKoy, V.
2015-10-01
We report theoretical as well as (normalized) experimental differential and integral cross sections for vibrationally elastic scattering of low-energy electrons from chloromethane, CH3Cl, also known as methyl chloride. The theoretical cross sections were computed using the Schwinger multichannel variational method in the single-channel approximation, with polarization effects included via virtual excitations. Cross section measurements were made at incident energies ranging from 0.5 to 100 eV and at scattering angles from {5}\\circ to {125}\\circ . We compare our data to earlier previous results for this molecule.
Elastic Pion-Nucleon Scattering to $O(p^{3})$ in Heavy Baryon Chiral Perturbation Theory
Mojzis, M
1997-01-01
The elastic pi-N scattering amplitude in the isospin limit is calculated in the framework of heavy baryon chiral perturbation theory, up to the third order. Threshold parameters like scattering lengths, volumes, effective ranges, etc. are compared with data. All relevant low energy constants are fixed from the available pion-nucleon data. A clear improvement in the description of data is observed, when going from the first two orders in the chiral expansion to the third one. The importance of even higher orders is suggested by the result.
Elastic electron scattering from CH sub 3 I molecules oriented in the gas phase
Volkmer, M.; Meier, C.; Mihill, A.; Fink, M.; Boewering, N. (Fakultaet fuer Physik, Universitaet Bielefeld, D-4800 Bielefeld 1 (Germany))
1992-04-13
A novel experiment on elastic electron scattering from free, spatially oriented molecules has been performed. CH{sub 3}I molecules state selected by an electrostatic hexapole lens were oriented in a homogeneous electric field. The differential scattering cross sections were measured at an electron energy of 1 keV in the angular range of 4{degree}--14{degree} with the orientation switched on and off. From these data the orientation-dependent contribution to the molecular interference was determined. The results show a distinct oscillatory pattern as a function of momentum transfer as predicted by theory.
QED radiative corrections for elastic e (μ) p scattering in hadronic variables
Akhundov, A. A.; Alharbi, H. H.; Alhendi, H. A.
2004-08-01
A numerical analysis of QED radiative corrections for elastic e (μ) p scattering in hadronic variables at energies of the current experiment at JLab is performed. The explicit formulas from the review of Akhundov et al. [Fortschr. Phys.44, 373 (1996)] resulting from the integration over the phase space of leptonic variables plus photon are used to obtain the values of the cross sections and the radiative correction factor for unpolarized lepton-proton scattering. Our numerical results agree with the corresponding results arising from the formulas of Afanasev et al. [Phys. Lett. B514, 269 (2001); Phys. Rev. D64, 113009 (2001)].
Elastic scattering of low energy electrons in partially ionized dense semiclassical plasma
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.
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.
Soni, Jalpa; Purwar, Harsh; Lakhotia, Harshit; Chandel, Shubham; Banerjee, Chitram; Kumar, Uday; Ghosh, Nirmalya
2013-07-01
A novel spectroscopic Mueller matrix system has been developed and explored for both fluorescence and elastic scattering polarimetric measurements from biological tissues. The 4 × 4 Mueller matrix measurement strategy is based on sixteen spectrally resolved (λ = 400 - 800 nm) measurements performed by sequentially generating and analyzing four elliptical polarization states. Eigenvalue calibration of the system ensured high accuracy of Mueller matrix measurement over a broad wavelength range, either for forward or backscattering geometry. The system was explored for quantitative fluorescence and elastic scattering spectroscopic polarimetric studies on normal and precancerous tissue sections from human uterine cervix. The fluorescence spectroscopic Mueller matrices yielded an interesting diattenuation parameter, exhibiting differences between normal and precancerous tissues.
{sup 12}C+p resonant elastic scattering in the Maya active target
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.)
12C+p resonant elastic scattering in the Maya active target
Sambi, S.; Raabe, R.; Borge, M. J. G.; Caamano, M.; Damoy, S.; Fernández-Domínguez, B.; Flavigny, F.; Fynbo, H.; Gibelin, J.; Grinyer, G. F.; Heinz, A.; Jonson, B.; Khodery, M.; Nilsson, T.; Orlandi, R.; Pancin, J.; Perez-Loureiro, D.; Randisi, G.; Ribeiro, G.; Roger, T.; Suzuki, D.; Tengblad, O.; Thies, R.; Datta, U.
2015-03-01
In a proof-of-principle measurement, the Maya active target detector was employed for a 12C( p, p) resonant elastic scattering experiment in inverse kinematics. The excitation energy region from 0 to 3MeV above the proton breakup threshold in 13N 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 13N 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.
Compton sources for the observation of elastic photon-photon scattering events
Micieli, D.; Drebot, I.; Bacci, A.; Milotti, E.; Petrillo, V.; Conti, M. Rossetti; Rossi, A. R.; Tassi, E.; Serafini, L.
2016-09-01
We present the design of a photon-photon collider based on conventional Compton gamma sources for the observation of elastic γ γ 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.
Folding model study of the elastic $\\alpha + \\alpha$ scattering at low energies
Tan, Ngo Hai; Khoa, Dao T
2014-01-01
The folding model analysis of the elastic $\\alpha + \\alpha$ scattering at the incident energies below the reaction threshold of 34.7 MeV (in the lab system) has been done using the well-tested density dependent versions of the M3Y interaction and realistic choices for the $^4$He density. Because the absorption is negligible at the energies below the reaction threshold, we were able to probe the $\\alpha + \\alpha$ optical potential at low energies quite unambiguously and found that the $\\alpha + \\alpha$ overlap density used to construct the density dependence of the M3Y interaction is strongly distorted by the Pauli blocking. This result gives possible explanation of a long-standing inconsistency of the double-folding model in its study of the elastic $\\alpha + \\alpha$ and $\\alpha$-nucleus scattering at low energies using the same realistic density dependent M3Y interaction.
Elastic scattering of surface states on three-dimensional topological insulators
Wang Jing; Zhu Bang-Fen
2013-01-01
Topological insulators as a new type of quantum matter materials are characterized by a full insulating gap in the bulk and gapless edge/surface states protected by the time-reversal symmetry.We propose that the interference patterns caused by the elastic scattering of defects or impurities are dominated by the surface states at the extremal points on the constant energy contour.Within such a formalism,we summarize our recent theoretical investigations on the elastic scattering of topological surface states by various imperfections,including non-magnetic impurities,magnetic impurities,step edges,and various other defects,in comparison with the recent related experiments in typical topological materials such as BiSb alloys,Bi2Te3,and Bi2Se3 crystals.
Improved input for multi-reaction hadronic analyses from elastic pion-nucleon scattering
Revier, Joseph; Roenchen, Deborah; Doering, Michael; Workman`, Ronald
2017-01-01
In the search for missing baryonic resonances, many analyses include data from a variety of pion and photon induced reactions. For elastic πN scattering, however, usually the partial waves of the SAID or other groups are fitted, instead of data. We provide the partial-wave covariance matrices needed to perform correlated χ2 fits, in which the obtained χ2 equals the actual χ2 up to non-linear and normalization corrections. For any analysis relying on partial waves extracted from elastic pion scattering, this is a prerequisite to assess the significance of resonance signals and to assign any uncertainty on results. The compilation of the necessary data to improve hadronic analyses is presented in detail. Supported by the U.S. Department of Energy Grant DE-SC0014133, contract DE-AC05-06OR23177, and by the National Science Foundation (CAREER grant No. 1452055, PIF Grant No. 1415459).
Elastic α-{sup 12}C scattering at low energies in cluster effective field theory
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.)
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.
Walker, C G H; Matthew, J A D; El-Gomati, M M
2014-01-01
The sensitivity of Monte Carlo estimates of backscattering coefficients η to the accuracy of their input data is examined by studying the percentage change in η due to changes of 10% and 20% in the differential elastic scattering cross-section dσ/dΩ and corresponding changes in the stopping power S(E) in the primary energy range 200-10,000 eV. To a good approximation equivalent elastic and inelastic scattering changes produce equal and opposite shifts in η, a result consistent with predictions of transport theory. For medium to high atomic numbers an x% error in the specification of either S(E) or dσ/dΩ produces a percentage change in η significantly less than x%, while at low atomic number Δη/η increases approximately linearly with ln E so that Monte Carlo predictions are then more sensitive to parameter precision at high energy.
Telling, Mark T F; Neylon, Cameron; Kilcoyne, Susan H; Arrighi, Valeria
2008-09-04
Quasi-elastic neutron scattering (QENS) has been used to study the deviation from Debye-law harmonic behavior in lyophilized and hydrated apoferritin, a naturally occurring, multisubunit protein. Whereas analysis of the measured mean squared displacement (msd) parameter reveals a hydration-dependent inflection above 240 K, characteristic of diffusive motion, a hydration-independent inflection is observed at 100 K. The mechanism responsible for this low-temperature anharmonic response is further investigated, via analysis of the elastic incoherent neutron scattering intensity, by applying models developed to describe side-group motion in glassy polymers. Our results suggest that the deviation from harmonic behavior is due to the onset of methyl group rotations which exhibit a broad distribution of activated processes ( E a,ave = 12.2 kJ.mol (-1), sigma = 5.0 kJ x mol (-1)). Our results are likened to those reported for other proteins.
Analysis of the DENZ04 low-energy $\\pi^\\pm p$ elastic-scattering data
Matsinos, Evangelos
2012-01-01
This paper presents the results of an analysis of the DENZ04 low-energy $\\pi^\\pm p$ differential cross sections. We first analysed separately the $\\pi^+ p$ and the $\\pi^- p$ elastic-scattering measurements on the basis of standard low-energy expansions of the s- and p-wave $K$-matrix elements. After the removal of the outliers (eleven degrees of freedom in the initial database), we subjected the truncated $\\pi^\\pm p$ elastic-scattering databases into a common optimisation scheme using the ETH model; the optimisation failed to produce reasonable values for the model parameters. The phase-shift solution, extracted from the model fit to the data, is very odd. The problems we have encountered in the analysis of the DENZ04 data are due to the shape of the angular distributions of their $\\pi^+ p$ differential cross sections.
Target structure independent $^7\\vec{Li}$ elastic scattering at low momentum transfers
Momotyuk, O A; Crisp, A M; Keeley, N; Kemper, K W; Liendo, J; Maréchal, F; Mezhevych, S Y; Roeder, B T; Rusek, K; Schmidt, B G; Wiedeking, M
2006-01-01
Analyzing powers and cross sections for the elastic scattering of polarized 7Li by targets of 6Li, 7Li and 12C are shown to depend only on the properties of the projectile for momentum transfers of less than 1.0 fm-1. The result of a detailed analysis of the experimental data within the framework of the coupled channels model with ground state reorientation and transitions to the excited states of the projectile and targets included in the coupling schemes are presented. This work suggests that nuclear properties of weakly-bound nuclei can be tested by elastic scattering experiments, independent of the target used, if data are acquired for momentum transfers less than ~1.0 fm-1.
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.
Elastic and inelastic scattering of 50-MeV pions from 28Si and 30Si
Wienands, U.; Hessey, N.; Barnett, B. M.; Rozon, F. M.; Roser, H. W.; Altman, A.; Johnson, R. R.; Gill, D. R.; Smith, G. R.; Wiedner, C. A.; Manley, D. M.; Berman, B. L.; Crawford, H. J.; Grion, N.
1987-02-01
Angular distributions of the differential cross section for elastic and inelastic scattering of 50-MeV π+ and π- on 28Si and 30Si have been measured to a relative accuracy of 5-10 We fitted the cross section of elastic π+ and π- scattering from 28Si simultaneously with an optical model using a second-order potential of the Michigan State University form. Our best-fit parameters differ from those given previously. The ratio of the neutron and proton transition-matrix elements for the first Jπ=2+ state in 28Si is found from the inelastic cross section to be 1.13+/-0.09. For 30Si, the ratio is found to be 0.93+/-0.09, which differs significantly from the value derived from lifetime measurements on mirror nuclei.
Elastic $\\alpha$-$^{12}$C scattering at low energies in cluster effective field theory
Ando, Shung-Ichi
2016-01-01
The elastic $\\alpha$-$^{12}$C scattering at low energies is studied employing an effective field theory in which the $\\alpha$ and $^{12}$C states are treated as elementary like fields. We discuss scales of the theory at stellar energy region that the ${}^{12}$C($\\alpha$, $\\gamma$)$^{16}$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.
Transverse Beam Spin Asymmetries in Forward-Angle Elastic Electron-Proton Scattering
David Armstrong; Francois Arvieux; Razmik Asaturyan; Todd Averett; Stephanie Bailey; Guillaume Batigne; Douglas Beck; Elizabeth Beise; Jay Benesch; Louis Bimbot; James Birchall; Angela Biselli; Peter Bosted; Elodie Boukobza; Herbert Breuer; Roger Carlini; Robert Carr; Nicholas Chant; Yu-Chiu Chao; Swapan Chattopadhyay; Russell Clark; Silviu Covrig; Anthony Cowley; Daniel Dale; Charles Davis; Willie Falk; John Finn; Tony Forest; Gregg Franklin; Christophe Furget; David Gaskell; Joseph Grames; Keith Griffioen; Klaus Grimm; Benoit Guillon; Hayko Guler; Lars Hannelius; Richard HASTY; Alice Hawthorne Allen; Tanja Horn; Kathleen Johnston; Mark Jones; Peter Kammel; Reza Kazimi; Paul King; Ameya Kolarkar; Elie Korkmaz; Wolfgang Korsch; Serge Kox; Joachim Kuhn; Jeff Lachniet; Lawrence Lee; Jason Lenoble; Eric Liatard; Jianglai Liu; Berenice Loupias; Allison Lung; Dominique Marchand; Jeffery Martin; Kenneth McFarlane; David McKee; Robert McKeown; Fernand Merchez; Hamlet Mkrtchyan; Bryan Moffit; M. Morlet; Itaru Nakagawa; Kazutaka Nakahara; Retief Neveling; Silvia Niccolai; S. Ong; Shelley Page; Vassilios Papavassiliou; Stephen Pate; Sarah Phillips; Mark Pitt; Benard Poelker; Tracy Porcelli; Gilles Quemener; Brian Quinn; William Ramsay; Aamer Rauf; Jean-Sebastien Real; Julie Roche; Philip Roos; Gary Rutledge; Jeffery Secrest; Neven Simicevic; Gregory Smith; Damon Spayde; Samuel Stepanyan; Marcy Stutzman; Vince Sulkosky; Vincent Sulkosky; Vince Sulkosky; Vincent Sulkosky; Vardan Tadevosyan; Raphael Tieulent; Jacques Van de Wiele; Willem van Oers; Eric Voutier; William Vulcan; Glen Warren; Steven Wells; Steven Williamson; Stephen Wood; Chen Yan; Junho Yun; Valdis Zeps
2007-08-01
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 two-photon 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.
On elastic proton-proton diffraction scattering and its energy dependence
Henzi, R
1979-01-01
Recent FNAL and CERN ISR data on proton-proton elastic scattering and total cross sections at momenta q/sub L/=200-2000 GeV/c and momentum transfers up to mod t mod =14 (GeV/c)/sup 2/ are discussed in terms of a short range expansion (SRE) of the inelastic overlap function (IOF). Model independence of the conclusions is established, which are also shown to be unaffected by real part and spin effects. (25 refs).
A quasi-elastic neutron scattering and neutron spin-echo study of hydrogen bonded system
Branca, C.; Faraone, A.; Magazu, S.; Maisano, G.; Mangione, A
2004-07-15
This work reports neutron spin echo results on aqueous solutions of trehalose, a naturally occurring disaccharide of glucose, showing an extraordinary bioprotective effectiveness against dehydration and freezing. We collected data using the SPAN spectrometer (BENSC, Berlin) on trehalose aqueous solutions at different temperature values. The obtained findings are compared with quasi-elastic neutron scattering results in order to furnish new results on the dynamics of the trehalose/water system on the nano and picoseconds scale.
Mobility of hydrogen in microporous silica studied with quasi-elastic neutron scattering
Benes, Nieck E.; Jobic, Herve; Reat, Valerie; Bouwmeester, Henny J.M.; Verweij, Henk
2003-01-01
The mobility of H2 in microporous amorphous silica is studied using quasi-elastic neutron scattering. At T=90 K the self-diffusion coefficient is approximately Ds=1.2×10−8 m2 s−1 for low degrees of occupancy (<20%) and decreases slightly to Ds=0.95×10−8 m2 s−1 for an occupancy of 31%. A rough esti
Gashi, A; Oades, G C; Rasche, G; Woolcock, W S
1999-01-01
We calculate for the s-, p(1/2)- and p(3/2)-waves the electromagnetic corrections which must be subtracted from the nuclear phase shifts obtained from the analysis of low energy pi+ 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 qualitatively estimate the uncertainties in the corrections.
On higher order radiative corrections to elastic electron–proton scattering
Arbuzov, A. B., E-mail: arbuzov@theor.jinr.ru [Bogoliubov Laboratory of Theoretical Physics, JINR, 141980, Dubna (Russian Federation); Department of Higher Mathematics, Dubna State University, 141982, Dubna (Russian Federation); Kopylova, T. V. [Department of Higher Mathematics, Dubna State University, 141982, Dubna (Russian Federation)
2015-12-18
QED radiative corrections to elastic electron–proton scattering at low energies are discussed. Corrections to the electron line and effects due to vacuum polarization are computed. Higher order effects are estimated for the conditions of the experiment on the electric and magnetic proton form factors by the A1 Collaboration. Calculations are performed within the next-to-leading approximation. The inclusion of the higher order effects can affect the value of the proton charge radius extracted from the experimental data.
On higher order radiative corrections to elastic electron-proton scattering
Arbuzov, A.B. [Bogoliubov Laboratory of Theoretical Physics, Dubna (Russian Federation); Dubna State University, Department of Higher Mathematics, Dubna (Russian Federation); Kopylova, T.V. [Dubna State University, Department of Higher Mathematics, Dubna (Russian Federation)
2015-12-15
QED radiative corrections to elastic electron-proton scattering at low energies are discussed. Corrections to the electron line and effects due to vacuum polarization are computed. Higher order effects are estimated for the conditions of the experiment on the electric and magnetic proton form factors by the A1 Collaboration. Calculations are performed within the next-to-leading approximation. The inclusion of the higher order effects can affect the value of the proton charge radius extracted from the experimental data. (orig.)
Van der Waals Type Model and Structure in π-p Elastic Scattering at High Energies
Aleem, F.
1982-10-01
The most recent measurement of the angular distribution for π-p elastic scattering at pL =50 and 200 GeV/c which show a structure near -t ≈ 4(GeV/c)2, with squared four momentum transfer -t extended to 10(GeV/c)2, and the total cross section data for 50 ≤ pL ≤ 370 GeV/c have been simultaneously explained by using Van der Waal's type model.
Dipole pomeron and. pi. /sup -/p elastic scattering at high energies
Fazal-E-Aleem (Panjab Univ., Lahore (Pakistan). Physics Dept.)
1982-10-16
The differential cross-sections for high-energy ..pi../sup -/p elastic scattering showing structure near -t=4 (GeV/c)/sup 2/ for psub(L)=50 and 200 GeV/c together with total cross-sections for 50<=psub(L)<=370 GeV/c, and with -t extending up to 11 (GeV/c)/sup 2/ have been fitted by using a dipole pomeron model.
Analyzing power in n vector+d elastic scattering at 67 MeV
Ruehl, H.; Dechant, B.; Krug, J.; Luebcke, W.; Spangardt, G.; Steinke, M.; Stephan, M.; Kamke, D. (Bochum Univ. (Germany, F.R.). Inst. fuer Experimentalphysik 1); Balewski, J.; Bodek, K.; Jarczyk, L.; Strzalkowski, A. (Uniwersytet Jagiellonski, Krakow (Poland). Inst. Fizyki); Hajdas, W.; Kistryn, S.; Mueller, R.; Lang, J. (Eidgenoessische Technische Hochschule, Zurich (Switzerland). Inst. fuer Mittelenergiephysik); Henneck, R. (Basel Univ. (Switzerland). Inst. fuer Physik); Witala, H.; Cornelius, T.; Gloeckle, W. (Bochum Univ. (Germany, F.R.). Inst. fuer Theoretische Physik 2)
1991-03-18
The analyzing power A{sub y} of {sup 2}H(n vector, n){sup 2}H elastic scattering at E{sub n}=67 MeV has been measured in the angular range 30deg<{theta}{sub c.m.}<165deg. The data are in good agreement with the results of our rigorous three-nucleon calculations employing the PARIS and the BONN B potential. (orig.).
Calculation of Spin Observables for Proton-Proton Elastic Scattering in the Bethe-Salpeter Equation
Kinpara, Susumu
2015-01-01
Bethe-Salpeter equation is applied to $p$-$p$ elastic scattering. The observables of spin are calculated in the framework of the M matrix using the two-body interaction potential. The parameter of the pseudovector coupling constant is adjusted so as to reproduce the spin singlet part. It is shown that the spin rotation $R(\\theta)$ and $A(\\theta)$ are improved by the resonance effect for ${}^{\\rm 1}S_{\\rm 0}$.
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.
Polarization observables in dp backward elastic scattering at high and intermediate energies
Tanifuji, M; Iseri, Y
1998-01-01
The tensor analyzing power $T_{20}$ and the polarization transfer coefficients $\\kappa_0 (= 3/2 K_y^y)$ and $K_{xz}^y$ are investigated for dp backward elastic scattering by the invariant-amplitude method. Discrepancies between the conventional calculations and the experimental data on $T_{20}$ and imaginary parts in the amplitudes. The quantity $K_{xz}^y$ is shown to be useful in criticizing nuclear force assumptions.
Analysis of the low-energy $\\pi^\\pm p$ elastic-scattering data
Matsinos, Evangelos
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, we first investigated 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 differences to our previous PSA: a) we now perform only \\emph{one} test for the acceptance of each data set (based on its contribution to the overall $\\chi^2$) and b) we adopt a more stringent acceptance criterion in the statistical tests, by raising the minimal p-value (for the acceptance of the null hypothesis) from the equivalent of a $3 \\sigma$ effect in the normal distribution to $2.5 \\sigma$; the new value is closer to the 'common' preference for the outset of statistical significance ($1.00 \\cdot 10^{-2}$). We show that it is possible to obtain self-consistent databases after removing a very small amount of th...
Elastic scattering of 17O+208Pb at energies near the Coulomb barrier
Torresi D.
2016-01-01
Full Text Available Within the frame of the commissioning of a new experimental apparatus EXPADES we undertook the measurement of the elastic scattering angular distribution for the system 17O+208Pb at energy around the Coulomb barrier. The reaction dynamics induced by loosely bound Radioactive Ion Beams is currently being extensively studied [4]. In particular the study of the elastic scattering process allows to obtain direct information on the total reaction cross section of the exotic nuclei. In order to understand the effect of the low binding energy on the reaction mechanism it is important to compare radioactive weakly bound nuclei with stable strongly-bound nuclei. In this framework the study of the 17O+208Pb elastic scattering can be considered to be complementary to a previous measurement of the total reaction cross section for the system 17F+208Pb at energies of 86, 90.4 MeV [5, 6]. The data will be compared with those obtained for the neighboring systems 16,18O+208Pb and others available in literature.
Elastic scattering of 17O+208Pb at energies near the Coulomb barrier
Torresi, D.; Strano, E.; Mazzocco, M.; Boiano, A.; Boiano, C.; Di Meo, P.; La Commara, M.; Manea, C.; Nicoletto, M.; Grebosz, J.; Guglielmetti, A.; Molini, P.; Parascandolo, C.; Pierroutsakou, D.; Signorini, C.; Soramel, F.; Toniolo, N.; Filipescu, D.; Gheorghe, A.; Glodariu, T.; Jeong, S.; Kim, Y. H.; Lay, J. A.; Miyatake, H.; Pakou, A.; Sgouros, O.; Soukeras, V.; Stroe, L.; Vitturi, A.; Watanabe, Y.; Zerva, K.
2016-05-01
Within the frame of the commissioning of a new experimental apparatus EXPADES we undertook the measurement of the elastic scattering angular distribution for the system 17O+208Pb at energy around the Coulomb barrier. The reaction dynamics induced by loosely bound Radioactive Ion Beams is currently being extensively studied [4]. In particular the study of the elastic scattering process allows to obtain direct information on the total reaction cross section of the exotic nuclei. In order to understand the effect of the low binding energy on the reaction mechanism it is important to compare radioactive weakly bound nuclei with stable strongly-bound nuclei. In this framework the study of the 17O+208Pb elastic scattering can be considered to be complementary to a previous measurement of the total reaction cross section for the system 17F+208Pb at energies of 86, 90.4 MeV [5, 6]. The data will be compared with those obtained for the neighboring systems 16,18O+208Pb and others available in literature.
Ramazani-Moghaddam-Arani, A.; Amir-Ahmadi, H. R.; Bacher, A. D.; Bailey, C. D.; Biegun, A.; Eslami-Kalantari, M.; Gašparić, 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.
2011-05-01
This paper discusses some of the recent results obtained in a deuteron-deuteron scattering experiment using a polarized beam of deuterons with an incident energy of 130 MeV. A 4π detection system allowed to measure cross sections and spin observables for various final-state configurations. Here, we discuss the quasi-free elastic deuteron-proton scattering process in deuteron-deuteron scattering which has been observed by analyzing kinematical configurations for which the target neutron acts as a spectator particle. This part of the data can be compared directly to three-nucleon calculations and with existing data for the elastic deuteron-proton scattering process. The results for the polarization observables iT11 and T22 agree well with elastic scattering data published so-far and measured concurrently using a proton target. Surprisingly, the tensor observable T20 shows significant discrepancies with data taken using a proton target.
Microscopic description of elastic and direct inelastic nucleon scattering off spherical nuclei
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.)
Lindsley, E. H.; Farkas, D. L.
2008-02-01
We have designed and built an imaging elastic scattering spectroscopy endoscopic instrument for the purpose of detecting cancer in vivo. As part of our testing and validation of the system, known targets representing potential disease states of interest were constructed using polystyrene beads of known average diameter and TiO II crystals embedded in a two-layer agarose gel. Final construction geometry was verified using a dissection microscope. The phantoms were then imaged using the endoscopic probe at a known incident angle, and the results compared to model predictions. The mathematical model that was used combines classic ray-tracing optics with Mie scattering to predict the images that would be observed by the probe at a given physical distance from a Mie-regime scattering media. This model was used generate the expected observed response for a broad range of parameter values, and these results were then used as a library to fit the observed data from the phantoms. Compared against the theoretical library, the best matching signal correlated well with known phantom material dimensions. These results lead us to believe that imaging elastic scattering can be useful in detection/diagnosis, but further refinement of the device will be necessary to detect the weak signals in a real clinical setting.
Phase-shift analysis of low-energy $\\pi^{\\pm}p$ elastic-scattering data
Matsinos, E; Oades, G C; Rasche, G; Woolcock, W S
2006-01-01
Using electromagnetic corrections previously calculated by means of a potential model, we have made a phase-shift analysis of the $\\pi^\\pm p$ 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 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 $\\pi N N$ coupling constant (in the standard form) is $0.0733 \\pm 0.0014$. 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 t...
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.
Araki, Samuel J.
2016-11-01
In the plumes of Hall thrusters and ion thrusters, high energy ions experience elastic collisions with slow neutral atoms. These collisions involve a process of momentum exchange, altering the initial velocity vectors of the collision pair. In addition to the momentum exchange process, ions and atoms can exchange electrons, resulting in slow charge-exchange ions and fast atoms. In these simulations, it is particularly important to accurately perform computations of ion-atom elastic collisions in determining the plume current profile and assessing the integration of spacecraft components. The existing models are currently capable of accurate calculation but are not fast enough such that the calculation can be a bottleneck of plume simulations. This study investigates methods to accelerate an ion-atom elastic collision calculation that includes both momentum- and charge-exchange processes. The scattering angles are pre-computed through a classical approach with ab initio spin-orbit free potential and are stored in a two-dimensional array as functions of impact parameter and energy. When performing a collision calculation for an ion-atom pair, the scattering angle is computed by a table lookup and multiple linear interpolations, given the relative energy and randomly determined impact parameter. In order to further accelerate the calculations, the number of collision calculations is reduced by properly defining two cut-off cross-sections for the elastic scattering. In the MCC method, the target atom needs to be sampled; however, it is confirmed that initial target atom velocity does not play a significant role in typical electric propulsion plume simulations such that the sampling process is unnecessary. With these implementations, the computational run-time to perform a collision calculation is reduced significantly compared to previous methods, while retaining the accuracy of the high fidelity models.
Faurie, D [LPMTM, UPR 9001 CNRS, Universite Paris-Nord, 93430 Villetaneuse (France); Djemia, P [LPMTM, UPR 9001 CNRS, Universite Paris-Nord, 93430 Villetaneuse (France); Renault, P-O [LMP, UMR 6630 CNRS, Universite de Poitiers, 86962 Futuroscope (France); Roussigne, Y [LPMTM, UPR 9001 CNRS, Universite Paris-Nord, 93430 Villetaneuse (France); Cherif, S M [LPMTM, UPR 9001 CNRS, Universite Paris-Nord, 93430 Villetaneuse (France); Bourhis, E Le [LMP, UMR 6630 CNRS, Universite de Poitiers, 86962 Futuroscope (France); Goudeau, Ph [LMP, UMR 6630 CNRS, Universite de Poitiers, 86962 Futuroscope (France)
2007-12-15
We have shown a strong texture effect on elastic properties of gold thin films deposited by physical vapour deposition. Elastic properties of non-textured and {l_brace}111{r_brace} fiber textured gold thin films were investigated by x-ray diffraction combined with in-situ tensile testing and Brillouin light scattering. These static and dynamic methods allowed characterizing the local and macroscopic elastic behavior of gold films.
Tomalak, O. [Johannes Gutenberg Universitaet, Institut fuer Kernphysik, Mainz (Germany); Johannes Gutenberg-Universitaet, PRISMA Cluster of Excellence, Mainz (Germany); Taras Shevchenko National University of Kyiv, Department of Physics, Kyiv (Ukraine); Vanderhaeghen, M. [Johannes Gutenberg Universitaet, Institut fuer Kernphysik, Mainz (Germany); Johannes Gutenberg-Universitaet, PRISMA Cluster of Excellence, Mainz (Germany)
2015-02-01
We apply a subtracted dispersion relation formalism with the aim to improve predictions for the two-photon exchange corrections to elastic electron-proton scattering observables at finite momentum transfers. We study the formalism on the elastic contribution, and make a detailed comparison with existing data for unpolarized cross sections as well as polarization transfer observables. (orig.)
Electron elastic scattering off $A$@C$_{60}$: The role of atomic polarization under confinement
Dolmatov, V K; Chernysheva, L V
2015-01-01
The present paper explores possible features of electron elastic scattering off endohedral fullerenes $A$@C$_{60}$. It focuses on how dynamical polarization of the encapsulated atom $A$ by an incident electron might alter scattering off $A$@C$_{60}$ compared to the static-atom-$A$ case, as well as how the C$_{60}$ confinement modifies the impact of atomic polarization on electron scattering compared to the free-atom case. The aim is to provide researchers with a "relative frame of reference" for understanding which part of the scattering processes could be due to electron scattering off the encapsulated atom and which due to scattering off the C$_{60}$ cage. To meet the goal, the C$_{60}$ cage is modeled by an attractive spherical potential of a certain inner radius, thickness, and depth which is a model used frequently in a great variety of fullerene studies to date. Then, the Dyson equation for the self-energy part of the Green's function of an incident electron moving in the combined field of an encapsulat...
Elastic scattering of polarized protons on helium three at 800 MeV
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.
Elastic neutron scattering studies at 96 MeV for transmutation.
Osterlund, M; Blomgren, J; Hayashi, M; Mermod, P; Nilsson, L; Pomp, S; Ohrn, A; Prokofiev, A V; Tippawan, U
2007-01-01
Elastic neutron scattering from (12)C, (14)N, (16)O, (28)Si, (40)Ca, (56)Fe, (89)Y and (208)Pb has been studied at 96 MeV in the10-70 degrees interval, using the SCANDAL (SCAttered Nucleon Detection AssembLy) facility. The results for (12)C and (208)Pb have recently been published, while the data on the other nuclei are under analysis. The achieved energy resolution, 3.7 MeV, is about an order of magnitude better than for any previous experiment above 65 MeV incident energy. A novel method for normalisation of the absolute scale of the cross section has been used. The estimated normalisation uncertainty, 3%, is unprecedented for a neutron-induced differential cross section measurement on a nuclear target. Elastic neutron scattering is of utmost importance for a vast number of applications. Besides its fundamental importance as a laboratory for tests of isospin dependence in the nucleon-nucleon, and nucleon-nucleus, interaction, knowledge of the optical potentials derived from elastic scattering come into play in virtually every application where a detailed understanding of nuclear processes is important. Applications for these measurements are dose effects due to fast neutrons, including fast neutron therapy, as well as nuclear waste incineration and single event upsets in electronics. The results at light nuclei of medical relevance ((12)C, (14)N and (16)O) are presented separately. In the present contribution, results on the heavier nuclei are presented, among which several are of relevance to shielding of fast neutrons.
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 ...
How to distinguish elastically scattered light from Stokes shifted light for solid-state lighting?
Meretska, M; Thyrrestrup, H; Mosk, A P; IJzerman, W L; Vos, W L
2015-01-01
We have studied the transport of light through phosphor diffuser plates that are used in commercial solid-state lighting modules (Fortimo). These polymer plates contain $\\mathrm{YAG:Ce}^{+3}$ phosphor particles that elastically scatter light and Stokes shifts it in the visible wavelength range (400-700 nm). We excite the phosphor with a narrowband light source, and measure spectra of the outgoing light. The Stokes shifted light is separated from the elastically scattered light in the measured spectra and using this technique we isolate the elastic transmission of the plates. This result allows us to extract the transport mean free path $l_{\\mathrm{tr}}$ over the full wavelength range by employing diffusion theory. Simultaneously, we determine the absorption mean free path $l_{\\mathrm{abs}}$ in the wavelength range 400 to 530 nm where $\\mathrm{YAG:Ce}^{+3}$ absorbs. The diffuse absorption $\\mu_{\\mathrm{a}} =\\frac{1}{l_{\\mathrm{abs}}}$ spectrum is qualitative similar to the absorption coefficient of $\\mathrm{YA...
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.
Rorschach, H.E.
1993-05-25
Results that shed new light on the study of protein dynamics were obtained by quasi-elastic neutron scattering. The triple axis instrument H-9 supplied by the cold source was used to perform a detailed study of the quasi-elastic spectrum and the Debye-Waller factor for trypsin in powder form, in solution, and in crystals. A preliminary study of myoglobin crystals was also done. A new way to view the results of quasi-elastic scattering experiments is sketched, and the data on trypsin are presented and analyze according to this new picture.
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.
Proton form factors and two-photon exchange in elastic electron-proton scattering
Nikolenko, D. M., E-mail: D.M.Nikolenko@inp.nsk.su [Russian Academy of Sciences, Budker Institute of Nuclear Physics, Siberian Branch (Russian Federation); Arrington, J. [Argonne National Laboratory (United States); Barkov, L. M. [Russian Academy of Sciences, Budker Institute of Nuclear Physics, Siberian Branch (Russian Federation); Vries, H. de [NIKHEF (Netherlands); Gauzshtein, V. V. [National Research Tomsk Polytechnic University, Physical-Technical Institute (Russian Federation); Golovin, R. A.; Gramolin, A. V.; Dmitriev, V. F.; Zhilich, V. N.; Zevakov, S. A.; Kaminsky, V. V.; Lazarenko, B. A.; Mishnev, S. I.; Muchnoi, N. Yu.; Neufeld, V. V.; Rachek, I. A.; Sadykov, R. Sh. [Russian Academy of Sciences, Budker Institute of Nuclear Physics, Siberian Branch (Russian Federation); Stibunov, V. N. [National Research Tomsk Polytechnic University, Physical-Technical Institute (Russian Federation); Toporkov, D. K. [Russian Academy of Sciences, Budker Institute of Nuclear Physics, Siberian Branch (Russian Federation); Holt, R. J. [Argonne National Laboratory (United States); and others
2015-05-15
Proton electromagnetic form factors are among the most important sources of information about the internal structure of the proton. Two different methods for measuring these form factors, the method proposed by Rosenbluth and the polarization-transfer method, yield contradictory results. It is assumed that this contradiction can be removed upon taking into account the hard part of the contribution of two-photon exchange to the cross section for elastic electron-proton scattering. This contribution can measured experimentally via a precision comparison of the cross sections for the elastic scattering of positrons and electrons on protons. Such a measurement, performed at the VEPP-3 storage ring in Novosibirsk at the beam energies of 1.6 and 1.0 GeV for positron (electron) scattering angles in the ranges of θ{sub e} = 15°–25° and 55°–75° in the first case and in the range of θ{sub e} = 65°–105° in the second case is described in the present article. Preliminary results of this experiment and their comparison with theoretical predictions are described.
Quasi-Elastic Neutron Scattering Studies of the Slow Dynamics of Supercooled and Glassy Aspirin
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.
Biophotonics of skin: method for correction of deep Raman spectra distorted by elastic scattering
Roig, Blandine; Koenig, Anne; Perraut, François; Piot, Olivier; Gobinet, Cyril; Manfait, Michel; Dinten, Jean-Marc
2015-03-01
Confocal Raman microspectroscopy allows in-depth molecular and conformational characterization of biological tissues non-invasively. Unfortunately, spectral distortions occur due to elastic scattering. Our objective is to correct the attenuation of in-depth Raman peaks intensity by considering this phenomenon, enabling thus quantitative diagnosis. In this purpose, we developed PDMS phantoms mimicking skin optical properties used as tools for instrument calibration and data processing method validation. An optical system based on a fibers bundle has been previously developed for in vivo skin characterization with Diffuse Reflectance Spectroscopy (DRS). Used on our phantoms, this technique allows checking their optical properties: the targeted ones were retrieved. Raman microspectroscopy was performed using a commercial confocal microscope. Depth profiles were constructed from integrated intensity of some specific PDMS Raman vibrations. Acquired on monolayer phantoms, they display a decline which is increasing with the scattering coefficient. Furthermore, when acquiring Raman spectra on multilayered phantoms, the signal attenuation through each single layer is directly dependent on its own scattering property. Therefore, determining the optical properties of any biological sample, obtained with DRS for example, is crucial to correct properly Raman depth profiles. A model, inspired from S.L. Jacques's expression for Confocal Reflectance Microscopy and modified at some points, is proposed and tested to fit the depth profiles obtained on the phantoms as function of the reduced scattering coefficient. Consequently, once the optical properties of a biological sample are known, the intensity of deep Raman spectra distorted by elastic scattering can be corrected with our reliable model, permitting thus to consider quantitative studies for purposes of characterization or diagnosis.
Large angle elastic and inelastic scattering of 14.93 keV photons
Singh, P.; Mehta, D.; Kumar, S.; Sharma, M.; Puri, S.; Shahi, J.S.; Singh, N. E-mail: nsingh@pu.ac.in
2004-07-01
Elastic and inelastic scattering cross-sections for the 14.93 keV photons (Y-K{alpha} X-rays) were measured at an angle of 141 deg. in the elements with 6 {<=} Z {<=} 92 and 1 {<=} Z {<=} 50, respectively. A reflection mode geometrical arrangement involving a Y-foil excited by the 59.54 keV {gamma}-rays from the {sup 241}Am radioisotope as photon source and an HPGe/Si(Li) detector was used. The measurements were performed under vacuum {approx}10{sup -2} Torr. Special care was taken in determination of the incident photon intensity and geometrical factors and to check effects due to occurrence of Bragg diffraction from the target lattice. The measured elastic scattering cross-sections have been compared with predictions from the form-factor formalism and relativistic second-order S-matrix calculations. The modified form-factor (MF) cross-sections are higher up to 50% than the measured ones in the case of elements with the electron binding energy (BE) in vicinity of the incident photon energy and are lower up to 20% for the other elements. These deviations are smoothed by incorporating the Anomalous Scattering Factors (ASFs) to the MF values [Acta Cryst. A 46 (1990) 170]. The S-matrix values exhibit general agreement with the measured cross-sections. The measured inelastic scattering cross-sections are found to be in good agreement with those calculated using the Klein-Nishina cross-section incorporating the Hartree-Fock incoherent scattering function (ISF)
Geometry Survey of the Time-of-Flight Neutron-Elastic Scattering (Antonella) Experiment
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.
Saleem, M.; Fazal-E-Aleem; Azhar, I.A.
1988-06-01
The various characteristics of pp and antipp elastic scattering at high energies are explained by using the generalized Chou-Yang model which takes into consideration the anisotropic scattering of objects constituting colliding particles. The model is also used to extract the form factor and radius of the ..lambda.. particle.
Search for narrow baryons in pi /sup -/p elastic scattering at large angles
Baillon, Paul; Benayoun, M; Chauveau, J; Chew, D; Ferro-Luzzi, M; Kahane, J; Lellouch, D; Leruste, P; Liaud, P; Moreau, F; Perreau, J M; Séguinot, Jacques; Sené, R; Tocqueville, J; Urban, M
1980-01-01
Hoping to find resonant structures in the momentum dependence of pi /sup -/p elastic scattering the authors have measured the differential cross section for this reaction at c.m. angles near 90 degrees . An intense pion beam ( approximately=10/sup 7/ pi /s) has been used, together with a high incident momentum resolution (dP/P approximately =2*10/sup -4/), to scan the region of laboratory momenta from 5.75 to 13.02 GeV/c (c.m. energy from 3.42 to 5.03 GeV). The sensitivity attained by the experiment is such that signals would have been seen corresponding to the formation of non-strange baryon resonances having width larger than approximately=0.1 MeV and elasticity larger than a few per cent. Within these limits no resonances were sighted. (4 refs) .
Quasi-elastic electron-deuteron scattering and the electric form factor of the neutron
Arenhoevel, H.; Kim, Y.E. (Mainz Univ. (Germany, F.R.). Inst. fuer Kernphysik); Craver, B.A. (Purdue Univ., Lafayette, IN (USA). Dept. of Physics); Fabian, W. (State Univ. of New York, Stony Brook (USA). Dept. of Physics); Saylor, D.P. (Worcester Polytechnic Inst., MA (USA). Dept. of Physics)
1978-09-02
The possibility of extracting accurately the neutron electric form factor from electron-neutron coincidence measurements in quasi-elastic electron-deuteron scattering is investigated for squared three-momentum transfers q/sup 2/<=30 fm/sup -2/ using the Reid soft-core, Hamada-Johnston and Bryan-Gersten potentials. It is found that contributions of the electric form factor of the neutron to the quasi-elastic cross section can be as large as 5.4% at q/sup 2/ approximately equal to 1 fm/sup -2/ (approximately 3% at q/sup 2/ approximately equal to 10 approximately 20 fm/sup 2/). Potential model dependence and corrections due to meson exchange currents and isobar configurations are found to be small (< or approximately 1%).
Water wave scattering by an elastic thin vertical plate submerged in finite depth water
Chakraborty, Rumpa; Mandal, B. N.
2013-12-01
The problem of water wave scattering by a thin vertical elastic plate submerged in uniform finite depth water is investigated here. The boundary condition on the elastic plate is derived from the Bernoulli-Euler equation of motion satisfied by the plate. Using the Green's function technique, from this boundary condition, the normal velocity of the plate is expressed in terms of the difference between the velocity potentials (unknown) across the plate. The two ends of the plate are either clamped or free. The reflection and transmission coefficients are obtained in terms of the integrals' involving combinations of the unknown velocity potential on the two sides of the plate, which satisfy three simultaneous integral equations and are solved numerically. These coefficients are computed numerically for various values of different parameters and depicted graphically against the wave number in a number of figures.
Hu, Q; Gillitzer, A; Grzonka, D; Khoukaz, A; Klehr, F; Lehrach, A; Prasuhn, D; Ritman, J; Sefzick, T; Stockmann, T; Täschner, A; Wuestner, P; Xu, H
2014-01-01
The design and construction of a recoil detector for the measurement of recoil protons of antiproton-proton elastic scattering at scattering angles close to 90$^{\\circ}$ 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.
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.
Analysis of the Quasi-Elastic Scattering of Neutrons in Hydrogenous Liquids
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.
Charge Symmetry Breaking in the Nucleon and Parity Violating Elastic Electron-Proton Scattering
Miller, Gerald A
2014-01-01
The basic facts of charge symmetry breaking (CSB) phenomena are reviewed. The relevance of CSB to parity-violating electron-proton scattering experiments that seek to extract strange elastic form factors is discussed. Experimentalists have stated and written that the current uncertainty in our knowledge of CSB limits the ability to push further on the strange form factors. I discuss recent calculations using relativistic chiral perturbation theory and realistic values of strong coupling constants which show that the uncertainties due to lack of knowledge of CSB are at least ten times smaller than present experimental uncertainties. Estimates of CSB effects are made for the JLab Qweak and Mainz P2 experiments.
Elastic differential cross sections of electron scattering by CF4 at intermediate energies
无
2000-01-01
The elastic differential cross sections(DCS)for electron scattering from CF4 are calculated at six impact energies(in 100-700 eV)employing the independent atom model(IAM)with partial waves. The atoms are presented by a model complex optical potential which is composed of static, exchange, polarization, and absorption terms. The electron density function ρ(r) is obtained by a fitting procedue to the Dirac-Hartree-Fock-Slater sef-consistent data. Compared with available experimental data, the present approach gives good results.
Nuclear Slope Parameter Of pp and (-p)p Elastic Scattering in QCD Inspired Model
MA Shan-Jun; LU Juan; LU Hai-Liang; MA Wei-Xing; FAN Hong-Yi; HE Xiao-Rong
2008-01-01
Based on the quaxk-gluon structure of nucleon and the possible existence of Odderon in strong interaction process due to gluon self-interaction, the elastic scatterings of pp and pp at high energies axe studied. The contributions from individual terms of quark-quark, gluon-gluon interactions, quaxk-gluon interference, and the Odderon terms to the nuclear slope parameter B(s) are analyzed. Our results show that the QCD inspired model gives a good fit to the LHC experimental data of the nucleax slope parameter.
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.
Helicity in proton-proton elastic scattering and the spin structure of the pomeron
Ewerz, Carlo; Lebiedowicz, Piotr; Nachtmann, Otto; Szczurek, Antoni
2016-12-01
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.
David Abbott; Abdellah Ahmidouch; Heinz Anklin; Francois Arvieux; Jacques Ball; S. Beedoe; Elizabeth Beise; Louis Bimbot; Werner Boeglin; Herbert Breuer; Roger Carlini; Nicholas Chant; Samuel Danagoulian; K. Dow; Jean-Eric Ducret; James Dunne; Lars Ewell; Laurent Eyraud; Christophe Furget; Michel Garcon; Ronald Gilman; Charles Glashausser; Paul Gueye; Kenneth Gustafsson; Kawtar Hafidi; Adrian Honegger; Juerg Jourdan; Serge Kox; Gerfried Kumbartzki; L. Lu; Allison Lung; David Mack; Pete Markowitz; Justin McIntyre; David Meekins; Fernand Merchez; Joseph Mitchell; R. Mohring; Sekazi Mtingwa; Hamlet Mkrtchyan; David Pitz; Liming Qin; Ronald Ransome; Jean-Sebastien Real; Philip Roos; Paul Rutt; Reyad Sawafta; Samuel Stepanyan; Raphael Tieulent; Egle Tomasi-Gustafsson; William Turchinetz; Kelley Vansyoc; Jochen Volmer; Eric Voutier; William Vulcan; Claude Williamson; Stephen Wood; Chen Yan; Jie Zhao; Wenxia Zhao
2000-05-01
Tensor polarization observables (t20, t21 and t22) have been measured in elastic electron-deuteron scattering for six values of momentum transfer between 0.66 and 1.7 (GeV/c){sup 2}. The experiment was performed at the Jefferson Laboratory in Hall C using the electron HMS Spectrometer, a specially designed deuteron magnetic channel and the recoil deuteron polarimeter POLDER. The new data determine to much larger Q{sup 2} the deuteron charge form factors G{sub C} and G{sub Q}. They are in good agreement with relativistic calculations and disagree with pQCD predictions.
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.
QED radiative corrections for elastic e(mu)p scattering in hadronic variables
Akhundov, A A; Alhendi, H A
2004-01-01
A numerical analysis of QED radiative corrections for elastic e(mu)p cattering in hadronic variables at energies of the current experiment at JLab is performed. The explicit formulas from the review of Akhundov et al. resulting from the integration over the phase space of leptonic variables plus photon are used to obtain the values of the cross sections and the radiative correction factor for unpolarized lepton-proton scattering. Our numerical results agree with the corresponding results arising from the formulas of Afanasev et al.
Helicity in proton–proton elastic scattering and the spin structure of the pomeron
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.
Systematic analysis of α elastic scattering with the São Paulo potential
Charry-Pastrana, F. E.; Pinilla, E. C.
2016-07-01
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 Ni. We find this parameter by fitting the theoretical angular distributions to the experimental cross sections through a χ2 minimization. The Ni and their respective uncertainties, σNi, fall in the range 0.4 ≤ Ni ± σNi ≤ 0.8 for all the systems studied.
Helicity in Proton-Proton Elastic Scattering and the Spin Structure of the Pomeron
Ewerz, Carlo; Nachtmann, Otto; Szczurek, Antoni
2016-01-01
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 r_5 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.
The second Born approximation of electron-argon elastic scattering in a Bichromatic laser field
Zhou, Bin; Wen, Da-Yong
2013-01-01
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 elements numerically. The dependence of differential cross section on the relative phase between the two laser components is presented. The results obtained in the first and second Born approximation are compared and analysed.
200-GeV proton-proton elastic scattering at high transverse momentum
Ratner, L.G.; /Argonne; Krisch, A.D.; Roberts, J.B.; Terwilliger, K.M.; /Michigan U.
1970-06-01
This is a proposal to study p-p elastic scattering at the highest possible P{sub {perpendicular}}{sup 2} at NAL, using a CH{sub 2} or H{sub 2} target placed directly in the extracted beam and a double arm spectrometer. We expect to be able to set an upper limit at the level d{sigma}/dt/d{sigma}/dt{sub t=0} {approx} 10{sup -14}. This would be sufficient to determine if there are exactly three regions in the p-p interaction with considerable precision.
Elastic Scattering of Ultracold 133Cs and 85Rb Atoms in Triplet State
SUN Jin-Feng; HU Qiu-Bo; ZHU Zun-Lue; WANG Xiao-Fei; ZHANG Ji-Cai
2007-01-01
Elastic scattering properties of the ultracold interaction for the triplet state of 133Cs and 85Rb atoms are studied using two kinds of potentials by the same phase Φ. One is the interpolation potential, and another is Lennard-Jones potential (L J12,6). The radial Schr(o)dinger equation is also solved using two computational methods, the semiclassical method (WKB), and the Numerov method. Our results are found to be in an excellent agreement with the more recent theoretical values. It shows that the two potentials and methods are applicable for studying ultracold collisions between the mixing alkali atoms.
Elastic scattering research at a 1 MW long pulse spallation neutron source
Crawford, R.K.
1995-12-31
The elastic scattering working group investigated instrumentation for powder diffraction, single-crystal diffraction, small-angle diffraction, and reflectometry. For this purpose, three subgroups were formed; one for powder diffraction and single-crystal diffraction, one for small-angle diffraction, and one for reflectometry. For the most part these subgroups worked separately, but for part of the time the reflectometry and small-angle diffraction subgroups met together to discuss areas of common interest. Contributors in each of these subgroups are indicated below along with the discussion of these subgroup deliberations.
R-matrix and K-matrix analysis of elastic $\\alpha - \\alpha$ scattering
Humblet, J; Langanke, K
1998-01-01
The R- and K-matrix parametrizations are analyzed and compared for the elastic alpha-alpha scattering at center-of-mass energies below 40 MeV. The two parametrizations differ in their definitions of the resonance energy which can lead to quite different results. The physical values of the best-fit parameters are compared with those computed for a potential model. The existence of a broad resonance near 9 MeV is not supported by the data or by the potential model. We discuss the positive and negative aspects for both parametrizations.
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.
Short Range Correlations in Nuclei at Large xbj through Inclusive Quasi-Elastic Electron Scattering
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
Effect of Dzyaloshinski-Moriya interaction on elastic small-angle neutron scattering
Michels, Andreas; Mettus, Denis; Honecker, Dirk; Metlov, Konstantin L.
2016-08-01
For magnetic materials containing many lattice imperfections (e.g., nanocrystalline magnets), the relativistic Dzyaloshinski-Moriya (DM) interaction may result in nonuniform spin textures due to the lack of inversion symmetry at interfaces. Within the framework of the continuum theory of micromagnetics, we explore the impact of the DM interaction on the elastic magnetic small-angle neutron scattering (SANS) cross section. It is shown that the DM interaction gives rise to a polarization-dependent asymmetric term in the spin-flip SANS cross section. Analysis of this feature may provide a means to determine the DM constant.
Inverse freezing in {alpha}-cyclodextrin solutions probed by quasi elastic neutron scattering
Plazanet, M. [LENS, University of Florence, Via Nello Carrara 1, I-50019 Sesto-Fiorentino (Italy); INFM-CRS-Soft Matter (CNR), c/o Univ. la Sapienza, Piaz. A. Moro 2, I-00185 Roma (Italy); Institut Laue-Langevin, B.P. 156X, 38042 Grenoble Cx (France); Johnson, M.R. [Institut Laue-Langevin, B.P. 156X, 38042 Grenoble Cx (France); Schweins, R. [Institut Laue-Langevin, B.P. 156X, 38042 Grenoble Cx (France); Trommsdorff, H.P. [Institut Laue-Langevin, B.P. 156X, 38042 Grenoble Cx (France); Laboratoire de Spectrometrie Physique, Universite J. Fourier Grenoble - CNRS (UMR 5588), BP 87, 38402 St. Martin d' Heres Cx (France)], E-mail: trommsdorff@ill.fr
2006-12-11
Solutions of {alpha}-cyclodextrin, 4-methylpyridine and water undergo a reversible liquid-solid phase transition on heating ('inverse freezing'). In this paper quasi elastic neutron scattering (QENS) measurements are reported, from which the diffusive dynamics of different components in the liquid and solid phases is determined. Results imply that, in solution, {alpha}-cyclodextrin is contained in a solvation shell of 4-methylpyridine molecules, while in the crystal phase, the majority of the cell contents are immobilized on the nanosecond timescale. This information will be important in evaluating the entropy of the system in its different phases and in understanding the unusual phase transition.
Analyzing power for the proton elastic scattering from neutron-rich 6He nucleus
Uesaka, T; Iseri, Y; Amos, K; Aoi, N; Hashimoto, Y; Hiyama, E; Ichikawa, M; Ichikawa, Y; Ishikawa, S; Itoh, K; Itoh, M; Iwasaki, H; Karataglidis, S; Kawabata, T; Kawahara, T; Kuboki, H; Maeda, Y; Matsuo, R; Nakao, T; Okamura, H; Sakai, H; Sasamoto, Y; Sasano, M; Satou, Y; Sekiguchi, K; Shinohara, M; Suda, K; Suzuki, D; Takahashi, Y; Tanifuji, M; Tamii, A; Wakui, T; Yako, K; Yamamoto, Y; Yamaguchi, M
2010-01-01
Vector analyzing power for the proton-6He elastic scattering at 71 MeV/nucleon has been measured for the first time, with a newly developed polarized proton solid target working at low magnetic field of 0.09 T. The results are found to be incompatible with a t-matrix folding model prediction. Comparisons of the data with g-matrix folding analyses clearly show that the vector analyzing power is sensitive to the nuclear structure model used in the reaction analysis. The alpha-core distribution in 6He is suggested to be a possible key to understand the nuclear structure sensitivity.
Lu, C.; Mao, Z.; Lin, J.; Prakapenka, V.
2011-12-01
Iron-containing pyrope ((Fe,Mg)3Al2Si3O12)) is believed to be an abundant rock-forming mineral in the Earth's interior, ranging from the crust to the top of the lower mantle. Based on the pyrolite mineralogical model, pyrope accounts for 13% by volume in the upper mantle and 10% in the transition zone. Therefore, laboratory measurements on the elasticity of pyrope at relevant pressure and temperature conditions are critical in understanding the seismic images and in constraining the chemistry and mineralogy of the region. The elasticity of single-crystal pyrope has been studied up to 20 GPa at 300 K and up to 1100 K at 1 bar, yet it has never been investigated at simultaneous high pressure-temperature conditions. Thus, much of our knowledge of the upper mantle and transition zone seismic profiles largely relies on extrapolated experimental results or theoretical calculations. Here we have measured the single-crystal elasticity of garnet, ((Mg2.04Ca0.16Fe0.74)Al2.02(SiO4)3) up to 20 GPa and 750 K using combined Brillouin scattering and synchrontron X-ray diffraction in an externally-heated diamond anvil cell at GSECARS of the Advanced Photon Source, Argonne National Laboratory. We have derived full elastic constants (Cij) of the sample as a function of pressure and temperature at relevant conditions of the deep mantle. The temperature derivatives of the Cijs are similar to that at ambient pressure, indicating a minimal pressure effect. Together with the elasticity of other major mantle minerals, we have used a thermoelastic model to reconstruct the seismic velocity profile of the upper mantle and the transition zone and to reference the mineralogy of the regions.
SHI De-Heng; LIU Yu-Fang; SUN Jin-Feng; YANG Xiang-Dong; ZHU Zun-Lue
2005-01-01
@@ The additivity rule model together with the complex optical model potential correlated by the concept of bonded atoms, which considers the overlapping effect of electron clouds between two atoms in a molecule, is firstly employed to calculate the absolute differential cross sections for electrons scattered by carbon monoxide at intermediate and high energies at the Hartree-Fock level. A comparison of elastic differential cross section results, obtained by using the correlated complex optical model potential, with the available experimental data,shows a significant improvement over the uncorrelated ones. The differential cross sections obtained by using the correlated complex optical model potential are in very good agreement with the experimental data. It is shown that the additivity rule model together with the correlated complex optical model potential is suitable for the calculations of the absolute differential cross sections of e-CO scattering.
Total and elastic electron scattering cross sections from Xe at intermediate and high energies
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.
M Sivanantham; B V R Tata
2010-12-01
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 intensity-autocorrelation function for PAAm gel immersed in water and in 5 M NaCl showed an exponential decay to a plateau with an initial decay followed by saturation at long times. The value of the plateau was found to depend on NaCl concentration and was higher than that of water. Collective diffusion coefficient, , of the polymer network of the hydrogel immersed in water and in different concentrations of NaCl was determined by analysing (, ). The measured diffusion coefficient showed linear decrease with increase in concentration of NaCl. The characteristic network parameters were obtained by analyzing (, ) with harmonically bound Brownian particle model and from static light scattering studies.
Model of K/sup +/p elastic scattering at high energies
Fazal-e-Aleem
1985-07-01
Very recent measurements of the angular distribution for K/sup +/p elastic scattering which show a structure near -t = 3.8(GeV/c)/sup 2/, together with the total cross section and ratio of the real and imaginary parts of the scattering amplitude for 50< or =p/sub l/< or =280 GeV/c and with -t extending up to 8 (GeV/c)/sup 2/, have been fitted by using a simple Regge-pole model with phenomenological residue functions. The break in the slope near -t = 0.5 (GeV/c)/sup 2/ observed in the differential cross section has also been explained.
New results for antiproton-proton elastic scattering and various theoretical models
Fazal-e-Aleem; Saleem, M. (Centre for High Energy Physics, Punjab University, Lahore-54590, Pakistan (PK)); Yodh, G.B. (Department of Physics, University of California-Irvine, Irvine, CA 92717 (USA))
1991-07-01
The most recent measurements of the ratio {rho} of the real and imaginary parts of the forward-scattering amplitudes at 0.546 TeV, the total and elastic differential cross sections at 0.546 and 1.8 TeV for proton-antiproton scattering, are compared to the predictions of the generalized Chou-Yang and other theoretical models. For 1.8 TeV, the presence or absence of the break near {minus}{ital t}{approx}0.15 (GeV/{ital c}){sup 2} and of the dip in the vicinity of 0.6 (GeV/{ital c}){sup 2} are also discussed in the light of various predictions. The possibility of a further rise of the ratio {rho} at 1.8 TeV is also probed.
Transverse Target Single Spin Asymmetry in Elastic e-{\\p} Scattering
Alhalholy, Tareq
2016-01-01
Using the Coulomb Eikonal Phase associated with a transversely polarized nucleon, we calculate the azimuthal single spin asymmetry of unpolarized electrons elastically scattered from a transversely polarized nucleon target. The azimuthal asymmetry in this case is attributed to the fact that in a transversely polarized nucleon, the transverse charge density is no longer axially symmetric and is distorted due to the transverse spin of the nucleon. This asymmetry in the nucleon charge density causes a left-right asymmetry in the azimuthal distribution of the scattered electrons. In our approach, we utilize the relativistic Eikonal approximation to calculate the one and two photon exchange amplitudes from which a non zero azimuthal asymmetry appears due to the interference between the two amplitudes.
Metzler, Adam M; Siegmann, William L; Collins, Michael D
2012-02-01
The parabolic equation method with a single-scattering correction allows for accurate modeling of range-dependent environments in elastic layered media. For problems with large contrasts, accuracy and efficiency are gained by subdividing vertical interfaces into a series of two or more single-scattering problems. This approach generates several computational parameters, such as the number of interface slices, an iteration convergence parameter τ, and the number of iterations n for convergence. Using a narrow-angle approximation, the choices of n=1 and τ=2 give accurate solutions. Analogous results from the narrow-angle approximation extend to environments with larger variations when slices are used as needed at vertical interfaces. The approach is applied to a generic ocean waveguide that includes the generation of a Rayleigh interface wave. Results are presented in both frequency and time domains.
Double folding model analysis of elastic scattering of halo nucleus 11Be from 64Zn
M Hemalatha
2014-05-01
Calculations of elastic scattering cross-sections for 9,10,11Be+64Zn at near-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 9,10,11Be projectiles and a 64Zn target are folded with the complex energydependent effective M3Y interaction. The angular distributions of the differential cross-section for 9,10Be scattering from 64Zn at $E_{c.m.} ≈$24.5 MeV agree remarkably well with the data, while in case of 11Be, calculations show a Coulomb–nuclear interference peak which is not observed in the data.
Large Logarithms in the Beam Normal Spin Asymmetry of Elastic Electron--Proton Scattering
Andrei Afanasev; Mykola Merenkov
2004-06-01
We study a parity-conserving single-spin beam asymmetry of elastic electron-proton scattering induced by an absorptive part of the two-photon exchange amplitude. It is demonstrated that excitation of inelastic hadronic intermediate states by the consecutive exchange of two photons leads to logarithmic and double-logarithmic enhancement due to contributions of hard collinear quasi-real photons. The asymmetry at small electron scattering angles is expressed in terms of the total photoproduction cross section on the proton, and is predicted to reach the magnitude of 20-30 parts per million. At these conditions and fixed 4-momentum transfers, the asymmetry is rising logarithmically with increasing electron beam energy, following the high-energy diffractive behavior of total photoproduction cross section on the proton.
New high precision data on the differential cross sections of the pion-proton elastic scattering
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.
Soutas-Little, Robert William
2010-01-01
According to the author, elasticity may be viewed in many ways. For some, it is a dusty, classical subject . . . to others it is the paradise of mathematics."" But, he concludes, the subject of elasticity is really ""an entity itself,"" a unified subject deserving comprehensive treatment. He gives elasticity that full treatment in this valuable and instructive text. In his preface, Soutas-Little offers a brief survey of the development of the theory of elasticity, the major mathematical formulation of which was developed in the 19th century after the first concept was proposed by Robert Hooke
Optical elastic scattering for early label-free identification of clinical pathogens
Genuer, Valentin; Gal, Olivier; Méteau, Jérémy; Marcoux, Pierre; Schultz, Emmanuelle; Lacot, Éric; Maurin, Max; Dinten, Jean-Marc
2016-03-01
We report here on the ability of elastic light scattering in discriminating Gram+, Gram- and yeasts at an early stage of growth (6h). Our technique is non-invasive, low cost and does require neither skilled operators nor reagents. Therefore it is compatible with automation. It is based on the analysis of the scattering pattern (scatterogram) generated by a bacterial microcolony growing on agar, when placed in the path of a laser beam. Measurements are directly performed on closed Petri dishes. The characteristic features of a given scatterogram are first computed by projecting the pattern onto the Zernike orthogonal basis. Then the obtained data are compared to a database so that machine learning can yield identification result. A 10-fold cross-validation was performed on a database over 8 species (15 strains, 1906 scatterograms), at 6h of incubation. It yielded a 94% correct classification rate between Gram+, Gram- and yeasts. Results can be improved by using a more relevant function basis for projections, such as Fourier-Bessel functions. A fully integrated instrument has been installed at the Grenoble hospital's laboratory of bacteriology and a validation campaign has been started for the early screening of MSSA and MRSA (Staphylococcus aureus, methicillin-resistant S. aureus) carriers. Up to now, all the published studies about elastic scattering were performed in a forward mode, which is restricted to transparent media. However, in clinical diagnostics, most of media are opaque, such as blood-supplemented agar. That is why we propose a novel scheme capable of collecting back-scattered light which provides comparable results.
Lepton mass effects in elastic lepton-proton scattering beyond the leading order of QED
Koshchii, Oleksandr; Afanasev, Andrei
2017-01-01
The future MUSE experiment is devised to solve the ``Proton Radius Puzzle'' by considering simultaneously elastic e+/- p and μ+/- p scattering. This experiment requires a per cent level accuracy in comparison of electron-proton and muon-proton scattering. Our goal is to provide all the relevant radiative corrections calculations for MUSE without using ultrarelativistic (ml -> 0) approximation. This approximation is not applicable for the scattering of muons in kinematics of MUSE. In this talk, we will present our up-to-date results on radiative corrections calculations obtained by using a Monte Carlo generator ELRADGEN modified to treat the lepton mass effects with no ultra-relativistic approximation. Next, we will discuss our estimations of the important helicity-flip contribution represented by a scalar σ meson exchange in the t-channel. This term vanishes in the ultra-relativistic and/or one-photon exchange approximation, and makes a difference in comparison of electron vs muon scattering in MUSE. This work was supported by the NSF under Grants Nos. PHY-1404342, PHY-1309130 and by The George Washington University through the Gus Weiss endowment.
Elastic Neutron Scattering at 96 MeV from {sup 12}C and {sup 208}Pb
Klug, J.; Blomgren, J.; Atac, A. [and others
2003-04-01
A facility for detection of scattered neutrons in the energy interval 50-130 MeV, SCANDAL (SCAttered Nucleon Detection AssembLy), has recently been installed at the 20-180 MeV neutron beam line of the The Svedberg Laboratory, Uppsala. Elastic neutron scattering from {sup 12}C and {sup 208}Pb has been studied at 96 MeV in the 10-70 deg interval. The achieved energy resolution, 3.7 MeV, is about an order of magnitude better than for any previous experiment above 65 MeV incident energy. The present experiment represents the highest neutron energy where the ground state has been resolved from the first excited state in neutron scattering. A novel method for normalization of the absolute scale of the cross section has been used. The estimated uncertainty, 3 %, is unprecedented for a neutron-induced differential cross section measurement on a nuclear target. The results are compared with modern optical model predictions, based on phenomenology or microscopic nuclear theory.
Measuring the Weak Charge of the Proton via Elastic Electron-Proton Scattering
Jones, Donald
2016-01-01
The Qweak experiment which ran at Jefferson Lab in Newport News, VA, measured the weak charge of the proton $Q_W^p$ via elastic electron-proton scattering. Longitudinally polarized electrons were scattered from an unpolarized liquid hydrogen target. The Standard Model predicts a small parity-violating asymmetry of scattering rates between electron right and left helicity states due to the weak interaction. An initial result using 4% of the data was published in October 2013 with a measured parity-violating asymmetry of $-279\\pm 35(\\text{stat})\\pm 31$ (syst) parts per billion (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 $Q_W^p=0.064\\pm0.012$, in agreement with the Standard Model prediction of $Q_W^p(SM)=0.0708\\pm0.0003$. The results of the full dataset are expected to decrease the statistical error from the initial publication by a facto...
Measuring the Weak Charge of the Proton via Elastic Electron-Proton Scattering
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].
Chen, Wei-kang; Fang, Hui
2016-03-01
The basic principle of polarization-differentiation elastic light scattering spectroscopy based techniques is that under the linear polarized light incidence, the singlely scattered light from the superficial biological tissue and diffusively scattered light from the deep tissue can be separated according to the difference of polarization characteristics. The novel point of the paper is to apply this method to the detection of particle suspension and, to realize the simultaneous measurement of its particle size and number density in its natural status. We design and build a coaxial cage optical system, and measure the backscatter signal at a specified angle from a polystyrene microsphere suspension. By controlling the polarization direction of incident light with a linear polarizer and adjusting the polarization direction of collected light with another linear polarizer, we obtain the parallel polarized elastic light scattering spectrum and cross polarized elastic light scattering spectrum. The difference between the two is the differential polarized elastic light scattering spectrum which include only the single scattering information of the particles. We thus compare this spectrum to the Mie scattering calculation and extract the particle size. We then also analyze the cross polarized elastic light scattering spectrum by applying the particle size already extracted. The analysis is based on the approximate expressions taking account of light diffusing, from which we are able to obtain the number density of the particle suspension. We compare our experimental outcomes with the manufacturer-provided values and further analyze the influence of the particle diameter standard deviation on the number density extraction, by which we finally verify the experimental method. The potential applications of the method include the on-line particle quality monitoring for particle manufacture as well as the fat and protein density detection of milk products.
Elastic neutron scattering study of water dynamics in ion-exchanged type-A zeolites.
Corsaro, C; Crupi, V; Longo, F; Majolino, D; Venuti, V; Wanderlingh, U
2005-12-01
With the aim to investigate, by means of elastic neutron scattering, the effects produced by the cation substitution on the dynamics of water in zeolites, we measured, using a neutron backscattering spectrometer, the temperature dependence of mean-square atomic displacements [u2] derived from window integrated quasielastic spectra of fully and partially hydrated Na-A and Mg50-A zeolites. The results, collected in the 20-273 K temperature range, reveal that, at low temperature, the [u2] shows a harmonic trend independent of hydration and cation substitution, and, at higher temperatures, the onset of a non-Gaussian dynamics of the elastic intensity. This latter takes place at T approximately 200 K and approximately 150 K for fully and partially hydrated samples, respectively. This behavior has been interpreted in terms of reorientational jumps of H atoms described by two-site processes within an asymmetric double-minimum potential. In spite of its simplicity, the model seems to reproduce the rearrangement of the hydrogen bond network of zeolitic water. The fit results indicate a reduced proton mobility by diminishing the water content and by the induced Na+-->Mg2+ ion exchange, in agreement with previous incoherent quasielastic neutron scattering results at higher temperatures.
πN Elastic Scattering and Resonances in Quark Potential Model
CHEN Ju-Mei; WANG Hai-Jun; LI Cheng-Zu; SU Jun-Chen; LIANG Lin-Mei; CHEN Ping-Xing; DAI Hong-Yi
2008-01-01
The quark potential model is used to investigate the low-energy elastic scattering of π N system. The model potential consists of the t-channel and s-channel one-gluon exchange potentials and the harmonic oscillator confining potential. By means of the resonating group method, a nonlocal effective potential for the πN system is derived from the interquark potentials and used to calculate the π N elastic scattering phase shifts. By considering the effect of QCD renormalization, the suppression of the spin-orbital coupling and the contribution of the color octet of the clusters (qq) and (qqq), the numerical results are in fairly good agreement with the experimental data. The same model and method are employed to investigate the possible πN resonances. For this purpose, the resonating group equation is transformed into a standard Schrodinger equation in which the nonlocal effective πN interaction potential is included. Solving the Schrodinger equation by the variational method, we are able to reproduce the masses of some currently concerned πN resonances.
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.
Fedus, Kamil
2016-12-01
A simple potential model of a rigid sphere combined with an adiabatic dipole polarization ( r -4) is tested for positron-atom and positron-molecule elastic collisions. The numerical model, which is based on the analytical solution of radial Schrödinger equation for r -4 potential, depends solely upon the average dipole polarizability of the target and one adjustable parameter - the radius of a hard core. The validity of model is assessed by an extensive comparative study against numerous experimental cross-sections and theoretical phase-shifts of angular momentum partial waves for positrons scattered elastically by He, Ne, Ar, Kr, Xe, H2, N2 and CH4. In particular it is shown that this very simple approach can be used to model positron elastic collisions with targets characterized by moderate dipole polarizabilities (Ar, Kr, H2, N2) in good agreement with experiments for impact energies covering almost entire range from the positronium formation threshold down to the zero energy.
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.
ZHAO Jia-xi; QI Hui; SU Sheng-wei
2008-01-01
Scattering of SH wave from an interface cylindrical elastic inclusion with a semicircular disconnected curve is investigated.The solution of dynamic stress concentration factor is given using the Gteen's function and the method of complex variable functions.First,the space is divided into upper and lower parts along the interface.In the lower half space,a suitable Green's function for the problem is constructed.It is an essential solution of the displacement field for an elastic half space with a semi-cylindrical hill of cylindrical elastic inclusion while bearing out-plane harmonic line source load at the horizontal surface.Thus,the semicircular disconnected curve can be constructed when the two parts are bonded and continuous on the interface loading the undetermined anti-plane forces on the horizontal surfaces.Also,the expressions of displacement and stress fields are obtained in this situation.Finally,examples and results of dynamic stress concentration factor are given.Influences of the cylindrical inclusion and the difierence parameters of the two mediators are discussed.
Is a nucleon core being seen in high-energy elastic pp scattering at large momentum transfer?
Islam, M M
1978-01-01
Recently proton-proton elastic scattering has been measured at CERN ISR for the equivalent laboratory energy 1496 GeV and at Fermilab for the laboratory energy 201 GeV to probe the momentum transfer region -t (4-12)/(GeV/c)/sup 2/. The new data show a number of distinctive features which presently popular models of diffraction cannot explain. The authors show that a model of pp elastic scattering suggested earlier to explain the scattering data at the lower energies (1969) provides a satisfactory agreement with the features of the new data qualitatively as well as quantitatively. In the model besides diffraction a hard-scattering process originating from the existence of a nucleon core is envisaged. The hard process is regarded as responsible for the large momentum transfer scattering and the Orear exponential fall-off of d sigma /dt. (19 refs).
Multilevel fast multipole algorithm for elastic wave scattering by large three-dimensional objects
Tong, Mei Song; Chew, Weng Cho
2009-02-01
Multilevel fast multipole algorithm (MLFMA) is developed for solving elastic wave scattering by large three-dimensional (3D) objects. Since the governing set of boundary integral equations (BIE) for the problem includes both compressional and shear waves with different wave numbers in one medium, the double-tree structure for each medium is used in the MLFMA implementation. When both the object and surrounding media are elastic, four wave numbers in total and thus four FMA trees are involved. We employ Nyström method to discretize the BIE and generate the corresponding matrix equation. The MLFMA is used to accelerate the solution process by reducing the complexity of matrix-vector product from O(N2) to O(NlogN) in iterative solvers. The multiple-tree structure differs from the single-tree frame in electromagnetics (EM) and acoustics, and greatly complicates the MLFMA implementation due to the different definitions for well-separated groups in different FMA trees. Our Nyström method has made use of the cancellation of leading terms in the series expansion of integral kernels to handle hyper singularities in near terms. This feature is kept in the MLFMA by seeking the common near patches in different FMA trees and treating the involved near terms synergistically. Due to the high cost of the multiple-tree structure, our numerical examples show that we can only solve the elastic wave scattering problems with 0.3-0.4 millions of unknowns on our Dell Precision 690 workstation using one core.
李凤明; 胡超; 徐敏强; 黄文虎
2003-01-01
Based on the theory of elastic dynamics,multiple scattering of elastic waves and dynamic stress concentrations in fiber-reinforced composite are studied.The analytical expressions of elastic waves in different regions are presented.The mode coefficients of elastic waves are determined in accordance with the continuous conditions of displacement and stress on the boundary of the multiinterfaces.By using the addition theorem of Hankel functions,the formula of scattered wave fields in different local coordinates are transformed into those in one local coordinate to determine the unknown coefficients and dynamic stress concentration factors (DSCFs).The influences of the distance between two inclusions,material properties and structural size on the DSCFs near the interfaces are analyzed.As examples,the numerical results of DSCFs near the interfaces for two kinds of fiber-reinforced composites are presented and discussed.
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.
Elastic scattering and breakup of 11Be on deuterons at 26.9 A MeV
Chen, J.; Lou, J. L.; Ye, Y. L.; Rangel, J.; Moro, A. M.; Pang, D. Y.; Li, Z. H.; Ge, Y. C.; Li, Q. T.; Li, J.; Jiang, W.; Sun, Y. L.; Zang, H. L.; Zhang, Y.; Aoi, N.; Ideguchi, E.; Ong, H. J.; Lee, J.; Wu, J.; Liu, H. N.; Wen, C.; Ayyad, Y.; Hatanaka, K.; Tran, T. D.; Yamamoto, T.; Tanaka, M.; Suzuki, T.; Nguyen, T. T.
2016-12-01
The elastic scattering and breakup reactions of the halo nucleus 11Be on deuterons at an incident energy of 26.9 A MeV are reported for the first time. Special attention has been paid to the determination and subtraction of the proton contaminations in the deuterated polyethylene (CD2)n target (where D2 denotes H22 ). The cross sections for elastic scattering are analyzed with the systematic optical potentials of Daehnick et al. and DA1p, as well as with single-folding potentials, derived from the Jeukenne-Lejeune-Mahaux effective nucleon-nucleon interaction. An extended version of the continuum-discretized coupled-channels (XCDCC) formalism, including dynamic core excitation (DCX) effects, is applied to analyze the elastic scattering and breakup data. Comparisons of the full XCDCC calculation with that omitting DCX effects indicate that the core excitation plays a remarkable role in reproducing breakup reactions of 11Be+d .
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.
Plane wave method for elastic wave scattering by a heterogeneous fracture
Nakagawa, Seiji; Nihei, Kurt T.; Myer, Larry R.
2003-02-21
A plane-wave method for computing the three-dimensional scattering of propagating elastic waves by a planar fracture with heterogeneous fracture compliance distribution is presented. This method is based upon the spatial Fourier transform of the seismic displacement-discontinuity (SDD) boundary conditions (also called linear slip interface conditions), and therefore, called the wave-number-domain SDD method (wd-SDD method). The resulting boundary conditions explicitly show the coupling between plane waves with an incident wave number component (specular component) and scattered waves which do not follow Snell's law (nonspecular components) if the fracture is viewed as a planar boundary. For a spatially periodic fracture compliance distribution, these boundary conditions can be cast into a linear system of equations that can be solved for the amplitudes of individual wave modes and wave numbers. We demonstrate the developed technique for a simulated fracture with a stochastic (correlated) surface compliance distribution. Low- and high-frequency solutions of the method are also compared to the predictions by low-order Born series in the weak and strong scattering limit.
Elastic pion-nucleon scattering in chiral perturbation theory: A fresh look
Siemens, D.; Bernard, V.; Epelbaum, E.; Gasparyan, A.; Krebs, H.; Meißner, Ulf-G.
2016-07-01
Elastic pion-nucleon scattering is analyzed in the framework of chiral perturbation theory up to fourth order within the heavy-baryon expansion and a covariant approach based on an extended on-mass-shell renormalization scheme. We discuss in detail the renormalization of the various low-energy constants and provide explicit expressions for the relevant β functions and the finite subtractions of the power-counting breaking terms within the covariant formulation. To estimate the theoretical uncertainty from the truncation of the chiral expansion, we employ an approach which has been successfully applied in the most recent analysis of the nuclear forces. This allows us to reliably extract the relevant low-energy constants from the available scattering data at low energy. The obtained results provide clear evidence that the breakdown scale of the chiral expansion for this reaction is related to the Δ resonance. The explicit inclusion of the leading contributions of the Δ isobar is demonstrated to substantially increase the range of applicability of the effective field theory. The resulting predictions for the phase shifts are in an excellent agreement with the predictions from the recent Roy-Steiner-equation analysis of pion-nucleon scattering.
The contribution of small angle and quasi-elastic scattering to the physics of liquid water
Teixeira, José
2017-05-01
Many properties of liquid water at low temperature show anomalous behaviour. For example, density, isothermal compressibility, heat capacity pass by maxima or minima and transport properties show a super-Arrhenius behaviour. Extrapolations performed beyond the homogeneous nucleation temperature are at the origin of models that predict critical points, liquid-liquid transitions or dynamic cross-overs in the large domain of temperature and pressure not accessible to experiments because of ice nucleation. A careful analysis of existing data can be used to test some of these models. Small angle X-ray or neutron scattering data are incompatible with models where two liquids or heterogeneities are present. Quasi-elastic neutron scattering, taking advantage and combining both coherent and incoherent scattering show that two relaxation times are present in liquid water and that one of them, related to hydrogen bond dynamics, has an Arrhenian behaviour, suggesting that the associated dynamics of the bonds, similar to the β relaxation of polymers, determines the glass transition temperature of water.
Pakou, A.; Keeley, N.; Pierroutsakou, D.; Mazzocco, M.; Acosta, L.; Aslanoglou, X.; Boiano, A.; Boiano, C.; Carbone, D.; Cavallaro, M.; Grebosz, J.; La Commara, M.; Manea, C.; Marquinez-Duran, G.; Martel, I.; Parascandolo, C.; Rusek, K.; Sánchez-Benítez, A. M.; Sgouros, O.; Signorini, C.; Soramel, F.; Soukeras, V.; Stiliaris, E.; Strano, E.; Torresi, D.; Trzcińska, A.; Watanabe, Y. X.; Yamaguchi, H.
2015-07-01
Quasi-elastic scattering data were obtained for the radioactive nucleus 8Li on a 90Zr target at the near-barrier energy of 18.5MeV over the angular range to 80°. They were analyzed within the coupled channels and coupled reaction channels frameworks pointing to a strong coupling effect for single neutron stripping, in contrast to 6, 7 Li + 90 Zr elastic scattering at similar energies, a non-trivial result linked to detailed differences in the structure of these Li isotopes.
Elastic scattering of the halo nucleus 6 He from 197 Au at Elab=27 MeV
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 .
Elastic scattering of the halo nucleus 6 He from 197 Au at Elab=27 MeV
Kakuee, O. R.; Rahighi, J.; Afarideh, H.; Cherubini, S.; Davinson, T.; Galster, W.; Laird, A M; Lamehi-Rachti, M.; P. Oliaiy; Shotter, A.C.; F. Shokouhi; Smith, W.B.
2003-01-01
A radioactive ion beam of 6He produced via the 7Li(p,2p)6He 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 .
Results for quasi-elastic anti-neutrino scattering on scintillator from the MINERvA experiment
Schellman, Heidi; Minerva Collaboration
2016-09-01
We present a new preliminary measurement of the charge-current quasi-elastic scattering cross section for anti-neutrinos on scintillator (CH) over the energy range 1.5-10 GeV. The data were taken with the MINERvA detector in the NuMI beamline at Fermilab and cover the energy range of interest for the proposed DUNE long-baseline neutrino oscillation experiment and of JLAB elastic scattering experiments. Of particular interest to the nuclear community are possible signatures for short range correlations and/or meson exchange currents in these data. We present comparisons to a range of nuclear models.
I Ahmad; M R Arafah
2006-03-01
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 that it provides an exceedingly good fit to the pion-carbon data. The proposed elastic -matrix gives a closed expression for the pion-12C optical potential by the method of inversion in the high energy approximation.
Elastic and inelastic scattering of {sup 15}N ions by {sup 9}Be at 84 MeV
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.
Elastic and inelastic scattering of {sup 14}C + {sup 11}B versus {sup 12,13}C + {sup 11}B
Mezhevych, S.Yu.; Rudchik, A.T.; Rudchik, A.A. [Institute for Nuclear Research, Kyiv (Ukraine); Rusek, K. [National Institute for Nuclear Research, Warsaw (Poland); Heavy Ion Laboratory of Warsaw University, Warsaw (Poland); Kemper, K.W. [Florida State University, Physics Department, Tallahassee, Florida (United States); Kliczewski, S.; Czech, B.; Siudak, R.; Szczurek, A. [H. Niewodniczanski Institute of Nuclear Physics, Cracow (Poland); Koshchy, E.I. [Kharkiv National University, Kharkiv (Ukraine); Sakuta, S.B. [Russian Research Center ' ' Kurchatov Institute' ' , Moscow (Russian Federation); Choinski, J. [Heavy Ion Laboratory of Warsaw University, Warsaw (Poland)
2014-01-15
Complete angular distributions of the {sup 14}C + {sup 11}B elastic and inelastic scattering at the energy E{sub lab}({sup 11}B) = 45 MeV were measured for the ground and excited states of {sup 11}B. The data were analyzed within the optical model and the coupled-reaction-channels method. The parameters of the {sup 14}C + {sup 11}B optical potential and {sup 11}B deformation were deduced. The contributions of one- and two-step transfers of nucleons and clusters into the {sup 14}C + {sup 11}B elastic and inelastic scattering were calculated. The isotopic differences between the {sup 14}C + {sup 11}B and {sup 12,13}C + {sup 11}B scatterings are presented and clearly show the importance of the large angle scattering data for understanding the interaction between light heavy ions. (orig.)
Measurement of the analysing power in proton–proton elastic scattering at small angles
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.
Energy dependence of slope parameter in elastic nucleon-nucleon scattering
Okorokov, V A
2015-01-01
The study of slope parameter is presented for elastic proton-proton and antiproton-proton scattering with taking into account the resent experimental data at high energies. The expanded logarithmic approximations allow the description of the experimental slopes in all available energy range reasonably. Accounting for the LHC results leads to the dramatic change of behavior of the quadratic in logarithm approximation at high energies and to the closer trends for all fitting functions under study in comparison with the analysis at collision energies up to the 200 GeV. The estimations of the asymptotic shrinkage parameter $\\alpha'_{\\cal{P}}$ are discussed. Predictions for diffraction slope parameter are obtained for some proton-proton and antiproton-proton facilities.
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.
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.
mQfit, a new program for analyzing quasi-elastic neutron scattering data
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.
Beggio, P C; Valin, P
2000-01-01
Starting from a short range expansion of the inelastic overlap function, capable of describing quite well the elastic pp and $\\bar{p}p$ scattering data, we obtain extensions to the inelastic channel, through unitarity and an impact parameter approach. Based on geometrical arguments we infer some characteristics of the elementary hadronic process and this allows an excellent description of the inclusive multiplicity distributions in $pp$ and $\\bar{p}p$ collisions. With this approach we quantitatively correlate the violations of both geometrical and KNO scaling in an analytical way. The physical picture from both channels is that the geometrical evolution of the hadronic constituents is principally reponsible for the energy dependence of the physical quantities rather than the dynamical (elementary) interaction itself.
{ital S}-matrix analysis of heavy-ion elastic scattering
Chiste, V.; Lichtenthaeler, R.; Villari, A.C.; Gomes, L.C. [Departamento de Fisica Nuclear, Laboratorio do Pelletron, Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318, 05389-970 - Sao Paulo, SP, (Brasil)
1996-08-01
A procedure to minimize {chi}{sup 2} is described which explores the fact that the {chi}{sup 2} distribution is of the fourth degree in the {ital S}-matrix elements. The fact that all three roots of the scale parameter for the minimum of {chi}{sup 2} in its gradient direction are algebraically determined gives the present procedure some global features that previous methods did not contemplate. The automatic search procedure also preserves the unitary bound constraint of the {ital S}-matrix at every step. When the search in the gradient direction slows down, the procedure reverts to the traditional quadratic approximation with zero-order regularization. The method is applied to the elastic scattering of the {sup 12}C+{sup 16}O reaction near the Coulomb barrier. {copyright} {ital 1996 The American Physical Society.}
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.
Mchedlishvili, D; Dymov, S; Bagdasarian, Z; Barsov, S; Gebel, R; Gou, B; Hartmann, M; Kacharava, A; Keshelashvili, I; Khoukaz, A; Kulessa, P; Kulikov, A; Lehrach, A; Lomidze, N; Lorentz, B; Maier, R; Macharashvili, G; Merzliakov, S; Mikirtychyants, S; Nioradze, M; Ohm, H; Prasuhn, D; Rathmann, F; Serdyuk, V; Schroer, D; Shmakova, V; Stassen, R; Stein, H J; Stockhorst, H; Strakovsky, I I; Ströher, H; Tabidze, M; Täschner, A; Trusov, S; Tsirkov, D; Uzikov, Yu; Valdau, Yu; Wilkin, C; Workman, R L; Wüstner, P
2015-01-01
The differential cross section for proton-proton elastic scattering has been measured at a beam energy of 1.0 GeV and in 200 MeV steps from 1.6 to 2.8 GeV for centre-of-mass angles in the range from 12-16 degrees to 25-30 degrees, depending on the energy. Absolute normalisations of typically 3% were achieved by studying the energy losses of the circulating beam of the COSY storage ring as it passed repeatedly through the windowless hydrogen target of the ANKE magnetic spectrometer. It is shown that the data have a significant impact upon a partial wave analysis. After extrapolating the differential cross sections to the forward direction, the results are broadly compatible with the predictions of forward dispersion relations.
On the phase-shift parameterization and ANC extraction from elastic-scattering data
Suárez, Oscar Leonardo Ramírez
2016-01-01
We develop a method to parameterize elastic-scattering phase-shifts for charged nuclei, based on Pad\\'e expansions of a simplified effective-range function. The method is potential independent and the input is reduced to experimental phase shifts and bound-state energies. It allows a simple calculation of resonance properties and of asymptotic normalization constants (ANCs) of subthreshold bound states. We analyze the $1^-$ and $2^+$ phase shifts of the $^{12}$C$+\\alpha$ system and extract the ANCs of the corresponding bound states. For the $1^-$ state, a factor-3 improvement with respect to the best value available today is obtained, with a factor-10 improvement in reach. For the $2^+$ state, no improvement is obtained due to relatively larger error bars on the experimental phase shifts.
D. Mchedlishvili
2016-04-01
Full Text Available The differential cross section for proton–proton elastic scattering has been measured at a beam kinetic energy of 1.0 GeV and in 200 MeV steps from 1.6 to 2.8 GeV for centre-of-mass angles in the range from 12°–16° to 25°–30°, depending on the energy. A precision in the overall normalisation of typically 3% was achieved by studying the energy losses of the circulating beam of the COSY storage ring as it passed repeatedly through the windowless hydrogen target of the ANKE magnetic spectrometer. It is shown that the data have a significant impact upon the results of a partial wave analysis. After extrapolating the differential cross sections to the forward direction, the results are broadly compatible with the predictions of forward dispersion relations.
Quasi-elastic neutron scattering study of dynamics in condensed matter
S Mitra; R Mukhopadhyay
2004-07-01
Quasi-elastic neutron scattering (QENS) technique, known to study stochastic motions has been successfully used to elucidate the molecular motions and physical properties related to them, in a variety of systems. QENS is a unique technique that provides information on the time-scale of the motion as well as the geometry of the motions. In this paper, results of some of the systems studied using the facility available at Dhruva, Trombay and other mega-facilities are discussed. Emphasis is given on the results obtained from three different systems studied using QENS, namely, (1) alkyl chain motions in monolayer protected metal clusters, (2) molecular motions of propane in Na-Y zeolitic systems and (3) the study of reorientational motions of liquid crystal in O. series in different mesophases.
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.
Quasi-elastic light scattering of platinum dendrimer-encapsulated nanoparticles.
Wales, Christina H; Berger, Jacob; Blass, Samuel; Crooks, Richard M; Asherie, Neer
2011-04-05
Platinum dendrimer-encapsulated nanoparticles (DENs) containing an average 147 atoms were prepared within sixth-generation, hydroxyl-terminated poly(amidoamine) dendrimers (G6-OH). The hydrodynamic radii (R(h)) of the dendrimer/nanoparticle composites (DNCs) were determined by quasi-elastic light scattering (QLS) at high (pH ∼10) and neutral pH for various salt concentrations and identities. At high pH, the size of the DNC (R(h) ∼4 nm) is close to that of the empty dendrimer. At neutral pH, the size of the DNC approximately doubles (R(h) ∼8 nm) whereas that of the empty dendrimer remains unchanged. Changes in ionic strength also alter the size of the DNCs. The increase in size of the DNC is likely due to electrostatic interactions involving the metal nanoparticle.
Eikonal analysis of Coulomb distortion in quasi-elastic electron scattering
Tjon, J A
2008-01-01
An eikonal expansion is used to provide systematic corrections to the eikonal approximation through order $1/k^2$, where $k$ is the wave number. Electron wave functions are obtained for the Dirac equation with a Coulomb potential. They are used to investigate distorted-wave matrix elements for quasi-elastic electron scattering from a nucleus. A form of effective-momentum approximation is obtained using trajectory-dependent eikonal phases and focusing factors. Fixing the Coulomb distortion effects at the center of the nucleus, the often-used ema approximation is recovered. Comparisons of these approximations are made with full calculations using the electron eikonal wave functions. The ema results are found to agree well with the full calculations.
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.
Khurgin, Jacob B.; Bajaj, Sanyam; Rajan, Siddharth
2015-12-01
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.
Fully microscopic description of elastic and inelastic scattering at intermediate incident energies
Minomo Kosho
2016-01-01
Full Text Available We aim for fully microscopic understanding of many-body nuclear reactions starting from two- and three-nucleon forces based on chiral effective field theory (Ch-EFT. We first construct a g-matrix with the nuclear forces based on Ch-EFT using Brueckner-Hartree-Fock theory, in which the three-nucleon force effects are represented through the density dependence of the g-matrix. Then, the folding model and microscopic coupled-channels method with the g-matrix are applied to nucleon-nucleus and nucleus-nucleus scattering at intermediate incident energies. This new microscopic framework well describes the elastic and inelastic cross sections with no ad-hoc parameters. In addition, the three-nucleon force and coupled-channels effects on many-body nuclear reactions are clarified.
Microscopic study of {sup 6}He elastic scattering around the Coulomb barrier
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.
Anjos, R.M.; Muri, C.; Moraes, S.B.; Cabezas, R.; Gomes, P.R.S.; Tenreiro, C.; Liguori Neto, R.; Maciel, A.M.M.; Santos, G.M. [Instituto de Fisica, Universidade Federal Fluminense, Av. Litoranea s/n, Gragoata, Niteroi, RJ, 24210-340 (Brazil)
1997-10-01
We present examples of situations where the absence of a simultaneous analysis of the scattering and reaction mechanisms leads to an incomplete or even false understanding of these processes. The optical model analysis of the elastic scattering gives rise to different values of reaction cross sections, while the simple analysis of the fusion excitation functions may lead to ambiguous or wrong conclusions. Data for the {sup 14}N+{sup 59}Co system obtained by our group is used in the analysis. (author)
Elsener, K.; Grueebler, W.; Sperisen, F.; Ghazi-Wakili, K.; Koenig, V.; Schmelzbach, P.A.; Vuaridel, B.; Bittcher, M.; Singy, D.; Ulbricht, J.
1988-05-02
Six polarization transfer coefficients of the d-..cap alpha.. elastic scattering have been measured at an incident deuteron energy of 11.9 MeV and a scattering angle theta/sub lab/ = 37.3/sup 0/. Together with earlier data on cross section and analyzing powers, a complete set of measurements allows to deduce the d-..cap alpha.. M-matrix directly from experiment.
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.
Magazó, Salvatore; Migliardo, Federica; Benedetto, Antonio
2012-10-01
Recently [S. Magazù et al., Rev. Sci. Instrum. 82, 105115 (2011), 10.1063/1.3641870] we have proposed a new method for characterizing, by neutron scattering, the dynamical properties of complex material systems, such as, the ones of interest in the biophysical field. This approach called Resolution Elastic Neutron Scattering, in short RENS, is based on the detection of the elastically scattered neutron intensity as a function of the instrumental energy resolution. By experimental, theoretical, and numerical findings, we have pointed out that an inflection point occurs in the elastic intensity when the system relaxation time approaches the instrumental energy resolution time. This approach, differently from quasi-elastic neutron scattering (QENS), gives the chance to evaluate the system relaxation times without using pre-defined models that can be wrong and/or misleading. Here, we reply to a Comment on the above-mentioned main paper in which Wuttke proposes a different approach to evaluate the above-mentioned inflection point; on this regard, it should be noticed that the existence of the inflection point, which is the main topic of our work, is not questioned and that the approach proposed by Wuttke in the Comment, although valid for a class of dynamical processes, is not applicable when different and distinct processes occur simultaneously at different time scale.
Magazu, Salvatore; Migliardo, Federica; Benedetto, Antonio [Dipartimento di Fisica, Universita di Messina, C.da Papardo n Degree-Sign 31, P.O. Box 55, Vill. S. Agata 98166 Messina (Italy)
2012-10-15
Recently [S. Magazu et al., Rev. Sci. Instrum. 82, 105115 (2011)] we have proposed a new method for characterizing, by neutron scattering, the dynamical properties of complex material systems, such as, the ones of interest in the biophysical field. This approach called Resolution Elastic Neutron Scattering, in short RENS, is based on the detection of the elastically scattered neutron intensity as a function of the instrumental energy resolution. By experimental, theoretical, and numerical findings, we have pointed out that an inflection point occurs in the elastic intensity when the system relaxation time approaches the instrumental energy resolution time. This approach, differently from quasi-elastic neutron scattering (QENS), gives the chance to evaluate the system relaxation times without using pre-defined models that can be wrong and/or misleading. Here, we reply to a Comment on the above-mentioned main paper in which Wuttke proposes a different approach to evaluate the above-mentioned inflection point; on this regard, it should be noticed that the existence of the inflection point, which is the main topic of our work, is not questioned and that the approach proposed by Wuttke in the Comment, although valid for a class of dynamical processes, is not applicable when different and distinct processes occur simultaneously at different time scale.
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.
Low-energy electron elastic scattering from Os atom: New electron affinity
Felfli, Z.; Kiros, F.; Msezane, A. Z.
2013-05-01
Bilodeau and Haugan measured the binding energies (BEs) of the ground state and the excited state of the Os- ion to be 1.07780(12) eV and 0.553(3) eV, respectively. These values are consistent with those calculated in. Here our investigation, using the recent complex angular momentum methodology wherein is embedded the crucial electron-electron correlations and the vital core polarization interaction, has found that the near threshold electron-Os elastic scattering total cross section (TCS) is characterized by three stable bound states of the Os- ion formed as resonances during the slow electron collision, with BEs of 1.910 eV, 1.230 eV and 0.224 eV. The new extracted electron affinity (EA) value from the TCS of 1.910 eV for the Os atom is significantly different from that measured in. Our calculated elastic differential cross sections (DCSs) also yield the relevant BEs for the ground and the two excited states of the Os- ion. The complex characteristic resonance structure in the TCS for the Os atom is ideal for catalysis, but makes it difficult to execute the Wigner threshold law in describing the threshold detachment behavior of complex atoms and extracting the reliable attendant EAs. Supported by U.S. DOE, AFOSR and CAU CFNM, NSF-CREST Program.
Feng, X.; Lorton, C.
2017-03-01
This paper develops and analyzes an efficient Monte Carlo interior penalty discontinuous Galerkin (MCIP-DG) method for elastic wave scattering in random media. The method is constructed based on a multi-modes expansion of the solution of the governing random partial differential equations. It is proved that the mode functions satisfy a three-term recurrence system of partial differential equations (PDEs) which are nearly deterministic in the sense that the randomness only appears in the right-hand side source terms, not in the coefficients of the PDEs. Moreover, the same differential operator applies to all mode functions. A proven unconditionally stable and optimally convergent IP-DG method is used to discretize the deterministic PDE operator, an efficient numerical algorithm is proposed based on combining the Monte Carlo method and the IP-DG method with the $LU$ direct linear solver. It is shown that the algorithm converges optimally with respect to both the mesh size $h$ and the sampling number $M$, and practically its total computational complexity is only amount to solving very few deterministic elastic Helmholtz equations using the $LU$ direct linear solver. Numerically experiments are also presented to demonstrate the performance and key features of the proposed MCIP-DG method.
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...
Simulation and analysis of 13N+p elastic resonance scattering
WANG You-Bao; QIN Xing; WANG Bao-Xiang; LIU Wei-Ping; LI Zhi-Hong; BAI Xi-Xiang; LIAN Gang; GUO Bing; ZENG Sheng; SU Jun; LI Yun-Ju; JIANG Chao
2009-01-01
The 13N+p elastic resonance scattering has been studied at the secondary radioactive beam facility of CIAE in inverse kinematics via a thick-target method. The excitation function for the 13N(p,p) scattering was obtained in the energy interval of Ecm ≈0.5--3.2 MeV with a 13N secondary beam of (47.8±1.5) MeV. Carefulanalysis of the secondary beam components and extensive Monte-Carlo simulations enable the resolution of the experimental proton spectra. The resonance parameters for five low-lying levels in 140 were deduced by R- matrix fitting calculations with MULTI7 and SAMMY-M6-BETA. The present results show general agreement with those from a recent similar work, and thus confirm the observation of a new 0- level at 5.7 MeV in 14O with an improved width of 400(45) keV.
Khazaie, Shahram; Cottereau, Régis; Clouteau, Didier
2016-05-01
In the weakly heterogeneous regime of elastic wave propagation through a random medium, transport and diffusion models for the energy densities can be set up. In the isotropic case, the scattering cross sections are explicitly known as a function of the wavenumber and the correlations of the Lamé parameters and density. In this paper, we discuss the precise influence of the correlation structure on the scattering cross sections, mean free paths and diffusion parameter, and separate that influence from that of the correlation length and variance. We also analyze the convergence rates towards the low- and high-frequency ranges. For all analyses, we consider five different correlation structures that allow us to explore a wide range of behaviors. We identify that the controlling factors for the low-frequency behavior are the value of the Power Spectral Density Function (PSDF) and its first non-vanishing derivative at the origin. In the high frequency range, the controlling factor is the third moment of the PSDF (which may be unbounded).
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.
Optical elastic scattering for early label-free identification of clinical pathogens
Genuer, Valentin; Méteau, Jérémy; Marcoux, Pierre; Schultz, Emmanuelle; Lacot, Éric; Maurin, Max; Dinten, Jean-Marc
2016-01-01
We report here on the ability of elastic light scattering in discriminating Gram+, Gram-and yeasts at an early stage of growth (6h). Our technique is non-invasive, low cost and does require neither skilled operators nor reagents. Therefore it is compatible with automation. It is based on the analysis of the scattering pattern (scatterogram) generated by a bacterial microcolony growing on agar, when placed in the path of a laser beam. Measurements are directly performed on closed Petri dishes. The characteristic features of a given scatterogram are first computed by projecting the pattern onto the Zernike orthogonal basis. Then the obtained data are compared to a database so that machine learning can yield identification result. A 10-fold cross-validation was performed on a database over 8 species (15 strains, 1906 scatterograms), at 6h of incubation. It yielded a 94% correct classification rate between Gram+, Gram-and yeasts. Results can be improved by using a more relevant function basis for projections, suc...
Elastic pion-nucleon scattering in chiral perturbation theory: A fresh look
Siemens, D; Epelbaum, E; Gasparyan, A; Krebs, H; Meißner, Ulf-G
2016-01-01
Elastic pion-nucleon scattering is analyzed in the framework of chiral perturbation theory up to fourth order within the heavy-baryon expansion and a covariant approach based on an extended on-mass-shell renormalization scheme. We discuss in detail the renormalization of the various low-energy constants and provide explicit expressions for the relevant $\\beta$-functions and the finite subtractions of the power-counting breaking terms within the covariant formulation. To estimate the theoretical uncertainty from the truncation of the chiral expansion, we employ an approach which has been successfully applied in the most recent analysis of the nuclear forces. This allows us to reliably extract the relevant low-energy constants from the available scattering data at low energy. The obtained results provide a clear evidence that the breakdown scale of the chiral expansion for this reaction is related to the $\\Delta$-resonance. The explicit inclusion of the leading contributions of the $\\Delta$-isobar is demonstrat...
Ratios of Elastic Scattering of Pions from 3H and 3He
Briscoe, W J; Carter, R W C; Dhuga, K S; Matthews, S K; Nicholas, N J; Greene, S J; Nefkens, B M K; Price, J W; Isenhower, L D; Sadler, M E; Slaus, I; Supek, I
2002-01-01
We have measured the elastic-scattering ratios of normalized yields for charged pions from 3H and 3He in the backward hemisphere. At 180 MeV, we completed the angular distribution begun with our earlier measurements, adding six data points in the angular range of 119 deg to 169 deg in the pi-nucleus center of mass. We also measured an excitation function with data points at 142, 180, 220, and 256 MeV incident pion energy at the largest achievable angle for each energy between 160 deg and 170 deg in the pi-nucleus center of mass. This excitation function corresponds to the energies of our forward-hemisphere studies. The data, taken as a whole, show an apparent role reversal of the two charge-symmetric ratios r1 and r2 in the backward hemisphere. Also, for data > 100 deg we observe a strong dependence on the four-momentum transfer squared (-t) for all of the ratios regardless of pion energy or scattering angle, and we find that the superratio R data match very well with calculations based on the forward-hemisph...
Deuteron elastic and inelastic scattering from C-12, Mg-24, and Ni-58 at 170 MeV
Baumer, C; Bassini, R; van den Berg, AM; De Frenne, D; Frekers, D; Hagemann, M; Hannen, VM; Harakeh, MN; Heyse, J; de Huu, MA; Jacobs, E; Mielke, M; Schmidt, R; Sohlbach, H; Wortche, HJ
2001-01-01
Angular distributions for elastic and inelastic deuteron scattering on C-12. Mg-24, and Ni-58 have been measured at a bombarding energy of 170 MeV. The data are analyzed in terms of the optical model. The extracted optical model parameters are compared to existing deuteron global optical potentials.
Frehner, Marcel; Schmalholz, Stefan M.; Saenger, Erik H.; Steeb, Holger
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
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
Quasi-Elastic Scattering of 16C from 12C at 47.5 MeV/Nucleon
FAN Feng-Ying; ZHENG Tao; YE Yan-Lin; JIANG Dong-Xing; HUA Hui; LI Zhi-Huan; GE Yu-Cheng; LI Xiang-Qing; LOU Jian-Ling; SHI Fan; LV Lin-Hui; CAO Zhong-Xin; NIE Peng-Xuan; LI Qi-Te; SONG Yu-Shou; LU Fei; XU Hu-Shan; HU Zheng-Guo; WANG Meng; ZHANG Xue-Ying; LI Chen; CHEN Ruo-Fu; TANG Bin; XU Zhi-Guo; YUE Ke; ZHANG Ya-Peng; ZANG Yong-Dong; ZHANG Xue-Heng; YAO Xiang-Wu; CHEN Jin-Da; TU Xiao-Lin; ZHANG Jie; WU Da-Peng; BAI Zhen
2009-01-01
Differential cross sections for the quasi-elastic scattering of 16C at 47.5 MeV/nucleon from 12C target are measured.Coupled-channels calculations are carried out and the optical potential parameters are obtained by fitting the experimental angular distribution.
Aleem, F.
1980-03-01
The most recent measurements of the angular distribution in proton-proton elastic scattering at sqrt{s}=27.4, 45 and 62GeV with squared four momentum transfer, -t, extending up to 14(GeV/c)2, have been explained using Van der Waals type model.
李凤明; 胡超; 徐敏强; 黄文虎
2003-01-01
Based on the theory of elastic dynamics, multiple scattering of elastic waves anddynamic stress concentrations in fiber-reinforced composite are studied. The analytical expressions ofelastic waves in different regions are presented. The mode coefficients of elastic waves are determinedin accordance with the continuous conditions of displacement and stress on the boundary of the multi-interfaces. By using the addition theorem of Hankel functions, the formula of scattered wave fields indifferent local coordinates are transformed into those in one local coordinate to determine the unknowncoefficients and dynamic stress concentration factors (DSCFs). The influences of the distance betweentwo inclusions, material properties and structural size on the DSCFs near the interfaces are analyzed.As examples, the numerical results of DSCFs near the interfaces for two kinds of fiber-reinforcedcomposites are presented and discussed.
Elastic Scattering of Low Energy Pions by Nuclei and the In-Medium Isovector πN Amplitude
Friedman, E.; Bauer, M.; Breitschopf, J.; Clement, H.; Denz, H.; Doroshkevich, E.; Erhardt, A.; Hofman, G. J.; Kritchman, S.; Meier, R.; Wagner, G. J.; Yaari, G.
2006-07-01
Measurements of elastic scattering of 21.5 MeV π± by Si, Ca, Ni and Zr were made using a single arm magnetic spectrometer and absolute calibration was made by parallel measurements of Coulomb scattering of muons. Optical model fits to the data reveal the `anomalous' s-wave repulsion known from pionic atoms. Introducing a chiral-motivated density dependence of the isovector scattering amplitude, and considering the energy dependence of the free πN interaction greatly improve fits to the data and remove the `anomaly'.
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.
Haibo, Xu
2014-01-01
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 benefit for reconstructing density that depends on the transmission expressions.
SCANDAL -- A facility for elastic neutron scattering studies in the 50--130 MeV range
Klug, J.; Blomgren, J.; Atac, A.; Bergenwall, B.; Dangtip, S.; Elmgren, K.; Johansson, C.; Olsson, N.; Prokofiev, A.V.; Rahm, J. [Uppsala Univ. (Sweden). Dept. of Neutron Research; Jonsson, O.; Nilsson, L.; Renberg, P.U. [Uppsala Univ. (Sweden). The Svedberg Laboratory; Nadel-Turonski, P. [Uppsala Univ. (Sweden). Dept. of Radiation Sciences; Ringbom, A. [Swedish Defence Research Establishment (FOA), Stockholm (Sweden); Oberstedt, A.; Tovesson, F. [Oerebro Univ. (Sweden). Dept. of Technology and Science; Le Brun, C.; Lecolley, J.F.; Lecolley, F.R.; Louvel, M.; Marie, N.; Schweitzer, C.; Varignon, C. [Univ. de Caen (France); Eudes, Ph.; Haddad, F.; Kerveno, M.; Kirchner, T.; Lebrun, C. [Univ. de Nantes (France); Stuttge, L. [IReS, Strasbourg (France); Slypen, I. [Univ. Catholique de Louvain (Belgium). Inst. de Physique Nucleaire; Smirnov, A.N. [V.G. Khlopin Radium Institute, St. Petersburg (Russian Federation); Michel, R.; Neumann, S. [Univ. Hannover (Germany). Zentrum fuer Strahlenschutz und Radiooekologie; Herpers, U. [Univ. Cologne (Germany). Abteilung Nuklearchemie
2001-01-01
A facility for detection of scattered neutrons in the energy interval 50--130 MeV, SCANDAL (SCAttered Nucleon Detection AssembLy), has recently been installed at the 20--180 MeV neutron beam facility of the The Svedberg Laboratory, Uppsala. It is primarily intended for studies of elastic neutron scattering, but can be used for the (n,p) and (n,d) reaction experiments as well. The performance of the spectrometer is illustrated in measurements of the (n,p) and (n,n) reactions on {sup 1}H and {sup 12}C. In addition, the neutron beam facility is described in some detail.
Quasi-elastic scattering of 6He, 7Be, and 8B nuclei by 12C nuclei
Kovalchuk, V I
2016-01-01
The observed cross sections of quasi-elastic scattering of 6He, 7Be, and 8B nuclei by 12C nuclei are described within the framework of the diffraction nuclear model and the model of nucleus-nucleus scattering in the high-energy approximation with a double folding potential, for intermediate energies of the incident particles. The calculations make use of realistic distributions of nucleon densities and take account of the Coulomb interaction and inelastic scattering with excitation of low-lying collective states of the target.
Nuclear-matter distributions of halo nuclei from elastic proton scattering in inverse kinematics
Egelhof, P.; Bauchet, A.; Fritz, S.; Geissel, H.; Gross, C.; Kraus, G.; Muenzenberg, G.; Neumaier, S.R.; Schaefer, T.; Scheidenberger, C. [Gesellschaft fuer Schwerionenforschung (GSI), D-64291 Darmstadt (Germany); Alkhazov, G.D.; Andronenko, M.N.; Gavrilov, G.E.; Khanzadeev, A.V.; Korolev, G.A.; Lobodenko, A.A.; Seliverstov, D.M.; Timofeev, N.A. [Petersburg Nuclear Physics Institute (PNPI), RU-188300 Gatchina (Russian Federation); Dobrovolsky, A.V. [Gesellschaft fuer Schwerionenforschung (GSI), D-64291 Darmstadt (Germany); Petersburg Nuclear Physics Institute (PNPI), RU-188300 Gatchina (Russian Federation); Mutterer, M. [Institut fuer Kernphysik (IKP), Technische Universitaet, D-64289 Darmstadt (Germany); Vorobyov, A.A.; Yatsoura, V.I.
2002-10-01
Proton-nucleus elastic scattering at intermediate energies, a well-established method for probing nuclear-matter density distributions of stable nuclei, was applied for the first time to exotic nuclei. This method is demonstrated to be an effective means for obtaining accurate and detailed information on the size and radial shape of halo nuclei. Absolute differential cross-sections for small-angle scattering were measured at energies near 700 MeV/u for the neutron-rich helium isotopes {sup 6}He and {sup 8}He, and more recently for the lithium isotopes {sup 6}Li, {sup 8}Li, {sup 9}Li and {sup 11}Li, using He and Li beams provided by the fragment separator FRS at GSI Darmstadt. Experiments were performed in inverse kinematics using the hydrogen-filled ionization chamber IKAR which served simultaneously as target and recoil-proton detector. For deducing nuclear-matter distributions, differential cross-sections calculated with the aid of the Glauber multiple-scattering theory, using various parametrizations for the nucleon density distributions as input, were fitted to the experimental cross-sections. The results on nuclear-matter radii and matter distributions are presented, and the significance of the data for a halo structure is discussed. Nuclear-matter distributions obtained for {sup 6}He and {sup 8}He conform with the concept that both nuclei compose of {alpha}-particle like cores and significant neutron halos. The matter distribution in {sup 11}Li exhibits, as expected from previous reaction cross-section studies with nuclear targets, the by far most extended halo component of all nuclei being investigated. In addition the present data allow a quantitative comparison of the structure of the He and Li isobars of either the mass number A=6 or A=8. The measured differential cross-sections have also been used for probing density distributions as predicted from various microscopic calculations. A few examples are presented. (orig.)
Measurement of Neutrino-Nucleon Neutral-Current Elastic Scattering Cross-section at SciBooNE
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
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...
Auger, J.-C.; Fernandes, G. E.; Aptowicz, K. B.; Pan, Y.-L.; Chang, R. K.
2010-04-01
The relation between the surface roughness of aerosol particles and the appearance of island-like features in their angle-resolved elastic-light scattering patterns is investigated both experimentally and with numerical simulation. Elastic scattering patterns of polystyrene spheres, Bacillus subtilis spores and cells, and NaCl crystals are measured and statistical properties of the island-like intensity features in their patterns are presented. The island-like features for each class of particle are found to be similar; however, principal-component analysis applied to extracted features is able to differentiate between some of the particle classes. Numerically calculated scattering patterns of Chebyshev particles and aggregates of spheres are analyzed and show qualitative agreement with experimental results.
Kiss, G G; Fülöp, Zs; Gyürky, Gy; Elekes, Z; Farkas, J; Somorjai, E; Yalcin, C; Galaviz, D; Güray, R T; Özkan, N; Görres, J
2013-01-01
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 along the $Z = 48$ isotopic and $N = 62$ isotonic chain is investigated by the study of the ratios of the of $^{106,110,116}$Cd($\\alpha,\\alpha$)$^{106,110,116}$Cd scattering cross sections at E$_{c.m.} \\approx$ 15.6 and 18.8 MeV and the ratio of the $^{110}$Cd($\\alpha,\\alpha$)$^{110}$Cd and $^{112}$Sn($\\alpha,\\alpha$)$^{112}$Sn reaction cross sections at E$_{c.m.} \\approx$ 18.8 MeV, respectively. These ratios are sensitive probes for the alpha-nucleus optical potential parameterizations. The potentials under study are a basic...
An IBEM solution to the scattering of plane SH-waves by a lined tunnel in elastic wedge space
Zhongxian Liu; Lei Liu
2015-01-01
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.
A study of quasi-elastic muon neutrino and antineutrino scattering in the NOMAD experiment
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.)
Korda, V. Yu.; Molev, A. S.; Klepikov, V. F.; Korda, L. P.
2015-02-01
Using the evolutionary model-independent S -matrix approach, we show that a simultaneous correct description of the pictures of nuclear rainbow, prerainbow, and anomalous large-angle scattering (ALAS) in the 4He-40Ca elastic scattering can be achieved with help of the S -matrix moduli and the real nuclear phases exhibiting smooth monotonic dependencies on angular momentum, while the quantum deflection functions have a form characteristic of the nuclear rainbow case. The special role of the surface partial waves in the formation of ALAS is revealed.
Furumoto, T; Yamamoto, Y
2016-01-01
We investigate the property of the high-density nuclear matter probed by the nucleus-nucleus elastic scattering in the framework of the double-folding (DF) model with the complex $G$-matrix interaction. The medium effect including three-body-force (TBF) effect is investigated with present two methods based on the frozen density approximation. With the both methods, the medium effect in the high density region is clearly seen on the potential and the elastic cross section of the $^{16}$O + $^{16}$O system at $E/A =$ 70 MeV. The crucial role of the medium effect for the high-density nuclear matter is also confirmed with other effective nucleon-nucleon ($NN$) interactions. In addition, present methods are applied to other heavy-ion elastic scattering systems. Again, the medium effect in the high-density region is clearly seen in the heavy-ion elastic cross section. The effect on the elastic cross section becomes invisible with the increase of the target mass and the incident energy within existing the experiment...
Ye, Ruichao; Petrovitch, Christopher; Pyrak-Nolte, Laura; Wilcox, Lucas
2015-01-01
We develop an approach for simulating acousto-elastic wave phenomena, including scattering from fluid-solid boundaries, where the solid is allowed to be anisotropic, with the Discontinuous Galerkin method. We use a coupled first-order elastic strain-velocity, acoustic velocity-pressure formulation, and append penalty terms based on interior boundary continuity conditions to the numerical (central) flux so that the consistency condition holds for the discretized Discontinuous Galerkin weak formulation. We incorporate the fluid-solid boundaries through these penalty terms and obtain a stable algorithm. Our approach avoids the diagonalization into polarized wave constituents such as in the approach based on solving elementwise Riemann problems.
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
Nucleon momentum distributions and elastic electron scattering form factors for some 1p-shell nuclei
A K Hamoudi; M A Hasan; A R Ridha
2012-05-01
The nucleon momentum distributions (NMD) and elastic electron scattering form factors of the ground state for 1p-shell nuclei with = (such as 6Li, 10B, 12C and 14N nuclei) have been calculated in the framework of the coherent density ﬂuctuation model (CDFM) and expressed in terms of the weight function $|f(x)|^2$. The weight function has been expressed in terms of nucleon density distribution (NDD) of the nuclei and determined from the theory and the experiment. The feature of the long-tail behaviour at high-momentum region of the NMDs has been obtained by both the theoretical and experimental weight functions. The experimental form factors $F(q)$ of all the considered nuclei are very well reproduced by the present calculations for all values of momentum transfer . It is found that the contributions of the quadrupole form factors $F_{C2}(q)$ in 10B and 14N nuclei, which are described by the undeformed p-shell model, are essential for obtaining a remarkable agreement between the theoretical and experimental form factors.
Peters, J; Martinez, N; Lehofer, B; Prassl, R
2017-07-01
Human low-density lipoprotein (LDL) is a highly complex nano-particle built up of various lipid classes and a single large protein moiety (apoB-100) owning essential physiological functions in the human body. Besides its vital role as a supplier of cholesterol and fat for peripheral tissues and cells, it is also a known key player in the formation of atherosclerosis. Due to these important roles in physiology and pathology the elucidation of structural and dynamical details is of great interest. In the current study we drew a broader picture of LDL dynamics using elastic incoherent neutron scattering (EINS) as a function of specified temperature and pressure points. We not only investigated a normolipidemic LDL sample, but also a triglyceride-rich and an oxidized one to mimic pathologic conditions as found under hyperlipidemic conditions or in atherosclerotic plaques, respectively. We could show that pressure has a significant effect on atomic motions in modified forms of LDL, whereas the normolipidemic sample seems to cope much better with high-pressure conditions irrespective of temperature. These findings might be explained by the altered lipid composition, which is either caused through elevated triglyceride content or modifications through lipid peroxidation.
Sonvico, Fabio [Dipartimento di Farmacia, Universita di Parma and INFM, Parma I-43100 (Italy); Di Bari, Maria Teresa [Dipartimento di Fisica, Universita di Parma, INFM and CNISM, Parma I-43100 (Italy); Bove, Livia [INFM-OGG and CRS-SOFT, c/o Institue Laue-Langevin, 38042 Grenoble (France); Deriu, Antonio [Dipartimento di Fisica, Universita di Parma, INFM and CNISM, Parma I-43100 (Italy)]. E-mail: Antonio.Deriu@fis.unipr.it; Cavatorta, Fabrizio [Dipartimento di Fisica, Universita di Parma, INFM and CNISM, Parma I-43100 (Italy); Albanese, Gianfranco [Dipartimento di Fisica, Universita di Parma, INFM and CNISM, Parma I-43100 (Italy)
2006-11-15
Recently, we have started a systematic study of the structure and dynamics of nano- and microparticles of interest as highly biocompatible drug carriers. For these particles, that are composed of polymeric and lipid material, a detailed understanding of the particle-solvent interactions is of key importance in order to tailor their characteristics for delivering drugs with specific chemical properties. Here we report results of elastic neutron scattering (ENS) investigations on lecithin/chitosan nanoparticles. They were first prepared by autoassembling the two components in aqueous solution; the samples were then freeze-dried and re-hydrated in a D{sub 2}O atmosphere. The experiments were performed in the temperature range of 20-50 K using the backscattering spectrometer IN13 at ILL (Grenoble, France). The comparison of samples in the dry state with similar ones at an hydration level of about 0.3-0.4 (g D{sub 2}O/g hydrated sample), indicates that the presence of an outer chitosan 'coating' reduces the mean square fluctuations of the hydrogens in the lipid component, leading thus to a stiffer nanoparticle structure.
Elastic scattering spectroscopy in vivo: optical biopsies of cancers of the breast and GI tract
Pickard, David C. O.; Briggs, Gavin M.; Saunders, Christobel; Lakhani, Sunil; Ripley, Paul M.; Bigio, Irving J.; Bown, Stephen G.
2000-04-01
Elastic scattering or diffuse reflectance spectroscopy offers the possibility of distinguishing between normal and neoplastic tissue with a relatively simple optical measurement. The measurement of the reflection of light has previously been shown to be sensitive to the size and distribution of both intra and inter-cellular structures as well as absorption from chromatophores which are present in the tissue. By coupling a white light source and spectrometer to optic fibers it is possible to construct probes which can be inserted precutaneously or intra- operatively into breast tissue or which can pass down the channel of an endoscope and take in-vivo spectra of diseased and normal tissue in the Gastro-Intestinal tract. Spectra are reported from a large number of patients with a variety of benign, metaplastic, dysplastic and cancerous conditions. Some differences that have been observed in these spectra are discussed and the merits and disadvantages of 'optical biopsy' as an in-vivo diagnostic tool are examined. It is shown that to a relatively high degree of sensitivity and specificity it is possible to distinguish cancerous from normal tissue in a number of cases. The methods of distinguishing spectra and some possible modalities for their improvement are discussed.
Time-frequency analysis of the bistatic acoustic scattering from a spherical elastic shell.
Anderson, Shaun D; Sabra, Karim G; Zakharia, Manell E; Sessarego, Jean-Pierre
2012-01-01
The development of low-frequency sonar systems, using, for instance, a network of autonomous systems in unmanned vehicles, provides a practical means for bistatic measurements (i.e., when the source and receiver are widely separated) allowing for multiple viewpoints of the target of interest. Time-frequency analysis, in particular, Wigner-Ville analysis, takes advantage of the evolution time dependent aspect of the echo spectrum to differentiate a man-made target, such as an elastic spherical shell, from a natural object of the similar shape. A key energetic feature of fluid-loaded and thin spherical shell is the coincidence pattern, also referred to as the mid-frequency enhancement (MFE), that results from antisymmetric Lamb-waves propagating around the circumference of the shell. This article investigates numerically the bistatic variations of the MFE with respect to the monostatic configuration using the Wigner-Ville analysis. The observed time-frequency shifts of the MFE are modeled using a previously derived quantitative ray theory by Zhang et al. [J. Acoust. Soc. Am. 91, 1862-1874 (1993)] for spherical shell's scattering. Additionally, the advantage of an optimal array beamformer, based on joint time delays and frequency shifts is illustrated for enhancing the detection of the MFE recorded across a bistatic receiver array when compared to a conventional time-delay beamformer.
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.
Sobków, W
2015-01-01
In this paper, we show how a presence of the exotic scalar, tensor weak interactions in addition to the standard vector-axial (V-A) one may help to distinguish the Dirac from Majorana neutrinos in the elastic scattering of (anti)neutrino beam off the unpolarized electrons in the limit of vanishing (anti)neutrino mass. We assume that the incoming (anti)neutrino beam comes from the polarized muon decay at rest and is the left-right chiral mixture with assigned direction of the transversal spin polarization with respect to the production plane. We display that the azimuthal asymmetry in the angular distribution of recoil electrons is generated by the interference terms between the standard and exotic couplings, which are proportional to the transversal (anti)neutrino spin polarization and independent of the neutrino mass. This asymmetry for the Majorana neutrinos is distinct from the one for the Dirac neutrinos through the absence of interference between the standard and tensor couplings. Additionally, the inter...
Structure of 8B from elastic and inelastic 7Be+p scattering
Mitchell, J P; Johnson, E D; Baby, L T; Kemper, K W; Moro, A M; Peplowski, P; Volya, A S; Wiedenhoever, I
2013-01-01
Motivation: Detailed experimental knowledge of the level structure of light weakly bound nuclei is necessary to guide the development of new theoretical approaches that combine nuclear structure with reaction dynamics. Purpose: The resonant structure of 8B is studied in this work. Method: Excitation functions for elastic and inelastic 7Be+p scattering were measured using a 7Be rare isotope beam. Excitation energies ranging between 1.6 and 3.4 MeV were investigated. An R-matrix analysis of the excitation functions was performed. Results: New low-lying resonances at 1.9, 2.5, and 3.3 MeV in 8B are reported with spin-parity assignment 0+, 2+, and 1+, respectively. Comparison to the Time Dependent Continuum Shell (TDCSM) model and ab initio no-core shell model/resonating-group method (NCSM/RGM) calculations is performed. This work is a more detailed analysis of the data first published as a Rapid Communication. [J.P. Mitchell, et al, Phys. Rev. C 82, 011601(R) (2010)] Conclusions: Identification of the 0+, 2+, 1+...
15O+α resonant elastic scattering to study cluster states in19Ne
Torresi, D.; Wheldon, C.; Kokalova, Tz; Bailey, S.; Boiano, A.; Boiano, C.; Cavallaro, M.; Cherubini, S.; Di Pietro, A.; Fernandez Garcia, J. P.; Fisichella, M.; Glodariu, T. R.; Grebosz, J.; La Cognata, M.; La Commara, M.; Lattuada, M.; Mazzocco, M.; Mengoni, D.; Parascandolo, C.; Pierroutsakou, D.; Pizzone, G.; Signorini, C.; Stefanini, C.; Stroe, L.; Spitaleri, C.; Strano, E.; Zadro, M.
2017-06-01
Clustering phenomena are well known in nuclear physics for stable nuclei, both α-conjugate (N=Z, A=2N), like8Be,16O,20Ne, and non-α-conjugate, like6Li and7Li. In general, it is expected that light exotic nuclei may also exhibit cluster behavior. Moving out of the valley of stability configurations can be found where at least one of the clusters is unbound or weakly bound, thus not satisfying the strong internal correlation requirement of classical clusters. This is so-called exotic clustering. The study of such systems presents many difficulties, due, mainly, to the low intensities typical of radioactive ion beams. Therefore, few significant experimental studies have been performed so far. In this work we searched for α-cluster states in19Ne above its α-decay threshold measuring, for the first time, the15O(4He,4He) elastic scattering excitation function. Moreover, this study classified low-energy states in Ne in the astrophysically important region in this HCNO-break-out nucleus.
Neutron Densities from a Global Analysis of Medium Energy Proton Nucleus Elastic Scattering
Clark, B C; Kerr, L J
2003-01-01
A new method for extracting neutron densities from intermediate energy elastic proton-nucleus scattering observables uses a global Dirac phenomenological (DP) approach based on the Relativistic Impulse Approximation (RIA). Data sets for Ca40, Ca48 and Pb208 in the energy range from 500 MeV to 1040 MeV are considered. The global fits are successful in reproducing the data and in predicting data sets not included in the analysis. Using this global approach, energy independent neutron densities are obtained. The vector point proton density distribution is determined from the empirical charge density after unfolding the proton form factor. The other densities are parametrized. The RMS neutron radius, R_n and the neutron skin thickness S_n obtained from the global fits using the most conservative errors are given as follows: for Ca40 R_n is (3.325 +/- 0.025) fm and S_n (-0.044 +/- 0.036) fm; for Ca48 R_n is (3.463 +/- 0.042) fm and S_n (0.103 +/- 0.045) fm; and for Pb208 R_n is (5.551 +/- 0.038) and S_n (0.116 +/-...
Dolmatov, V K; Chernysheva, L V
2016-01-01
A deeper insight into electron elastic scattering off endohedral fullerenes $A$@C$_{60}$ is provided. The study accounts for polarization of both the encapsulated atom $A$ and C$_{60}$ cage by an incident electron. It is carried out in the framework of the combination of both a model and the first-principle approximations. A core principle of the model is that the C$_{60}$ cage itself is presented by an attractive spherical potential of a certain inner radius, thickness, and depth. The main idea of the first-principle approximation is that the polarization of $A$@C$_{60}$ by an incident electron is accounted with the help of the Dyson equation for the self-energy part of the Green's function of an incident electron. Calculations are performed for, and comparison is made between the individual cases: (a) when $A$@C$_{60}$ is regarded as a static system, (b) when C$_{60}$ is a static cage, but the encapsulated atom is polarizable, (c) when both C$_{60}$ and $A$ are polarized simultaneously but independently of ...
Elasticity of the eye's crystalline lens: A Brillouin light scattering study.
Bailey, S.; Gump, J.; Sooryakumar, R.; Jayaprakash, C.; Venkiteshwar, M. S.; Bullimore, M.; Twa, M.
2009-03-01
Focusing the eye on a near object results in an increase in its optical power brought about by contraction of the ciliary muscles and an increase in the lens surface curvature. Distant vision occurs when the muscular force flattens the lens. Central to the ability of the lens to alter shape are its mechanical properties. Thus, given that hardening of the lens would impede deformation and reduce its ability to undergo the changes required for accommodation, a noninvasive approach to measure the elastic properties of the lens is valuable. We present results of Brillouin scattering from bovine and human lenses (from the organ donor program at The Ohio State University) that measure their high frequency acoustic response. These measurements are conducted with a few milli-watts of laser power and, in the case of bovine lenses, from entire intact eye globes, allow the stiffness of the lens to be mapped across its cross-section. The results will be compared to values of the shear- and bulk-moduli determined from other techniques and the implications of differences in these moduli discussed.
Anti-Neutrino Charged Current Quasi-Elastic Scattering in MINER$\
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
Wuttke, Joachim
2012-10-01
In a recent contribution to this journal, Magazù, Migliardo, and Benedetto suggest to determine relaxation times from inflection points in the elastic neutron scattering intensity as function of (1) resolution time or (2) temperature. Method (1) can be generalized into a scaling law. Method (2) is only approximately valid; its application to protein data does not back a wavenumber-independent dynamic transition.
Lysenko, Sergiy; Fernández, Felix; Rúa, Armando; Sepúlveda, Nelson; Aparicio, Joaquin
2015-03-10
Measurements of ultrafast light scattering within a hemisphere are performed for statistical analysis of nonequilibrium processes in VO2 epitaxial film. A Gerchberg-Saxton error reduction algorithm is applied for accurate calculation of a surface autocorrelation function from light scattering data and for partial reconstruction of a power spectral density function. Upon ultrafast photoinduced phase transition of VO2, the elastic light scattering reveals anisotropic grain-size-dependent dynamics. It was found that the transition rate depends on the optical absorption and orientation of VO2 grains with respect to polarization of the pump pulse. An observed stepwise evolution of surface autocorrelation length and transient anisotropy of the scattering field presumably originates from complex multistage transformation of VO2 lattice on a subpicosecond time scale.
Nuclear effects on ion heating within the small-angle charged-particle elastic-scattering regime
Andrade, A.; Hale, G. M.
1984-10-01
The effects of nuclear forces (in contrast to pure Coulomb interaction) on the ion heating rate which results from small-angle scattering processes between charged particles in plasmas are investigated within the framework of Fokker-Planck theory. These effects are included through the addition of analytic Coulomb-nuclear interference and nuclear elastic cross sections in the scattering integrals of the dynamical friction coefficient and dispersion tensor. It is found that corrections to traditional Fokker-Planck predictions of the ion-ion energy exchange rate can be calculated and that these corrections are sensitive to the choice of the maximum scattering angle defining the cutoff between small- and large-angle scattering.
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.
Elastic scattering of low energy pions by nuclei and the in-medium isovector pi N amplitude
Friedman, E; Bauer, M.; Breitschopf, J.; H. Clement; Denz, H; Doroshkevich, E.; Erhardt, A.; Hofman, G. J.; Kritchman, S.; Meier, R.; Wagner, G. J.; Yaari, G
2005-01-01
Measurements of elastic scattering of 21.5 MeV pi+ and pi- by Si, Ca, Ni and Zr were made using a single arm magnetic spectrometer. Absolute calibration was made by parallel measurements of Coulomb scattering of muons. Parameters of a pion-nucleus optical potential were obtained from fits to all eight angular distributions put together. The `anomalous' s-wave repulsion known from pionic atoms is clearly observed and could be removed by introducing a chiral-motivated density dependence of the ...
Reactivity impact of 2H and 16O elastic scattering nuclear data on critical systems with heavy water
Roubtsov, D.; KOZIER K.; Chow, J. C.; Plompen, Arjan; Kopecky, Stefan; Svenne, J. P.; Canton, L.
2013-01-01
The accuracy of deuterium nuclear data is important for reactor physics simulations of heavy water (D2O) reactors. The elastic neutron scattering cross section data at thermal energies, σs, th, have been observed to have noticeable impact on the reactivity values in simulations of critical systems involving D2O. We discuss how the uncertainties in the thermal scattering cross sections of 2H(n,n)2H and 16O(n,n)16O propagate to the uncertainty of the calculated neutron multiplication factor, ke...
Amador-Valenzuela, P.; Aguilera, E. F.; Martinez-Quiroz, E.; Lizcano, D.; Morales-Rivera, J. C.
2017-07-01
Recently, experimental measurements of elastic scattering angular distributions for the system7Li+58Ni at ten different energies around the Coulomb barrier were made by the Heavy-Ion Group. The measurements were made at the Tandem Van de Graaff Particle Accelerator Laboratory in the National Institute for Nuclear Research (ININ) in Mexico. In this work, preliminary elastic scattering angular distributions for five energies (E lab , = 12.0, 12.5, 13.0, 13.5 and 14.22 MeV) are presented. The preliminary experimental data were analyzed using the São Paulo Optical Model Potential (SPP) which is based on a double-folding potential, reproducing very well these data. A comparison is made with old data reported back in 1973 and in 2012. Further analysis is in progress in order to fully understand this particular system, specially because7Li is known to be a weakly bound nucleus.
Analyzing power in elastic scattering of 6He from polarized proton target at 71 MeV/nucleon
Sakaguchi, S; Uesaka, T; Tanifuji, M; Amos, K; Aoi, N; Hashimoto, Y; Hiyama, E; Ichikawa, M; Ichikawa, Y; Ishikawa, S; Itoh, K; Itoh, M; Iwasaki, H; Karataglidis, S; Kawabata, T; Kawahara, T; Kuboki, H; Maeda, Y; Matsuo, R; Nakao, T; Okamura, H; Sakai, H; Sasamoto, Y; Sasano, M; Satou, Y; Sekiguchi, K; Shinohara, M; Suda, K; Suzuki, D; Takahashi, Y; Tamii, A; Wakui, T; Yako, K; Yamaguchi, M; Yamamoto, Y
2011-01-01
The vector analyzing power has been measured for the elastic scattering of neutron-rich 6He from polarized protons at 71 MeV/nucleon making use of a newly constructed solid polarized proton target operated in a low magnetic field and at high temperature. Two approaches based on local one-body potentials were applied to investigate the spin-orbit interaction between a proton and a 6He nucleus. An optical model analysis revealed that the spin-orbit potential for 6He is characterized by a shallow and long-ranged shape compared with the global systematics of stable nuclei. A semimicroscopic analysis with a alpha+n+n cluster folding model suggests that the interaction between a proton and the alpha core is essentially important in describing the p+6He elastic scattering. The data are also compared with fully microscopic analyses using non-local optical potentials based on nucleon-nucleon g-matrices.
TAN Jia-Jin; LU Juan; CHENG Yan; ZHOU Li-Huan; ZHU Wen-Jun; MA Wei-Xing; GOU Qing-Quan
2008-01-01
Based on the quark-gluon structure of nucleon and the existence of Odderon in nucleon via gluon self-interaction, the elastic scattering of pp at high energies is studied. Our theoretical predictions reproduce experimental data perfectly. The contributions from individual terms of quark-quark, gluon-gluon interactions, quark-gluon interfer-ence and the Odderon terms to total cross section are analyzed. In addition to the leading quark-quark contribution, the Odderon contribution is quite important. In particular, the Odderon plays an essential role in fitting to data. Therefore, We may claim that the high energy lap and pp elastic scattering may be good processes to search for the Odderon, the three Reggeized gluon bound states.
He Xiao-Kang; Zeng Li-Bo; Wu Qiong-Shui; Zhang Li-Yan; Zhu Ke; Liu Yu-Long
2012-01-01
From the sound velocity measured using the Brillouin scattering technique,the elastic,piezoelectric,and dielectric constants of a high-quality monodomain tetragonal Rh:BaTiO3 single crystal are determined at room temperature.The elastic constants are in fairly good agreement with those of the BaTiO3 single crystal,measured previously by Brillouin scattering and the low-frequency equivalent circuit methods.However,their electromechanical properties are significantly different.Based on the sound propagation equations and these results,the directional dependence of the compressional modulus and the shear modulus of Rh:BaTiO3 in the (010) plane is investigated.Some properties of sound propagation and electromechanical coupling in the crystal are discussed.
Cross sections for elastic scattering of electrons by CF3Cl, CF2Cl2, and CFCl3.
Hoshino, M; Horie, M; Kato, H; Blanco, F; García, G; Limão-Vieira, P; Sullivan, J P; Brunger, M J; Tanaka, H
2013-06-07
Differential, integral, and momentum transfer cross sections have been determined for the elastic scattering of electrons from the molecules CF3Cl, CF2Cl2, and CFCl3.With the help of a crossed electron beam-molecular beam apparatus using the relative flow technique, the ratios of the elastic differential cross sections (DCSs) of CF3Cl, CF2Cl2, and CFCl3 to those of He were measured in the energy region from 1.5 to 100 eV and at scattering angles in the range 15° to 130°. From those ratios, the absolute DCSs were determined by utilizing the known DCS of He. For CF3Cl and CF2Cl2, at the common energies of measurement, we find generally good agreement with the results from the independent experiments of Mann and Linder [J. Phys. B 25, 1621 (1992); and ibid. 25, 1633 (1992)]. In addition, as a result of progressively substituting a Cl-atom, undulations in the angular distributions have been found to vary in a largely systematic manner in going from CF4 to CF3Cl to CF2Cl2 to CFCl3 and to CCl4. These observed features suggest that the elastic scattering process is, in an independently additive manner, dominated by the atomic-Cl atoms of the molecules. The present independent atom method calculation typically supports the experimental evidence, within the screened additivity rule formulation, for each species and for energies greater than about 10-20 eV. Integral elastic and momentum transfer cross sections were also derived from the measured DCSs, and are compared to the other available theoretical and experimental results. The elastic integral cross sections are also evaluated as a part of their contribution to the total cross section.
Measurement of the Cross Section and Analyzing Powers for d+p Elastic Scattering at 180 MeV
Bailey, C. D.; Stephenson, E. J.; Bacher, A. D.; Micherdzinska, A. M.; Messchendorp, J. G.; Biegun, A.; Eslami-Kalantari, M.; Joulaeizadeh, L.; Kalantar-Nayestanaki, N.; Mardanpour, H.; Moeini, H.; Ramazani-Moghaddam-Arani, A.; Shende, S. V.; Wörtche, H.; Stephan, E.; Kistryn, St.; Sekiguchi, K.
2008-04-01
We have measured cross sections and analyzing powers for various d+d reaction channels, including d+d elastic and d+d->p+t at 130 MeV and 180 MeV, with the hope of providing a testing ground for new 4-body theoretical predictions. These data were collected at the KVI cyclotron (Groningen) using the Big Bite spectrometer and a polarized deuteron beam. In addition to the d+d channels, we also measured the cross section and analyzing powers (Ay and Ayy) for d+p elastic scattering at the same energies for comparison with existing data and with 3-body calculations (with and without three nucleon forces). We report here our results for the d+p elastic data at 180 MeV. The analysis procedure will be reviewed and several preliminary results will be shown.
Scattering of flexural--gravity waves by a group of elastic plates floating on a stratified fluid
Meng, Q R
2016-01-01
A hydroelastic problem of flexural--gravity wave scattering by the demarcation between two floating elastic plates is investigated within the frame of linear potential theory, where the method of matched eigenfunction expansions is employed for analysis. A generalised extension is subsequently derived to promote the formulations to the case of multiple elastic plates on a stratified fluid with multiple layers, which is helpful to study the hydrodynamic behaviours of inhomogeneous floating covers as well as the effects of density stratification in seawater. The eigenfunction expansions are numerically calculated by an inner product technique, in which an orthogonal definition proposed with an explicit differential term exhibits the effectiveness for a multiple layer fluid in dealing with the matching relations between adjacent regions covered by different elastic plates. By use of Green's theorem, an energy conversation relation is deduced to assure the convergence of the calculation to the physical reality, a...
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.
Measurement of the vector and tensor analyzing powers for dp- elastic scattering at 880 MeV
Kurilkin, P K; Uesaka, T; Suda, K; Gurchin, Yu V; Isupov, A Yu; Itoh, K; Janek, M; Karachuk, J -T; Kawabata, T; Khrenov, A N; Kiselev, A S; Kizka, V A; Krasnov, V A; Ladygina, N B; Livanov, A N; Maeda, Y; Malakhov, A I; Piyadin, S M; Reznikov, S G; Sakaguchi, S; Sakai, H; Sasamoto, Y; Sekiguchi, K; Shikhalev, M A; Vasiliev, T A; Witala, H
2012-01-01
The vector Ay and tensor analyzing powers Ayy and Axx for dp- elastic scattering were measured at Td = 880 MeV over the c.m. angular range from 60 to 140 degrees 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.
Study of the elastic scattering of 6He on 208Pb at energies around the Coulomb barrier
Sanchez-Benitez, A M; Escrig, D.; Alvarez, M. A.; Andres, M. V.; Angulo, Carmen; Borge, M. J. G.; J. Cabrera; Cherubini, F.; Demaret, P; Espino, J. M.; Figuera, P.; Freer, Martin; Garcia-Ramos, J. E.; Gomez-Camacho, J.; Gulino, M.
2008-01-01
The elastic scattering of 6He on 208Pb 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 po- tential was used to study the e ect 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 b...
Elastic scattering of the halo nucleus {sup 6}He from {sup 208}Pb above the Coulomb barrier
Kakuee, O.R.; Rahighi, J.; Sanchez-Benitez, A.M.; Andres, M.V.; Cherubini, S.; Davinson, T.; Galster, W.; Gomez-Camacho, J. E-mail: gomez@nucle.us.es; Laird, A.M.; Lamehi-Rachti, M.; Martel, I.; Shotter, A.C.; Smith, W.B.; Vervier, J.; Woods, P.J
2003-12-15
Elastic scattering of {sup 6}He at E{sub lab}=27 MeV with {sup 208}Pb has been measured in the angular range of 6 deg.-72 deg.in the laboratory system employing LEDA and LAMP detection systems. Optical Model calculations have been performed using dynamic polarisation potential. The role of Coulomb dipole polarizability has been investigated. Large values of the imaginary diffuseness parameter are required in order to fit the data.
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
Van der Waals Type Model and Structure in bar{p}p Elastic Scattering at High Energies
Aleem, F.
1983-10-01
The most recent measurements of the angular distribution for bar{p}p elastic scattering at pL=50, 100 and 200 GeV/ c which show a structure near -t=1.4 (GeV/ c)2, with squared four momentum transter -t extended to 5(GeV/ c)2, and the total cross section data for 50 <= pL <= 280GeV/ c have been simultaneously fitted by using the Van der Waals type model.
Ratio of Real to Imaginary for pp and (p)p Elastic Scatterings in QCD Inspired Model
LU Juan; MA Wei-Xing; HE Xiao-Rong
2007-01-01
We use the QCD inspired model to analyze the ratio of the real to the imaginary for pp and 5p elastic scatterings. A calculation for the ratio of the real to the imaginary is performed in which the contributions from gluongluon interaction, quark-quark interaction, quark-gluon interaction, and odd eikonal profile function are included. Our results show that the QCD inspired model gives a good fit to the LHC experimental data.
Gómez Camacho, A.
2016-07-01
CDCC calculations of elastic scattering angular distributions for reactions of the weakly bound projectile 6Li with targets 28Si and 58Ni at energies around the Coulomb barrier are presented. Special emphasis is given to account for the effect of couplings from 6Li resonance states l = 2, J π = 3+, 2+, 1+. Similarly, the effect produced by non-resonant state couplings is studied. The convergent calculations are carried out with global α-target and d-target interactions. The calculated elastic scattering angular distributions are in general in good agreement with the measurements for the systems considered in this work. It is found that the calculations with only resonance states are very similar to that with all couplings (resonance+non-resonance). So, the absence of these states have a strong effect on elastic scattering (non-resonance states calculation). It is shown that the effects increase as the collision energy increases. An interpretation of the strength of the different effects is given in terms of the polarization potentials that emerge from the different couplings.
Gakh, G.I.; Tomasi-Gustafsson, E
2006-07-01
The general spin structure of the matrix element, taking into account the 2-photon exchange contribution, for the elastic electron (positron) - deuteron scattering has been derived using general symmetry properties of the hadron electromagnetic interaction, such as P-, C- and T-invariances as well as lepton helicity conservation in QED at high energy. Taking into account also crossing symmetry, the amplitudes of e{sup {+-}}d scattering can be parametrized in terms of fifteen real functions. The expressions for the differential cross section and for all polarization observables are given in terms of these functions. We consider the case of an arbitrary polarized deuteron target and polarized electron beam (both longitudinal and transverse). The transverse polarization of the electron beam induces a single-spin asymmetry which is non-zero in presence of 2-photon exchange. It is shown that elastic deuteron electromagnetic form factors can still be extracted in presence of 2 photon exchange, from the measurements of the differential cross sections and of one polarization observable (for example, the tensor asymmetry) for electron and positron deuteron elastic scattering, in the same kinematical conditions. (authors)
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...
Structure of 20Ne states in resonance 16O+α elastic scattering
Nauruzbayev, D. K.; Goldberg, V. Z.; Nurmukhanbetova, A. K.; Golovkov, M. S.; Volya, A.; Rogachev, G. V.; Tribble, R. E.
2017-07-01
Background: The nuclear structure of the cluster bands in 20Ne presents a challenge for many theoretical approaches. It is especially difficult to explain the broad 0+ and 2+ states, both at around 9 MeV excitation energy. More reliable experimental data for these levels is important for proper quantitative assessment and development of theoretical methods. Purpose: To obtain new data on the 20Ne α -cluster structure. Method: The thick target inverse kinematics (TTIK) technique was used to study 16O+α resonance elastic scattering and the data were analyzed using an R-matrix approach. The 20Ne spectrum and the cluster and nucleon spectroscopic factors were calculated using the cluster-nucleon configuration interaction model (CNCIM). Results: We determined the parameters of the broad resonances in 20Ne: 0+ level at 8.77 ±0.150 MeV with a width of 750-220+500 keV; 2+ level at 8.75 ±0.100 MeV with the width of 695 ±120 keV; the width of 9.48 MeV level of 65 ±20 keV; and we showed that the 9.19 MeV, 2+ level (if it exists) should have a width of ≤10 keV. A detailed comparison of the theoretical CNCIM predictions with the experimental data on cluster states was made. Conclusions: Our experimental results obtained by the TTIK method generally confirm the adopted data on α -cluster levels in 20Ne. The CNCIM gives a good description of the 20Ne positive-parity states up to an excitation energy of ˜7 MeV, predicting reasonably well the excitation energy of the states and their cluster and single-particle properties. At higher excitations, a qualitative disagreement with the experimentally observed structure is evident, especially for broad resonances.
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
An experiment of X-ray photon–photon elastic scattering with a Laue-case beam collider
T. Yamaji
2016-12-01
Full Text Available We report a search for photon–photon elastic scattering in vacuum in the X-ray region at an energy in the center of mass system of ωcms=6.5keV for which the QED cross section is σQED=2.5×10−47m2. An X-ray beam provided by the SACLA X-ray Free Electron Laser is split and the two beamlets are made to collide at right angle, with a total integrated luminosity of (1.24±0.08×1028m−2. No signal X rays from the elastic scattering that satisfy the correlation between energy and scattering angle were detected. We obtain a 95% C.L. upper limit for the scattering cross section of 1.9×10−27m2 at ωcms=6.5keV. The upper limit is the lowest upper limit obtained so far by keV experiments.
Elastic pp-scattering at s=7TeV with the genuine Orear regime and the dip
Dremin, I. M.; Nechitailo, V. A.
2012-04-01
The unitarity condition unambiguously requires the Orear region to appear in between the diffraction cone at low transferred momenta and the hard parton scattering regime at high transferred momenta in hadron elastic scattering. It originates from rescattering of the diffraction cone processes. It is shown that such a region has been observed in the differential cross-section of the elastic pp-scattering at s=7TeV. The Orear region is described by exponential decrease with the scattering angle, and imposed on it damped oscillations. They explain the steepening at the end of the diffraction cone as well as the dip and the subsequent maximum observed in TOTEM data. The failure of several models to describe the data in this region can be understood as an improper account of the unitarity condition. It is shown that the real part of the amplitude can be as large as the imaginary part in this region. The overlap function is calculated and shown to be small outside the diffraction peak. Its negative sign there indicates the important role of phases in the amplitudes of inelastic processes.
Elastic pp-scattering at \\sqrt s=7 TeV with the genuine Orear regime and the dip
Dremin, I M
2012-01-01
The unitarity condition unambigously requires the Orear region to appear in between the diffraction cone at low transferred momenta and hard parton scattering regime at high transferred momenta in hadron elastic scattering. It originates from rescattering of the diffraction cone processes. It is shown that such region has been observed in the differential cross section of the elastic pp-scattering at \\sqrt s=7 TeV. The Orear region is described by exponential decrease with the scattering angle and imposed on it damped oscillations. They explain the steepening at the end of the diffraction cone as well as the dip and the subsequent maximum observed in TOTEM data. The failure of several models to describe the data in this region can be understood as improper account of the unitarity condition. It is shown that the real part of the amplitude can be as large as the imaginary part in this region. The overlap function is calculated and shown to be small outside the diffraction peak. Its negative sign there indicate...
Measurement of Neutrino-Nucleon Neutral Current Elastic Scattering in MiniBooNE
Perevalov, Denis
2009-01-01
Using a high-statistics sample of neutral current elastic neutrino interactions, MiniBooNE measured the flux-averaged neutral current elastic differential cross-section on mineral oil ($CH_2$). Using the latter, a $\\chi^2$ test of MC with different values of the axial vector mass has been performed. Also, a possibility of using a sample of neutral current elastic proton-enriched events above Cherenkov threshold to measure the ratio $\
Elastic scattering of low energy pions by nuclei and the in-medium isovector pi N amplitude
Friedman, E; Breitschopf, J; Clement, H; Denz, H; Doroshkevich, E; Erhardt, A; Hofman, G J; Kritchman, S; Meier, R; Wagner, G J; Yaari, G
2005-01-01
Measurements of elastic scattering of 21.5 MeV pi+ and pi- by Si, Ca, Ni and Zr were made using a single arm magnetic spectrometer. Absolute calibration was made by parallel measurements of Coulomb scattering of muons. Parameters of a pion-nucleus optical potential were obtained from fits to all eight angular distributions put together. The `anomalous' s-wave repulsion known from pionic atoms is clearly observed and could be removed by introducing a chiral-motivated density dependence of the isovector scattering amplitude, which also greatly improved the fits to the data. The empirical energy dependence of the isoscalar amplitude also improves the fits to the data but, contrary to what is found with pionic atoms, on its own is incapable of removing the anomaly.
Ding, M.; Hjelm, R.; Sussman, A. J.
2016-12-01
Low-permeability geomedia are prevalent in subsurface environments. They have become increasingly important in a wide range of applications such as CO2-sequestration, hydrocarbon recovery, enhanced geothermal systems, legacy waste stewardship, high-level radioactive waste disposal, and global security. The flow and transport characteristics of low-permeability geomedia are dictated by their exceedingly low permeability values ranging from 10-6 to 10-12 darcy with porosities dominated by nanoscale pores. Developing new characterization methods and robust computational models that allow estimation of transport properties of low-permeability geomedia has been identified as a critical basic research and technology development need for controlling subsurface and fluids flow. Due to its sensibility to hydrogen and flexible sample environment, neutron based elastic and inelastic scattering can, through various techniques, interrogate all the nanoscale pores in the sample whether they are fluid accessible or not, and readily characterize interfacial waters. In this presentation, we will present two studies revealing the effects of nanoscale pore confinement on fluid dynamics in geomedia. In one study, we use combined (ultra-small)/small-angle elastic neutron scatterings to probe nanoporous features responses in geological materials to transport processes. In the other study, incoherent inelastic neutron scattering was used to distingwish between intergranular pore water and fluid inclusion moisture in bedded rock salt, and to explore their thermal stablibility. Our work demonstrates that neutron based elastic and inelastic scatterings are techniques of choice for in situ probing hydrocarbon and water behavior in nanoporous materials, providing new insights into water-rock interaction and fluids transport in low-permeability geomaterials.
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 ...
Effect of coupling in the 28Si+154Sm reaction studied by quasi-elastic scattering
Kaur, Gurpreet; Behera, B. R.; Jhingan, A.; Nayak, B. K.; Dubey, R.; Sharma, Priya; Thakur, Meenu; Mahajan, Ruchi; Saneesh, N.; Banerjee, Tathagata; Khushboo, Kumar, A.; Mandal, S.; Saxena, A.; Sugathan, P.; Rowley, N.
2016-09-01
The study of the coupling to collective states of the 28Si projectile and 154Sm target in fusion mechanism is reported. Understanding such couplings is important as they influence the barrier height and the formation probability of the compound nuclei, which in turn may be related to the synthesis of superheavy elements in heavier systems. In the present work, before performing the coupled-channel calculations, we wish to obtain an experimental signature of coupling to projectile and target excitation through barrier distribution (BD) study. To this end, the BDs of the 28Si+154Sm and 16O+154Sm systems have been compared using existing fusion data, scaled to compensate for the differences between the nominal Coulomb barriers and the respective coupling strengths. However, the large error bars on the high-energy side of the fusion BD prevent any definite identification of such signatures. We have, therefore, performed a quasi-elastic (QE) scattering experiment for the heavier 28Si+154Sm system and compared its results with existing QE data for the 16O projectile. Since QE BDs are precise at higher energies, the comparison has shown that the BD of 28Si+154Sm is similar to that of 16O+154Sm to a large extent except for a peaklike structure on the higher energy side. The similarity shows that the 154Sm deformation plays a major role in the fusion mechanism of 28Si+154Sm system. The peaklike structure is attributed to 28Si excitation. In contrast with previous studies, it is found that a coupled-channel calculation with vibrational coupling to the first 2+ state of 28Si reproduces this structure rather well. However, an almost identical result is found with the rotational coupling scheme if one considers the large positive hexadecapole deformation of the projectile. A value around that given by Möller and Nix (β4≈0.25 ) leads to a strong cancellation in the re-orientation term that couples the 2+ state back to itself, making that state look vibrational in this
Laser diagnostics in combustion. Elastic scattering and picosecond laser-induced fluorescence
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
Laser diagnostics in combustion: Elastic scattering and picosecond laser-induced fluorescence
Ossler, Frederik E.
Elastic scattering and the Lorenz-Mie (LM) theory in particular is used for the characterization of submicron- 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 0.01 and 10
Reactivity Impact of 2H and 16O Elastic Scattering Nuclear Data on Critical Systems with Heavy Water
Roubtsov, D.; Kozier, K. S.; Chow, J. C.; Plompen, A. J. M.; Kopecky, S.; Svenne, J. P.; Canton, L.
2014-04-01
The accuracy of deuterium nuclear data is important for reactor physics simulations of heavy water (D2O) reactors. The elastic neutron scattering cross section data at thermal energies, σs,th, have been observed to have noticeable impact on the reactivity values in simulations of critical systems involving D2O. We discuss how the uncertainties in the thermal scattering cross sections of 2H(n,n)2H and 16O(n,n)16O propagate to the uncertainty of the calculated neutron multiplication factor, keff, in thermal critical assemblies with heavy water neutron moderator/reflector. The method of trial evaluated nuclear data files, in which specific cross sections are individually perturbed, is used to calculate the sensitivity coefficients of keff to the microscopic nuclear data, such as σs(E) characterized by σs,th. Large reactivity differences of up to ≃ 5-10 mk (500-1000 pcm) were observed using 2H and 16O data files with different elastic scattering data in MCNP5 simulations of the LANL HEU heavy-water solution thermal critical experiments included in the ICSBEP handbook.
Makhoute, A.; Agueny, H.; Dubois, A.; Ajana, I.; Taoutioui, A.
2016-04-01
We report a detailed analysis of electron-helium scattering in the presence of a laser field; focusing on the elastic process of helium atoms from the ground state 11 S. The process under investigation is dealt with a nonperturbative approach using the Volkov wave function to describe the incident and scattered electrons, while the laser-target interaction is treated by using the Floquet method. The interaction of the incident electron with the atomic target is treated within the first Born approximation. Our results are perfectly consistent with the experimental data of DeHarak et al and with the Kroll-Watson approximation results for both one and two photon emission. We have investigated the effect of nonresonant and near resonant laser field on the electron-helium elastic collision process. It was found that the differential cross section is sensitive to the intensity and the frequency of the laser field. In the case of a non resonant laser field, dressing effects are important at small scattering angles. For a near-resonant laser photon energy, those effects are strongly reduced in the forward direction.
Large-angle elastic scattering of 88.03-keV photons by elements with 30{<=}Z{<=}92
Kumar, Ajay; Shahi, J.S.; Garg, M.L.; Puri, Sanjiv; Mehta, D.; Singh, Nirmal E-mail: nsingh@panjabuniv.chd.nic.in
2001-10-01
Elastic-scattering differential cross-sections for 88.03-keV photons have been measured at an angle of 125 deg. for 17 elements in the atomic region 30{<=}Z{<=}92. The measured elastic-scattering cross-sections have been compared with those obtained in the independent-particle approximation through calculations of the modified-relativistic form factors (MFs), a combination of the MFs and angle-independent 'anomalous' scattering factors (ASFs), and the relativistic second-order S-matrix. The S-matrix cross-sections, in general, represent the trend of the measured data over the whole atomic region under investigation. However, these values are, on an average, lower by 10% than the measured ones. The MF cross-sections, in general, exhibit considerable deviations ({approx}30%) from the measured values. In the case of Bi with K-shell binding energy, E{sub K}(Bi)=90.526 keV, just above the incident photon energy (E{sub inc}) of 88.03 keV, the MF cross-section is found to be enormously ({approx}5 times) higher than the measured value. The MF cross-sections in combination with ASFs are in good agreement with the measured values for all the elements except for Pb (E{sub K}(Pb)=88.004 keV) and Bi, where these values are enormously ({approx}28 times) smaller and higher by 31%, respectively.
Determination of the forward slope in $p~p$ and $\\bar p~p$ elastic scattering up to LHC energy
Bourrely, C; Wu, T T
2011-01-01
In the analysis of experimental data on $p p$ (or $\\bar p p$) elastic differential cross section it is customary to define an average forward slope $b$ in the form $\\exp{(-b|t|)}$ where $t$ is the momentum transfer. Taking as working example the results of experiments at Tevatron and SPS, we will show with the help of the impact picture approach, that this simplifying assumption hides interesting information on the complex non-flip scattering amplitude, and that the slope $b$ is not a constant. We investigate the variation of this slope parameter, including a model-independent way to extract this information from an accurate measurement of the elastic differential cross section. An extension of our results to the LHC energy domain is presented in view of future experiments.
Man LUO; Li-Ke JIANG; Yao-Xiong HUANG; Ming XIAO; Bo LI; Guo-Lin ZOU
2004-01-01
Citral refined from Litsea cubeba oil has been found to have a strong influence on fungi,especially Aspergillus flavus. Multiplex microanalysis and quasi-elastic light scattering techniques were applied to study the effects of citral on Aspergillus flavus spores from the levels of membrane, organelle and intracellular macromolecule. It was found that citral injured the wall and the membrane of A. flavus spore,resulting in decrease of its elasticity. After entering the cell, citral not only influenced the genetic expression of mitochondrion reduplication and its morphology, but also changed the aggregation of protein-like macromolecules. As a result, cells, organelles and macromolecules lost their normal structures and functions,eventually leading to the loss of germination ability of A. flavus spores. Since Litsea cubeba oil as food additive and antifungal agent is safe and less poisonous, it is important to elucidate the inhibitory mechanisms of Litsea cubeba oil on the germination ability ofA. flavus spore.
周振功; 王彪
2001-01-01
The scattering of harmonic waves by two collinear symmetric cracks is studied using the non-local theory. A one-dimensional non-local kernel was used to replace a twodimensional one for the dynamic problem to obtain the stress occurring at the crack tips. The Fourier transform was applied and a mixed boundary value problem was formulated. Then a set of triple integral equations was solved by using Schmidt's method. This method is more exact and more reasonable than Eringen' s for solving this problem. Contrary to the classical elasticity solution, it is found that no stress singularity is present at the crack tip. The non- local dynamic elastic solutions yield a finite hoop stress at the crack tip, thus allowing for a fracture criterion based on the maximum dynamic stress hypothesis. The finite hoop stress at the crack tip depends on the crack length, the lattice parameter and the circular frequency of incident wave.
Nicoletopoulos, P
2003-01-01
The variation with energy of the total cross section for elastic electron scattering from atoms of several elements is caused primarily by shape resonances corresponding to the formation of temporary negative ions. It is shown that such cross sections are expressible analytically in terms of a constant background added to a "generalized Fano profile" [Durand Ph, et al (2001) J. Phys. B: At. Mol. Opt. Phys. 34, 1953, ibid (2002) 35, 469]. In three cases (sodium, magnesium and mercury), a detailed consideration proves that this representation is accurate in a fairly wide energy range. Moreover, the related momentum transfer cross sections are tailor-made for studying "elastic" electron transport in terms of the two-term solution of the Boltzmann equation: Not only are the resulting swarm transport coefficients adjustable to the experimental values, but above all they are calculable very easily because the unnormalized energy distribution is obtainable analytically. The ample saving in computational effort is ex...
Elastic properties of type-I clathrate K8Zn4Sn42 determined by inelastic X-ray scattering
Leu, Bogdan M.; Sturza, Mihai; Hong, Jiawang; Alatas, Ahmet; Baran, Volodymyr; Fassler, Thomas F.
2016-01-01
We measured the phonon dispersion at ambient conditions in single-crystal type-I clathrate K8Zn4Sn42, a material with promising thermoelectric properties that has only recently been synthesized, using the high-energy resolution inelastic X-ray scattering (IXS) technique. From the sound velocities along high-symmetry directions, we extracted the elastic constants (C 11, C 12, C 44 = 63.2, 19.1, 21.9 GPa, respectively). Experimental results agree with the predictions from first-principles calculations on the hypothetical, "guest-free", type-I clathrate Sn46. The size of the crystal investigated was several orders of magnitude smaller than what is required for neutron and ultrasonic measurements. Due to this essential property, together with the high-energy resolution, high-momentum-transfer resolution, and the access to the strongest Bragg reflections, IXS is the technique of choice for measuring the full elastic constant tensor for microcrystals.
TU; Mei; HUANG; Yaoxiong
2004-01-01
The laser light scattering technique for non-invasive in situ simultaneous measurements on elastic constants and viscosity coefficients of nematic liquid crystals is introduced. By measuring the autocorrelation function of the scattered light from nematic liquid crystals at different scattering angles, the splay and twist elastic constants K11 and K22 are obtained from the amplitudes of the autocorrelation function, and the viscosity coefficients of (Splay and (Twist are determined using the viscoelastic ratios K11/( Splay and K22/(Twist from the relaxation parameters of the two modes.
Study of the elastic scattering of {sup 6}He on {sup 208}Pb at energies around the Coulomb barrier
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.
Rohdjess, H; 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; Muenstermann, 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
2004-01-01
The EDDA-Detector at the Cooler-Synchrotron COSY/J\\"ulich has been operated with an internal CH$_2$ fiber target to measure proton-proton elastic scattering differential cross sections. For the 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.
The second Born approximation of electron–argon elastic scattering in a bichromatic laser ﬁeld
Bin Zhou; Ming-Yang Zheng; Da-Yong Wen
2012-03-01
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 elements numerically. The dependence of differential cross-section on the relative phase between the two laser components is presented. The results obtained in the ﬁrst and second Born approximations are compared and analysed.
Spin Correlation for pp Elastic Scattering at θc.m.=π2 in the Energy Region of Dibaryon Resonances
Bhatia, T. S.; Glass, G.; Hiebert, J. C.; Kenefick, R. A.; Northcliffe, L. C.; Tippens, W. B.; Boissevain, J. G. J.; Jarmer, J. J.; Simmons, J. E.; Tripard, G. E.; Fitzgerald, D.; Holt, J.; Mokhtari, A.
1982-10-01
Precise measurements are reported of the spin-correlation parameter ANN for 500-800 MeV pp elastic scattering at θc.m.=π2. While not reproducing the large value of ANN reported earlier at 697 MeV, the data show a pronounced maximum in the 90° triplet-to-singlet ratio near the location of the reported 3F3 dibaryon resonance. In contradiction with an earlier report, structure is not found in the moduli of the singlet and triplet amplitudes.
Measurement of the vector and tensor analyzing powers for dp-elastic scattering at 880 MeV
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.
Elastic scattering of. pi. sup + and. pi. sup minus from sup 4 He between 90 and 240 MeV
Brinkmoeller, B.; Blilie, C.L.; Dehnhard, D.; Jones, M.K.; Martinez, G.M.; Nanda, S.K.; Sterbenz, S.M.; Yen, Y. (University of Minnesota, Minneapolis, Minnesota (USA)); Atencio, L.G.; Faucett, J.A.; Greene, S.J.; Morris, C.L.; Seestrom, S.J. (Los Alamos National Laboratory, Los Alamos, New Mexico (USA)); Burleson, G.R.; Dhuga, K.S.; Garnett, R.W. (University of New Mexico, Las Cruces, New Mexico (USA)); Maeda, K. (Tohoku University, Sendai (Japan)); Moore, C.F.; Mordechai, S.; Williams, A.; Yoo, S.H. (University of Texas, Austin, Texas (USA)); Bland, L.C. (University of Pennsylvania, Philadelphia, Pennsylvania (USA))
1991-11-01
In a series of experiments, differential cross sections for elastic scattering of {pi}{sup +} and {pi}{sup {minus}} from {sup 4}He were measured at the Clinton P. Anderson Meson Physics Facility (LAMPF). Data were taken at incident energies between {ital T}{sub {pi}}=90 and 240 MeV using different experimental setups which covered the angular range from far forward ({approx}10{degree}) to far backward angles ({approx}170{degree}). A phase-shift analysis of the data was carried out. The experimental phase shifts are compared with values predicted by a first-order optical model program.
Large-angle elastic scattering of. pi. /sup +/ and. pi. /sup -/ from /sup 16/O at 114 MeV
Dhuga, K.S.; Burleson, G.R.; Faucett, J.A.; Boudrie, R.L.; Cottingame, W.B.; Greene, S.J.; Morris, C.L.; Tanaka, N.; Wang, Z.F.; Nanda, S.
1985-12-01
Elastic cross sections have been measured for the scattering of ..pi../sup +/ and ..pi../sup -/ from /sup 16/O at 114 MeV in the angular range of 115/sup 0/ to 175/sup 0/ (c.m.). Large cross sections and large ..pi../sup +//..pi../sup -/ differences have been observed beyond 140/sup 0/ (c.m.). First-order optical model calculations fail to reproduce the large-angle data. Second-order effects generally improve the fits, but the details of the present data together with the results of earlier measurements at smaller angles have not been satisfactorily explained.
Target-charge dependence of the breakup coupling effects in the elastic scattering of {sup 8}B
Kucuk, Y. [University of Padova, Department of Physics and Astronomy ' ' G. Galilei' ' (Italy); Akdeniz University, Department of Physics, Antalya (Turkey); INFN, Padova (Italy); Aciksoz, E. [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); Akdeniz University, Department of Physics, Antalya (Turkey)
2016-04-15
We perform continuum discretized coupled-channels calculations for the elastic scattering of {sup 8}B on different targets to trace where the Coulomb-nuclear breakup coupling effects start to be dominant in the interaction of the proton halo nuclei. We observe a qualitative difference in angular distributions when the charge of the target increases as seen in the case of neutron halos, but the Coulomb-nuclear interference peak begins to disappear clearly at a relatively smaller value of Z{sub T} for the proton halos. (orig.)
Gardner, A. B.; Howard, S.; Waddington, T. C.; Richardson, R. M.; Tomkinson, J.
1981-05-01
Incoherent quasi-elastic neutron scattering has been used to study the reorientational motions of the cyclopentadienyl rings in ferrocene, nickelocene and ruthenocene. The results for ferrocene show that the activation energy for ring rotation drops above the 164 K phase transition to 4.4 ± 0.5 kJ mol-1 (which is approximately half its low temperature value) but the rings still appear to jump between only five orientations on the observable time scale. At room temperature, the rings in nickelocene appear to behave the same as in ferrocene but in ruthenocene they reorientate much less frequently and resemble those in ferrocene below 164 K.
Measurement of the analyzing power of proton-carbon elastic scattering in the CNI region at RHIC
Jinnouchi, O; Bravar, A; Bunce, G; Dhawan, S; Huang, H; Igo, G; Kanavets, V P; Kurita, K; Okada, H; Saitô, N; Spinka, H; Svirida, D N; Wood, J
2005-01-01
The single transverse spin asymmetry, A_N, of the p-carbon elastic scattering process in the Coulomb Nuclear Interference (CNI) region was measured using an ultra thin carbon target and polarized proton beam in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL). In 2004, data were collected to calibrate the p-carbon process at two RHIC energies (24 GeV, 100 GeV). A_N was obtained as a function of momentum transfer -t. The results were fit with theoretical models which allow us to assess the contribution from a hadronic spin flip amplitude.
Measurement of large-angle $\\pi^{\\pm}p$ elastic scattering at 5 GeV /c
Chabaud, V; Briandet, P; Carlson, Per J; Davier, M; Eide, A; Fleury, P; Gracco, Valerio; Johansson, E; Landby, A; Lehman, P; Morand, R; Mukhin, S; Myrheim, Jan; Treille, D
1972-01-01
The differential cross-section for 5 GeV/c pi /sup +/p and pi /sup -/p elastic scattering have been measured in the c.m. angular region 27 /sup o/< theta /sub cm/ <130 degrees corresponding to 0.5< mod t mod <7.8 (GeV/c)/sup 2/. Dips are observed in both reactions at -t=2.8 and 4.8 (GeV/c)/sup 2/ where the cross-sections are approximately 0.1 mu b /(GeV/c)/sup 2/. (9 refs).
Nikolenko D.M.
2014-03-01
Full Text Available We describe a precise measurement of the ratio of the (e+ p to (e− p elastic scattering cross sections. This comparison is sensitive to the effect of two-photon exchange contributions which may be the cause for inconsistent extractions of the proton form factors obtained using different methods. The experiment was performed at storage ring VEPP–3, Novosibirsk at energies of positron/electron beams of 1.0 and 1.6 GeV with electron/positron scattering angles θ = 65÷105° for the first case and 15÷25° and 55÷75° for the second case. Details of the experiment and the preliminary results are presented.
Elastic and inelastic scattering of {sup 16}O+{sup 64}Zn at near-barrier energies
Tenreiro, C.; Acquadro, J.C.; Freitas, P.A.; Liguori Neto, R. [Universidade de Sao Paulo, IFUSP Laboratorio Pelletron, C.P. 20516-01498-970, Sao Paulo (Brazil); Ramirez, G.; Cuevas, N. [Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago 1 (Chile); Gomes, P.R.; Cabezas, R.; Anjos, R.M. [Departamento de Fisica, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza s/n, Niteroi, R. J., 24210 (Brazil); Copnell, J. [University of Manchester, Physics Department, Schuster Laboratories, Manchester M13 9PL (United Kingdom)
1996-06-01
Elastic and inelastic scattering angular distributions were measured for the {sup 16}O+{sup 64}Zn reaction at bombarding energies close to the Coulomb barrier. The experimental data were analyzed within the optical model and coupled-channel model. An extended dispersion relation of integral quantities using a Gaussian weight was applied, instead of the normal relationship. Within this frame, the optical model parameters obtained from the data are in agreement with the dispersion relation and show the threshold anomaly at energies close to the Coulomb barrier. Analysis of the inelastic scattering angular distributions leads to some indications that an inelastic threshold anomaly is beginning to develop at energies lower than the ones for which our data were taken. {copyright} {ital 1996 The American Physical Society.}
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<=...
Quark–hadron duality constraints on γZ box corrections to parity-violating elastic scattering
N.L. Hall
2016-02-01
Full Text Available We examine the interference γZ box corrections to parity-violating elastic electron–proton scattering in the light of the recent observation of quark–hadron duality in parity-violating deep-inelastic scattering from the deuteron, and the approximate isospin independence of duality in the electromagnetic nucleon structure functions down to Q2≈1 GeV2. Assuming that a similar behavior also holds for the γZ proton structure functions, we find that duality constrains the γZ box correction to the proton's weak charge to be ℜe□γZV=(5.4±0.4×10−3 at the kinematics of the Qweak experiment. Within the same model we also provide estimates of the γZ corrections for future parity-violating experiments, such as MOLLER at Jefferson Lab and MESA at Mainz.
Register, D. F.; Trajmar, S.
1984-01-01
Relative elastic-scattering differential cross sections were measured in the 5-100-eV impact energy and 10-145 deg angular ranges. Normalization of these cross sections was achieved by utilizing accurate total electron-scattering cross sections. A phase-shift analysis of the angular distributions in terms of real phase shifts has been carried out. From the differential cross sections, momentum-transfer cross sections were obtained and the values of the critical energy and angle were established (associated with the lowest value of the differential cross section) as 62.5 + or - 2.5 eV and 101.7 deg + or - 1.5 deg, respectively. The present phase shifts, the critical parameters, and differential, integral, and momentum-transfer cross sections are compared to previous experimental and theoretical results. The error associated with the present data is about 10 percent.
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.
Study of the Quasi-Elastic Scattering in the NOvA Detector Prototype
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.
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...
Quasi-Elastic Neutron Scattering (QENS) Studies of Hydrogen Dynamics for Nano-Confined NaAlH4
Dobbins, Tabbetha; Narasegowda, Shathabish; Brown, Craig; Tyagi, Madhusudan; Jenkins, Timothy
The hydrogen dynamics of nano-confined sodium alanate (NaAlH4) has been studied using quasi-elastic neutron scattering (QENS). Results indicate thermodynamic destabilization is responsible for reduced desorption temperatures of NaAlH4 upon confinement within the nanopores of a metal organic framework (MOF). Both the bulk (microscale) NaAlH4 and the nanoconfined NaAlH4 data were fitted to re-orientation models which yielded corresponding percent mobile hydrogen and jump lengths. The jump lengths calculated from the nano-NaAlH4 were ~2.5 Å, and in conformity with those jump lengths determined for bulk NaAlH4 of ~2.3 Å. As much as 18 % of the hydrogen atoms were estimated to be mobile in the nano-NaAlH4 sample even at relatively low temperatures of 350 K. In contrast, bulk NaAlH4 shows less than 7 % mobile H-atoms even at higher temperatures of ~450 K. The activation energy for the long range is 3.1meV. Quasi-Elastic Neutron Scattering (QENS) Studies of Hydrogen Dynamics for Nano-Confined NaAlH4.
Luzzati, Vittorio; Benoit, Evelyne; Charpentier, Gilles; Vachette, Patrice
2004-10-08
The effects of several agents, sugars, isotonic KCl, and a variety of drugs, on the structure of the axonal membranes of unmyelinated pike olfactory nerve have been studied by synchrotron radiation X-ray scattering experiments. The main effects of the sugars are: (i) to increase the electron density of the extra-axonal space and thereby yield the absolute scale of the electron density profile; (ii) to osmotically stress the membrane and thus yield its elastic modulus of area compressibility, since the related strain, thickness dilation, is directly determined by the X-ray scattering experiments. Exposure to isotonic KCl, a depolarizing agent, induces membrane thickness to increase. The energy liberated in this process is a function of the amplitude of the dilation and of the elastic modulus of the membrane. This energy turns out to be close to the thermal energy liberated by the pike olfactory nerve during the initial phase of action potential that has previously been measured by others. Electrical depolarization thus seems to be accompanied by a thickness dilation of the axonal membrane. Another effect of isotonic KCl is to induce a large fraction of the membranes to pair by tight apposition of their extra-axonal faces. Local anaesthetics and some drugs have the effect of altering membrane thickness. All these observations are interpreted in terms of a modulation of the conformational disorder of the hydrocarbon chains of the lipid molecules.
Kozier, K. S.; Roubtsov, D. [AECL, Chalk River Laboratories, Chalk River, ON (Canada); Plompen, A. J. M.; Kopecky, S. [EC-JRC, Inst. for Reference Materials and Measurements, Retieseweg 111, 2440 Geel (Belgium)
2012-07-01
The thermal neutron-elastic-scattering cross-section data for {sup 16}O used in various modern evaluated-nuclear-data libraries were reviewed and found to be generally too high compared with the best available experimental measurements. Some of the proposed revisions to the ENDF/B-VII.0 {sup 16}O data library and recent results from the TENDL system increase this discrepancy further. The reactivity impact of revising the {sup 16}O data downward to be consistent with the best measurements was tested using the JENDL-3.3 {sup 16}O cross-section values and was found to be very small in MCNP5 simulations of the UO{sub 2} and reactor-recycle MOX-fuel cases of the ANS Doppler-defect numerical benchmark. However, large reactivity differences of up to about 14 mk (1400 pcm) were observed using {sup 16}O data files from several evaluated-nuclear-data libraries in MCNP5 simulations of the Los Alamos National Laboratory HEU heavy-water solution thermal critical experiments, which were performed in the 1950's. The latter result suggests that new measurements using HEU in a heavy-water-moderated critical facility, such as the ZED-2 zero-power reactor at the Chalk River Laboratories, might help to resolve the discrepancy between the {sup 16}O thermal elastic-scattering cross-section values and thereby reduce or better define its uncertainty, although additional assessment work would be needed to confirm this. (authors)