Spin asymmetry in resonant electron-hydrogen elastic scattering
International Nuclear Information System (INIS)
McCarthy, I.E.; Shang, Bo.
1993-02-01
Differential cross sections and asymmetries at 90 deg. and 30 deg are calculated for electron-hydrogen elastic scattering over the energies of the lowest 1 S and 3 P resonances using a nine-state coupled-channels calculation with and without continuum effects, which are represented by an equivalent-local polarization potential. The polarization potential improves agreement with experiment in general for the spin-averaged cross sections. It is suggested that continuum effects would be critically tested by asymmetry measurement at 30 deg over the 1 S resonance. 7 refs., 4 figs
Observing shape resonances in ultraslow H^++H elastic scattering
Macek, J. H.; Schultz, D. R.; Ovchinnikov, S. Yu.; Krstic, P. S.
2004-05-01
We have calculated highly accurate elastic and charge transfer cross sections for proton-hydrogen scattering at energies 0.0001-10 eV, using fully quantal approach (P.S. Krstic and D.R. Schultz, J. Phys. B 32, 3485 (1999)). A number of resonances are observed. We calculate the positions and widths of the shape resonances in the effective potentials for various orbital angular momenta (J. H. Macek and S. Yu. Ovchinnikov, Phys. Rev. A 50, 468 (1994)). These correlate well with the observed resonances. We acknowledge support from the US DOE through ORNL, managed by UT-Battelle, LLC under contract DE-AC05-00OR22725.
Energy Technology Data Exchange (ETDEWEB)
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)
International Nuclear Information System (INIS)
Leader, Elliot
1991-01-01
With very few unexplained results to challenge conventional ideas, physicists have to look hard to search for gaps in understanding. An area of physics which offers a lot more than meets the eye is elastic and diffractive scattering where particles either 'bounce' off each other, emerging unscathed, or just graze past, emerging relatively unscathed. The 'Blois' workshops provide a regular focus for this unspectacular, but compelling physics, attracting highly motivated devotees
Resonance estimates for single spin asymmetries in elastic electron-nucleon scattering
International Nuclear Information System (INIS)
Barbara Pasquini; Marc Vanderhaeghen
2004-01-01
We discuss the target and beam normal spin asymmetries in elastic electron-nucleon scattering which depend on the imaginary part of two-photon exchange processes between electron and nucleon. We express this imaginary part as a phase space integral over the doubly virtual Compton scattering tensor on the nucleon. We use unitarity to model the doubly virtual Compton scattering tensor in the resonance region in terms of γ* N → π N electroabsorption amplitudes. Taking those amplitudes from a phenomenological analysis of pion electroproduction observables, we present results for beam and target normal single spin asymmetries for elastic electron-nucleon scattering for beam energies below 1 GeV and in the 1-3 GeV region, where several experiments are performed or are in progress
International Nuclear Information System (INIS)
Dou, L.; Kauppila, W.E.; Kwan, C.K.; Stein, T.S.
1993-01-01
We have measured absolute values of elastic differential cross sections (DCS's) for positron (e + ) scattering by argon (8.7-300 eV), krypton (6.7-400 eV), and also neon (13.6-400 eV) using a crossed-beam experimental setup. When the DCS's are plotted at fixed scattering angles of 30 degrees, 60 degrees, 90 degrees, and 120 degrees versus energy it has been found that well-defined resonance-like structures were found at an energy of 55-60 eV for argon and at 25 and 200 eV for krypton, with a broader structure found between 100-200 eV for neon. These observed resonance-like structures are unusual because they occur at energies well above the known inelastic thresholds for these atoms. They may represent examples of open-quotes coupled channel shape resonancesclose quotes, first predicted by Higgins and Burke for e + -H scattering in the vicinity of 36 eV (width ∼ 4 eV), which occurs only when both the elastic and positronium formation scattering channels are considered together. A more recent e + -H calculation by Hewitt et al. supports the Higgins and Burke prediction. These predictions and the present observations suggest the existence of a new type of atomic scattering resonance
Scattering phase shift for elastic two pion scattering and the rho resonance in lattice QCD
Energy Technology Data Exchange (ETDEWEB)
Gutzwiller, Simone
2012-10-08
In this thesis we use lattice QCD to compute scattering phase shifts for elastic two-pion scattering in the isospin I=1 channel. Using Luescher's formalism, we derive the scattering phase shifts for different total momenta of the two-pion system in a non-rest frame. Furthermore we analyse the symmetries of the non-rest frame lattices and construct 2-pion and rho operators transforming in accordance with these symmetries. The data was collected for a 32{sup 3} x 64 and a 40{sup 3} x 64 lattice with N{sub f}=2 clover improved Wilson fermions at a pion mass around 290 MeV and a lattice spacing of about 0.072 fm.
Scattering phase shift for elastic two pion scattering and the rho resonance in lattice QCD
International Nuclear Information System (INIS)
Gutzwiller, Simone
2012-01-01
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 3 x 64 and a 40 3 x 64 lattice with N f =2 clover improved Wilson fermions at a pion mass around 290 MeV and a lattice spacing of about 0.072 fm.
Regeta, Khrystyna; Allan, Michael; Winstead, Carl; McKoy, Vincent; Mašín, Zdeněk; Gorfinkiel, Jimena D
2016-01-14
We measured differential cross sections for elastic (rotationally integrated) electron scattering on pyrimidine, both as a function of angle up to 180(∘) at electron energies of 1, 5, 10, and 20 eV and as a function of electron energy in the range 0.1-14 eV. The experimental results are compared to the results of the fixed-nuclei Schwinger variational and R-matrix theoretical methods, which reproduce satisfactorily the magnitudes and shapes of the experimental cross sections. The emphasis of the present work is on recording detailed excitation functions revealing resonances in the excitation process. Resonant structures are observed at 0.2, 0.7, and 4.35 eV and calculations for different symmetries confirm their assignment as the X̃(2)A2, Ã(2)B1, and B̃(2)B1 shape resonances. As a consequence of superposition of coherent resonant amplitudes with background scattering the B̃(2)B1 shape resonance appears as a peak, a dip, or a step function in the cross sections recorded as a function of energy at different scattering angles and this effect is satisfactorily reproduced by theory. The dip and peak contributions at different scattering angles partially compensate, making the resonance nearly invisible in the integral cross section. Vibrationally integrated cross sections were also measured at 1, 5, 10 and 20 eV and the question of whether the fixed-nuclei cross sections should be compared to vibrationally elastic or vibrationally integrated cross section is discussed.
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.
Sanz, A S; Miret-Artés, S
2005-01-01
The elastic resonant scattering of He atoms off the Cu(117) surface is fully described with the formalism of quantum trajectories provided by Bohmian mechanics. Within this theory of quantum motion, the concept of trapping is widely studied and discussed. Classically, atoms undergo impulsive collisions with the surface, and then the trapped motion takes place covering at least two consecutive unit cells. However, from a Bohmian viewpoint, atom trajectories can smoothly adjust to the equipotential energy surface profile in a sort of sliding motion; thus the trapping process could eventually occur within one single unit cell. In particular, both threshold and selective adsorption resonances are explained by means of this quantum trapping considering different space and time scales. Furthermore, a mapping between each region of the (initial) incoming plane wave and the different parts of the diffraction and resonance patterns can be easily established, an important issue only provided by a quantum trajectory formalism. (c) 2005 American Institute of Physics.
Elastic and Raman scattering of photons from the giant dipole resonance
International Nuclear Information System (INIS)
Bar-Noy, T.
1978-12-01
In the present work we investigated nuclear Raman and elastic scattering of photons from the Giant Dipole Resonance (GDR) of medium and heavy nuclei. The photons beams were obtained from thermal neutron capture on V, Fe, Ni, Cu and Cr discs, utilizing the IRR-2 reactor. Nine targets, 159 Tb, 165 Ho, 175 Lu, 181 Ta, 197 Au, 209 Bi, 232 Th, 237 Np, and 238 U, representing all spherical and deformed nuclei in the region of medium and heavy nuclei, were used. As preliminary works, we discovered and investigated the 11.4 MeV γ-line, measured the attenuation coefficients at 9 and 11.4 MeV, performed a numerical calculation of Delbrueck amplitudes and modified the Simple Rotator Model (SRM). The absolute scattering cross-sections were measured for each scatterer at 4-8 different energies, and angular distributions in the range 90 deg to 140 deg were carried out at 9 MeV and 11.4 MeV. The experimental results were compared with theoretical predictions of the modified SRM and the Dynamic Collective Model (DCM). The results proved that the modified SRM describes appropriately the scattering from the GDR, including elastic and Raman absolute cross-sections and their angular distributions. (author)
International Nuclear Information System (INIS)
Nakagawa, Masayuki; Ishiguro, Yukio; Tokuno, Yukio.
1978-01-01
The self-shielding factors for elastic removal cross sections of light and medium weight nuclides were calculated for the parameter, σ 0 within the conventional concept of the group constant sets. The numerical study were performed for obtaining a simple and accurate method. The present results were compared with the exact values and the conventional ones, and shown to be remarkably improved. It became apparent that the anisotropy of the elastic scattering did not affect to the self-shielding factors though it did to the infinite dilution cross sections. With use of the present revised set, the neutron flux were calculated in an iron medium and in a prototype FBR and compared with those by the fine spectrum calculations and the conventional set. The present set showed the considerable improvement in the vicinity of the large resonance regions of sodium, iron and oxygen. (auth.)
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.
International Nuclear Information System (INIS)
Mermaz, M.C.
1984-01-01
Diffraction and refraction play an important role in particle elastic scattering. The optical model treats correctly and simultaneously both phenomena but without disentangling them. Semi-classical discussions in terms of trajectories emphasize the refractive aspect due to the real part of the optical potential. The separation due to to R.C. Fuller of the quantal cross section into two components coming from opposite side of the target nucleus allows to understand better the refractive phenomenon and the origin of the observed oscillations in the elastic scattering angular distributions. We shall see that the real part of the potential is responsible of a Coulomb and a nuclear rainbow which allows to determine better the nuclear potential in the interior region near the nuclear surface since the volume absorption eliminates any effect of the real part of the potential for the internal partial scattering waves. Resonance phenomena seen in heavy ion scattering will be discussed in terms of optical model potential and Regge pole analysis. Compound nucleus resonances or quasi-molecular states can be indeed the more correct and fundamental alternative
Single-particle resonance levels in {sup 14}O examined by N13+p elastic resonance scattering
Energy Technology Data Exchange (ETDEWEB)
Teranishi, T. [Dept. of Physics, Kyushu Univ., 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan)]. E-mail: teranishi@nucl.phys.kyushu-u.ac.jp; Kubono, S. [Center for Nuclear Study (CNS), Univ. of Tokyo, Wako Branch at RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Yamaguchi, H. [Center for Nuclear Study (CNS), Univ. of Tokyo, Wako Branch at RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); He, J.J. [Center for Nuclear Study (CNS), Univ. of Tokyo, Wako Branch at RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Saito, A. [Center for Nuclear Study (CNS), Univ. of Tokyo, Wako Branch at RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Fujikawa, H. [Center for Nuclear Study (CNS), Univ. of Tokyo, Wako Branch at RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Amadio, G. [Center for Nuclear Study (CNS), Univ. of Tokyo, Wako Branch at RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Niikura, M.; Shimoura, S. [Center for Nuclear Study (CNS), Univ. of Tokyo, Wako Branch at RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Wakabayashi, Y. [Dept. of Physics, Kyushu Univ., 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan)]|[Center for Nuclear Study (CNS), Univ. of Tokyo, Wako Branch at RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Nishimura, S.; Nishimura, M. [RIKEN Nishina Center for Accelerator-Based Science, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Moon, J.Y.; Lee, C.S. [Dept. of Physics, Chung-Ang Univ., Seoul 156-756 (Korea, Republic of); Odahara, A. [Nishinippon Inst. of Technology, Kanda, Fukuoka 800-0394 (Japan); Sohler, D. [Inst. of Nuclear Research (ATOMKI), H-4001 Debrecen, P.O. Box 51 (Hungary); Khiem, L.H. [Inst. of Physics and Electronics (IOP), Vietnamese Academy for Science and Technology (VAST), 10 Daotan, Congvi, Badinh, P.O. Box 429-BOHO, Hanoi 10000 (Viet Nam); Li, Z.H.; Lian, G.; Liu, W.P. [China Inst. of Atomic Energy, P.O. Box 275(46), Beijing 102413 (China)
2007-06-28
Single-particle properties of low-lying resonance levels in {sup 14}O have been studied efficiently by utilizing a technique of proton elastic resonance scattering with a {sup 13}N secondary beam and a thick proton target. The excitation functions for the N13+p elastic scattering were measured over a wide energy range of E{sub CM}=0.4-3.3 MeV and fitted with an R-matrix calculation. A clear assignment of J{sup {pi}}=2{sup -} has been made for the level at E{sub x}=6.767(11) MeV in {sup 14}O for the first time. The excitation functions show a signature of a new 0{sup -} level at E{sub x}=5.71(2) MeV with {gamma}=400(100) keV. The excitation energies and widths of the {sup 14}O levels are discussed in conjunction with the spectroscopic structure of A=14 nuclei with T=1.
Pion elastic scattering from polarized 13C in the energy region of the P33 resonance
International Nuclear Information System (INIS)
Yifen, Yen
1992-08-01
Asymmetries (A y ) and differential cross sections (dσ/dΩ) were measured for π + and π - elastic scattering using polarized and unpolarized 13 C targets. The experiment was done at the Los Alamos Meson Physics Facility with the pion beam from the Low Energy Pion channel. The scattered pions were detected with the Large Acceptance Spectrometer. The 13 C nuclei in 13 C-enriched 1-butanol were polarized by the dynamic nuclear polarilization method. Angular distributions of both A y and dσ/dΩ were measured below the P 33 resonance at the incident energy of 130 MeV for π + and π - , and above the resonance at 223 MeV for π + and at 226 MeV for π - . In addition, A y and dσ/dΩ were measured in a range of momentum transfers, 1.75 ≤ q ≤ 2.05 fm - , at several energies. At 130 MeV, the values of A y are significantly different from zero for π - scattering. For π + at 130 MeV and for both π - and π + at all other energies, the A y are mostly consistent with zero. Theoretical analyses were done using different nuclear structure models. The data were not reproduced by the presently available nuclear wave functions. It was found that the asymmetry is strongly sensitive to the quadrupole spin flip part of the transition. The data of this thesis complement measurements of the magnetic form factor from electron scattering. In attempts to fit both the asymmetry and the magnetic form factor, it was found that the pion asymmetry data are not reproduced by the wavefunctions which fit the magnetic form factor at low momentum transfers
Analyzing power for π-p elastic scattering in the energy region of the Roper resonance
International Nuclear Information System (INIS)
Mokhtari, A.; Briscoe, W.J.; Eichon, A.D.; Fitzgerald, D.H.; Kim, G.J.; Nefkens, B.M.K.; Wightman, J.A.; Sadler, M.E.
1986-01-01
High-precision measurements of the analyzing power A/sub N/ in π - p elastic scattering at p/sub π/ = 471--687 MeV/c are presented and compared with the results of recent πN partial-wave analyses (PWA's) by the Karlsruhe-Helsinki, CMU-LBL, and VPI groups. While agreeing with the main features of the measured angular dependence of A/sub N/, the three PWA's yield larger values than the measurements at forward angles at p/sub π/ = 471, 547, and 625 MeV/c. At 687 MeV/c the PWA's do not agree with the data at far backward angles. We estimate the effect of our data on the phase shifts in this energy region, which includes the Roper resonance
Coupling effects of giant resonances on the elastic and inelastic scattering of fast neutrons
International Nuclear Information System (INIS)
Delaroche, J.P.; Tornow, W.
1983-01-01
While the inelastic scattering of high energy hadrons is commonly used for the study of giant resonances in nuclei, it is just recently that one has thought to take into account these states in the analysis of proton scattering at low incident energies (E 0 and S 1 . (Auth.)
π−-12C elastic scattering above the ∆ resonance using diffraction ...
Indian Academy of Sciences (India)
the diffraction model framework using the recently proposed parametrization of the phase- ... For example, Hong and Kim [7] have used the conventional six- ... In a recent article, Ahmad and Arafah [9] (hereafter to be referred to as I) .... Here, it may be added that in multiparameter fitting of the elastic scattering angular.
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
π- -12C elastic scattering above the Δ resonance using diffraction model
International Nuclear Information System (INIS)
Arafah, M.R.
2008-01-01
Phenomenological analysis of the π - - 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 recently proposed parameterization 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. (author)
Mitri, Farid G
2012-08-01
This work presents the general theory of resonance scattering (GTRS) by an elastic spherical shell immersed in a nonviscous fluid and placed arbitrarily in an acoustic beam. The GTRS formulation is valid for a spherical shell of any size and material regardless of its location relative to the incident beam. It is shown here that the scattering coefficients derived for a spherical shell immersed in water and placed in an arbitrary beam equal those obtained for plane wave incidence. Numerical examples for an elastic shell placed in the field of acoustical Bessel beams of different types, namely, a zero-order Bessel beam and first-order Bessel vortex and trigonometric (nonvortex) beams are provided. The scattered pressure is expressed using a generalized partial-wave series expansion involving the beam-shape coefficients (BSCs), the scattering coefficients of the spherical shell, and the half-cone angle of the beam. The BSCs are evaluated using the numerical discrete spherical harmonics transform (DSHT). The far-field acoustic resonance scattering directivity diagrams are calculated for an albuminoidal shell immersed in water and filled with perfluoropropane gas, by subtracting an appropriate background from the total far-field form function. The properties related to the arbitrary scattering are analyzed and discussed. The results are of particular importance in acoustical scattering applications involving imaging and beam-forming for transducer design. Moreover, the GTRS method can be applied to investigate the scattering of any beam of arbitrary shape that satisfies the source-free Helmholtz equation, and the method can be readily adapted to viscoelastic spherical shells or spheres.
International Nuclear Information System (INIS)
Chyla, K.; Jarczyk, L.; Maciuk, B.; Zipper, W.
1976-01-01
Alpha particle scattering from 28 Si has been studied at five bombarding energies from 23.5 to 28.5 MeV. iota-dependent resonance absorption has been introduced to the optical model analysis of 28 Si (α,β) 28 Si reaction. (author)
Resonant elastic scattering of 15O and a new reaction path in the CNO cycle
International Nuclear Information System (INIS)
Stefan, Gheorghe Iulian
2006-12-01
This work presents a very accurate experimental method based on radioactive beams for the study of the spectroscopical properties of unbound states. It makes use of inverse kinematical elastic scattering of the ions of an radioactive beam from a target of stable nuclei. An application of the method for the study of radioactive nuclei of astrophysical interests is given, namely of 19 Ne and 16 F nuclei. It is shown that on the basis of the properties of proton-emitting unbound levels of 19 Ne one can develop a method of experimental study of nova explosions. It is based on observation of gamma emissions following the gamma decays of the radionuclides generated in the explosion. The most interesting radioactive nucleus involved in this process is 18 F the yield of which depends strongly on the rate of 18 F(p,α) 15 O reaction. This yield depends in turn of the properties of the states of the ( 18 F + p) compound nucleus, i.e. the 19 Ne nucleus. In addition it was studied the unbound 16 F nucleus also of astrophysical significance in 15 O rich environment. Since 16 F is an unbound nucleus the reaction of 15 O with protons, although abundant in most astrophysical media, appears to be negligible. Thus the question that was posed was whether the exotic 15 O(p,β + ) 16 O resonant reaction acquires some importance in various astrophysical media. In this work one describes a novel approach to study the reaction mechanisms which could change drastically the role of non-bound nuclei in stellar processes. One implies this mechanism to the processes (p,γ)(β) + and (p,γ) (p,γ) within 15 O rich media. The experimental studies of the 19 Ne and 16 F were carried out with a radioactive beam of 15 O ions of very low energy produced by SPIRAL at GANIL. To improve the energy resolution thin targets were used with a 0 angle of observation relative to the beam direction. There are stressed the advantages of this approach and one gives details concerning the method of separation of
Energy Technology Data Exchange (ETDEWEB)
Aprile, E; Cantale, G; Degli-Agosti, S; Hausammann, R; Heer, E; Hess, R; Lechanoine-LeLuc, C; Leo, W; Morenzoni, S; Onel, Y [Geneva Univ. (Switzerland). Dept. de Physique Nucleaire et Corpusculaire
1983-01-01
The aim of the elastic pp experimental program at SIN was to measure enough spin dependent parameters in order to do a direct experimental reconstruction of the elastic scattering amplitudes at a few energies between 400 and 600 MeV and at several angles between 38/sup 0/ cm and 90/sup 0/ cm. This reconstruction was not possible until recently due to lack of experimental data. Information instead has come mainly from phase shift analysis (PSA). The only way to extract the elastic scattering amplitudes without any hypotheses except those of basic symmetries, is to measure a sufficient set of spin dependent parameters at a given angle and energy. With this in view, the authors have measured at 448, 494, 515, 536 and 579 MeV, the polarization, the spin correlation parameters Asub(00nn), Asub(00ss), Asub(00kk), Asub(00ks), the 2-spin parameters Dsub(n0n0), Ksub(n00n), Dsub(s'0s0), Dsub(s'0k0) and the 3-spin parameters Msub(s'0sn), Msub(s'0kn) between 34/sup 0/ cm and 118/sup 0/ cm. A few of these parameters have also been measured at 560 and 470 MeV and at a few energies below 448 MeV. The indices refer to the polarization orientation of the scattered, recoil, beam and target particle respectively.
Resonant heavy-ion elastic scattering from s-d shell nuclei
International Nuclear Information System (INIS)
DeVries, R.M.
1978-01-01
Angular distributions at angles 130 less than theta/sub cm/ less than 180 0 were measured for 12 C + 28 Si, 32 S, 40 Ca as well as 9 Be, 13 C + 28 Si in the energy range 20 MeV less than or equal to E/sub cm/ less than or equal to 35 MeV. Cross sections rising towards 180 0 are observed for all reactions. Excitation functions for the back-angle enhancement show distinct structures, most pronounced for 12 C + 28 Si. Angular distributions for 12 C, especially those corresponding to peaks in the excitation function show oscillations of the type vertical bar P/sub J/(cos theta) vertical bar 2 . The 12 C back-angle enhancement decreases with target mass. Backscattering of the nonalpha nuclei 9 Be and 13 C is reduced by about two orders of magnitude in comparison with 12 C. Similar measurements for the 28 Si( 12 C, 16 O) 24 Mg reaction and 16 O + 24 Mg elastic scattering allow comparison of reaction data with the corresponding entrance and exit channel data. Standard theoretical approaches fail to explain all the observed effects
Elastic scattering and quasi-elastic transfers
International Nuclear Information System (INIS)
Mermaz, M.C.
1978-01-01
Experiments are presented which it will be possible to carry out at GANIL on the elastic scattering of heavy ions: diffraction phenomena if the absorption is great, refraction phenomena if absorption is low. The determination of the optical parameters can be performed. The study of the quasi-elastic transfer reactions will make it possible to know the dynamics of the nuclear reactions, form exotic nuclei and study their energy excitation spectrum, and analyse the scattering and reaction cross sections [fr
International Nuclear Information System (INIS)
Chauveau, J.
1981-01-01
This work describes a search for narrow baryon resonances (of masses between 3.4 and 5 GeV) through a π - p large angle elastic scattering formation experiment. An optimization of the sensitivity of the experiment to detect resonances is obtained by the measurement of the central part of the angular distribution (/cos theta*/ -4 . The apparatus and data analysis are described in details. No narrow resonance has been found, the sensitivity of the experiment being characterized by a width GAMMA approximately equal to 1 MeV and an elasticity x approximately equal to 0.01. Finally, the differential cross section measurement is compared to some parton models [fr
CONFERENCE: Elastic and diffractive scattering
Energy Technology Data Exchange (ETDEWEB)
White, Alan
1989-09-15
Elastic scattering, when particles appear to 'bounce' off each other, and the related phenomena of diffractive scattering are currently less fashionable than the study of hard scattering processes. However this could change rapidly if unexpected results from the UA4 experiment at the CERN Collider are confirmed and their implications tested. These questions were highlighted at the third 'Blois Workshop' on Elastic and Diffractive Scattering, held early in May on the Evanston campus of Northwestern University, near Chicago.
First measurement of 30S+α resonant elastic scattering for the 30S(α ,p ) reaction rate
Kahl, D.; Yamaguchi, H.; Kubono, S.; Chen, A. A.; Parikh, A.; Binh, D. N.; Chen, J.; Cherubini, S.; Duy, N. N.; Hashimoto, T.; Hayakawa, S.; Iwasa, N.; Jung, H. S.; Kato, S.; Kwon, Y. K.; Nishimura, S.; Ota, S.; Setoodehnia, K.; Teranishi, T.; Tokieda, H.; Yamada, T.; Yun, C. C.; Zhang, L. Y.
2018-01-01
Background: Type I x-ray bursts are the most frequently observed thermonuclear explosions in the galaxy, resulting from thermonuclear runaway on the surface of an accreting neutron star. The 30S(α ,p ) reaction plays a critical role in burst models, yet insufficient experimental information is available to calculate a reliable, precise rate for this reaction. Purpose: Our measurement was conducted to search for states in 34Ar and determine their quantum properties. In particular, natural-parity states with large α -decay partial widths should dominate the stellar reaction rate. Method: We performed the first measurement of 30S+α resonant elastic scattering up to a center-of-mass energy of 5.5 MeV using a radioactive ion beam. The experiment utilized a thick gaseous active target system and silicon detector array in inverse kinematics. Results: We obtained an excitation function for 30S(α ,α ) near 150∘ in the center-of-mass frame. The experimental data were analyzed with R -matrix calculations, and we observed three new resonant patterns between 11.1 and 12.1 MeV, extracting their properties of resonance energy, widths, spin, and parity. Conclusions: We calculated the resonant thermonuclear reaction rate of 30S(α ,p ) based on all available experimental data of 34Ar and found an upper limit about one order of magnitude larger than a rate determined using a statistical model. The astrophysical impact of these two rates has been investigated through one-zone postprocessing type I x-ray burst calculations. We find that our new upper limit for the 30S(α ,p )33Cl rate significantly affects the predicted nuclear energy generation rate during the burst.
Directory of Open Access Journals (Sweden)
Giovanni Carlotti
2018-01-01
Full Text Available There is currently a renewed interest in the development of experimental methods to achieve the elastic characterization of thin films, multilayers and acoustic resonators operating in the GHz range of frequencies. The potentialities of surface Brillouin light scattering (surf-BLS for this aim are reviewed in this paper, addressing the various situations that may occur for the different types of structures. In particular, the experimental methodology and the amount of information that can be obtained depending on the transparency or opacity of the film material, as well as on the ratio between the film thickness and the light wavelength, are discussed. A generalization to the case of multilayered samples is also provided, together with an outlook on the capability of the recently developed micro-focused scanning version of the surf-BLS technique, which opens new opportunities for the imaging of the spatial profile of the acoustic field in acoustic resonators and in artificially patterned metamaterials, such as phononic crystals.
CONFERENCE: Elastic and diffractive scattering
International Nuclear Information System (INIS)
White, Alan
1989-01-01
Elastic scattering, when particles appear to 'bounce' off each other, and the related phenomena of diffractive scattering are currently less fashionable than the study of hard scattering processes. However this could change rapidly if unexpected results from the UA4 experiment at the CERN Collider are confirmed and their implications tested. These questions were highlighted at the third 'Blois Workshop' on Elastic and Diffractive Scattering, held early in May on the Evanston campus of Northwestern University, near Chicago
High energy elastic hadron scattering
International Nuclear Information System (INIS)
Fearnly, T.A.
1986-04-01
The paper deals with the WA7 experiment at the CERN super proton synchrotron (SPS). The elastic differential cross sections of pion-proton, kaon-proton, antiproton-proton, and proton-proton at lower SPS energies over a wide range of momentum transfer were measured. Some theoretical models in the light of the experimental results are reviewed, and a comprehensive impact parameter analysis of antiproton-proton elastic scattering over a wide energy range is presented. A nucleon valence core model for high energy proton-proton and antiproton-proton elastic scattering is described
International Nuclear Information System (INIS)
Takahashi, Toshiyuki
1995-11-01
Differential cross sections of the pion elastic scattering in the GeV/c region were systematically measured by using a newly constructed superconducting kaon spectrometer at KEK. The pion incident momenta were 610, 710, 790, and 895 MeV/c for 12 C(π - , π - ) 12 C and 790 MeV/c for 208 Pb(π ± , π ± ) 208 Pb. We have obtained the cross sections with absolute normalization uncertainty of about 10%. The π - -p scattering data measured with a CH target agree well with the phase-shift calculations, which confirms the accuracy of the absolute values of the cross sections. The angular distributions of the differential cross sections for 12 C were compared with calculations by a first-order optical potential model. The calculation reproduces the data at forward scattering-angle regions except at 610 MeV/c, although it underestimates at large-angle region. The present data at 790 MeV/c are in between the BNL data at 800 MeV/c and the calculation, although our data are consistent with the BNL data within their systematic errors. The incident momentum dependence of σ total , σ R , and σ elastic , which were extracted by fitting the angular distributions, is different from that of the calculation with free π-N elementary amplitudes. It is well explained by taking account of Fermi motion. The 208 Pb data are well reproduced by the optical potential model. The root mean square radius of the neutron distribution has been deduced from π + and π - elastic scattering for the first time. Although the result has a model ambiguity, it agrees with that deduced from the proton elastic scattering. It is, however, smaller than the prediction of the relativistic Hartree calculation. (author). 55 refs
International Nuclear Information System (INIS)
Pizzi, J.R.
1975-01-01
In a first part, the kinematical conditions which are chosen to study quasi free scattering reactions are presented, as well as the impulse approximation which is used to interpret the experimental data. Then, the evolution of the study of these reactions in the last few years is analyzed. Three recent experiments are presented and discussed. Two of them deal with α-clusters studied by (p,pα) reaction at 157 and 600MeV. The third is concerned with d, t and 3 He clusters studied by (p,px) reaction at 75MeV [fr
International Nuclear Information System (INIS)
Gaillard, Y.R.
1975-01-01
Angular distributions of analyzing power and differential cross section have been measured for the elastic and inelastic scattering of polarized protons on 12 C, up to 12.7MeV excitation energy. Incident energy varied from 19 to 23MeV by steps of about 200keV, the cyclotron beam energy, varying by steps of about 1MeV, was measured using crossover techniques. Fine steps of energy were obtained by use of carbon absorbers. Elastic scattering data were analyzed using a linear energy-dependent optical model. Data for the level at 4.4MeV excitation energy were analyzed using coupled channel calculations. Preliminary results for the level (1 - , Esub(x)=12.7MeV) were analyzed including giant resonances as doorways states in inelastic scattering, according to Geramb-Amos formalism. This analysis shows that it should be possible to study high-lying giant resonances through their contribution to low-lying state excitation [fr
DEFF Research Database (Denmark)
Andersen, Christian Walther; Bulava, John; Hörz, Ben
2018-01-01
We present the first direct determination of meson-baryon resonance parameters from a scattering amplitude calculated using lattice QCD. In particular, we calculate the elastic I=3/2, p-wave nucleon-pion amplitude on a single ensemble of Nf=2+1 Wilson-clover fermions with mπ=280 MeV and mK=460 Me......V. At these quark masses, the Δ(1232) resonance pole is found close to the N-π threshold and a Breit-Wigner fit to the amplitude gives gΔNπBW=19.0(4.7) in agreement with phenomenological determinations.......We present the first direct determination of meson-baryon resonance parameters from a scattering amplitude calculated using lattice QCD. In particular, we calculate the elastic I=3/2, p-wave nucleon-pion amplitude on a single ensemble of Nf=2+1 Wilson-clover fermions with mπ=280 MeV and mK=460 Me...
Kaspar, Jan; Deile, M
The seemingly simple elastic scattering of protons still presents a challenge for the theory. In this thesis we discuss the elastic scattering from theoretical as well as experimental point of view. In the theory part, we present several models and their predictions for the LHC. We also discuss the Coulomb-hadronic interference, where we present a new eikonal calculation to all orders of alpha, the fine-structure constant. In the experimental part we introduce the TOTEM experiment which is dedicated, among other subjects, to the measurement of the elastic scattering at the LHC. This measurement is performed primarily with the Roman Pot (RP) detectors - movable beam-pipe insertions hundreds of meters from the interaction point, that can detect protons scattered to very small angles. We discuss some aspects of the RP simulation and reconstruction software. A central point is devoted to the techniques of RP alignment - determining the RP sensor positions relative to each other and to the beam. At the end we pres...
International Nuclear Information System (INIS)
Garcia, N.
1978-01-01
The GR method for solving the scattering equations of atoms from a hard corrugated surface is applied on accelerated particles above a hard corrugated surface and a hard corrugated surface with an attractive well. The solutions are given for the Rayleigh hypothesis that under the range of corrugation presented in this paper leads to the exact ones. Threshold resonances are studied observing that the appearance and disappearance of beams must be for a general theory with vertical tangent. The structure of the Lennard-Jones resonances given for the model mentioned above. For the first time it is stressed that Lennard-Jones resonances are not observed in metal surfaces in general, and, accordingly, they are unobserved in compact metallic surfaces. This is correlated with the fact that diffraction has not been observed. Both facts are due to the very weak corrugation of the gas-metal interaction potential. According to our results, the Lennard-Jones resonances in metals present greater difficulties to be observed experimentally. It is also noted that the absence of diffraction in compact metal surfaces is because they are almost plane and not because of the Debye-Waller effect. Finally, the lifetimes of the atoms at the crystal surfaces are calculated. These are larger, the smaller the incident energy and the larger the corrugation. But the lifetimes are particularly large at resonance conditions (10 -11 s). (Auth.)
Di Pietro, A; Fisichella, M; Alcorta, M; Borge, M J G; Davinson, T; Ferrera, F; Figuera, P; Laird, A M; Lattuada, M; Shotter, A C; Soic, N; Tengblad, O; Torresi, D; Zadro, M
2017-01-01
The excitation function of the resonant reaction 4He(9Li,α) was measured with the aim of investigating the compound nucleus 13B. These measurements were performed in inverse kinematics at center-of-mass scattering angles close to 180◦ by using a thick 4He gas target and a 9Li beam. The 13B excitation energy region explored was 14–20 MeV where 9Li–α configurations of 13B are predicted by Antysimmetrised Molecular Dynamics calculations. The measured excitation function at θcm = 180◦ shows different clear structures in a 13B excitation energy region which was experimentally unknown.
International Nuclear Information System (INIS)
Yuan, J.; Zhang, Z.
1993-01-01
Spin polarizations (SP's) of elastic electron scattering from alkaline-earth-metal atoms in Ramsauer-Townsend (RT) and low-lying shape resonance (SR) regions are calculated using a relativistic method. The detailed SP distributions both with scattering angle and with electron energy are presented via the energy- and angle-dependent surfaces of SP parameters. It is shown that the SP effects of the collisions of electrons with Ca, Sr, and Ba atoms in the RT region are significant in a considerable area on the energy-angle plane and that the spin-orbit interaction is well increased around the low-lying p-wave SR states of Be and Mg and the d-wave SR states of Ca, Sr, and Ba
Elastic and inelastic photon scattering on the atomic nuclei
International Nuclear Information System (INIS)
Piskarev, I.M.
1982-01-01
Works on investigation of elastic and inelastic scattering of photons on heavy and intermediate nuclei are briefly reviewed. Theoretical problems of nuclear and electron Tompson, Releev and Delbrueck scatterings as well as nuclear resonance scattering are briefly discussed. It is shown that differential cross section of coherent elastic scattering is expressed by means of partial amplitudes of shown processes. Experimental investigations on elastic scattering in the region of threshold energies of photonucleon reactions are described. Problems of theoretical description of elastic scattering in different variants of collective models are considered. Discussed are works, investigating channels of inelastic photon scattering with excitation of nuclear Raman effect. It is noted that to describe channels of inelastic photon scattering it is necessary to use models, that correctly regard the microscopic structure of giant resonance levels to obtain information on the nature of these levels. Investigations of processes of photon elastic and inelastic scattering connected with fundamental characteristics of atomic nucleus, permit to obtain valuable spectroscopic information on high-lying levels of nucleus. Detail investigation of photon scattering in a wide range of energies is necessary [ru
Heavy ion elastic scattering of code : OPTHI
International Nuclear Information System (INIS)
Ismail, M.; Divatia, A.S.
1982-01-01
A computer code, OPTHI has been designed to calculate nuclear optical model elastic cross sections for the scattering of heavy ions. The program has been designed to be utilitarian rather than capable of giving an exact description of elastic scattering. Input format is described and the program listing is given. (M.G.B.)
Tensor polarization in pion-deuteron elastic scattering
International Nuclear Information System (INIS)
Holt, R.J.; Freeman, W.S.; Geesaman, D.F.
1985-01-01
During this year the analysis of measurements of t 20 in π-d elastic scattering was completed and a final summary manuscript was prepared for publication. The results consists of angular distributions of the deuteron tensor polarization in π-d elastic scattering at pion energies of 140, 180, 220 and 256 MeV. Theoretical calculations in which the effects of pion absorption on the elastic channel are small reproduce the data. No rapid angular or energy dependence was found near a pion energy of 134 MeV, where another experiment at SIN has suggested the existence of dibaryon resonances
Photon scattering by the giant dipole resonance
International Nuclear Information System (INIS)
Bowles, T.J.; Holt, R.J.; Jackson, H.E.; McKeown, R.D.; Specht, J.R.
1979-01-01
Although many features of the giant dipole resonance are well known, the coupling between the basic dipole oscillation and other nuclear collective degrees of freedom such as surface vibrations and rotations is poorly understood. This aspect was investigated by elastic and inelastic bremsstrahlung scattering of tagged photons over the energy range 15 to 22 MeV. Target nuclei were 60 Ni, 52 Cr, 56 Fe, 92 Mo, and 96 Mo. Scattering and absorption cross sections are tabulated, along with parameters obtained from a two-Lorentzian analysis of the scattering cross sections; measured spectra are shown. It was necessary to remove Thomson scattering from the experimental results. It was found that coupling to surface vibrations in the giant dipole resonance is much weaker than the dynamic collective model suggests. The elastic scattering cross section for all targets but 60 Ni showed structure that is not evident in the absorption cross section measurement. 12 figures, 2 tables
Elastic scattering of low-energy electrons from ammonia
International Nuclear Information System (INIS)
Alle, D.T.; Gulley, R.J.; Buckman, S.J.; Brunger, M.J.
1992-01-01
We report absolute differential cross section measurements for vibrationally elastic electron scattering from NH 3 at incident energies from 2-30 eV. The present results, from a crossed electron-molecular beam apparatus, represent the first comprehensive experimental attempt to quantify the elastic electron-NH 3 scattering process. At each energy studied we have integrated our differential cross section data to generate total elastic and elastic momentum transfer cross sections and a critical comparison of both our differential and integral cross sections against previous experiment and theory is provided. We also report our observation of a strong Feshbach resonance in the elastic channel at an energy of 5.59 ± 0.05 eV. (Author)
Elastic scattering of slow positrons by helium
International Nuclear Information System (INIS)
Amusia, M.Ya.; Cherepkov, N.A.; Chernysheva, L.V.; Shapiro, S.G.
1976-01-01
The s-, p-, d- and f-wave phaseshifts for elastic scattering of slow positrons by He are calculated using a simplified version of the random phase approximation with exchange, with virtual positronium formation effect taken into account. (author)
Elastic and inelastic heavy ion scattering
International Nuclear Information System (INIS)
Toepffer, C.; University of the Witwatersrand, Johannesburg; Richter, A.
1977-02-01
In the field of elastic and inelastic heavy ion scattering, the following issues are dealt with: semiclassical descriptive approximations, optical potentials, barriers, critical radii and angular momenta, excitation functions and the application to superheavy ions and high energies. (WL) [de
Energy Technology Data Exchange (ETDEWEB)
Achouri, N.L
2001-09-01
This thesis describes two studies which explore the structure of proton-rich nuclei. The first of these concerned an investigation of the {beta}-delayed charged particle decay of {sup 22}Al. The experiment was carried out using the LISE3 spectrometer at GANIL and permitted the energies of the {beta}-p, {beta}-2p and {beta}-{alpha} transitions together with the corresponding branching ratios to be determined with an improved precision over earlier work. In addition the coincidences with {gamma}-rays were measured for the first time allowing the decay scheme to be reconstructed. Comparison with shell model calculations using the code OXBASH and the mirror nucleus {sup 22}F allowed the spin and parity and the mass of {sup 22}Al g.s. as well as levels in {sup 22}Mg to be deduced. The experimentally determined Gamow Teller strength was found to be in good agreement at low excitation energies with a shell model calcination employing an effective operator. The second study concerned the development of resonant elastic scattering in inverse kinematics as a spectroscopic tool. Extensive simulations were carried out to ascertain the feasibility of such experiments as well as to optimise the set-up. In the context of the later, particular attention was paid to the final resolution. Experiments subsequently undertaken at GANIL with stable and radioactive beams demonstrated that the technique will be a powerful spectroscopic tool for use with radioactive beams with characteristics similar to those that will be furnished by SPIRAL. (author)
Alekseev, I G; Beloglasov, Yu A; Budkovsky, P E; Bunyatova, E I; Kanavets, V P; Kovalev, A I; Koroleva, L I; Kruglov, S P; Morozov, B V; Nesterov, V M; Novinsky, D V; Ryltzov, V V; Shchedrov, V A; Sulimov, A D; Sumachev, Yu V; Svirida, D N; Trautman, V Yu; Zhurkin, V V
2001-01-01
The spin rotation parameters A and R were measured for the elastic pion-proton scattering by the PNPI-ITEP collaboration in the D/sub 13 /(1700) resonance region. The main goal of the experimental program is to resolve the current partial-wave analyses (PWA) uncertainties. Simultaneously with A and R the polarization parameter P was measured with the purpose to improve the experimental database and estimate systematic errors. The constraint which demands a smooth energy dependence of all pi /sup -/p transverse amplitude zeros in the complex plane together with the new experimental data on the A parameter can lead to the conclusion that the Barrelet branch of "zero trajectories" is chosen improperly in PWA of the Carnegie- Mellon-Lawrence-Berkeley-Laboratory groups at the range of the pion beam momentum near 1.0 GeV/c. The setup included a longitudinally polarized proton target with superconductive magnet, multiwire spark chambers and carbon polarimeter with thick filter. The experiment was performed at the IT...
On the K+-nucleus elastic scattering
International Nuclear Information System (INIS)
Ning, P.; Men, D.
1991-01-01
In this paper conventional and unconventional nuclear medium effects in the K + scattering are briefly reviewed. Microscopic calculations of the K + elastic scattering on 4 He, 12 C, 40 Ca, 120 Sn at 800 MeV/c are performed and then possible swellings of nucleons in nuclei are discussed
Directory of Open Access Journals (Sweden)
A. Donnachie
1984-01-01
Full Text Available We present an analysis of pp and ̄pp elastic scattering in terms of various exchanges. Three-gluon exchange dominates at large t, and single-pomeron exchange at small t. The dip seen in high-energy pp scattering is provided by the interference of both of these with double-pomeron exchange. We predict that this dip will not be found in high-energy ̄pp scattering. The dip that is seen in low-energy ̄pp scattering is the result of the additional presence of reggeon-pomeron exchange.
Resonantly scattering crystals and surfaces
International Nuclear Information System (INIS)
Gunn, J.M.F.; Mahon, P.J.
1990-12-01
We examine coherence effects from forming a crystal of resonant scatterers by generalising the Fano model for autoionising resonances in electron scattering from atoms to a lattice of such scatterers. (We have in mind the case of neutron scattering from nuclei.) We solve this problem to yield two branches to the dispersion relation for the neutron in general and three when the resonance coincides with a Brillouin Zone boundary. The 'width' of the resonance is enhanced over the isolated nucleus, the best candidate for observation being the 2eV 185 Re resonance near the Bragg condition. We use these results to calculate the reflection coefficient from a surface, revealing total external reflection near resonance. We discuss experimental feasibility in both the neutron and electron cases. (author)
pp elastic scattering at LHC energies
Energy Technology Data Exchange (ETDEWEB)
Kohara, A.K.; Ferreira, E.; Kodama, T. [Universidade Federal do Rio de Janeiro, Instituto de Fisica, C.P. 68528, Rio de Janeiro, RJ (Brazil)
2014-11-15
Using a unified analytic representation for the elastic scattering amplitudes of pp scattering valid for all energies above 20 GeV, the behavior of observables in the LHC collisions in the range √(s) = 2.76-14 TeV is discussed. After the precise description of dσ/dt at 7 TeV, we discuss the energy dependence of the amplitudes and expect that the proposed analytical forms give equally good predictions for the future experiments. (orig.)
pp elastic scattering at LHC energies
International Nuclear Information System (INIS)
Kohara, A.K.; Ferreira, E.; Kodama, T.
2014-01-01
Using a unified analytic representation for the elastic scattering amplitudes of pp scattering valid for all energies above 20 GeV, the behavior of observables in the LHC collisions in the range √(s) = 2.76-14 TeV is discussed. After the precise description of dσ/dt at 7 TeV, we discuss the energy dependence of the amplitudes and expect that the proposed analytical forms give equally good predictions for the future experiments. (orig.)
Diffraction dissociation and elastic scattering
International Nuclear Information System (INIS)
Verebryusov, V.S.; Ponomarev, L.A.; Smorodinskaya, N.Ya.
1987-01-01
In the framework of Regge scheme with supercritical pomeron a model is suggested for the NN-scattering amplitude which takes into account the contribution introduced to the intermediate state by diffraction dissociation (DD) processes. The DD amplitude is written in terms of the Deck model which has been previously applied to describing the main DD features. The calculated NN cross sections are compared with those obtained experimentally. Theoretical predictions for higher energy are presented
Elastic positron-cadmium scattering at low energies
International Nuclear Information System (INIS)
Bromley, M. W. J.; Mitroy, J.
2010-01-01
The elastic and annihilation cross sections for positron-cadmium scattering are reported up to the positronium-formation threshold (at 2.2 eV). The low-energy phase shifts for the elastic scattering of positrons from cadmium were derived from the bound and pseudostate energies of a very large basis configuration-interaction calculation of the e + -Cd system. The s-wave binding energy is estimated to be 126±42 meV, with a scattering length of A scat =(14.2±2.1)a 0 , while the threshold annihilation parameter, Z eff , was 93.9±26.5. The p-wave phase shift exhibits a weak shape resonance that results in a peak Z eff of 91±17 at a collision energy of about 490±50 meV.
Elastic proton-proton scattering at RHIC
Energy Technology Data Exchange (ETDEWEB)
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.
Elastic electron scattering at large momentum transfer
International Nuclear Information System (INIS)
Arnold, R.G.
1979-05-01
A review is given of elastic electron scattering at large momentum transfer (Q 2 > 20 fm -2 ) from nuclei with A less than or equal to 4. Recent experimental results are reviewed and the current problems in interpretation of these results are pointed out. Some questions for future experiments are posed, and a preview of possible future measurements is presented. 28 references
Elastic and inelastic electron and muon scattering
International Nuclear Information System (INIS)
Hand, L.N.
1977-01-01
The current status of experiments in the field of elastic and inelastic electron and muon scattering is discussed. The talk is divided into discussions of the single arm inclusive experiments at SLAC and Fermilab; the multiparticle inclusive experiments at SLAC, Fermilab und Cornell, and a description of selected results from exclusive channel measurements on electroproduced final states. (orig.) [de
Elastic scattering of low energy γ-rays
International Nuclear Information System (INIS)
Whittingham, I.B.
1978-05-01
Theoretical cross sections for the elastic scattering of 245, 334, 444, 779, 1086, 1112 and 1408 keV γ-rays by Pb are obtained for scattering angles up to 150 degrees. Three sets of Rayleigh scattering amplitudes have been computed using (1) the calculations of Johnson and Cheng, (2) the K shell calculations of Brown and co-workers supplemented by form factors amplitudes for higher shells, and (3) form factor amplitudes for all shells. Nuclear Thomson amplitudes have been included for all energies and, for 1408 keV, Delbruck scattering based upon the calculations of Papatzacos and Mork has been included. Nuclear resonance scattering is show to be negligble for all energies
Hadron elastic scattering at small angles
2002-01-01
This experiment is an extension of the measurements of the WA9 experiment up to the highest energies available in the North Area. It will measure the differential cross-section for hadron elastic scattering in the t-range 0.002-0.05 (GeV/c)$^{2}$ using an ionization chamber for the measurement of the energy and the angle of the recoil and a magnet-WC spectrometer to measure the momentum and direction of the forward particle. From these measurements will be obtained the ratio $\\rho$ of the real to imaginary parts of the forward elastic amplitude and the exponential slope parameter b of the hadronic amplitude at small t. The precision expected in these measurements is $\\Delta \\rho \\approx \\pm 0.01$ and $\\Delta$b $\\approx \\pm 0.2$ (GeV/c)$^{-2}$. \\\\ \\\\ The experimental programme includes: \\\\\\\\ i) measurements of $\\rho$ and b for $\\pi$p elastic scattering at incident momenta between 150 GeV/c and 300 GeV/c; \\\\ ii) measurements of $\\rho$ and b for $\\pi^{+}$p and pp elastic scattering at incident momenta between 5...
14O+p elastic scattering in a microscopic cluster model
International Nuclear Information System (INIS)
Descouvemont, P.; Baye, D.; Leo, F.
2006-01-01
The 14O+p elastic scattering is analyzed in a fully microscopic cluster model. With the Resonating Group Method associated with the microscopic R-matrix theory, phase shifts and cross sections are calculated. Data on 16O+p are used to test the precision of the model. For the 14O+p elastic scattering, an excellent agreement is found with recent experimental data. Resonances properties in 15F are discussed
Elastic scattering of low-energy electrons with Sr atoms
International Nuclear Information System (INIS)
Yuan, J.; Zhang, Z.; Wan, H.
1990-01-01
Static-exchange, plus correlation-polarization-potential calculations are performed for elastic low-energy electron scattering from Sr atoms while paying attention to the low-lying shape resonances. The correlation potential is calculated both with and without a scaling factor. A 2 D-shape resonance is produced at 1.0 eV with a parameter-free, and at 1.25 eV with a scaled, correlation potential. No 2 P-shape resonances are predicted, but evidence to support the existence of a stable negative ion Sr - in the 5s 2 5p electron configuration is given from the viewpoint of electron scattering. The bound energy of the extra electron in the negative ion is estimated by transforming the phase shift of the corresponding partial wave into the polarization quantum-defect number and extrapolating the number from positive to negative energies
Inelastic scattering in resonant tunneling
DEFF Research Database (Denmark)
Wingreen, Ned S.; Jacobsen, Karsten Wedel; Wilkins, John W.
1989-01-01
The exact resonant-tunneling transmission probability for an electron interacting with phonons is presented in the limit that the elastic coupling to the leads is independent of energy. The phonons produce transmission sidebands but do not affect the integrated transmission probability or the esc......The exact resonant-tunneling transmission probability for an electron interacting with phonons is presented in the limit that the elastic coupling to the leads is independent of energy. The phonons produce transmission sidebands but do not affect the integrated transmission probability...
International Nuclear Information System (INIS)
Matthews, S.K.
1993-11-01
Several experiments have measured nominally-charge-symmetric scattering of pions from tritium ( 3 H) and 3 He. These experiments have covered incident pion energies from 142 MeV to 295 MeV and scattering angles up to 110 degrees in the laboratory. The results have been used to study charge-symmetry breaking and nuclear scattering systematics. In the work I have extended these measurements to angles near 180 degrees for pion energies of 142 MeV, 180 MeV, 220 MeV, and 256 MeV, which bracket the Δ 33 pion-nucleon resonance. This is the most extensive set of πT and π 3 He data in this kinematical region. It will allow tests of scattering theory of pion-nucleus interactions and charge-symmetry breaking in back-angle scattering, and, within the limits of these two theories, it may help improve our understanding of the structure of these nuclei
ELASTIC SCATTERING: How goes the Odderon?
International Nuclear Information System (INIS)
Fried, H.M.; Kang, Kyungsik; Tan, C-I
1994-01-01
Spurred by new measurements of total reaction rates and associated parameters by groups at CERN, DESY, and Fermilab, and with the scent of possible solutions to past controversies in the air, some 110 experimental and theoretical highenergy physicists gathered at Brown University (Providence, Rhode Island) for the fifth traditional 'Blois' Workshop on High-Energy Elastic and Diffractive Scattering. Very much alive is the 'Odderon' - the extra effect to explain the difference between proton-proton and proton-antiproton scattering.
Resonant x-ray Raman scattering from atoms and molecules
International Nuclear Information System (INIS)
Cowan, P.L.
1992-01-01
Inelastic x-ray scattering and elastic x-ray scattering are fundamentally related processes. When the x-ray photon energy is near the ionization threshold for an inner shell, the inelastic channel is dominated by resonant x-ray Raman scattering. Studies of this emission not only illuminate the resonant scattering process in general, they also point to new opportunities for spectral studies of electronic structure using x-rays. Atoms in the form of a free gas provide an ideal target for testing the current theoretical understanding of resonant x-ray Raman scattering. In addition, x-ray scattering from molecular gases demonstrates the effect of bonding symmetry on the polarization and angular distribution of the scattered x-rays. Comparisons of experimental data with theory demonstrate both the successes and limitations of simple, single-electron interpretations of the scattering process
Elastic scattering of gamma radiation in solids
International Nuclear Information System (INIS)
Goncalves, O.D.
1987-01-01
The elastic scattering of gamma rays in solids is studied: Rayleigh scattering as well as Bragg scattering in Laue geometries. We measured Rayleigh cross sections for U, Pb, Pt, W, Sn, Ag, Mo, Cd, Zn, and Cu with gamma energies ranging from 60 to 660 KeV and angles between 5 0 and 140 0 . The experimental data are compared with form factor theories and second order perturbation theories and the limits of validity of both are established. In the 60 KeV experiment, a competition between Rayleigh and Bragg effects is found in the region of low momentum transfer. The Bragg experiments were performed using the gamma ray diffractometer from the Hahn-Meitner Institut (Berlin) with gammas of 317 KeV and angles up to 2 0 . In particular, we studied the effect of annealing in nearly perfect Czochralski Silicon crystals with high perfection in the crystallographic structure. The results are compared with Kinematical and Dynamical theories. (author)
New focus for elastic and diffractive scattering
International Nuclear Information System (INIS)
Kwiecinski, J.
1995-01-01
A regular feature of the international physics calendar is the International Conference on Elastic and Diffractive Scattering, known also as the Blois Workshops, after their 1985 birthplace in France. The content of this year's meeting embraced a broad spectrum of problems ranging from the classical analysis of elastic scattering and total cross-sections to the ''hard'' or deep inelastic phenomena which test the underlying quark-gluon structure of hadrons. These meetings have traditionally concentrated on broad questions of elastic and diffractive scattering, however the shift of emphasis in physics is now reflected at Blois by interest in the wide range of 'soft' hadronic processes which dominate reaction cross-sections. On the traditional side, a substantial part of the conference was devoted to analysis of forward scattering parameters like total cross-sections, real parts etc, using dispersion relations and fundamental asymptotic theorems which bound the possible growth of those parameters with energy. The present experimental situation in this field was summarized by S. Pruss, followed by theoretical presentations by B. Nicolescu, A. Donnachie, T.T. Wu, A. Martin and others. The data for proton-proton and proton-antiproton scattering seem to support dominance of the 'crossing-even' part of the scattering amplitude (which contributes equally to both proton-proton and protonantiproton scattering), with little evidence for a substantial 'odderon' term which contributes with opposite sign in the two cases. The 'pomeron' physics of high energy behaviour was a central feature of the conference. The experimental data seem to suggest that behaviour with increasing energy depends on the magnitude of the scale which characterizes the process - i.e. whether the process is ''soft'' or ''hard''. Hard processes, in general, show a much more rapid increase with increasing
Elastic wave scattering methods: assessments and suggestions
International Nuclear Information System (INIS)
Gubernatis, J.E.
1985-01-01
The author was asked by the meeting organizers to review and assess the developments over the past ten or so years in elastic wave scattering methods and to suggest areas of future research opportunities. He highlights the developments, focusing on what he feels were distinct steps forward in our theoretical understanding of how elastic waves interact with flaws. For references and illustrative figures, he decided to use as his principal source the proceedings of the various annual Reviews of Progress in Quantitative Nondestructive Evaluation (NDE). These meetings have been the main forum not only for presenting results of theoretical research but also for demonstrating the relevance of the theoretical research for the design and interpretation of experiment. In his opinion a quantitative NDE is possible only if this relevance exists, and his major objective is to discuss and illustrate the degree to which relevance has developed
Resonance scattering of Rayleigh waves by a mass defect
International Nuclear Information System (INIS)
Croitoru, M.; Grecu, D.
1978-06-01
The resonance scattering of an incident Rayleigh wave by a mass defect extending over a small cylindrical region situated in the surface of a semi-infinite isotropic, elastic medium is investigated by means of the Green's function method. The form of the differential cross-section for the scattering into different channels exhibits a strong resonance phenomenon at two frequencies. The expression of the resonance frequencies as well as of the corresponding widths depends on the relative change in mass density. The main assumption that the wavelengths of incoming and scattered wave are large compared to the defect dimension implies a large relative mass-density change. (author)
Resonant Impulsive Stimulated Raman Scattering
Energy Technology Data Exchange (ETDEWEB)
Mokhtari, A; Chesnoy, J
1988-03-15
Using a femtosecond dye laser, we observe in real-time vibrational oscillations excited by impulsive stimulated Raman scattering (ISRS) close to an electronic resonance. We perform single-beam Raman excitation and probe the driven coherence by a polarization-sensitive detection. We demonstrate for the first time impulsively Raman-induced dichroism, birefringence as well as frequency and time delay shifts. We analyse the characteristics of resonant ISRS on a vibrational mode of a dye molecule (malachite green) in solution.
Resonant Impulsive Stimulated Raman Scattering
International Nuclear Information System (INIS)
Mokhtari, A.; Chesnoy, J.
1988-01-01
Using a femtosecond dye laser, we observe in real-time vibrational oscillations excited by impulsive stimulated Raman scattering (ISRS) close to an electronic resonance. We perform single-beam Raman excitation and probe the driven coherence by a polarization-sensitive detection. We demonstrate for the first time impulsively Raman-induced dichroism, birefringence as well as frequency and time delay shifts. We analyse the characteristics of resonant ISRS on a vibrational mode of a dye molecule (malachite green) in solution
Elastic Scattering - Past, Present and Future
International Nuclear Information System (INIS)
Fazal-e-Aleem; Rashid, Haris; Tahir, Sohail Afzal
2007-01-01
Various aspects of elastic and diffractive scattering have been studied at Fermilab and CERN. Search for more results is ongoing at RHIC and planned at LHC. In this talk, we review the progress made so far and elaborate future prospects. Theoretical study focuses on the analysis of the available data in the light of predictions of various models with special emphasis on Eikonal picture and QCD inspired models. In the light of this analysis, various possibilities have been explored with reference to RHIC and LHC measurements
Elastic hadron scattering and optical theorem
Lokajicek, Milos V.; Prochazka, Jiri
2014-01-01
In principle all contemporary phenomenological models of elastic hadronic scattering have been based on the assumption of optical theorem validity that has been overtaken from optics. It will be shown that the given theorem which has not been actually proved cannot be applied to short-ranged strong interactions in any case. The actual progress in description of collision processes might then exist only if the initial states are specified on the basis of impact parameter values of colliding particles and probability dependence on this parameter is established.
Quasi-Elastic Light Scattering in Ophthalmology
Ansari, Rafat R.
The eye is not just a "window to the soul"; it can also be a "window to the human body." The eye is built like a camera. Light which travels from the cornea to the retina traverses through tissues that are representative of nearly every tissue type and fluid type in the human body. Therefore, it is possible to diagnose ocular and systemic diseases through the eye. Quasi-elastic light scattering (QELS) also known as dynamic light scattering (DLS) is a laboratory technique routinely used in the characterization of macromolecular dispersions. QELS instrumentation has now become more compact, sensitive, flexible, and easy to use. These developments have made QELS/DLS an important tool in ophthalmic research where disease can be detected early and noninvasively before the clinical symptoms appear.
Scattering of elastic waves by thin inclusions
International Nuclear Information System (INIS)
Simons, D.A.
1980-01-01
A solution is derived for the elastic waves scattered by a thin inclusion. The solution is asymptotically valid as inclusion thickness tends to zero with the other dimensions and the frequency fixed. The method entails first approximating the total field in the inclusion in terms of the incident wave by enforcing the appropriate continuity conditions on traction and displacement across the interface, then using these displacements and strains in the volume integral that gives the scattered field. Expressions are derived for the far-field angular distributions of P and S waves due to an incident plane P wave, and plots are given for normalized differential cross sections of an oblate spheroidal tungsten carbide inclusion in a titanium matrix
Gluon exchange in elastic hadron scattering
International Nuclear Information System (INIS)
Jenkovszky, L.L.; Paccanoni, F.; Chikovani, Z.E.
1991-01-01
It is generally accepted that the Pomeron, which determines the long-range component of the strong interaction, corresponds to exchange of gluons with the corresponding quantum numbers (the minimum number of such gluons is two). The C-odd partner of the Pomeron, the odderon, corresponds to exchange of an odd number of gluons (three or more). By means of a model of the nonperturbative gluon propagator, restrictions are obtained on the parameters of two-gluon (Pomeron) and three-gluon (odderon) exchange in hadron scattering. In the framework of this model an interpretation is proposed for the various asymptotic regimes in the behavior of the total cross section and of the differential cross section of elastic scattering at high energies
Nonlinear elasticity in resonance experiments
Li, Xun; Sens-Schönfelder, Christoph; Snieder, Roel
2018-04-01
Resonant bar experiments have revealed that dynamic deformation induces nonlinearity in rocks. These experiments produce resonance curves that represent the response amplitude as a function of the driving frequency. We propose a model to reproduce the resonance curves with observed features that include (a) the log-time recovery of the resonant frequency after the deformation ends (slow dynamics), (b) the asymmetry in the direction of the driving frequency, (c) the difference between resonance curves with the driving frequency that is swept upward and downward, and (d) the presence of a "cliff" segment to the left of the resonant peak under the condition of strong nonlinearity. The model is based on a feedback cycle where the effect of softening (nonlinearity) feeds back to the deformation. This model provides a unified interpretation of both the nonlinearity and slow dynamics in resonance experiments. We further show that the asymmetry of the resonance curve is caused by the softening, which is documented by the decrease of the resonant frequency during the deformation; the cliff segment of the resonance curve is linked to a bifurcation that involves a steep change of the response amplitude when the driving frequency is changed. With weak nonlinearity, the difference between the upward- and downward-sweeping curves depends on slow dynamics; a sufficiently slow frequency sweep eliminates this up-down difference. With strong nonlinearity, the up-down difference results from both the slow dynamics and bifurcation; however, the presence of the bifurcation maintains the respective part of the up-down difference, regardless of the sweep rate.
Nuclear magnetic resonance scattering
International Nuclear Information System (INIS)
Young, I.R.
1985-01-01
A nuclear magnetic resonance apparatus is described including a magnet system which is capable of providing a steady magnetic field along an axis, and is constructed so as to define a plurality of regions along the axis in each of which the field is substantially homogeneous so that in each region an imaging operation may be separately carried out. Iron shields increase the field homogeneity. In use, each patient lies on a wheeled trolley which is provided with magnetic field gradient coils and an RF coil system, some of the coils being movable to facilitate positioning of the patient, and there are terminals for connection to a common computing and control facility. (author)
Elastic electron scattering from the DNA bases: cytosine and thymine
International Nuclear Information System (INIS)
Colyer, C J; Bellm, S M; Lohmanny, B; Blanco, F; Garcia, G
2012-01-01
Relative elastic differential cross sections for elastic scattering from cytosine and thymine have been measured using the crossed beam method. The experimental data are compared with theoretical cross sections calculated by the screen corrected additivity rule method.
Pion-nucleus scattering around the (3,3) resonance
International Nuclear Information System (INIS)
Rahman, M.A.; Sen Gupta, H.M.; Rahman, M.
1989-09-01
Elastic scattering of π ± are studied on 28 Si, 40 Ar, 40,48 Ca, 90 Zr and 208 Pb at energies around the (3,3) resonance within the framework of the strong absorption model of Frahn and Venter. The parameters thus obtained are used in the analysis of the inelastic scattering of pions leading to the lowest 2 ± state in 28 Si. A reasonably good account of the scattering processes (elastic and inelastic) is given by the simple model. (author). 13 refs, 8 figs, 3 tabs
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 ...
Folding models for elastic and inelastic scattering
International Nuclear Information System (INIS)
Satchler, G.R.
1982-01-01
The most widely used models are the optical model potential (OMP) for elastic scattering, and its generalization to non-spherical shapes, the deformed optical model potential (DOMP) for inelastic scattering. These models are simple and phenomenological; their parameters are adjusted so as to reproduce empirical data. Nonetheless, there are certain, not always well-defined, constraints to be imposed. The potential shapes and their parameter values must be reasonable and should vary in a smooth and systematic way with the masses of the colliding nuclei and their energy. One way of satisfying these constraints, without going back to a much more fundamental theory, is through the use of folding models. The basic justification for using potentials of the Woods-Saxon shape for nucleon-nucleus scattering, for example, is our knowledge that a nuclear density distribution is more-or-less constant in the nuclear interior with a diffuse surface. When this is folded with a short-range nucleon-nucleon interaction, the result is a similar shape with a more diffuse surface. Folding procedures allow us to incorporate many aspects of nuclear structure (although the nuclear size is one of the most important), as well as theoretical ideas about the effective interaction of two nucleons within nuclear matter. It also provides us with a means of linking information obtained from nuclear (hadronic) interactions with that from other sources, as well as correlating that from the use of different hadronic probes. Folding model potentials, single-folded potentials, and the double-folding model including applications to heavy-ion scattering are discussed
Forward elastic scattering above the physical threshold
Energy Technology Data Exchange (ETDEWEB)
Avila, R.F. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Matematica, Estatistica e Computacao Cientifica; Menon, M.J. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Fisica Gleb Wataghin
2006-07-01
Making use of the 'extended derivative dispersion relations', recently introduced by Avila and Menon, we analyze forward elastic proton-proton and antiproton-proton scattering at any energy above the physical threshold ({radical}s=2m{sub p} {approx} 1,88 GeV). The analysis is based on an analytical parametrization for the total cross section with leading triple pole pomeron (high energies) and full nondegenerated secondary reggeons (intermediate and low energies). Experimental data on total cross section and the ratio r between the real and imaginary parts of the forward amplitude are simultaneously fitted with the CERN-Minuit code and energy cutoff at 4 GeV. We show that, the results are exactly the same as those obtained through standard integral dispersion relations. Physical implications of the results in the pomeron-reggeon context are also discussed. (author)
Elastic scattering at the collider and beyond
International Nuclear Information System (INIS)
Henzi, R.
1985-01-01
Not only in hard but also in soft collisions have new, very interesting and somewhat puzzling phenomena been discovered, especially in total cross sections and connected with it in elastic scattering by the UA4 Collaboration at the CERN Collider. It has turned out that Dispersive Diffraction Theory (DDT) is quite useful for the theoretical analysis of such phenomena, especially if one has in mind to make predictions for what will happen at the future colliders. In this paper new results of DDT are presented, among them: the use of black spots to discuss saturation mechanisms for the Froissart-Martin bound; the possible emergence of Martin scaling; a missing link between geometric scaling and factorizing eikonal; the real part and the associated dip-shoulder dynamics; and the nature of the change of slope at low momentum transfer
Singularities of elastic scattering amplitude by long-range potentials
International Nuclear Information System (INIS)
Kvitsinsky, A.A.; Komarov, I.V.; Merkuriev, S.P.
1982-01-01
The angular peculiarities and the zero energy singularities of the elastic scattering amplitude by a long-range potential are described. The singularities of the elastic (2 → 2) scattering amplitude for a system of three Coulomb particles are considered [ru
Support minimized inversion of acoustic and elastic wave scattering
International Nuclear Information System (INIS)
Safaeinili, A.
1994-01-01
This report discusses the following topics on support minimized inversion of acoustic and elastic wave scattering: Minimum support inversion; forward modelling of elastodynamic wave scattering; minimum support linearized acoustic inversion; support minimized nonlinear acoustic inversion without absolute phase; and support minimized nonlinear elastic inversion
Anisotropy function for pion-proton elastic scattering
Energy Technology Data Exchange (ETDEWEB)
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.
Proton-proton elastic scattering at ultrahigh energies
Energy Technology Data Exchange (ETDEWEB)
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 proton-proton elastic scattering
Energy Technology Data Exchange (ETDEWEB)
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).
Anisotropy function for proton-proton elastic scattering
International Nuclear Information System (INIS)
Saleem, Mohammad; Fazal-e-Aleem; Azhar, I.A.
1990-01-01
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→pp. (author)
Anisotropy function for pion-proton elastic scattering
International Nuclear Information System (INIS)
Saleem, Mohammad; Fazal-e-Aleem; Rashid, Haris
1988-01-01
By using the generalised Chou-Yang model and the experimental data on π - p elastic scattering at 200 GeV/c, the anisotropy function which reflects the non-isotropic nature of elastic scattering is computed for the reaction π - p → π - p. (author)
International Nuclear Information System (INIS)
Bystricky, J.; Deregel, J.; Lehar, F.
1984-01-01
The ratio of the analysing powers for quasi-elastic pp scattering in carbon and for elastic scattering on free protons was measured from T = 0.52 to 2.8 GeV by scattering of the SATURNE II polarized proton beam on carbon and CH 2 . It was found to have a maximum at about 0.8 GeV. The energy dependence for quasi-elastic scattering on carbon had not been measured before above 1 GeV. The observed effect was not expected from simple models
Hadron scattering, resonances, and QCD
Briceño, R. A.
2016-11-01
The non-perturbative nature of quantum chromodynamics (QCD) has historically left a gap in our understanding of the connection between the fundamental theory of the strong interactions and the rich structure of experimentally observed phenomena. For the simplest properties of stable hadrons, this is now circumvented with the use of lattice QCD (LQCD). In this talk I discuss a path towards a rigorous determination of few-hadron observables from LQCD. I illustrate the power of the methodology by presenting recently determined scattering amplitudes in the light-meson sector and their resonance content.
Resonant inelastic scattering of quasifree electrons on ions
International Nuclear Information System (INIS)
Grabbe, S.
1994-01-01
Several studies of resonant-transfer excitation (RTE) have been reported in ion-atom collisions where the doubly excited autoionizing states are produced. Such a complex collision can be approximated as the scattering of quasifree electrons of the target from the projectile ion. Most of the investigations have been restricted to the deexcitation of the autoionizing states to the ground state by Auger electron emission. It has been shown that there is a strong interference between the elastic scattering amplitude and the resonance amplitude. The authors present here the cases where the corresponding interference is between the inelastic scattering and the resonance process. Recent work on 3 ell 3 ell ' resonances that decay predominantly to n=2 states will be presented for C 5+ -molecular hydrogen collisions
Elastic scattering of 12C by 28Si
International Nuclear Information System (INIS)
Cheng, C.M.; Maher, J.V.; Chiou, M.S.; Jordan, W.J.; Peng, J.C.; Oelert, W.; Gunn, G.D.; Snyder, F.D.
1979-01-01
12 C + 28 Si elastic scattering angular distributions have been measured at twenty-three bombarding energies over a range 19 MeV 0 in the bombarding energy range 30--40 MeV. No optical potential has been found to give a good account of all the data; the best potential is a surface transparent Woods-Saxon potential which has energy dependences for both real and imaginary well depths. Examination of potentials which give reasonably good fits to the 36 MeV data shows that, although these potentials agree on a real well depth at a reasonable ''strong absorption radius,'' they can have quite different Argand diagrams: even in the range of the most sensitive partial waves. A Regge analysis finds several equally good families of Regge parameters for the same choice of background potential, but larger angle data might allow this ambiguity to be lifted. A Breit-Wigner analysis gives results which are at least partially consistent with the resonance parameters reported by Ost et al. Coupled-channel calculations with a 20% reduction of real and imaginary optical model well depths give a good account of inelastic scattering to the 28 Si 2 + state while leaving the elastic scattering essentially unchanged from the predictions of the unmodified one-channel optical model. In the energy range of this study the grazing partial wave is found to be the same as the most important exit channel partial wave of the 24 Mg( 16 O, 12 C) 28 Si ground state transition
Coupled channels effects in heavy ion elastic scattering
International Nuclear Information System (INIS)
Bond, P.D.
1977-01-01
The effects of inelastic excitation on the elastic scattering of heavy ions are considered within a coupled channels framework. Both Coulomb and nuclear excitation results are applied to 18 O + 184 W and other heavy ion reactions
Forward elastic scattering of electrons by hydrogen atoms
Energy Technology Data Exchange (ETDEWEB)
Garibotti, C.R. (Instituto de Fisica Teorica, R. Pamplona 145, Sao Paulo (Brazil)); Massaro, P.A. (Bari Univ. (Italy). Ist. di Fisica)
1978-01-11
The available theoretical and experimental values for the elastic, inelastic and ionization cross-sections of electrons by hydrogen atoms are used to obtain the total cross-section. The optical theorem and a dispersion relation are used to calculate the forward e-H scattering amplitude for medium and high energies. Using this quantity the reliability of the Born expansion for elastic e-H scattering is tested.
Uniqueness in inverse elastic scattering with finitely many incident waves
International Nuclear Information System (INIS)
Elschner, Johannes; Yamamoto, Masahiro
2009-01-01
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.)
Paneta, V.; Kokkoris, M.; Lagoyannis, A.; Preketes-Sigalas, K.
2017-09-01
The present work aims at contributing to the field of Ion Beam Analysis by providing a set of standard, high-accuracy nuclear resonance reaction data points to be used for accelerator energy calibration up to 4.6 MeV, more specifically with the use of the 27Al(p,γ), 13C(p,γ), 12C(p,p0) and 32S(p,p‧γ) resonant reactions, as a result of a comprehensive investigation in two different laboratories. The use of resonances at higher energies, namely up to 6 MeV, is also discussed. The measurements have been performed at two different electrostatic accelerators, namely at the 5.5 MV HV TN-11 of NCSR "Demokritos", Greece, and at the 5 MV 15SDH-2 Pelletron Tandem accelerator at Uppsala University in Uppsala, Sweden. Common points were used to normalize and validate the data. The possible use of the 16O(p,p0) resonance at 3.47 MeV is also discussed and analyzed.
Quasi-elastic shadowing in nucleus-nucleus elastic scattering
Energy Technology Data Exchange (ETDEWEB)
Dymarz, R; Malecki, A [Institute of Nuclear Physics, Krakow (Poland); Gluski, K [Institute of Nuclear Research, Warsaw (Poland); Picchi, P [Turin Univ. (Italy). Ist. di Fisica; Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica)
1979-01-06
The complete evaluation of the Glauber multiple-scattering series for nucleus-nucleus collisions is a very difficult task and that is why various approximate formulae were proposed. In this work some of these approximations are discussed.
Resonance interaction of heavy ions in radar scattering
International Nuclear Information System (INIS)
Strutinskij, V.M.
1983-01-01
Resonances on back angles in the process of scatterina of heavy ions are investigated. Comprehensive investigation into possible sources of irregular structure of angular distribution during elastic scattering (ES) on wide angles are compated with an experiment. The first source is a two-component interference and the second one is a resonance structure connected with the process of formation of definite nucleon states in strongly deformed intermediate nucleus. Comparison of radar cross section calculations (back scattering cross section) with angular ES distributions of hydrogen on silicon testifies a possibility to interpret an anomalous scattering on wide angles in some reactions with heavy ions as a result of modulation of partial amplitudes by resonances of the input state typein the initial state of interaction of two nuclei
Alignment creation by elastic electron scattering. A quantum treatment
International Nuclear Information System (INIS)
Csanak, G.; Kilcrease, D.P.; Fursa, D.V.; Bray, I.
2004-01-01
Alignment creation by elastic heavy particle scattering has been studied by many authors. A formula for the alignment creation cross section by elastic scattering is obtained by quantum-mechanical methods. The formula obtained differs from the analogous formula relevant for inelastic electron scattering. In the case of a J=1 to J=1 transition according to the inelastic formula, the alignment created is proportional to the quantity σ (1) - σ (0) where σ (M) is the excitation cross section of the M magnetic sublevel and thus σ (1) = (σ 1-1 + σ 10 + σ 11 )/3 and σ (0) = (σ 0-1 +σ 00 + σ 01 )/3 where σ MM' refers to the cross section of the electron impact induced M' to M transition. In the elastic scattering alignment creation formula obtained in the case of a J=1 to J=1 elastic scattering, the alignment created is proportional to the quantity q(1) - q(0) where q(1) σ (1) - σ 11 /3 and q(0) = σ 00 /3. Thus in obtaining q(M), the elastic scattering cross section by the M magnetic sublevel, σ MM' , is subtracted. This derivation considered only direct scattering, i.e. the incident electron was considered distinguishable from the target electrons. (Y.Kazumata)
Systematic study on nuclear resonant scattering
International Nuclear Information System (INIS)
Suarez, A.A.; Freitas, M.L.
1974-01-01
New resonant scattering effect of thermal neutron capture gamma rays from Ti and Fe on Sb, Cu, Se and Ce target were observed. These results together with those published by other authors are summarized and discussed in terms of a possible systematic search for new resonant scattering effects
Elastic scattering with the MINERνA experiment
International Nuclear Information System (INIS)
Ziemer, Benjamin P
2013-01-01
The Main Injector Experiment ν-A (MINERνA) located at Fermi National Laboratory will measure neutrino cross sections, nuclear effects from a broad range of nuclear targets and a variety of other neutrino interactions. Neutrino elastic scattering will be one of the first focuses of the MINERA collaboration; these measurements will be an important input to current and future neutrino oscillation experiments. Results of the charged current quasi-elastic channel exposure in anti-neutrino NuMI running are presented. Future elastic scattering results, both charged current and neutral current, in anti-neutrino and neutrino exposures are also discussed.
Do we understand elastic scattering up to LHC energies?
International Nuclear Information System (INIS)
Soffer, Jacques
2013-01-01
The measurements of high energy (bar sign)pp and pp elastic at ISR, SPS, and Tevatron colliders have provided usefull informations on the behavior of the scattering amplitude. A large step in energy domain is accomplished with the LHC collider presently running, giving a unique opportunity to improve our knowledge on the asymptotic regime of the elastic scattering amplitude and to verify the validity of our theoretical approach, to describe the total cross section σ tot (s), the total elastic cross section σ el (s), the ratio of the real to imaginary parts of the forward amplitude ρ(s) and the differential cross section dσ (s,t)/dt.
Elastic ππ scattering to two loops
International Nuclear Information System (INIS)
Bijnens, J.; Colangelo, G.; Gasser, J.; Ecker, G.; Sainio, M.E.
1995-11-01
We evaluate analytically the elastic ππ scattering amplitude to two loops in chiral perturbation theory and give numerical values for the two S-wave scattering lengths and for the phase shift difference δ 0 0 -δ 1 1 . (author)
Elastic scattering of low energy γ-rays
International Nuclear Information System (INIS)
Whittingham, I.B.
1978-01-01
The current status of the theory of the elastic scattering of low energy γ rays is reviewed and a detailed analysis of the theoretical background to the recent calculation of Rayleigh scattering by W.R.Johnson and co-workers is presented
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.
Elastic scattering of positronium: Application of the confined variational method
Zhang, Junyi; Yan, Zong-Chao; Schwingenschlö gl, Udo
2012-01-01
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
International Nuclear Information System (INIS)
Fazal-e-Aleem; Ali, S.
1991-01-01
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 √s = 53 GeV in the diffraction peak region. In order to fit the large momentum transfer data, the generalized Chou-Yang model is used
Fast Neutron Elastic and Inelastic Scattering of Vanadium
Energy Technology Data Exchange (ETDEWEB)
Holmqvist, B; Johansson, S G; Lodin, G; Wiedling, T
1969-11-15
Fast neutron scattering interactions with vanadium were studied using time-of-flight techniques at several energies in the interval 1.5 to 8.1 MeV. The experimental differential elastic scattering cross sections have been fitted to optical model calculations and the inelastic scattering cross sections have been compared with Hauser-Feshbach calculations, corrected for the fluctuation of compound-nuclear level widths.
Asymptotic perturbative QCD in elastic scattering, color transparency and ANN
International Nuclear Information System (INIS)
Botts, J.
1989-01-01
Sorting out the various perturbative contributions to wide angel elastic hadron-hadron scattering has been the subject of recent enquiry. Distinguishing the various contributions are the transverse size of the external hadrons and the interaction region and restrictions on the internal momenta flows. For wide angle elastic hadron-hadron scattering, the interaction between two types of perturbative processes, multiple and single scattering, can be the source of interference phenomena and interesting physics. In the following, after a brief description of the leading and non-leading processes, we shall give a picture of what perturbative QCD may have to say about elastic scattering, color transparency and the spin asymmetry, A NN . 9 refs., 5 figs
Fast elastic e-H(2s) scattering in laser fields
International Nuclear Information System (INIS)
Vucic, S.; Hewitt, R.; Hewitt, R.
1997-01-01
A numerical method for the evaluation of the Born endash Floquet amplitude for laser-assisted scattering is proposed for the case when a large basis set is required to achieve convergence. The method is applied to analyze the elastic scattering of fast electrons by the H(2s) state in a low-intensity laser field of varying frequency and to study the resonant scattering with increasing laser intensity. While the behavior of an atom in a resonant field of low intensity is determined by virtual transitions between resonant levels, at high intensity a great number of nonresonant virtual transitions may significantly influence laser-assisted processes. As a consequence, the attenuation of resonant effects could appear, as well as the open-quotes localclose quotes stabilization of the atom against ionization. copyright 1997 The American Physical Society
Quasi-elastic Neutrino Scattering - an Overview
International Nuclear Information System (INIS)
Sobczyk, Jan T.
2011-01-01
A non-technical overview of charge current quasi-elastic neutrino interaction is presented. Many body computations of multinucleon ejection which is proposed to explain recent large axial mass measurements are discussed. A few comments on recent experimental results reported at NuInt11 workshop are included.
Robust parameterization of elastic and absorptive electron atomic scattering factors
International Nuclear Information System (INIS)
Peng, L.M.; Ren, G.; Dudarev, S.L.; Whelan, M.J.
1996-01-01
A robust algorithm and computer program have been developed for the parameterization of elastic and absorptive electron atomic scattering factors. The algorithm is based on a combined modified simulated-annealing and least-squares method, and the computer program works well for fitting both elastic and absorptive atomic scattering factors with five Gaussians. As an application of this program, the elastic electron atomic scattering factors have been parameterized for all neutral atoms and for s up to 6 A -1 . Error analysis shows that the present results are considerably more accurate than the previous analytical fits in terms of the mean square value of the deviation between the numerical and fitted scattering factors. Parameterization for absorptive atomic scattering factors has been made for 17 important materials with the zinc blende structure over the temperature range 1 to 1000 K, where appropriate, and for temperature ranges for which accurate Debye-Waller factors are available. For other materials, the parameterization of the absorptive electron atomic scattering factors can be made using the program by supplying the atomic number of the element, the Debye-Waller factor and the acceleration voltage. For ions or when more accurate numerical results for neutral atoms are available, the program can read in the numerical values of the elastic scattering factors and return the parameters for both the elastic and absorptive scattering factors. The computer routines developed have been tested both on computer workstations and desktop PC computers, and will be made freely available via electronic mail or on floppy disk upon request. (orig.)
Exchange interpretation of anomalous back angle heavy ion elastic scattering
International Nuclear Information System (INIS)
Zisman, M.S.
1977-10-01
Anomalous back angle oscillations in the angular distributions obtained in the elastic scattering of 16 O + 28 Si and 12 C + 28 Si have been interpreted in terms of an elastic cluster transfer comparable to that observed in other heavy ion reactions. The calculations appear to at least qualitatively explain the data with respect to the existence and phase of the back angle oscillations. The results indicate that an exchange mechanism may play an important role in the oscillations
Microscopic investigations of the backward angle anomaly in elastic α-40Ca scattering
International Nuclear Information System (INIS)
Langanke, K.; Frekers, D.
1978-01-01
Elastic α-scattering on 40 Ca is studied microscopically by the resonating group method (RGM). Absorption effects are simulated by an imaginary potential whose spatial structure is taken to be proportional to the RGM overlap exchange kernel. The experimentally well-known backward anomaly is reproduced by the calculated angular distributions, and a clear connection between the Psub(l) 2 structures at backward angles and l-phase-shift resonances is shown. In this context the consistency of various methods of defining resonances in the presence of absorption is investigated. (Auth.)
Angular dispersion and deflection function for heavy ion elastic scattering
International Nuclear Information System (INIS)
Bai Zhen; Han Jianlong; Hu Zhengguo; Chinese Academy of Sciences, Beijing
2007-01-01
The differential cross sections for elastic scattering products of 17 F on 208 Pb have been measured. The angular dispersion plots of ln(dσ/dθ) versus θ 2 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. (authors)
Elastic scattering of He$sup 3$ AT 20 Mev
Energy Technology Data Exchange (ETDEWEB)
Klingensmith, R. W.; Hausman, H. J.; Ploughe, W. D.
1963-08-15
Absolute differential elastic scattering cross sections were measured for the scattering of 20-Mev /sup 3/He particles from V, Ni, Cu, Rh, /sup 118/Sn, Sm, Yb, and Pb. Where practical the measurements were made at laboratory angles extending from 20 to 170 degrees. The diffraction-like oscillations exhibited by the elastic-to-Coulomb cross section ratios are not highly pronounced. A preliminary optical model analysis was carried out using the HUNTER automatic search code of Drisko and Bassel. A Woods-Saxon potential with Thomas type spin-orbit coupling was considered. Reasonable fits to the data were obtained. (auth)
Multigroup P8 - elastic scattering matrices of main reactor elements
International Nuclear Information System (INIS)
Garg, S.B.; Shukla, V.K.
1979-01-01
To study the effect of anisotropic scattering phenomenon on shielding and neutronics of nuclear reactors multigroup P8-elastic scattering matrices have been generated for H, D, He, 6 Li, 7 Li, 10 B, C, N, O, Na, Cr, Fe, Ni, 233 U, 235 U, 238 U, 239 Pu, 240 Pu, 241 Pu and 242 Pu using their angular distribution, Legendre coefficient and elastic scattering cross-section data from the basic ENDF/B library. Two computer codes HSCAT and TRANS have been developed to complete this task for BESM-6 and CDC-3600 computers. These scattering matrices can be directly used as input to the transport theory codes ANISN and DOT. (auth.)
Proton-4He elastic scattering at intermediate energies
International Nuclear Information System (INIS)
Auger, J.P.; Gillespie, J.; Lombard, R.J.
1975-12-01
Differential elastic cross sections and polarizations are calculated in a multiple scattering formalism for proton- 4 He scattering for energies in the range 0.6-24GeV and for momentum transfers up to 4.0fmsup(-1). The calculations include Coulomb and spin effects. Corrections due to target-nucleon overlap and charge exchange are estimated. The results are compared with experimental data [fr
Elastic scattering of low energy electrons by hydrogen molecule
International Nuclear Information System (INIS)
Freitas, L.C.G.; Mu-Tao, L.; Botelho, L.F.
1987-01-01
The coherent version of the Renormalized Multiple-Centre Potential Model (RMPM) has been extended to treat the elastic scattering of low energy electrons by H2 molecule. The intramolecular Multiple Scattering (MS) effect has also been included. The comparison against the experimental data shows that the inclusion of the MS improves significantly with experiment. The extension of the present method to study electron-polyatomic molecule interaction is also discussed. (author) [pt
Scattering resonances in a degenerate Fermi gas
DEFF Research Database (Denmark)
Challis, Katharine; Nygaard, Nicolai; Mølmer, Klaus
2009-01-01
We consider elastic single-particle scattering from a one-dimensional trapped two-component superfluid Fermi gas when the incoming projectile particle is identical to one of the confined species. Our theoretical treatment is based on the Hartree-Fock ground state of the trapped gas...
Extreme values of the analyzing power in dα elastic scattering
International Nuclear Information System (INIS)
Jenny, B.; Grueebler, W.; Koenig, V.; Schmelzbach, P.A.
1985-01-01
An investigation of states of maximum possible polarization in dα elastic scattering has been carried out between 3 and 43 MeV deuteron energy. Two different types of such maxima were found. In the first type, analyzing power components reach their theoretical maximum values. A second type does not generally yield observables with maximum possible values, but has parameters that lie well within the range allowed. It is particular combination of values that constitutes a state of maximum possible polarization. The search for the two types of maxima was made with the aid of a phase-shift analysis. Several maxima of both kinds were found in the elastic scattering under investigation. The energies and scattering angles for these points have been determined. In most cases a state of maximum polarization indicates a resonant state in the compound system. (orig.)
Rayleigh scattering and nonlinear inversion of elastic waves
Energy Technology Data Exchange (ETDEWEB)
Gritto, Roland [Univ. of California, Berkeley, CA (United States)
1995-12-01
Rayleigh scattering of elastic waves by an inclusion is investigated and the limitations determined. In the near field of the inhomogeneity, the scattered waves are up to a factor of 300 stronger than in the far field, excluding the application of the far field Rayleigh approximation for this range. The investigation of the relative error as a function of parameter perturbation shows a range of applicability broader than previously assumed, with errors of 37% and 17% for perturbations of -100% and +100%, respectively. The validity range for the Rayleigh limit is controlled by large inequalities, and therefore, the exact limit is determined as a function of various parameter configurations, resulting in surprisingly high values of up to k_{p}R = 0.9. The nonlinear scattering problem can be solved by inverting for equivalent source terms (moments) of the scatterer, before the elastic parameters are determined. The nonlinear dependence between the moments and the elastic parameters reveals a strong asymmetry around the origin, which will produce different results for weak scattering approximations depending on the sign of the anomaly. Numerical modeling of cross hole situations shows that near field terms are important to yield correct estimates of the inhomogeneities in the vicinity of the receivers, while a few well positioned sources and receivers considerably increase the angular coverage, and thus the model resolution of the inversion parameters. The pattern of scattered energy by an inhomogeneity is complicated and varies depending on the object, the wavelength of the incident wave, and the elastic parameters involved. Therefore, it is necessary to investigate the direction of scattered amplitudes to determine the best survey geometry.
Information on pion-nucleus optical potentials from elastic scattering
International Nuclear Information System (INIS)
Friedman, E.
1983-02-01
Data on the elastic scattering of pions by nuclei between 20 and 230 MeV is analyzed in an almost model-independent fashion. The real part of the potential, which is described by a bias-free Fourier-Bessel series, is found to have the typical Kisslinger or Laplacian-like shape between 30 and 80 MeV
Proton-proton elastic scattering with massive gluons
International Nuclear Information System (INIS)
Sauter, Werner K.; Ducati, M.B. Gay
2001-01-01
In this contribution different approaches to generate a gluon mass are discussed. More specially a recent result for the gluon propagator with a dynamical mass, proposal by Gorbar and Natale, is used in connection with the Landshoff-Nachtmann model for the Pomeron to describe the elastic differential cross section for pp scattering, with good agreement. (author)
Elastic scattering of surface plasmon polaritons: Modeling and experiment
DEFF Research Database (Denmark)
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...
Description of elastic scattering in U-matrix method
International Nuclear Information System (INIS)
Edneral, V.F.; Troshin, S.M.; Tyurin, N.E.; Khrustalev, O.A.
1975-01-01
The elastic pp-scattering has been analyzed using a generalized reaction matrix (the U-matrix). A good agreement has been reached with the experimental total cross sections for the (pp) reaction beginning with an energy of 30 GeV and for the dsub(t)(dt)(pp) for four ISR energies [ru
Double folding model analysis of elastic scattering of halo nucleus ...
Indian Academy of Sciences (India)
carried out which provide valuable insight for improving our understanding of nuclear reactions. One of the interesting aspects is to understand the effect of the halo structure, on elastic scattering cross-sections at near-Coulomb barrier energies in reactions induced by neutron halo nuclei and weakly bound radioactive ...
Neutron-proton elastic scattering at high energies
Energy Technology Data Exchange (ETDEWEB)
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.
Alpha-deuteron elastic scattering around 40 MeV
International Nuclear Information System (INIS)
De, A.; Karmakar, S.; Roychaudhury, T.; Dasgupta, S.S.; Chintalapudi, S.N.; Ismail, M.; Banerjee, S.R.; Divatia, A.S.
1989-01-01
Differential cross section for alpha-deuteron elastic scattering has been measured at several energies around 40 MeV incident alpha. General behaviour of angular distributions remaining close to that predicted by Faddeev type calculations, a sharp energy dependence is observed. (author). 8 refs
TOTEM Results on Elastic Scattering and Total Cross-Section
Kašpar, Jan
2015-01-01
TOTEM is an LHC experiment dedicated to forward hadronic physics. In this contribution, two main parts of its physics programme - proton-proton elastic scattering and total cross-section - are discussed. The analysis procedures are outlined and their status is reviewed.
The Current Status of High Energy Elastic Scattering
Block, Martin M.; Kang, Kyungsik; White, Alan R.
The recent total cross section, σtot, and ρ-value results from the Fermilab Tevatron Collider experiments,1,2 presented at the 4th “Blois” Workshop on Elastic and Diffractive Scattering, held at Elba in May 1991, provide a natural springboard from which to launch a focused review of the field.
Phenomenological models of elastic nucleon scattering and predictions for LHC
Czech Academy of Sciences Publication Activity Database
Kašpar, J.; Kundrát, Vojtěch; Lokajíček, Miloš; Procházka, J.
2010-01-01
Roč. 843, č. 1 (2010), s. 84-106 ISSN 0550-3213 R&D Projects: GA MŠk LA08015 Institutional research plan: CEZ:AV0Z10100502 Keywords : high energy elastic hadron scattering Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 4.642, year: 2010
Large-t elastic scattering and diffraction dissocation
International Nuclear Information System (INIS)
Timmermans, J.
1985-01-01
Recent results, both from the ISR and the S anti p pS Collider, on proton-antiproton elastic scattering at large values of the four-momentum transfer squared, are presented. The results are compared with predictions of several theoretical models of high-energy collisions. Single diffraction dissociation at the Collider is also discussed. (author)
Large-t elastic scattering and diffraction dissocation
International Nuclear Information System (INIS)
Timmermans, J.
1985-05-01
Recent results, both from the ISR and the SantippS Collider, on proton-antiproton elastic scattering at large values of the four-momentum transfer squared, are presented. The results are compared with predictions of several theoretical models of high-energy collisions. Single diffraction dissociation at the Collider is also discussed. (orig.)
Simulating elastic light scattering using high performance computing methods
Hoekstra, A.G.; Sloot, P.M.A.; Verbraeck, A.; Kerckhoffs, E.J.H.
1993-01-01
The Coupled Dipole method, as originally formulated byPurcell and Pennypacker, is a very powerful method tosimulate the Elastic Light Scattering from arbitraryparticles. This method, which is a particle simulationmodel for Computational Electromagnetics, has one majordrawback: if the size of the
Resonant neutrino scattering: An impossible experiment?
International Nuclear Information System (INIS)
Suzuki, D.; Sumikama, T.; Ogura, M.; Mittig, W.; Shiraki, A.; Ichikawa, Y.; Kimura, H.; Otsu, H.; Sakurai, H.; Nakai, Y.; Hussein, M.S.
2010-01-01
The experimental feasibility was investigated for the resonant scattering of monoenergetic neutrinos emitted in the two-body β decay. A simple general formula shows that the resonance cross section can be as large as of the order of 10 -17 cm 2 . The Moessbauer setup using a solid crystal was examined with a focus on the electronic structure of the emitter and the absorber. Based on realistic calculations, we show that interactions of valence electrons in the solid lead to a level broadening of the atomic ground state, which considerably suppresses the resonant scattering of neutrinos.
Alpha resonant scattering for astrophysical reaction studies
Energy Technology Data Exchange (ETDEWEB)
Yamaguchi, H.; Kahl, D.; Nakao, T. [Center for Nuclear Study (CNS), University of Tokyo, RIKEN campus, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Wakabayashi, Y.; Kubano, S. [The Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Hashimoto, T. [Research Center for Nuclear Physics (RCNP), Osaka University, 10-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Hayakawa, S. [Istituto Nazionale Fisica Nucleare - Laboratori Nazionali del Sud (INFN-LNS), Via S. Sofia 62, 95125 Catania (Italy); Kawabata, T. [Department of Physics, Kyoto University, Kita-Shirakawa, Kyoto 606-8502 (Japan); Iwasa, N. [Department of Physics, Tohoku University, Aoba, Sendai, Miyagi 980-8578 (Japan); Teranishi, T. [Department of Physics, Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581 (Japan); Kwon, Y. K. [Institute for Basic Science, 70, Yuseong-daero 1689-gil, Yuseong-gu, Daejeon 305-811 (Korea, Republic of); Binh, D. N. [30 MeV Cyclotron Center, Tran Hung Dao Hospital, Hoan Kiem District, Hanoi (Viet Nam); Khiem, L. H.; Duy, N. G. [Institute of Physics, Vietnam Academy of Science and Technology, 18 Hong Quoc Viet, Nghia do, Hanoi (Viet Nam)
2014-05-02
Several alpha-induced astrophysical reactions have been studied at CRIB (CNS Radioactive Ion Beam separator), which is a low-energy RI beam separator at Center for Nuclear Study (CNS) of the University of Tokyo. One of the methods to study them is the α resonant scattering using the thick-target method in inverse kinematics. Among the recent studies at CRIB, the measurement of {sup 7}Be+α resonant scattering is discussed. Based on the result of the experiment, we evaluated the contributions of high-lying resonances for the {sup 7}Be(α,γ) reaction, and proposed a new cluster band in {sup 11}C.
Alpha resonant scattering for astrophysical reaction studies
International Nuclear Information System (INIS)
Yamaguchi, H.; Kahl, D.; Nakao, T.; Wakabayashi, Y.; Kubano, S.; Hashimoto, T.; Hayakawa, S.; Kawabata, T.; Iwasa, N.; Teranishi, T.; Kwon, Y. K.; Binh, D. N.; Khiem, L. H.; Duy, N. G.
2014-01-01
Several alpha-induced astrophysical reactions have been studied at CRIB (CNS Radioactive Ion Beam separator), which is a low-energy RI beam separator at Center for Nuclear Study (CNS) of the University of Tokyo. One of the methods to study them is the α resonant scattering using the thick-target method in inverse kinematics. Among the recent studies at CRIB, the measurement of 7 Be+α resonant scattering is discussed. Based on the result of the experiment, we evaluated the contributions of high-lying resonances for the 7 Be(α,γ) reaction, and proposed a new cluster band in 11 C
XUV and x-ray elastic scattering of attosecond electromagnetic pulses on atoms
Rosmej, F. B.; Astapenko, V. A.; Lisitsa, V. S.
2017-12-01
Elastic scattering of electromagnetic pulses on atoms in XUV and soft x-ray ranges is considered for ultra-short pulses. The inclusion of the retardation term, non-dipole interaction and an efficient scattering tensor approximation allowed studying the scattering probability in dependence of the pulse duration for different carrier frequencies. Numerical calculations carried out for Mg, Al and Fe atoms demonstrate that the scattering probability is a highly nonlinear function of the pulse duration and has extrema for pulse carrier frequencies in the vicinity of the resonance-like features of the polarization charge spectrum. Closed expressions for the non-dipole correction and the angular dependence of the scattered radiation are obtained.
Singlet channel coupling in deuteron elastic scattering at intermediate energies
International Nuclear Information System (INIS)
Al-Khalili, J.S.; Tostevin, J.A.; Johnson, R.C.
1990-01-01
Intermediate energy deuteron elastic scattering is investigated in a three-body model incorporating relativistic kinematics. The effects of deuteron breakup to singlet spin intermediate states, on the elastic scattering observables for the 58 Ni(d vector, d) 58 Ni reaction at 400 and 700 MeV, are studied quantitatively. The singlet-breakup contributions to the elastic amplitude are estimated within an approximate two-step calculation. The calculation makes an adiabatic approximation in the intermediate states propagator which allows the use of closure over the np intermediate states continuum. The singlet channel coupling is found to produce large effects on the calculated reaction tensor analysing power A yy , characteristic of a dynamically induced second-rank tensor interaction. By inspection of the calculated breakup amplitudes we show this induced interaction to be of the T L tensor type. (orig.)
Do we understand elastic scattering up to LHC energies?
Energy Technology Data Exchange (ETDEWEB)
Soffer, Jacques [Physics Department, Temple University, Philadelphia, PA 19122-6082 (United States)
2013-04-15
The measurements of high energy (bar sign)pp and pp elastic at ISR, SPS, and Tevatron colliders have provided usefull informations on the behavior of the scattering amplitude. A large step in energy domain is accomplished with the LHC collider presently running, giving a unique opportunity to improve our knowledge on the asymptotic regime of the elastic scattering amplitude and to verify the validity of our theoretical approach, to describe the total cross section {sigma}{sub tot}(s), the total elastic cross section {sigma}{sub el}(s), the ratio of the real to imaginary parts of the forward amplitude {rho}(s) and the differential cross section d{sigma} (s,t)/dt.
Antinucleon-nucleus elastic and inelastic scattering
International Nuclear Information System (INIS)
Dover, C.B.; Millener, D.J.
1985-01-01
A general overview of the utility of antinucleon (anti N)-nucleus inelastic scattering studies is presented, emphasizing both the sensitivity of the cross sections to various components of the N anti N transition amplitudes and the prospects for the exploration of some novel aspects of nuclear structure. We start with an examination of the relation between NN and N anti N potentials, focusing on the coherences predicted for the central, spin-orbit and tensor components, and how these may be revealed by measurements of two-body spin observables. We next discuss the role of the nucleus as a spin and isospin filter, and show how, by a judicious choice of final state quantum numbers (natural or unnatural parity states, isospin transfer ΔT = 0 or 1) and momentum transfer q, one can isolate different components of the N anti N transition amplitude. Various models for the N anti N interaction which give reasonable fits to the available two-body data are shown to lead to strikingly different predictions for certain spin-flip nuclear transitions. We suggest several possible directions for future anti N-nucleus inelastic scattering experiments, for instance the study of spin observables which would be accessible with polarized anti N beams, charge exchange reactions, and higher resolution studies of the (anti p, anti p') reaction. We compare the antinucleon and the nucleon as a probe of nuclear modes of excitation. 40 refs., 13 figs
First Principles Calculations for X-ray Resonant Spectra and Elastic Properties
International Nuclear Information System (INIS)
Yongbin Lee
2006-01-01
In this thesis, we discuss applications of first principles methods to x-ray resonant spectra and elastic properties calculation. We start with brief reviews about theoretical background of first principles methods, such as density functional theory, local density approximation (LDA), LDA+U, and the linear augmented plane wave (LAPW) method to solve Kohn-Sham equations. After that we discuss x-ray resonant scattering (XRMS), x-ray magnetic circular dichroism (XMCD) and the branching problem in the heavy rare earths Ledges. In the last chapter we discuss the elastic properties of the second hardest material AlMgB 14
The elastic scattering between heavy ions using Glauber model
International Nuclear Information System (INIS)
Esmael, E.H.; El-Muhbad, SH.A.
2002-01-01
The differential cross sections of the elastic scattering of 1 2 C+ 12 C at energies 1016, 1449 and 2400 MeV and 1 6O +1 2C at energy 1503 MeV are calculated using high energy folding model. An analytical expression for the optical potential is derived. The effect of introducing imaginary phase and the dependence of the ratio of the real to imaginary parts of the forward nucleon-nucleon scattering amplitude on the square of momentum transfer are taken into consideration. Two different types of nuclear densities of the projectile and the target nuclei are considered. The considered systems of interaction are studied by using both modified Glauber I and modified Glauber II. The results show that the elastic scattering differential cross section for the considered interacting systems can be satisfactorily reproduced by this model
Absolute elastic cross sections for electron scattering from SF6
International Nuclear Information System (INIS)
Gulley, R.J.; Uhlmann, L.J.; Dedman, C.J.; Buckman, S.J.; Cho, H.; Trantham, K.W.
2000-01-01
Full text: Absolute differential cross sections for vibrationally elastic scattering of electrons from sulphur hexafluoride (SF 6 ) have been measured at fixed angles of 60 deg, 90 deg and 120 deg over the energy range of 5 to 15 eV, and also at 11 fixed energies between 2.7 and 75 eV for scattering angles between 10 deg and 180 deg. These measurements employ the magnetic angle-changing technique of Read and Channing in combination with the relative flow technique to obtain absolute elastic scattering cross sections at backward angles (135 deg to 180 deg) for incident energies below 15 eV. The results reveal some substantial differences with several previous determinations and a reasonably good level of agreement with a recent close coupling calculation
Comparison of matrix methods for elastic wave scattering problems
International Nuclear Information System (INIS)
Tsao, S.J.; Varadan, V.K.; Varadan, V.V.
1983-01-01
This article briefly describes the T-matrix method and the MOOT (method of optimal truncation) of elastic wave scattering as they apply to A-D, SH- wave problems as well as 3-D elastic wave problems. Two methods are compared for scattering by elliptical cylinders as well as oblate spheroids of various eccentricity as a function of frequency. Convergence, and symmetry of the scattering cross section are also compared for ellipses and spheroidal cavities of different aspect ratios. Both the T-matrix approach and the MOOT were programmed on an AMDHL 470 computer using double precision arithmetic. Although the T-matrix method and MOOT are not always in agreement, it is in no way implied that any of the published results using MOOT are in error
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) .
Detailed Monte Carlo simulation of electron elastic scattering
International Nuclear Information System (INIS)
Chakarova, R.
1994-04-01
A detailed Monte Carlo model is described which simulates the transport of electrons penetrating a medium without energy loss. The trajectory of each electron is constructed as a series of successive interaction events - elastic or inelastic scattering. Differential elastic scattering cross sections, elastic and inelastic mean free paths are used to describe the interaction process. It is presumed that the cross sections data are available and the Monte Carlo algorithm does not include their evaluation. Electrons suffering successive elastic collisions are followed until they escape from the medium or (if the absorption is negligible) their path length exceeds a certain value. The inelastic events are thus treated as absorption. The medium geometry is a layered infinite slab. The electron source could be an incident electron beam or electrons created inside the material. The objective is to obtain the angular distribution, the path length and depth distribution and the collision number distribution of electrons emitted through the surface of the medium. The model is applied successfully to electrons with energy between 0.4 and 20 keV reflected from semi-infinite homogeneous materials with different scattering properties. 16 refs, 9 figs
Elastic scattering and total cross section at very high energies
International Nuclear Information System (INIS)
Castaldi, R.; Sanguinetti, G.
1985-01-01
The aim of this review is to summarize the recent progress in the field of elastic scattering and total cross section in this new energy domain. In Section 2 a survey of the experimental situation is outlined. The most significant data are presented, with emphasis on the interpretation, not the specific details or technicalities. This section is therefore intended to give a self-contained look at the field, especially for the nonspecialist. In Section 3, hadron scattering at high energy is described in an impact parameter picture, which provides a model-independent intuitive geometrical representation. The diffractive character of elastic scattering, seen as the shadow of inelastic absorption, is presented as a consequence of unitarity in the s-channel. Spins are neglected throughout this review, inasmuch as the asymptotic behavior in the very high-energy limit is the main concern here. In Section 4 some relevant theorems are recalled on the limiting behavior of hadron-scattering amplitudes at infinite energy. There is also a brief discussion on how asymptotically rising total cross sections imply scaling properties in the elastic differential cross sections. A quick survey of eikonal models is presented and their predictions are compared with ISR and SPS Collider data
Kinematic aspects of pion-nucleus elastic scattering
International Nuclear Information System (INIS)
Weiss, D.L.; Ernst, D.J.
1982-01-01
The inclusion of relativistic kinematics in the theory of elastic scattering of pions from nuclei is examined. The investigation is performed in the context of the first order impulse approximation which incorporates the following features: (1) Relative momentum are defined according to relativistic theories consistent with time reversal invariance. (2) The two-nucleon interaction is a new, multichannel, separable potential model consistent with the most recent data derived from a recent nonpotential model of Ernst and Johnson. (3) The recoil of the pion-nucleon interacting pair and its resultant nonlocality are included. (4) The Fermi integral is treated by an optimal factorization approximation. It is shown how a careful definition of an intrinsic target density leads to an unambiguous method for including the recoil of the target. The target recoil corrections are found to be large for elastic scattering from 4 He and not negligible for scattering from 12 C. Relativistic potential theory kinematics, kinematics which result from covariant reduction approaches, and kinematics which result from replacing masses by energies in nonrelativistic formulas are compared. The relativistic potential theory kinematics and covariant reduction kinematics are shown to produce different elastic scattering at all pion energies examined (T/sub π/<300 MeV). Simple extensions of nonrelativistic kinematics are found to be reasonable approximations to relativistic potential theory
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 tot(s) and (s), and the measured p differential cross section at =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 GeV2 by the TOTEM group will be crucial to test this structure of the nucleon.
On model-independent analyses of elastic hadron scattering
International Nuclear Information System (INIS)
Avila, R.F.; Campos, S.D.; Menon, M.J.; Montanha, J.
2007-01-01
By means of an almost model-independent parametrization for the elastic hadron-hadron amplitude, as a function of the energy and the momentum transfer, we obtain good descriptions of the physical quantities that characterize elastic proton-proton and antiproton-proton scattering (total cross section, r parameter and differential cross section). The parametrization is inferred on empirical grounds and selected according to high energy theorems and limits from axiomatic quantum field theory. Based on the predictive character of the approach we present predictions for the above physical quantities at the Brookhaven RHIC, Fermilab Tevatron and CERN LHC energies. (author)
Effects of configuration mixing in heavy-ion elastic scattering
International Nuclear Information System (INIS)
Cappuzzello, F.; Bondi, M.; Nicoloso, D.; Tropea, S.; Lubian, J.; Gomes, P.R.S.; Linares, R.; Oliveira, J.R.B.; Chamon, L.C.; Gasques, L.R.; Agodi, C.; Carbone, D.; Cavallaro, M.; Cunsolo, A.; De Napoli, M.; Nunes Garcia, V.; Paes, B.; Foti, A.
2014-01-01
A theoretical study of the influence of configuration mixing on elastic scattering cross section is performed for the system 16 O + 27 Al at 100 MeV. A simple two-state model space, including the 27 Al 5/2 + ground and 5/2 + excited state at 2.73 MeV, is used in the coupled channel equations. The results indicate that even a weak degree of mixing is able to sizeably affect the elastic cross section, determining mainly a damping of Fraunhofer oscillations, as observed in the experiments. (authors)
$pp$ 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.
Tensor polarization in pion-deuteron elastic scattering
International Nuclear Information System (INIS)
Holt, R.J.
1983-01-01
The angular dependence of the tensor polarization t 20 /sup lab/ of recoiling deuterons in π-d elastic scattering was measured as a function of incident pion energy in the range 134 to 256 MeV. No evidence was found for rapid energy or angular dependences in t 20 /sup lab/. The results agree most favorably with theoretical calculations in which the P 11 π-N amplitude has been removed altogether. This agreement is consistent with a small effect of pion absorption on the elastic channel. 14 references
Elastic meson-nucleon partial wave scattering analyses
International Nuclear Information System (INIS)
Arndt, R.A.
1986-01-01
Comprehensive analyses of π-n elastic scattering data below 1100 MeV(Tlab), and K+p scattering below 3 GeV/c(Plab) are discussed. Also discussed is a package of computer programs and data bases (scattering data, and solution files) through which users can ''explore'' these interactions in great detail; this package is known by the acronym SAID (for Scattering Analysis Interactive Dialin) and is accessible on VAX backup tapes, or by dialin to the VPI computers. The π-n, and k+p interactions will be described as seen through the SAID programs. A procedure will be described for generating an interpolating array from any of the solutions encoded in SAID; this array can then be used through a fortran callable subroutine (supplied as part of SAID) to give excellent amplitude reconstructions over a broad kinematic range
Relativistic effects in elastic scattering of electrons in TEM
International Nuclear Information System (INIS)
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.
Multiple scattering effects in depth resolution of elastic recoil detection
International Nuclear Information System (INIS)
Wielunski, L.S.; Harding, G.L.
1998-01-01
Elastic Recoil Detection (ERD) is used to profile hydrogen and other low mass elements in thin films at surface and interfaces in a similar way that Rutherford Backscattering Spectroscopy (RBS) is used to detect and profile heavy elements. It is often assumed that the depth resolutions of these two techniques are similar. However, in contrast to typical RBS, the depth resolution of ERD is limited substantially by multiple scattering. In experimental data analysis and/or spectra simulations of a typical RBS measurement multiple scattering effects are often ignored. Computer programs used in IBA, such as RUMP, HYPRA or RBX do not include multiple scattering effects at all. In this paper, using practical thin metal structures with films containing intentionally introduced hydrogen, we demonstrate experimental ERD depth resolution and sensitivity limitations. The effects of sample material and scattering angle are also discussed. (authors)
Multiple scattering effects in depth resolution of elastic recoil detection
Energy Technology Data Exchange (ETDEWEB)
Wielunski, L.S.; Harding, G.L. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), Lindfield, NSW (Australia). Telecommunications and Industrial Physics; Szilagyi, E. [KFKI Research Institute for Particle and Nuclear Physics, Budapest, (Hungary)
1998-06-01
Elastic Recoil Detection (ERD) is used to profile hydrogen and other low mass elements in thin films at surface and interfaces in a similar way that Rutherford Backscattering Spectroscopy (RBS) is used to detect and profile heavy elements. It is often assumed that the depth resolutions of these two techniques are similar. However, in contrast to typical RBS, the depth resolution of ERD is limited substantially by multiple scattering. In experimental data analysis and/or spectra simulations of a typical RBS measurement multiple scattering effects are often ignored. Computer programs used in IBA, such as RUMP, HYPRA or RBX do not include multiple scattering effects at all. In this paper, using practical thin metal structures with films containing intentionally introduced hydrogen, we demonstrate experimental ERD depth resolution and sensitivity limitations. The effects of sample material and scattering angle are also discussed. (authors). 19 refs., 4 figs.
Photon nuclear scattering on lead and bismuth in the region of the giant resonance
International Nuclear Information System (INIS)
Tamas, Gabriel.
1976-01-01
The results of monochromatic photon nuclear scattering studies on natural lead and bismuth targets are presented. The cross sections for the inelastic scattering leading to the first excited levels of 204 Pb, 206 Pb and 207 Pb are important, in agreement with theoretical predictions. The elastic scattering amplitude is related to the total photon absorption by dispersion relations. It is then possible to determine the spin of resonances excited by the reaction studied. Precise measurements carried out between 14 and 20MeV revealed that the angular distribution cannot be explained by a single dipolar resonance. A quadrupolar resonance at E 2 =14MeV must be introduced [fr
Energy Technology Data Exchange (ETDEWEB)
Stefan, Gheorghe Iulian [Ecole doctorale SIMEM, U.F.R. Sciences, Universite de Caen Basse-Normandie, 14032 Caen Cedex (France)
2006-12-15
This work presents a very accurate experimental method based on radioactive beams for the study of the spectroscopical properties of unbound states. It makes use of inverse kinematical elastic scattering of the ions of an radioactive beam from a target of stable nuclei. An application of the method for the study of radioactive nuclei of astrophysical interests is given, namely of {sup 19}Ne and {sup 16}F nuclei. It is shown that on the basis of the properties of proton-emitting unbound levels of {sup 19}Ne one can develop a method of experimental study of nova explosions. It is based on observation of gamma emissions following the gamma decays of the radionuclides generated in the explosion. The most interesting radioactive nucleus involved in this process is {sup 18}F the yield of which depends strongly on the rate of {sup 18}F(p,{alpha}){sup 15}O reaction. This yield depends in turn of the properties of the states of the ({sup 18}F + p) compound nucleus, i.e. the {sup 19}Ne nucleus. In addition it was studied the unbound {sup 16}F nucleus also of astrophysical significance in {sup 15}O rich environment. Since {sup 16}F is an unbound nucleus the reaction of {sup 15}O with protons, although abundant in most astrophysical media, appears to be negligible. Thus the question that was posed was whether the exotic {sup 15}O(p,{beta}{sup +}){sup 16}O resonant reaction acquires some importance in various astrophysical media. In this work one describes a novel approach to study the reaction mechanisms which could change drastically the role of non-bound nuclei in stellar processes. One implies this mechanism to the processes (p,{gamma})({beta}){sup +} and (p,{gamma}) (p,{gamma}) within {sup 15}O rich media. The experimental studies of the {sup 19}Ne and {sup 16}F were carried out with a radioactive beam of {sup 15}O ions of very low energy produced by SPIRAL at GANIL. To improve the energy resolution thin targets were used with a 0 angle of observation relative to the beam
Inversion of electron-water elastic scattering data
International Nuclear Information System (INIS)
Lun, A.; Chen, X.J.; Allen, L.J.; Amos, K.
1994-01-01
Fixed energy inverse scattering theory has been used to analyse the differential cross-sections for the elastic scattering of electrons from water molecules. Both semiclassical (WKB) and fully quantal inversion methods have been used with data taken in the energy range 100 to 1000 eV. Constrained to be real, the local inversion potentials are found to be energy dependent; a dependence that can be interpreted as the local equivalence of true nonlocality in the actual interaction. 14 refs., 4 tabs., 8 figs
Isobaric intermediate states in proton-nucleus elastic scattering
International Nuclear Information System (INIS)
Auger, J.P.; Lazard, C.; Lombard, R.J.
1981-05-01
The effects of the propagation of isobaric nucleon states in the intermediate steps of the multiple scattering have been studied with application on the proton- 4 He elastic scattering at 1 GeV. The calculations are performed in the Glauber model and results are given for the differential cross section, the polarization and the spin rotation parameter. In our conclusions we stress the large cancellations observed between terms of various orders and the great sensitivity of the effects to the nucleon-nucleon amplitudes
Model of K+p elastic scattering at high energies
International Nuclear Information System (INIS)
Fazal-e-Aleem
1985-01-01
Very recent measurements of the angular distribution for K + p elastic scattering which show a structure near -t = 3.8(GeV/c) 2 , together with the total cross section and ratio of the real and imaginary parts of the scattering amplitude for 50 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) 2 observed in the differential cross section has also been explained
Normal Spin Asymmetries in Elastic Electron-Proton Scattering
International Nuclear Information System (INIS)
M. Gorchtein; P.A.M. Guichon; M. Vanderhaeghen
2004-01-01
We discuss the two-photon exchange contribution to observables which involve lepton helicity flip in elastic lepton-nucleon scattering. This contribution is accessed through the single spin asymmetry for a lepton beam polarized normal to the scattering plane. We estimate this beam normal spin asymmetry at large momentum transfer using a parton model and we express the corresponding amplitude in terms of generalized parton distributions. We further discuss this observable in the quasi-RCS kinematics which may be dominant at certain kinematical conditions and find it to be governed by the photon helicity-flip RCS amplitudes
Normal Spin Asymmetries in Elastic Electron-Proton Scattering
International Nuclear Information System (INIS)
Gorchtein, M.; Guichon, P.A.M.; Vanderhaeghen, M.
2005-01-01
We discuss the two-photon exchange contribution to observables which involve lepton helicity flip in elastic lepton-nucleon scattering. This contribution is accessed through the single spin asymmetry for a lepton beam polarized normal to the scattering plane. We estimate this beam normal spin asymmetry at large momentum transfer using a parton model and we express the corresponding amplitude in terms of generalized parton distributions. We further discuss this observable in the quasi-RCS kinematics which may be dominant at certain kinematical conditions and find it to be governed by the photon helicity-flip RCS amplitudes
Multiple scattering problems in heavy ion elastic recoil detection analysis
International Nuclear Information System (INIS)
Johnston, P.N.; El Bouanani, M.; Stannard, W.B.; Bubb, I.F.; Cohen, D.D.; Dytlewski, N.; Siegele, R.
1998-01-01
A number of groups use Heavy Ion Elastic Recoil Detection Analysis (HIERDA) to study materials science problems. Nevertheless, there is no standard methodology for the analysis of HIERDA spectra. To overcome this deficiency we have been establishing codes for 2-dimensional data analysis. A major problem involves the effects of multiple and plural scattering which are very significant, even for quite thin (∼100 nm) layers of the very heavy elements. To examine the effects of multiple scattering we have made comparisons between the small-angle model of Sigmund et al. and TRIM calculations. (authors)
Small angle elastic scattering of electrons by noble gas atoms
International Nuclear Information System (INIS)
Wagenaar, R.W.
1984-01-01
In this thesis, measurements are carried out to obtain small angle elastic differential cross sections in order to check the validity of Kramers-Kronig dispersion relations for electrons scattered by noble gas atoms. First, total cross sections are obtained for argon, krypton and xenon. Next, a parallel plate electrostatic energy analyser for the simultaneous measurement of doubly differential cross section for small angle electron scattering is described. Also absolute differential cross sections are reported. Finally the forward dispersion relation for electron-helium collisions is dealt with. (Auth.)
Hybrid Theory of Electron-Hydrogenic Systems Elastic Scattering
Bhatia, A. K.
2007-01-01
Accurate electron-hydrogen and electron-hydrogenic cross sections are required to interpret fusion experiments, laboratory plasma physics and properties of the solar and astrophysical plasmas. We have developed a method in which the short-range and long-range correlations can be included at the same time in the scattering equations. The phase shifts have rigorous lower bounds and the scattering lengths have rigorous upper bounds. The phase shifts in the resonance region can be used to calculate very accurately the resonance parameters.
Measurement of neutrino flux from neutrino-electron elastic scattering
Park, J.; Aliaga, L.; Altinok, O.; Bellantoni, L.; Bercellie, A.; Betancourt, M.; Bodek, A.; Bravar, A.; Budd, H.; Cai, T.; Carneiro, M. F.; Christy, M. E.; Chvojka, J.; da Motta, H.; Dytman, S. A.; Díaz, G. A.; Eberly, B.; Felix, J.; Fields, L.; Fine, R.; Gago, A. M.; Galindo, R.; Ghosh, A.; Golan, T.; Gran, R.; Harris, D. A.; Higuera, A.; Kleykamp, J.; Kordosky, M.; Le, T.; Maher, E.; Manly, S.; Mann, W. A.; Marshall, C. M.; Martinez Caicedo, D. A.; McFarland, K. S.; McGivern, C. L.; McGowan, A. M.; Messerly, B.; Miller, J.; Mislivec, A.; Morfín, J. G.; Mousseau, J.; Naples, D.; Nelson, J. K.; Norrick, A.; Nuruzzaman; Osta, J.; Paolone, V.; Patrick, C. E.; Perdue, G. N.; Rakotondravohitra, L.; Ramirez, M. A.; Ray, H.; Ren, L.; Rimal, D.; Rodrigues, P. A.; Ruterbories, D.; Schellman, H.; Solano Salinas, C. J.; Tagg, N.; Tice, B. G.; Valencia, E.; Walton, T.; Wolcott, J.; Wospakrik, M.; Zavala, G.; Zhang, D.; Miner ν A Collaboration
2016-06-01
Muon-neutrino elastic scattering on electrons is an observable neutrino process whose cross section is precisely known. Consequently a measurement of this process in an accelerator-based νμ beam can improve the knowledge of the absolute neutrino flux impinging upon the detector; typically this knowledge is limited to ˜10 % due to uncertainties in hadron production and focusing. We have isolated a sample of 135 ±17 neutrino-electron elastic scattering candidates in the segmented scintillator detector of MINERvA, after subtracting backgrounds and correcting for efficiency. We show how this sample can be used to reduce the total uncertainty on the NuMI νμ flux from 9% to 6%. Our measurement provides a flux constraint that is useful to other experiments using the NuMI beam, and this technique is applicable to future neutrino beams operating at multi-GeV energies.
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.
Elastic nucleon-deuteron scattering and breakup with chiral forces
Directory of Open Access Journals (Sweden)
Witała Henryk
2016-01-01
Full Text Available Results on three-nucleon (3N elastic scattering and breakup below the pion production threshold are discussed. The large discrepancies found between a theory based on numerical solutions of 3N Faddeev equations with standard nucleon-nucleon (NN potentials only and data point to the need for three-nucleon forces (3NF’s. This notion is supported by the fact that another possible reason for the discrepancies in elastic nucleon-deuteron (Nd scattering, relativistic effects, turned out to be small. Results for a new generation of chiral NN forces (up to N4LO together with theoretical truncation errors are shown. They support conclusions obtained with standard NN potentials
The elastic scattering of 14N by 10B
International Nuclear Information System (INIS)
Takai, H.
1986-01-01
The elastic scattering 10 B( 14 N, 14 N) 10 B was studied for four incident energies: 38.1, 42.0, 46.0 and 50.0 MeV. The angular distributions for these energies were determined in the center of mass frame from 16 0 to 176 0 with the introduction of target nucleus recoil detection techniques in a magnetic spectrograph with gas position sensitive detectors and in a scattering chamber with an Σ-ΔΣ detection system. For the forward angles, the angular distributions are well described by the optical model. For the backward angles, up to 160 0 , a satisfactory description is obtained by the elastic transfer analysis; for larger angles an accentuated deviation id observed. (author) [pt
Invariant potential for elastic pion--nucleus scattering
International Nuclear Information System (INIS)
Cammarata, J.B.; Banerjee, M.K.
1976-01-01
From the Wick-Dyson expansion of the exact propagator of a pion in the presence of a nucleus, an invariant potential for crossing symmetric elastic pion-nucleus scattering is obtained in terms of a series of pion-nucleon diagrams. The Chew-Low theory is used to develop a model in which the most important class of diagrams is effectively summed. Included in this model is the exclusion principle restriction on the pion-bound nucleon interaction, the effects of the binding of nucleons, a kinematic transformation of energy from the lab to the πN center of mass frame, and the Fermi motion and recoil of the target nucleons. From a numerical study of the effects of these processes on the π- 12 C total cross section, the relative importance of each is determined. Other processes contributing to the elastic scattering of pions not included in the present model are also discussed
Differential cross sections for e-bar CO elastic scattering
International Nuclear Information System (INIS)
Raj, Deo; Meetu
2005-01-01
In a recent investigation, Raj and Kumar modified the absorption potential of Staszewska el at al in such a way that it yielded the best agreement between theory and experiment for elastic cross sections when applied to e-bar - O 2 scattering over a wide incident energy range. In the present investigation, the same modified absorption potential of Raj and Kumar has been employed to obtain the elastic differential cross sections (EDCS) for electron scattering by CO molecules at intermediate energies (100-800 eV). The independent atom model alongwith partial waves has been used for these calculations.The present results of EDCS are in fairly good agreement with the experimental data. (author)
Proton-proton elastic scattering measurements at COSY
Energy Technology Data Exchange (ETDEWEB)
Bagdasarian, Zara [Forschungszentrum Juelich, Juelich (Germany); Tbilisi State University, Tbilisi (Georgia); Collaboration: ANKE-Collaboration
2014-07-01
To construct the reliable phase shift analysis (PSA) that can successfully describe the nucleon-nucleon (NN) interaction it is necessary to measure variety of experimental observables for both proton-proton (pp) and neutron-proton (np) elastic scattering. The polarized beams and targets at COSY-ANKE facility allow a substantial contribution to the existing database. The experiment was carried out in April 2013 at ANKE using a transversely polarized proton beam incident on an unpolarized hydrogen cluster target. Six beam energies of T{sub p}=0.8,1.6,1.8,2.0,2.2,2.4 GeV were used. The aim of this talk is to present the preliminary results for the analyzing power (A{sub y}) for the pp elastic scattering in the so-far unexplored 5 <θ{sub cm}<30 angular range. Our measurements are also compared to the world data and current partial wave solutions.
Nucleon in nuclei from quasi-elastic electron scattering
International Nuclear Information System (INIS)
Gerard, A.
1987-04-01
One challenging problem in modern nuclear physics is to understand how the internal structure of the nucleon interferes with the dynamics of nucleons in a nucleus. The purpose of this paper is to review the present status of data in quasi-elastic electron scattering, to connect them with recent theoretical developments and to outline some future directions of research not accessible to present electron facilities
Systematics of elastic scattering at high and intermediate energy
Energy Technology Data Exchange (ETDEWEB)
Dias De Deus, J [Instituto de Fisica e Matematica, Lisboa (Portugal); Kroll, P [Wuppertal Univ. (Gesamthochschule) (Germany, F.R.)
1977-01-01
A model for elastic scattering valid in the intermediate and high-energy region is proposed. The model includes three kinds of entities: the pomeron, a universal GS pomeron; the reggeons, also universal and of GS type; and the core, a low-energy central real piece required by dispersion relations. The number of free functions and parameters is rather small. The approach supports naive duality and, in general, agrees with the results of absorptive models.
Polarized deuteron elastic scattering from a polarized proton target
Energy Technology Data Exchange (ETDEWEB)
Schmelzer, R.; Kuiper, H.; Schoeberl, M.; Berber, S.; Hilmert, H.; Koeppel, R.; Pferdmenges, R. (Erlangen-Nuernberg Univ., Erlangen (Germany, F.R.). Physikalisches Inst.); Zankel, H. (Graz Univ. (Austria). Inst. fuer Theoretische Physik)
1983-01-13
Measurements are reported of the spin correlation parameter Cy,y for the elastic scattering of 10.0 MeV vector polarized deuterons from a polarized proton target at five CM angles (76/sup 0/,85/sup 0/,98/sup 0/,115/sup 0/,132/sup 0/). The experimental results are compared with different predictions. A Faddeev type calculation on the basis of local potentials also including approximate Coulomb distortion is favoured by our experimental results.
Polarized deuteron elastic scattering from a polarized proton target
International Nuclear Information System (INIS)
Schmelzer, R.; Kuiper, H.; Schoeberl, M.; Berber, S.; Hilmert, H.; Koeppel, R.; Pferdmenges, R.; Zankel, H.
1983-01-01
Measurements are reported of the spin correlation parameter Cy,y for the elastic scattering of 10.0 MeV vector polarized deuterons from a polarized proton target at five CM angles (76 0 ,85 0 ,98 0 ,115 0 ,132 0 ). The experimental results are compared with different predictions. A Faddeev type calculation on the basis of local potentials also including approximate Coulomb distortion is favoured by our experimental results. (orig.)
Total cross sections and elastic scattering at the SSC
Energy Technology Data Exchange (ETDEWEB)
Foley, K.J.
1985-12-05
The need is discussed of a special purpose detector for the measurement of elastic scattering at the SSC. The detector would cover as small a solid angle as is practical. Two techniques are described briefly to measure total cross sections at hadron storage rings. The direct method is to measure the interaction rate in an IR of known luminosity - a method that gets more difficult increasing energy. A second method is to use the optical theorem. 6 refs., 1 fig. (LEW)
Polarization Measurements in elastic electron-deuteron scattering
International Nuclear Information System (INIS)
Garcon, M.
1989-01-01
The deuteron electromagnetic form factors, are recalled. The experiment, recently performed in the Bates accelerator (M.I.T.), is described. The aim of the experiment is the measurement of the tensor polarization of the backscattered deuteron, in the elastic electron-deuteron scattering, up to q = 4.6 f/m. Different experimental methods, concerning the determination of this observable, are compared. Several improvement possibilities in this field are suggested
Proton-proton elastic scattering at ultrahigh energies
International Nuclear Information System (INIS)
Saleem, M.; Shaukat, M.A.; Fazal-e-Aleem
1981-01-01
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. (author)
Proton-proton elastic scattering at ultrahigh energies
Energy Technology Data Exchange (ETDEWEB)
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.
The complete experiment for backward elastic dp scattering
International Nuclear Information System (INIS)
Rekalo, M.P.; Piskunov, N.M.; Sitnik, I.M.
1996-01-01
The problem of the complete experiment in backward elastic dp scattering is analyzed. All effects due to polarization of one or two initial and one of secondary particles are considered. It is shown that the minimal set of measurements allowing to reconstruct each of four amplitudes describing this process does not comprise too complicated experiments and is quite realistic nowadays. The geography of realization of the complete experiment is briefly reviewed. 21 refs
Elastic scattering crossovers from 50 to 175 GeV
International Nuclear Information System (INIS)
Anderson, R.L.; Ayres, D.S.; Barton, D.S.; Brenner, A.E.; Butler, J.; Cutts, D.; DeMarzo, C.; Diebold, R.; Elias, J.E.; Fines, J.; Friedman, J.I.; Gittelman, B.; Gottschalk, B.; Guerriero, L.; Gustavson, D.; Kendall, H.W.; Lanou, R.E.; Lavopa, P.; Levinson, L.J.; Litt, J.; Loh, E.; Maclay, G.J.; Maggi, G.; Massimo, J.T.; Meunier, R.; Mikenberg, G.; Nelson, B.; Posa, F.; Rich, K.; Ritson, D.M.; Rosenson, L.; Selvaggi, G.; Sogard, M.; Spinelli, P.; Verdier, R.; Waldner, F.; Weitsch, G.A.
1976-01-01
A comparison of K/sup plus-or-minus/p and p/sup plus-or-minus/p elastic scattering is made for incident energy 50 to 175 GeV. Average values of 0.19 +- 0.04 and 0.11 +- 0.02 GeV 2 were found for the invariant-momentum-transfer values of the Kp and pp crossover points, respectively
Elastic and quasielastic scattering of light nuclei in the theory of multiple scattering
International Nuclear Information System (INIS)
Ismatov, E.I.; Kuterbekov, K.A.; Dzhuraev, Sh.Kh.; Ehsaniyazov, Sh.P.; Zholdasova, S.M.
2005-01-01
In the work the calculation method for diffraction scattering amplitudes of light nuclei by heavy nuclei is developed. For A 1 A 2 -scattering effects of pair-, three-fold, and four-fold screenings are estimated. It is shown, that in amplitude calculations for A 1 A 2 elastic scattering it is enough come to nothing more than accounting of total screenings in the first order. Analysis of nucleus-nucleus scattering sensitive characteristics to choice of single-particle nuclear densities parametrization is carried out
Microscopic cluster model analysis of 14O+p elastic scattering
International Nuclear Information System (INIS)
Baye, D.; Descouvemont, P.; Leo, F.
2005-01-01
The 14 O+p elastic scattering is discussed in detail in a fully microscopic cluster model. The 14 O cluster is described by a closed p shell for protons and a closed p3/2 subshell for neutrons in the translation-invariant harmonic-oscillator model. The exchange and spin-orbit parameters of the effective forces are tuned on the energy levels of the 15 C mirror system. With the generator-coordinate and microscopic R-matrix methods, phase shifts and cross sections are calculated for the 14 O+p elastic scattering. An excellent agreement is found with recent experimental data. A comparison is performed with phenomenological R-matrix fits. Resonances properties in 15 F are discussed
Vertical motion and elastic light-scattering of a laser-levitated water droplet
International Nuclear Information System (INIS)
Chan, C. W.; Lee, W. K.
2001-01-01
We report the vertical motion and elastic scattered light of a single laser-levitated water microdroplet as it slowly evaporated. The vertical displacement as a function of time exhibited peaks of a variety of widths. Morphology-dependent resonances (MDRs) that induced the displacement peaks were identified. We found that the Stokes equation is adequate to describe the vertical motions driven by broad MDRs. For motions driven by relatively narrow MDRs, significant deviations from results predicted by the Stokes equation were found. The elastic scattered light intensity as a function of the size of the droplet showed sudden increases attributable to deformations of the droplet as its size parameter scanned through narrow MDRs. Copyright 2001 Optical Society of America
Molecular bonding in SF6 measured by elastic electron scattering
International Nuclear Information System (INIS)
Miller, J.D.; Fink, M.
1992-01-01
Elastic differential cross-section measurements of gaseous SF 6 were made with 30 keV electrons in the range of 0.25 bohrs -1 ≤s≤10 bohrs -1 . Structural parameters derived in this study closely matched those found in an earlier total (elastic plus inelastic) scattering investigation. Multiple-scattering effects were incorporated in the structural refinement. The discrepancies between the independent atom model and the measured differential cross section reproduce earlier total scattering results for momentum transfers of greater than 5 bohrs -1 . By extending the measurements to smaller s values, a closer examination of a Hartree--Fock calculation for SF 6 was possible. It was found that the difference curve obtained from the Hartree--Fock calculation matched the experimental data in this region. A more quantitative analysis was performed using the analytic expressions of Bonham and Fink to compute moments of the molecular charge distribution from the differential cross-section data. Comparison of these results with similar fits to the Hartree--Fock calculation confirmed the good agreement between the Hartree--Fock calculation and the current elastic data
The Profile of Inelastic Collisions from Elastic Scattering Data
Directory of Open Access Journals (Sweden)
I. M. Dremin
2015-01-01
Full Text Available Using the unitarity relation in combination with experimental data about the elastic scattering in the diffraction cone, it is shown how the shape and the darkness of the inelastic interaction region of colliding protons change with increase of their energies. In particular, the collisions become fully absorptive at small impact parameters at LHC energies that results in some special features of inelastic processes. Possible evolution of this shape with the dark core at the LHC to the fully transparent one at higher energies is discussed that implies that the terminology of the black disk would be replaced by the black toroid. The approach to asymptotics is disputed. The ratio of the real to imaginary parts of the nonforward elastic scattering amplitude is briefly discussed. All the conclusions are only obtained in the framework of the indubitable unitarity condition using experimental data about the elastic scattering of protons in the diffraction cone without any reference to quantum chromodynamics (QCD or phenomenological approaches.
An orthogonality condition model treatment of elastic and inelastic (α, 12C) scattering
International Nuclear Information System (INIS)
Suzuki, Y.; Imanishi, B.
1981-02-01
Elastic and inelastic scattering of α-particles on the deformed nucleus 12 C are investigated in the range of incident α-particle energies of 9 to 11 MeV by using the coupled-channel method with orthogonality condition. A doubly folded potential generated by the shell model wave functions of the α-particle and the deformed nucleus 12 C is employed for the relative motion between the α-particle and 12 C. Good agreement between theory and experiment is obtained for the elastic and inelastic angular distributions and the resonance structures. It is found, from the Born series expansion of the T-matrix, that the orthogonality constraint stresses the effects of the channel-coupling between the elastic and inelastic processes, and it indicates that the DWBA does not work well in this system. (author)
Resonant Column Tests and Nonlinear Elasticity in Simulated Rocks
Sebastian, Resmi; Sitharam, T. G.
2018-01-01
Rocks are generally regarded as linearly elastic even though the manifestations of nonlinearity are prominent. The variations of elastic constants with varying strain levels and stress conditions, disagreement between static and dynamic moduli, etc., are some of the examples of nonlinear elasticity in rocks. The grain-to-grain contact, presence of pores and joints along with other compliant features induce the nonlinear behavior in rocks. The nonlinear elastic behavior of rocks is demonstrated through resonant column tests and numerical simulations in this paper. Resonant column tests on intact and jointed gypsum samples across varying strain levels have been performed in laboratory and using numerical simulations. The paper shows the application of resonant column apparatus to obtain the wave velocities of stiff samples at various strain levels under long wavelength condition, after performing checks and incorporating corrections to the obtained resonant frequencies. The numerical simulation and validation of the resonant column tests using distinct element method are presented. The stiffness reductions of testing samples under torsional and flexural vibrations with increasing strain levels have been analyzed. The nonlinear elastic behavior of rocks is reflected in the results, which is enhanced by the presence of joints. The significance of joint orientation and influence of joint spacing during wave propagation have also been assessed and presented using the numerical simulations. It has been found that rock joints also exhibit nonlinear behavior within the elastic limit.
Resonant and nonresonant magnetic scattering (invited)
International Nuclear Information System (INIS)
McWhan, D.B.; Hastings, J.B.; Kao, C.; Siddons, D.P.
1992-01-01
The tunability and the polarization of synchrotron radiation open up new possibilities for the study of magnetism. Studies on magnetic materials performed at the National Synchrotron Light Source are reviewed, and they fall into four areas: structure, evolution of magnetic order, separation of L and S, and resonance effects. In the vicinity of atomic absorption edges, the Faraday effect, magnetic circular dichroism, and resonant magnetic scattering are all related resonance effects which measure the spin-polarized density of states. The production and analysis of polarized beams are discussed in the context of the study of magnetism with synchrotron radiation
Pygmy resonances probed with electron scattering
International Nuclear Information System (INIS)
Bertulani, C.A.
2007-01-01
Pygmy resonances in light nuclei excited in electron scattering are discussed. These collective modes will be explored in future electron-ion colliders such as ELISe/FAIR (spokesperson: Haik Simon - GSI). Response functions for direct breakup are explored with few-body and hydrodynamical models, including the dependence upon final state interactions
High-energy elastic and quasi-elastic deuteron-nucleus scattering
International Nuclear Information System (INIS)
Tekou, Amouzou
1974-01-01
A study is made of deuteron-nucleus elastic and quasi-elastic scattering and the connection between the opaque nucleus model and the Glauber model is pointed out. The contributions to different cross-sections of the collisions in which the nucleus, excited by one of the nucleons of the deuteron, is brought back to the ground state by the other nucleon is analysed. Coherent deuteron disintegration is found to be highly improbable when the target nucleus is heavy and incoherent disintegration accounts for nearly all the deuteron disintegration. Thus a correct comparison between theoretical and experimental data on proton stripping must take the incoherent deuteron disintegration into consideration
Anomalous and resonance small-angle scattering
International Nuclear Information System (INIS)
Epperson, J.E.; Thiyagarajan, P.
1988-01-01
Significant changes in the small-angle scattered intensity can be induced by making measurements with radiation close to an absorption edge of an appropriate atomic species contained in the sample. These changes can be related quantitatively to the real and imaginary anomalous-dispersion terms for the scattering factor (X-rays) or scattering length (neutrons). The physics inherent in these anomalous-dispersion terms is first discussed before consideration of how they enter the relevant scattering theory. Two major areas of anomalous-scattering research have emerged; macromolecules in solution and unmixing of metallic alloys. Research in each area is reviewed, illustrating both the feasibility and potential of these techniques. All the experimental results reported to date have been obtained with X-rays. However, it is pointed out that the formalism is the same for the analog experiment with neutrons, and a number of suitable isotopes exist which exhibit resonance in an accessible range of energy. Potential applications of resonance small-angle neutron scattering are discussed. (orig.)
Elastic scattering of protons at the nucleus 6He in the Glauber multiple scattering theory
International Nuclear Information System (INIS)
Prmantayeva, B.A.; Temerbayev, A.A.; Tleulessova, I.K.; Ibrayeva, E.T.
2011-01-01
Calculation is submitted for the differential cross sections of elastic p 6 He-scattering at energies of 70 and 700 MeV/nucleon within the framework of the Glauber theory of multiple diffraction scattering. We used the three-particle wave functions: α-n-n with realistic intercluster potentials. The sensitivity of elastic scattering to the proton-nuclear interaction and the structure of nuclei had been investigated. It is shown that the contribution of small components of the wave function as well as the multiplicity of the scattering operator Ω should be considered to describe a cross-section in broad angular range . A comparison with available experimental data was made. (author)
A new model for elastic deuteron-deuteron scattering
International Nuclear Information System (INIS)
Etim, E.; Satta, L.
1988-01-01
Straightforward application of the Glauber multiple scattering theory is drammatically challenged by data on elastic deuteron-deuteron scattering. The challenge has been argued to be met by an improved representation of the ground state wave function of the deuteron as an admixture of S-and D-waves. In the light of the failure of the Glauber and geometrical picture models in general, to explain proton-proton and proton-antiproton scattering data up to and including collider energies and for all momentum transfers, this argument becomes less and less compelling and more and more unconvincing. A model inspired by unitarity and which produces substantial elastic scattering through a unitarity sum over a specific class of intermediate states is presented. The model fits not only deuteron-deuteron, but also proton-proton, proton-antiproton and αN -> αN (N =α, d, He 3 ) data for all energies and momentum transfers. No detailed knowledge of ground state wave functions is required
Resonances in the proton-6Li scattering
International Nuclear Information System (INIS)
Haller, M.
1986-01-01
The differential cross section and the analyzing power of the p+ 6 Li scattering were measured in the laboratory energy range from 1.6 respectively 2.8 MeV to 10 MeV at 45 respectively 40 energies in full angular distributions. The data were subjected both to an analysis in the optical model which yielded already hints to resonance effects and to a comphrehensive scattering-phase analysis for L=0, 1, and 2 under inclusion of channel spin and orbital angular momentum mixings. The consistent description of all data required the assumption of broad resonance structures. An approximate parametrization by a Breit-Wigner formula allowed the estimation of the resonance parameters. (orig./HSI) [de
Nuclear elasticity applied to giant resonances of fast rotating nuclei
International Nuclear Information System (INIS)
Jang, S.; Bouyssy, A.
1987-06-01
Isoscalar giant resonances in fast rotating nuclei are investigated within the framework of nuclear elasticity by solving the equation of motion of elastic nuclear medium in a rotating frame of reference. Both Coriolis and centrifugal forces are taken into account. The nuclear rotation removes completely the azimuthal degeneracy of the giant resonance energies. Realistic large values of the angular velocity, which are still small as compared to the giant resonance frequencies, are briefly reviewed in relation to allowed high angular momenta. It is shown that for the A=150 region, the Coriolis force is dominating for small values (< ∼ 0.05) of the ratio of angular velocity to resonance frequency, whereas the centrifugal force plays a prominent part in the shift of the split resonance energies for larger values of the ratio. Typical examples of the resonance energies and their fragmentation due to both rotation and deformation are given
Measurement of elastic modules of structural ceramic by acoustic resonance
International Nuclear Information System (INIS)
Ahn, Bong Young; Lee Seong Suck; Kim, Young Gil
1993-01-01
Elastic moduli of structural ceramic materials, Al 2 O 3 , SiC, Si 3 N 4 , were measured by acoustic resonance method. Young's modulus, shear modulus, and Poisson's ratio were calculated from the torsional and flexural resonant frequencies, densities, and the dimensions of the specimen. The results by acoustic resonance method were compared with the results by ultrasonic method and the differences were less than 4%.
Interior and exterior resonances in acoustic scattering. pt. 1 - spherical targets
International Nuclear Information System (INIS)
Gaunaurd, G.C.; Tanglis, E.; Uberall, H.; Brill, D.
1983-01-01
In acoustic scattering from elastic objects, resonance features appear in the returned echo at frequencies at which the object's eigenfrequencies are located, which are explained by the excitation of 'interior' creeping waves. Corresponding resonance terms may be split off from the total scattering amplitude, leaving behind an apparently nonresonant background amplitude. This is demonstrated here for scatterers of spherical geometry and in a companion paper also for scatterers of arbitrary geometry, by using the T-matrix approach. For the case of near-impenetrable spheres, it is subsequently shown that the background amplitude can be split further into specularly reflected contributions, plus highly attenuated resonance terms which are explained by the excitation of 'exterior' (Franz-type) creeping waves. The singularity structure of the scattering function is shown mathematically, by using the R-matrix approach of the nuclear-scattering theory, as that of a meromorphic function 'without' any additional 'entire function' (as had been postulated by the singularity expansion method)
Scattering processes and resonances from lattice QCD
Briceño, Raúl A.; Dudek, Jozef J.; Young, Ross D.
2018-04-01
The vast majority of hadrons observed in nature are not stable under the strong interaction; rather they are resonances whose existence is deduced from enhancements in the energy dependence of scattering amplitudes. The study of hadron resonances offers a window into the workings of quantum chromodynamics (QCD) in the low-energy nonperturbative region, and in addition many probes of the limits of the electroweak sector of the standard model consider processes which feature hadron resonances. From a theoretical standpoint, this is a challenging field: the same dynamics that binds quarks and gluons into hadron resonances also controls their decay into lighter hadrons, so a complete approach to QCD is required. Presently, lattice QCD is the only available tool that provides the required nonperturbative evaluation of hadron observables. This article reviews progress in the study of few-hadron reactions in which resonances and bound states appear using lattice QCD techniques. The leading approach is described that takes advantage of the periodic finite spatial volume used in lattice QCD calculations to extract scattering amplitudes from the discrete spectrum of QCD eigenstates in a box. An explanation is given of how from explicit lattice QCD calculations one can rigorously garner information about a variety of resonance properties, including their masses, widths, decay couplings, and form factors. The challenges which currently limit the field are discussed along with the steps being taken to resolve them.
Resonance proton scattering use for the beam parameters control of the electrostatic accelerator
Directory of Open Access Journals (Sweden)
V. I. Soroka
2013-12-01
Full Text Available The paper discusses peculiarities of the resonance proton scattering use for the beam parameters control of the electrostatic accelerators. The expediency of the use has been confirmed by experiment. Peculiarities are caused because elastic resonance scattering through the stage of compound nucleus is always accompanied by potential and Coulomb scattering. These three components interfere and for that reason the resonance form de-pends on a scattering angle and total angular moment of a compound nucleus level. However, possessing neces-sary information in the given field of nuclear spectroscopy enables the selection of resonance with the character-istics suitable for the calibration purpose. Considerable increase of the scattering cross section in the resonance region saves the time and simplifies the experiment technical maintenance. The experiments were performed at the 10 MeV tandem accelerator of the Institute for Nuclear Research, National Academy of Sciences of Ukraine, Kyiv, after its modernization. Silicon and oxygen were used as the targets. Silicon targets were of two types of thickness: 1 the target of complete absorption, 2 the target with the thickness in which the loss of protons ener-gy exceeded the width of the selected resonance. The elastic and non elastic scattering from silicon were used in region of the 3,100 MeV proton energy resonance. Oxygen target, as component of the surface oxidizing layer on beryllium had the thickness which in terms of the loss of proton energy was less than the width of the selected elastic narrow resonance at 3,470 MeV proton energy. As result of the measurement the corrections concerning the energy scale of the accelerator and protons energy spread in the beam were proposed.
Excitation of giant resonances through inelastic scattering
International Nuclear Information System (INIS)
Kailas, S.
1981-01-01
In the last few years, exciting developments have taken place in the study of giant resonances (GR). In addition to the already well known gjant dipole resonance (GDR), the presence of at least two more new GRs viz. giant quadrupole resonance (GQR) and giant monopole resonance (GMR) has been experimentally established. The systematics covering these GRs is found to be consistent with the theoretical expectation. Though the existence of higher multipoles has been predjcted by theory, so far only some of these have been found to be excited experimentally. Various probe particles - electrons, protons (polarized and unpolarized), light and heavy ions and pions - at different bombarding energies have been used to excite the GR region, primarily through the inelastic scattering process. Detailed experiments, looking at the decay modes of GR region, have also been performed. These studies have contributed significantly to a better understanding of the phenomenon of nuclear collective excitation. In this report, the current status of 'GR' research is reviewed. (author)
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...
Elastic scattering of electrons from singly ionized argon
International Nuclear Information System (INIS)
Griffin, D.C.; Pindzola, M.S.
1996-01-01
Recently, Greenwood et al. [Phys. Rev. Lett. 75, 1062 (1995)] reported measurements of large-angle elastic scattering of electrons from singly ionized argon at an energy of 3.3 eV. They compared their results for the differential cross section with cross sections determined using phase shifts obtained from two different scattering potentials and found large discrepancies between theory and experiment at large angles. They state that these differences may be due to the effects of polarization of the target, which are not included in their calculations, as well as inaccurate representations of electron exchange in the local scattering potentials that are employed to determine the phase shifts. In order to test these proposed explanations of the discrepancies, we have carried out calculations of elastic scattering from Ar + using the R-matrix method. We compare both a single-state calculation, which does not include polarization, and a 17-state calculation, in which the effects of dipole polarizability are included through the use of polarization pseudostates within the close-coupling expansion, to each other and with the measurements. We find some differences between the two calculations at intermediate scattering angles, but very close agreement at angles above 100 degree. Although the calculated cross sections agree with experiment between 120 degree and 135 degree, large discrepancies persist at angles above 135 degree. We conclude that the differences between the measurements and theory cannot be explained on the basis of an inaccurate representation of electron exchange or polarization of the target. copyright 1996 The American Physical Society
Spin entanglement in elastic electron scattering from lithium atoms
Bartschat, K.; Santos, S. Fonseca dos
2017-04-01
In two recent papers [Blum and Lohmann, Phys. Rev. Lett. 116, 033201 (2016), 10.1103/PhysRevLett.116.033201; Lohmann et al., Phys. Rev. A 94, 032331 (2016), 10.1103/PhysRevA.94.032331], the possibility of continuously varying the degree of entanglement between an elastically scattered electron and the valence electron of an alkali-metal target was discussed. 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∘-180∘ . The most promising regime for Bell correlations in this particular collision system are energies between about 1.5 and 3.0 eV, in an angular range around 110∘±10∘ . 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.
Covariance Matrix of a Double-Differential Doppler-Broadened Elastic Scattering Cross Section
Arbanas, G.; Becker, B.; Dagan, R.; Dunn, M. E.; Larson, N. M.; Leal, L. C.; Williams, M. L.
2012-05-01
Legendre moments of a double-differential Doppler-broadened elastic neutron scattering cross section on 238U are computed near the 6.67 eV resonance at temperature T = 103 K up to angular order 14. A covariance matrix of these Legendre moments is computed as a functional of the covariance matrix of the elastic scattering cross section. A variance of double-differential Doppler-broadened elastic scattering cross section is computed from the covariance of Legendre moments. Notice: This manuscript has been authored by UT-Battelle, LLC, under contract DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes.
Elastic properties of gamma-Pu by resonant ultrasound spectroscopy
Energy Technology Data Exchange (ETDEWEB)
Migliori, Albert [Los Alamos National Laboratory; Betts, J [Los Alamos National Laboratory; Trugman, A [Los Alamos National Laboratory; Mielke, C H [Los Alamos National Laboratory; Mitchell, J N [Los Alamos National Laboratory; Ramos, M [Los Alamos National Laboratory; Stroe, I [WORXESTER, MA
2009-01-01
Despite intense experimental and theoretical work on Pu, there is still little understanding of the strange properties of this metal. We used resonant ultrasound spectroscopy method to investigate the elastic properties of pure polycrystalline Pu at high temperatures. Shear and longitudinal elastic moduli of the {gamma}-phase of Pu were determined simultaneously and the bulk modulus was computed from them. A smooth linear and large decrease of all elastic moduli with increasing temperature was observed. We calculated the Poisson ratio and found that it increases from 0.242 at 519K to 0.252 at 571K.
Achkar, A J; Sutarto, R; Mao, X; He, F; Frano, A; Blanco-Canosa, S; Le Tacon, M; Ghiringhelli, G; Braicovich, L; Minola, M; Sala, M Moretti; Mazzoli, C; Liang, Ruixing; Bonn, D A; Hardy, W N; Keimer, B; Sawatzky, G A; Hawthorn, D G
2012-10-19
Recently, charge density wave (CDW) order in the CuO(2) planes of underdoped YBa(2)Cu(3)O(6+δ) was detected using resonant soft x-ray scattering. An important question remains: is the chain layer responsible for this charge ordering? Here, we explore the energy and polarization dependence of the resonant scattering intensity in a detwinned sample of YBa(2)Cu(3)O(6.75) with ortho-III oxygen ordering in the chain layer. We show that the ortho-III CDW order in the chains is distinct from the CDW order in the planes. The ortho-III structure gives rise to a commensurate superlattice reflection at Q=[0.33 0 L] whose energy and polarization dependence agrees with expectations for oxygen ordering and a spatial modulation of the Cu valence in the chains. Incommensurate peaks at [0.30 0 L] and [0 0.30 L] from the CDW order in the planes are shown to be distinct in Q as well as their temperature, energy, and polarization dependence, and are thus unrelated to the structure of the chain layer. Moreover, the energy dependence of the CDW order in the planes is shown to result from a spatial modulation of energies of the Cu 2p to 3d(x(2)-y(2)) transition, similar to stripe-ordered 214 cuprates.
Microanalysis of solid surfaces by nuclear reactions and elastic scattering
International Nuclear Information System (INIS)
Agius, B.
1975-01-01
The principles involved in the use of monokinetic light ions beams, of about 1MeV, to the study of surface phenomena are presented. Two complementary techniques are described: the use of elastic scattering, which allows the analysis of impurity elements heavier than the substrate components and the use of nuclear reactions specific of light elements. Typical sensitivities are of the order of 10 11 at/cm 2 in good cases. The depth resolution varies, according to the cases, from about a hundred angstroems to a few thousand angstroems [fr
Elastic electron scattering from the DNA bases cytosine and thymine
International Nuclear Information System (INIS)
Colyer, C. J.; Bellm, S. M.; Lohmann, B.; Blanco, F.; Garcia, G.
2011-01-01
Cross-section data for electron scattering from biologically relevant molecules are important for the modeling of energy deposition in living tissue. Relative elastic differential cross sections have been measured for cytosine and thymine using the crossed-beam method. These measurements have been performed for six discrete electron energies between 60 and 500 eV and for detection angles between 15 deg. and 130 deg. Calculations have been performed via the screen-corrected additivity rule method and are in good agreement with the present experiment.
Mesonic effects in the elastic electron deuteron scattering
International Nuclear Information System (INIS)
Konopka, G.
1981-01-01
The present thesis was concerned with the study of the electromagnetic structure of the deuteron in the framework of the OBE model using elastic electron-deuteron scattering with high momentum transfer. In the framework of the S-matrix formalism the differential cross sections was derived in first Born approximation. The calculation of the invariant amplitude led to the introduction of the electric and magnetic structure functions. From these structure functions the electromagnetic form factor was calculated. Furthermore the effective OBE-potential was derived in the framework of a projection procedure on the base of unitary transformations. (orig./HSI). [de
Theoretical study of the electron-cluster elastic scattering
International Nuclear Information System (INIS)
Descourt, P.; Guet, C.; Farine, M.
1997-01-01
The properties of the clusters consisting of some tens to several hundreds of alkali atoms are generally quite well described in the jellium approximation. This approximation treats the cluster as a charged Fermi liquid of finite size. The optical response predicted by this approximation and taking into account the electron-electron correlations of the Hartree-Fock mean field agrees rather well with the experiment. The objective of this work was to obtain a quantal many-body formalism, within jellium approximation, applicable to elastic scattering of electrons from an alkali-metal-cluster. Influence of correlations on the phase shifts was also taken into account
Parity Non-Conservation in Proton-Proton Elastic Scattering
International Nuclear Information System (INIS)
Brown, V.R.; B.F. Gibson; J.A. Carlson; R. Schiavilla
2002-01-01
The parity non-conserving longitudinal asymmetry in proton-proton (pp) elastic scattering is calculated in the lab-energy range 0-350 MeV using contemporary, realistic strong-interaction potentials combined with a weak-interaction potential comprised of rho- and omega-meson exchanges as exemplified by the DDH model. Values for the rho- and omega-meson coupling constants, h rho rho rho and h rho rho omega , are determined from comparison with the measured asymmetries at 13.6 MeV, 45 MeV, and 221 MeV
Selectron production in quasi-elastic electron-proton scattering
International Nuclear Information System (INIS)
Bartels, J.; Hollik, W.
1985-08-01
We calculate the cross section for the production of selectrons in quasi-elastic electron proton scattering at HERA energies. In the region of very small momentum transfer the cross section turns out to be large: e.g. sigma=36 pb for a selectron mass of 60 GeV, tsub(min) 2 ), and photino mass small compared to the selectron mass. Together with the clean experimental signature, this large cross section makes the reaction e+P->e+γ tilde+P one of the most promising HERA-processes in connection with the search for supersymmetric particles. (orig.)
Quasi-elastic and inelastic inclusive electron scattering from an oxygen jet target
International Nuclear Information System (INIS)
Anghinolfi, M.; Cenni, R.; Levi Sandri, P.; Longhi, A.; Mokeev, V.I.; Polli, E.; Reolon, A.; Ricco, G.; Simula, S.; Taiuti, M.; Teglia, A.; Zucchiatti, A.
1996-01-01
The results of an experiment on inclusive electron scattering from an oxygen jet target, performed in a wide range of energy and momentum transfer covering both quasi-elastic and Δ(1232) resonance regions, are reported. In the former region the theoretical predictions, obtained including effects of nucleon-nucleon correlations in both initial and final states, give a good description of the experimental data. In the inelastic region a broadening as well as a damping of the resonant part of the cross section with respect to the free nucleon case is observed. The need of more detailed calculations including nuclear structure effects on the electroproduction cross section of nucleon resonances is highlighted. (orig.)
Creation of X-Ray Transparency of Matter by Stimulated Elastic Forward Scattering.
Stöhr, J; Scherz, A
2015-09-04
X-ray absorption by matter has long been described by the famous Beer-Lambert law. Here, we show how this fundamental law needs to be modified for high-intensity coherent x-ray pulses, now available at x-ray free electron lasers, due to the onset of stimulated elastic forward scattering. We present an analytical expression for the modified polarization-dependent Beer-Lambert law for the case of resonant core-to-valence electronic transitions and incident transform limited x-ray pulses. Upon transmission through a solid, the resonant absorption and dichroic contrasts are found to vanish with increasing x-ray intensity, with the stimulation threshold lowered by orders of magnitude through a resonant superradiantlike effect. Our results have broad implications for the study of matter with x-ray lasers.
α4He elastic scattering at high energies
International Nuclear Information System (INIS)
Usmani, A.A.; Usmani, Q.N.
1988-03-01
Differential cross sections for α 4 He elastic scattering have been calculated at incident α particle momenta of 4.32, 5.07 and 7.0 GeV/c within the framework of the Glauber multiple scattering theory. The full Glauber amplitude is calculated using the Monte Carlo method for evaluating multidimensional integrals. We find that, in general, the more realistic double Gaussian model for the density brings theory closer to experiment as compared to the generally used single Gaussian model. Our results with the double Gaussian model are in fairly good agreement with the experimented data at 4.32 and 5.07 GeV/c. (author). 11 refs, 4 figs, 1 tab
Vector analyzing power in elastic electron-proton scattering
International Nuclear Information System (INIS)
Diaconescu, L.; Ramsey-Musolf, M.J.
2004-01-01
We compute the vector analyzing power (VAP) for the elastic scattering of transversely polarized electrons from protons at low energies using an effective theory of electrons, protons, and photons. We study all contributions through second order in E/M, where E and M are the electron energy and nucleon mass, respectively. The leading-order VAP arises from the imaginary part of the interference of one- and two-photon exchange amplitudes. Subleading contributions are generated by the nucleon magnetic moment and charge radius as well as recoil corrections to the leading-order amplitude. Working to O(E/M) 2 , we obtain a prediction for A n that is free of unknown parameters and that agrees with the recent measurement of the VAP in backward angle ep scattering
Parity Violation in Forward Angle Elastic Electron-Proton Scattering
Energy Technology Data Exchange (ETDEWEB)
Miller, IV, Grady Wilson [Princeton Univ., NJ (United States)
2001-01-01
We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from the proton at Jefferson Laboratory. The kinematic point (θ_{lab} = 12.3 deg. and (Q^{2}) = 0.48 (GeV/c)^{2}) is chosen to provide sensitivity to the strange electric form factor G^{s}_{E}. A 3.36 GeV beam of longitudinally polarized electrons was scattered from protons in a liquid hydrogen target. The scattered flux was detected by a pair of spectrometers which focussed the elastically-scattered electrons onto total-absorption detectors. The detector signals were integrated and digitized by a custom data acquisition system. A feedback system reduced systematic errors by controlling helicity-correlated beam intensity differences at the sub-ppm (part per million) level. The experimental result, A = 14.5 +/- 2.0 (stat) ± 1.1 (syst) ppm, is consistent with the electroweak Standard Model with no additional contributions from strange quarks. In particular, the measurement implies G^{S}_{E} + 0.39 G^{s}_{M} = 0.023 ± 0.040 ± 0.026 (ζG^{n}_{E}), where the last uncertainty is due to the estimated uncertainty in the neutron electric form factor G^{n}_{E} . This result represents the first experimental constraint of the strange electric form factor.
Direct sampling methods for inverse elastic scattering problems
Ji, Xia; Liu, Xiaodong; Xi, Yingxia
2018-03-01
We consider the inverse elastic scattering of incident plane compressional and shear waves from the knowledge of the far field patterns. Specifically, three direct sampling methods for location and shape reconstruction are proposed using the different component of the far field patterns. Only inner products are involved in the computation, thus the novel sampling methods are very simple and fast to be implemented. With the help of the factorization of the far field operator, we give a lower bound of the proposed indicator functionals for sampling points inside the scatterers. While for the sampling points outside the scatterers, we show that the indicator functionals decay like the Bessel functions as the sampling point goes away from the boundary of the scatterers. We also show that the proposed indicator functionals continuously dependent on the far field patterns, which further implies that the novel sampling methods are extremely stable with respect to data error. For the case when the observation directions are restricted into the limited aperture, we firstly introduce some data retrieval techniques to obtain those data that can not be measured directly and then use the proposed direct sampling methods for location and shape reconstructions. Finally, some numerical simulations in two dimensions are conducted with noisy data, and the results further verify the effectiveness and robustness of the proposed sampling methods, even for multiple multiscale cases and limited-aperture problems.
Whispering gallery modes for elastic waves in disk resonators
Directory of Open Access Journals (Sweden)
S. Kaproulias
2011-12-01
Full Text Available The resonant modes of elastic waves in disk resonators are computationally studied with the finite difference time domain method. Different materials examined for the disk such as platinum and silicon. The effect of a glass substrate is also important especially in the case of silicon disks because of the similarity of sound velocities and mass densities between the two materials. The possibility of using those structures as sensors is also considered.
Impact picture and internal matter motion for elastic scattering
International Nuclear Information System (INIS)
Bourrely, C.; Soffer, J.; Wu, T.T.
1978-01-01
Since four-dimensional relativistic quantum field theories have all the desirable properties such as particle production, unitarity, and analyticity, they provide a useful way to gain theoretical knowledge not only for weak and electromagnetic processes but also for strong interactions. For the dynamics of strong interactions, because of the necessity of understanding all orders of perturbation theory, the simplest case is the high energy limit. After a brief review of the general features of elastic scattering in field theories, the need of developing a phenomenology in order to make contact with present and future experimental data is discussed. Such a phenomenology must satisfy the dual requirement of, on the one hand, giving an accurate description of hadronic experimental data at high energies and, on the other hand, having the s → infinity behavior obtained from field theories. Recent improvements on such a phenomenology are emphasized, and include better parametrization and proper Regge background and spin effects. In particular, the spin of the proton is taken into account by using the concept of hadronic matter current of Chou and Yang. In addition to the total and differential cross sections for ISABELLE energies, predictions are obtained for both polarization and R parameters for proton--proton elastic scattering. Sore theoretical problems for the future are outlined
Purely elastic scattering theories and their ultraviolet limits
International Nuclear Information System (INIS)
Klassen, T.R.; Chicago Univ., IL; Melzer, E.
1990-01-01
We use the thermodynamic Bethe ansatz to find the finite-size corrections to the ground-state energy in an arbitrary (1+1)-dimensional purely elastic scattering theory. The leading finite-size effects are characterized by tilde c=c-12d 0 , where c and d 0 are the central charge and the lowest scaling dimension, respectively, of the (possibly nonunitary) CFT describing the ultraviolet limit of the massive scattering theory. After presenting the purely elastic S-matrix theories that emerged in recent discussions of perturbed CFTs, we calculate their finite-size scaling coefficient tilde c. Our results show that the UV limits of the 'minimal' S-matrix theories are the unperturbed CFTs in question. On the other hand, the S-matrices which have been suggested to describe affine Toda field theories, differing from the minimal S-matrices by coupling-dependent factors, are seen to have free bosonic CFTs as their UV limits. We also discuss some interesting properties of tilde c. In particular, we suggest that tilde c is a measure of the number of degrees of freedom of an arbitrary two-dimensional CFT. (orig.)
Magnetic effects in the paraxial regime of elastic electron scattering
Edström, Alexander; Lubk, Axel; Rusz, Ján
2016-11-01
Motivated by a recent claim [Phys. Rev. Lett. 116, 127203 (2016), 10.1103/PhysRevLett.116.127203] that electron vortex beams can be used to image magnetism at the nanoscale in elastic scattering experiments, using transmission electron microscopy, a comprehensive computational study is performed to study magnetic effects in the paraxial regime of elastic electron scattering in magnetic solids. Magnetic interactions from electron vortex beams, spin polarized electron beams, and beams with phase aberrations are considered, as they pass through ferromagnetic FePt or antiferromagnetic LaMnAsO. The magnetic signals are obtained by comparing the intensity over a disk in the diffraction plane for beams with opposite angular momentum or aberrations. The strongest magnetic signals are obtained from vortex beams with large orbital angular momentum, where relative magnetic signals above 10-3 are indicated for 10 ℏ orbital angular momentum, meaning that relative signals of one percent could be expected with the even larger orbital angular momenta, which have been produced in experimental setups. All results indicate that beams with low acceleration voltage and small convergence angles yield stronger magnetic signals, which is unfortunately problematic for the possibility of high spatial resolution imaging. Nevertheless, under atomic resolution conditions, relative magnetic signals in the order of 10-4 are demonstrated, corresponding to an increase with one order of magnitude compared to previous work.
Two-photon exchange in elastic electron-nucleon scattering
International Nuclear Information System (INIS)
Blunden, P.G.; Melnitchouk, W.; Tjon, J.A.
2005-01-01
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, G E /G M . The two-photon exchange contribution to the longitudinal polarization transfer P L is small, whereas the contribution to the transverse polarization transfer P T is enhanced at backward angles by several percent, increasing with Q 2 . This gives rise to a small, E /G M obtained from the polarization transfer ratio P T /P L at large Q 2 . We also compare the two-photon exchange effects with data on the ratio of e + p to e - 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 3 He form factors
Study on the 3H + α and 3He + α elastic scatterings in a state with zero orbital moment
International Nuclear Information System (INIS)
Chopovskij, L.L.
1988-01-01
The asymptotics of the wave function of the relative motion of clusters is constructed at zero interaction energy. The set of equations of the resonating-group method (RGM) algebraic version is transformed to the zero energy limit of the relative motion of clusters. The equations obtained are used to calculate the 3 H + α and 3 He + α scattering lengths in the one-channel RGM approximation. The theory predicts large values of the scattering lengths for the elastic scattering of light charged clusters: ∼10 + 23Fm for the 3 H + α channel, and ∼30 + 82Fm for the 3 He + α channel
Interference scattering effects on intermediate resonance absorption at operating temperatures
International Nuclear Information System (INIS)
Goldstein, R.
1975-01-01
Resonance integrals may be accurately calculated using the intermediate resonance (IR) approximation. Results are summarized for the case of an absorber with given potential scattering cross sections and interference scattering parameter admixed with a non absorbing moderator of given cross section and located in a narrow resonance moderating medium. From the form of the IR solutions, it is possible to make some general observations about effects of interference scattering on resonance absorption. 2 figures
Li, Jun; Zhang, Song Bin; Ye, Bang Jiao; Wang, Jian Guo; Janev, R. K.
2017-09-01
Low-energy electron elastic scattering and impact ionization with hydrogenlike helium in Debye plasmas have been investigated by employing the exterior complex scaling method. The interactions between charged particles in the plasmas have been represented by Debye-Hückel potentials. The 1 s -1 s elastic collision strengths below the n =2 excitation threshold of He+ dominated by resonance structures are calculated for different screening lengths. As the screening strength increases, the resonance peaks studied [2(1,0) 2 +1Se,3Po,1De , and 2(0,1) 2 +1Po] exhibit blueshifts and then redshifts with a further increase of the screening strength, which results in dramatic changes of the collision strengths. It is found that these dynamic variation features of the resonances are related to the changes of energy levels of He+ in the screened potential and geometric configurations of resonances. Triple-differential-ionization cross sections in coplanar geometries at 6-Ry incident electron energy are also reported, significant changes are observed with varying screening length.
Proton compton scattering in the resonance region
International Nuclear Information System (INIS)
Ishii, Takanobu.
1979-12-01
Differential cross sections of the proton Compton scattering have been measured in the energy range between 400 and 1150 MeV at CMS angles of 130 0 , 100 0 and 70 0 . The recoil proton was detected with a magnetic spectrometer using multi-wire proportional chambers and wire spark chambers. In coincidence with the proton, the scattered photon was detected with a lead glass Cerenkov counter of the total absorption type with a lead plate converter, and horizontal and vertical scintillation counter hodoscopes. The background due to the neutral pion photoproduction, was subtracted by using the kinematic relations between the scattered photon and the recoil proton. Theoretical calculations based on an isobar model with two components, that is, the resonance plus background, were done, and the photon couplings of the second resonance region were determined firstly from the proton Compton data. The results are that the helicity 1/2 photon couplings of P 11 (1470) and S 11 (1535), and the helicity 3/2 photon coupling of D 13 (1520) are consistent with those determined from the single pion photoproduction data, but the helicity 1/2 photon coupling of D 13 (1520) has a somewhat larger value than that from the single pion photoproduction data. (author)
Fast-neutron elastic scattering from elemental vanadium
International Nuclear Information System (INIS)
Smith, A.B.; Guenther, P.T.; Lawson, R.D.
1988-03-01
Differential neutron elastic- and inelastic-scattering cross sections of vanadium were measured from 4.5 to 10 MeV. These results were combined with previous 1.5 to 4.0 MeV data from this laboratory, the 11.1 MeV elastic-scattering results obtained at Ohio University, and the reported neutron total cross sections to energies of ∼20.0 MeV, to form a data base which was interpreted in terms of the spherical optical-statistical model. A fit to the data was achieved by making both the strengths and geometries of the optical-model potential energy dependent. This energy dependence was large below ∼6.0 MeV. Above ∼6.0 MeV the energy dependencies are smaller, and similar to those characteristic of global models. Using the dispersion relationship and the method of moments, the optical-model potential energy deduced from 0.0 to 11.1 MeV neutron-scattering data was extrapolated to higher energies and to the bound-state regime. This extrapolation leads to predicted neutron total cross sections that are within 3% of the experimental values throughout the energy range 0.0 to 20.0 MeV. Furthermore, the values of the volume-integral-per-nucleon of the real potential are in excellent agreement with those needed to reproduce the observed binding energies of particle- and hole-states. The latter gives clear evidence of the Fermi surface anomaly. Using only the 0.0 to 11.1 MeV data, the predicted E < O behavior of the strength and radius of the real shell-model Woods-Saxon potential are somewhat different from those obtained by Mahaux and Sartor in their analysis of nuclei near closed shells. 61 refs., 9 figs., 2 tabs
Electron and positron atomic elastic scattering cross sections
International Nuclear Information System (INIS)
Stepanek, Jiri
2003-01-01
A method was developed to calculate the total and differential elastic-scattering cross sections for incident electrons and positrons in the energy range from 0.01 eV to 1 MeV for atoms of Z=1-100. For electrons, hydrogen, helium, nitrogen, oxygen, krypton, and xenon, and for positrons, helium, neon, and argon atoms were considered for comparison with experimental data. First, the variationally optimized atomic static potentials were calculated for each atom by solving the Dirac equations for bound electron states. Second, the Dirac equations for a free electron or positron are solved for an atom using the previously calculated static potential accomplished (in the case of electrons) by 'adjusted' Hara's exchange potential for a free-state particle. Additional to the exchange effects, the charge cloud polarization effects are considered applying the correlation-polarization potential of O'Connell and Lane (with correction of Padial and Norcross) for incident electrons, and of Jain for incident positrons. The total, cutoff and differential elastic-scattering cross sections are calculated for incident electrons and positrons with the help of the relativistic partial wave analysis. The solid state effects for scattering in solids are described by means of a muffin-tin model, i.e. the potentials of neighboring atoms are superpositioned in such a way that the resulting potential and its derivative are zero in the middle distance between the atoms. The potential of isolated atom is calculated up to the radius at which the long-range polarization potential becomes a value of -10 -8
Pion elastic and inelastic scattering from 15N
International Nuclear Information System (INIS)
Saunders, D.P.
1991-12-01
Data were obtained on the Clinton P. Anderson Los Alamos Meson Physics Facility Energetic Pion Channel and Spectrometer for elastic and inelastic pion scattering from ground state 15 N nuclei. States observed here included those of 0.0, 5.27, 6.32, 7.16, 7.30, 7.57, 8.31, 8.57, 9.15, 9.76, 9.9, 10.7, 11.3, 11.9, 12.5, 12.9, 13.1, 14.1, 14.4, 14.6, 15.0, 16.5, 16.9, 17.2, 17.6, 18.3, 18.7, and 18.9 MeV excitation energies. Angular distributions were obtained for scattering at angles from 25 degree to 90 degree in 5 degree increments with an incident pion energy of 164 MeV. Optical model analyses of the elastic (0 MeV) angular distributions with equal point proton and neutron densities in both momentum and coordinate space formulations accurately predict the data, although the two formulations require different energy shifts to do so. This difference is thought to be a result of the more accurate nonlocal representation of the nuclear potential in the momentum space code. Additional spectra were obtained for scattering at constant momentum transfers of .94 and 1.57 fm -1 in order to generate constant momentum transfer excitation functions. Use of these excitation functions, σ(π + )/σ(π - ) ratios, and shell model DWIA calculations allowed identification of several excited states having shell-model-like, single particle-hole, pure spin-flip excitations. Shell model and collective model DWIA calculations, as well as the q = .94 and 1.57 fm -1 excitation functions and the σ(π + )/σ(π - ) ratios indicate that the other states are generally well represented by a shell model description with collective enhancements
Position calibration of silicon strip detector using quasi-elastic scattering of 16O+197Au
International Nuclear Information System (INIS)
Yan Wenqi; Hu Hailong; Zhang Gaolong
2013-01-01
Background: Elastic scattering is induced by weakly unstable nuclei. Generally, a good angular resolution for angular distribution of elastic scattering is needed. The silicon strip detector is often used for this kind of experiment. Purpose: In order to use silicon strip detector to study the elastic scattering of weakly unbound nuclei, it is important to get the information of its position calibration. It is well known that the elastic scattering of stable nuclei has a good angular distribution and many experimental data have been obtained. Methods: So the scattering of stable nuclei can be used to calibrate the position information of silicon strip detector. In this experiment, the positions of silicon strip detectors are calibrated using 101 MeV and 59 MeV 16 O scattering on the 197 Au target. Results: The quasi-elastic peaks can be observed in the silicon strip detectors and the counts of quasi-elastic 16 O can be obtained. The solid angles of the silicon strip detectors are calibrated by using alpha source which has three alpha energy values. The angular distribution of quasi-elastic scattering of 16 O+ 197 Au is obtained at these two energy values. Conclusions: The experimental data of angular distribution are reasonable and fit for the principle of angular distribution of elastic scattering. It is concluded that in the experiment these silicon strip detectors can accurately give the position information and can be used for the elastic scattering experiment. (authors)
Heavy ion elastic and quasi-elastic scattering above E/A = 30 MeV
International Nuclear Information System (INIS)
Barrette, J.
1986-05-01
At high energy, heavy-ion elastic scattering probes the ion-ion potential in a large domain much inside the strong absorption radius. This results in a more precise determination of the real part of the nuclear potential and a consistent picture of its evolution with energy begins to emerge. It is relatively similar to that observed in light ion scattering. Even if the inelastic angular distributions seem to contain less refractive or interior contribution, coupled channel effects from these states are still important at least up to 20 MeV/n. Heavy-ion induced transfer reactions to discrete states have small cross sections but present a very strong selectivity for states with the highest available spin and could thus provide new and interesting spectroscopic information
8B + 208Pb Elastic Scattering at Coulomb Barrier Energies
La Commara, M.; Mazzocco, M.; Boiano, A.; Boiano, C.; Manea, C.; Parascandolo, C.; Pierroutsakou, D.; Signorini, C.; Strano, E.; Torresi, D.; Yamaguchi, H.; Kahl, D.; Di Meo, P.; Grebosz, J.; Imai, N.; Hirayama, Y.; Ishiyama, H.; Iwasa, N.; Jeong, S. C.; Jia, H. M.; Kim, Y. H.; Kimura, S.; Kubono, S.; Lin, C. J.; Miyatake, H.; Mukai, M.; Nakao, T.; Nicoletto, M.; Sakaguchi, Y.; Sánchez-Benítez, A. M.; Soramel, F.; Teranishi, T.; Wakabayashi, Y.; Watanabe, Y. X.; Yang, L.; Yang, Y. Y.
2018-02-01
The scattering process of weakly-bound nuclei at Coulomb barrier energies provides deep insights on the reaction dynamics induced by exotic nuclei. Within this framework, we measured for the first time the scattering process of the short-lived Radioactive Ion Beam (RIB) 8B (Sp = 0.1375 MeV) from a 208Pb target at 50 MeV beam energy. The 8B RIB was produced by means of the in-flight facility CRIB (RIKEN, Japan) with an average intensity on target of 10 kHz and a purity about 25%. Elastically scattering ions were detected in the angular range θc.m. = 10°-160° by means of the detector array EXPADES. A preliminary optical model analysis indicates a total reaction cross section of about 1 b, a value, once reduced, 2-3 times larger than those obtained for the reactions induced by the stable weakly-bound projectiles 6,7Li on a 208Pb target in the energy range around the Coulomb barrier.
Resonance effects in neutron scattering lengths
Energy Technology Data Exchange (ETDEWEB)
Lynn, J.E.
1989-06-01
The nature of neutron scattering lengths is described and the nuclear effects giving rise to their variation is discussed. Some examples of the shortcomings of the available nuclear data base, particularly for heavy nuclei, are given. Methods are presented for improving this data base, in particular for obtaining the energy variation of the complex coherent scattering length from long to sub-/angstrom/ wave lengths from the available sources of slow neutron cross section data. Examples of this information are given for several of the rare earth nuclides. Some examples of the effect of resonances in neutron reflection and diffraction are discussed. This report documents a seminar given at Argonne National Laboratory in March 1989. 18 refs., 18 figs.
Resonance effects in neutron scattering lengths
International Nuclear Information System (INIS)
Lynn, J.E.
1989-01-01
The nature of neutron scattering lengths is described and the nuclear effects giving rise to their variation is discussed. Some examples of the shortcomings of the available nuclear data base, particularly for heavy nuclei, are given. Methods are presented for improving this data base, in particular for obtaining the energy variation of the complex coherent scattering length from long to sub-angstrom wave lengths from the available sources of slow neutron cross section data. Examples of this information are given for several of the rare earth nuclides. Some examples of the effect of resonances in neutron reflection and diffraction are discussed. This report documents a seminar given at Argonne National Laboratory in March 1989. 18 refs., 18 figs
Modelling Elastic Scattering and Light Transport in 3D Collagen Gel Constructs
National Research Council Canada - National Science Library
Bixio, L
2001-01-01
A model of elastic scattering and light propagation is presented, which can be used to obtain the scattering coefficient, the index of refraction and the distribution of the collagen fibrils in a gel...
Nazarov, Vladimir U.; Silkin, Vyacheslav M.; Krasovskii, Eugene E.
2017-12-01
Inelastic scattering of the medium-energy (˜10 -100 eV) electrons underlies the method of the high-resolution electron energy-loss spectroscopy (HREELS), which has been successfully used for decades to characterize pure and adsorbate-covered surfaces of solids. With the emergence of graphene and other quasi-two-dimensional (Q2D) crystals, HREELS could be expected to become the major experimental tool to study this class of materials. We, however, identify a critical flaw in the theoretical picture of the HREELS of Q2D crystals in the context of the inelastic scattering only ("energy-loss functions" formalism), in contrast to its justifiable use for bulk solids and surfaces. The shortcoming is the neglect of the elastic scattering, which we show is inseparable from the inelastic one, and which, affecting the spectra dramatically, must be taken into account for the meaningful interpretation of the experiment. With this motivation, using the time-dependent density functional theory for excitations, we build a theory of the simultaneous inelastic and elastic electron scattering at Q2D crystals. We apply this theory to HREELS of graphene, revealing an effect of the strongly coupled excitation of the π +σ plasmon and elastic diffraction resonances. Our results open a path to the theoretically interpretable study of the excitation processes in crystalline mesoscopic materials by means of HREELS, with its supreme resolution on the meV energy scale, which is far beyond the capacity of the now overwhelmingly used EELS in transmission electron microscopy.
Energy evolution of the large-t elastic scattering and its correlation with multiparticle production
International Nuclear Information System (INIS)
Troshin, S. M.
2013-01-01
It is emphasized that the collective dynamics associated with color confinement is dominating over a point-like mechanism related to a scattering of the proton constituents at the currently available values of the momentum transferred in proton elastic scattering at the LHC. Deep-elastic scattering and its role in the dissimilation of the absorptive and reflective asymptotic scattering mechanisms are discussed with emphasis on the experimental signatures associated with the multiparticle production processes.
Energy evolution of the large-t elastic scattering and its correlation with multiparticle production
Energy Technology Data Exchange (ETDEWEB)
Troshin, S. M. [Institute for High Energy Physics, Protvino, Moscow Region, 142281 (Russian Federation)
2013-04-15
It is emphasized that the collective dynamics associated with color confinement is dominating over a point-like mechanism related to a scattering of the proton constituents at the currently available values of the momentum transferred in proton elastic scattering at the LHC. Deep-elastic scattering and its role in the dissimilation of the absorptive and reflective asymptotic scattering mechanisms are discussed with emphasis on the experimental signatures associated with the multiparticle production processes.
Resonances, scattering theory and rigged Hilbert spaces
International Nuclear Information System (INIS)
Parravicini, G.; Gorini, V.; Sudarshan, E.C.G.
1979-01-01
The problem of decaying states and resonances is examined within the framework of scattering theory in a rigged Hilbert space formalism. The stationary free, in, and out eigenvectors of formal scattering theory, which have a rigorous setting in rigged Hilbert space, are considered to be analytic functions of the energy eigenvalue. The value of these analytic functions at any point of regularity, real or complex, is an eigenvector with eigenvalue equal to the position of the point. The poles of the eigenvector families give origin to other eigenvectors of the Hamiltonian; the singularities of the out eigenvector family are the same as those of the continued S matrix, so that resonances are seen as eigenvectors of the Hamiltonian with eigenvalue equal to their location in the complex energy plane. Cauchy theorem then provides for expansions in terms of complete sets of eigenvectors with complex eigenvalues of the Hamiltonian. Applying such expansions to the survival amplitude of a decaying state, one finds that resonances give discrete contributions with purely exponential time behavior; the background is of course present, but explicitly separated. The resolvent of the Hamiltonian, restricted to the nuclear space appearing in the rigged Hilbert space, can be continued across the absolutely continuous spectrum; the singularities of the continuation are the same as those of the out eigenvectors. The free, in and out eigenvectors with complex eigenvalues and those corresponding to resonances can be approximated by physical vectors in the Hilbert space, as plane waves can. The need for having some further physical information in addition to the specification of the total Hamiltonian is apparent in the proposed framework. The formalism is applied to the Lee-Friedrichs model. 48 references
Vibrationally elastic and inelastic scattering of electrons by hydrogen sulphide molecules
International Nuclear Information System (INIS)
Nishimura, Tamio; Itikawa, Yukikazu
1996-01-01
Vibrationally elastic and inelastic cross sections (differential and integral ones) are calculated for electron scattering from hydrogen sulphide (H 2 S) at the collision energies 3-30 eV. Vibrational excitation of all three fundamental modes is considered. The calculation is based on the rotationally sudden and a vibrationally close-coupling method using an ab initio electrostatic potential. The effects of electron exchange and target polarization are taken into account approximately. The resulting cross sections are compared with the experimental data available. The present differential cross sections (DCS) for the elastic scattering reproduce the experimental data well. For the inelastic scattering, the present DCS is too small at 3 eV, compared with the experimental data. This is probably due to a shape resonance, which the present calculation would not be sufficiently accurate to produce. In the higher energy region (i.e. above about 10 eV), the present vibrational cross section should be more reliable, but no experimental data are available so far. (Author)
International Nuclear Information System (INIS)
Lesiak, B.; Kosinski, A.; Nowakowski, R.; Koever, L.; Toth, J.; Varga, D.; Cserny, I.; Sulyok, A.; Gergely, G.
2006-01-01
Complete text of publication follows. Elastic peak electron spectroscopy (EPES) deals with the interaction of electrons with atoms of a solid surface, studying the distribution of electrons backscattered elastically. The nearest vicinity of the elastic peak, (low kinetic energy region) reflects both, electron inelastic and quasi-elastic processes. The incident electrons produce surface excitations, inducing surface plasmons with the corresponding loss peaks separated by 1 - 20 eV energy from the elastic peak. Quasi-elastic losses result from the recoil of scattering atoms of different atomic number, Z. The respective energy shift and Doppler broadening of the elastic peak depend on Z, the primary electron energy, E, and the measurement geometry. Quantitative surface analytical application of EPES, such as determination of parameters describing electron transport, requires a comparison of experimental data with corresponding data derived from Monte Carlo (MC) simulation. Several problems occur in EPES studies of polymers. The intensity of elastic peak, considered in quantitative surface analysis, is influenced by both, the inelastic and quasi-elastic scattering processes (especially for hydrogen scattering atoms and primary electron energy above 1000 eV). An additional factor affecting the elastic peak intensity is the surface morphology and roughness. The present work compares the effect of these factors on the elastic peak intensity for selected polymers (polyethylene, polyaniline and polythiophenes). X-ray photoelectron spectroscopy (XPS) and helium pycnometry are applied for deriving the surface atomic composition and the bulk density, while scanning electron microscopy (SEM) and atomic force microscopy (AFM) for determining surface morphology and roughness. According to presented results, the influence of surface morphology and roughness is larger than those of surface excitations or recoil of hydrogen atoms. The component due to recoil of hydrogen atoms can be
Inclusive production of large-p/sub T/ protons and quark-quark elastic scattering
International Nuclear Information System (INIS)
Chen, C.K.
1978-01-01
A proton-formation process in combination with hard quark-quark scattering is capable of explaining the observed large-p/sub T/ single-proton inclusive production data. This model implies that the inclusive production of two large-p/sub T/ protons at opposite directions is dominated by large-angle elastic scattering of two up quarks, and becomes an ideal place to study elastic quark-quark scattering. This two-proton inclusive production process is also ideal for the study of the spin structure of quark-quark elastic scattering, so the assumptions of pure vector-type quark-quark interaction and of colored quarks can be checked empirically. The consistency of applying the quark-elastic-scattering idea to large-angle elastic proton-proton scattering and to the inclusive production of large-p/sub T/ protons is also demonstrated
Spin asymmetries for elastic scattering in krypton at intermediate energies
International Nuclear Information System (INIS)
Went, M R; McEachran, R P; Lohmann, Birgit; MacGillivray, W R
2002-01-01
Measurements of the spin asymmetry for elastic scattering of spin-polarized electrons from krypton are presented, for incident energies in the range 20-200 eV. The measured spin asymmetries are generally small, and do not exceed 0.25 in magnitude at any energy or angle. The experimental results are compared with calculated values of the Sherman function, obtained by solution of the Dirac-Fock equations. The calculations have been performed with the inclusion of polarization and dynamic distortion potentials, and with the addition of an absorption potential to model inelastic processes. For incident energies of 50, 60 and 65 eV, the calculated values of the Sherman function are shown to be extremely sensitive to the details of the model, with the addition of the absorption potential producing dramatically different results
p-barp elastic scattering at high energies
International Nuclear Information System (INIS)
Padua, A.B. de.
1986-01-01
The p-bar p elastic scattering is analysed in the energy range 9.78 pp werefitted under the hypothesis of a pure imaginary amplitude and writted as a sum of exponentials, that is, a(s,t) = a(s,O) Σ n i=l α i exp β i t. Using the parameters a(s,O), α i and β i we obtained the absorption constante K- pp , the form factor and the mean square radius of the - p matter distribution by the Chou-Yang model. These calculations reveal a dip around -t ≅ 1.3 (GeV/c) 2 at 31 and 62 GeV. (author) [pt
Elastic scattering, fusion, and breakup of light exotic nuclei
Energy Technology Data Exchange (ETDEWEB)
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.)
np Elastic-scattering experiments with polarized neutron beams
International Nuclear Information System (INIS)
Chalmers, J.S.; Ditzler, W.R.; Hill, D.
1985-01-01
Measurements of the spin transfer parameters, K/sub NN/ and K/sub LL/, at 500, 650, and 800 MeV are presented for the reaction p-vector d → n-vector pp at 0 0 . The data are useful input to the NN data base and indicate that the quasi-free charge exchange (CEX) reaction is a useful mechanism for producing neutrons with at least 40% polarization at energies as low as 500 MeV. Measurements of np elastic scattering observables C/sub LL/ and C/sub SL/ covering 35 0 to 172 0 are performed using a polarized neutron beam at 500, 650, and 800 MeV. Preliminary results are presented. 3 refs., 6 figs
Analysis of elastic scattering at low momentum transfer
International Nuclear Information System (INIS)
Pumplin, J.
1991-11-01
A method for analyzing high energy elastic scattering data is described, which improves on previous methods to extract σ tot , σ el , B, and ρ=ReM(0)/ImM(0) from experiment by properly allowing for the curvature of 1ndσ/dt with t. The method is used to make a critical analysis of data at √s=19.4, 546, and 1800 GeV. It is found that previous analyses systematically underestimate the forward slope B. The large value of ρ obtained by UA4 at √s=546 GeV is shown to be doubtful. The method described here should aid in the analysis of forthcoming data from UA4/2 and E710. (orig.)
Detection of supernova neutrinos by neutrino-proton elastic scattering
International Nuclear Information System (INIS)
Beacom, John F.; Farr, Will M.; Vogel, Petr
2002-01-01
We propose that neutrino-proton elastic scattering, ν+p→ν+p, can be used for the detection of supernova neutrinos in scintillator detectors. Though the proton recoil kinetic energy spectrum is soft, with T p ≅2E ν 2 /M p , and the scintillation light output from slow, heavily ionizing protons is quenched, the yield above a realistic threshold is nearly as large as that from ν(bar sign) e +p→e + +n. In addition, the measured proton spectrum is related to the incident neutrino spectrum, which solves a long-standing problem of how to separately measure the total energy and temperature of ν μ , ν τ , ν(bar sign) μ , and ν(bar sign) τ . The ability to detect this signal would give detectors like KamLAND and Borexino a crucial and unique role in the quest to detect supernova neutrinos
Elliptic flow from Coulomb interaction and low density elastic scattering
Sun, Yuliang; Li, Qingfeng; Wang, Fuqiang
2018-04-01
In high energy heavy ion collisions and interacting cold atom systems, large elliptic flow anisotropies have been observed. For the large opacity (ρ σ L ˜103 ) of the latter hydrodynamics is a natural consequence, but for the small opacity (ρ σ L ˜1 ) of the former the hydrodynamic description is questionable. To shed light onto the situation, we simulate the expansion of a low density argon ion (or atom) system, initially trapped in an elliptical region, under the Coulomb interaction (or elastic scattering). Significant elliptic anisotropy is found in both cases, and the anisotropy depends on the initial spatial eccentricity and the density of the system. The results may provide insights into the physics of anisotropic flow in high energy heavy ion collisions and its role in the study of quantum chromodynamics.
Effect of the Pauli principle in elastic scattering
International Nuclear Information System (INIS)
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
np elastic scattering analyzing power characteristics at intermediate energies
International Nuclear Information System (INIS)
Abegg, R.; Davis, C.A.; Delheij, P.P.J.; Green, P.W.; Greeniaus, L.G.; Healey, D.C.; Miller, C.A.; Rodning, N.L.; Wait, G.D.; Ahmad, M.; Cairns, E.B.; Coombes, G.H.; Lapointe, C.; McDonald, W.J.; Moss, G.A.; Roy, G.; Soukup, J.; Tkachuk, R.R.; Ye, Y.; Watson, J.W.
1989-06-01
Recent measurements of charge symmetry breaking in the np system at 477 MeV, and of A oonn for np elastic scattering at 220, 325 and 425 MeV also yield accurate analyzing power data. These data allow the energy dependence of the analyzing power zero-crossing angle and the slope of the analyzing power at the zero-crossing to be determined. The incident neutron energies span a region where the zero-crossing angle is strongly energy dependent (Ε n n > 350 MeV). The results are compared to current phase shift analysis predictions, recently published LAMPF data, and the predictions of the Bonn and Paris potentials. (Author) 13 refs., 2 tabs., 2 figs
Elastic and inelastic electron scattering on tensor polarized deuteron
International Nuclear Information System (INIS)
Zevakov, S.A.; Barkov, L.M.; Arenkhovel', Kh.
2006-01-01
The components T 20 and T 21 of the tensor analysis capability of the elastic electron scattering on deuteron are measured in the momentum transfer range of 8.4-21.6 fm -2 . The form factors of deuteron G C and G Q are defined in the momentum transfer range where the monopole charge form factor G C turns into zero. The preliminary measuring results of T 20 , T 21 and T 22 of the deuteron photodisintegration reaction in the photon energy range of 25-500 MeV and the proton departure angles equal to 20 deg-40 deg and 75 deg-105 deg are presented. The experimental results are compared with the theoretical predictions [ru
EDS'09: 13th International Conference on Elastic & Diffractive Scattering
CERN. Geneva
2009-01-01
The series of International Conferences on Elastic and Diffractive Scattering was founded in 1985 in the picturesque old French town of Blois, famous for its XIV - XVIIth century château, inside of which the first meeting took place. Since then, meetings have been organised every two years in different places of the world: New York (1987), Evanston (1989), Isola d'Elba (1991), Providence (1993), Blois (1995), Seoul (1997), Protvino (1999), Prague (2001), Helsinki (2003), Blois (2005) and Hamburg (2007). The conference will focus on the most recent experimental and theoretical results in particle physics with an emphasis on Quantum Chromodynamics (QCD). http://cern.ch/eds09/ The conference agenda is now full. No further contributions can be accepted.
Proton and neutron densities from elastic electron scattering
International Nuclear Information System (INIS)
Frois, B.
1979-01-01
Elastic electron scattering has now determined extremely fine details of the shape of the nuclear groound state. The combination of (e,e) and muonic X-rays data are giving informations that are among the most precise on nuclear structure. This enables to see all the limitations of existing theories. However, we begin to have a very coherent description of nuclei with the self consistent field theories to a few percent. A very significant progress has been achieved with the calculations of RPA correlations in the round state in a self consistent way. Only recent experiments (on medium and heavy nuclei) of some significance for the understanding of the structure of the nucleus are reviewed
Contribution to the study of the elastic scattering of the system 16O+12C
International Nuclear Information System (INIS)
Charles, Pierre.
1981-03-01
It is generally accepted, in the study of elastic scattering of the 16 O+ 12 C system, that each resonance corresponds to an inherent state of the angular momentum. It does not seem satisfactory to attribute an angular momentum to a resonance without having studied the variation in the angular matrix elements at a scattering resonance in terms of the energy. Now, when not one angular distribution, but a set of angular distributions is examined at adjacent energies, the conclusion is reached that a partial wave has no particular behaviour, but that the structures observed are due to a correlation between the different partial waves. The structures observed between 19 MeV and 24 MeV in the centre of mass system (35 to 40 MeV in 28 Si) do not correspond to inherent states of the angular momentum. Then, one must either assume that the total momentum is not a constant of the movement or that the structures observed correspond to groupings of different levels of angular momentum. The phase shift analysis clearly suggests the existence of groupings of levels reflecting the presence of intermediate structures at 36 MeV and 39 MeV in 28 Si. At such an excitation energy, the mean lives of these structures are assumed to be very short and hence the width of the different levels is great with regard to their spacing: this does not make it possible to show up the 'fine structure' of the resonances because, (a) all the resonant partial waves interfere with each other and (b) the continuous coupling introduces a fluctuating part in the scattering amplitude. The exchange process of two 12 C cores is certainly not unimportant and it has been noticed that certain behaviours of the angular distributions are well reproduced when a term depending on the parity is added to the optical potential [fr
Forward diffraction amplitude of pp and pp elastic scattering at accelerator energies
International Nuclear Information System (INIS)
Kawasaki, M.; Maehara, T.; Yonezawa, M.
2004-01-01
A simple relation between the total cross section and the forward exponential slope of the elastic differential cross section of pp and pp scattering is indicated. An interpretation of this relation is presented as the formation of a black-disk structure for the elastic diffraction interaction of hadron-hadron scattering at the nonasymptotic energy region
Low energy elastic electron scattering from polyatomic targets
International Nuclear Information System (INIS)
Khakoo, M A
2008-01-01
New differential cross-section measurements for elastic electron scattering from ethylene (C 2 H 4 ), three primary alcohols, methanol (CH 3 OH), ethanol (C 2 H 5 OH) and propanol (C 3 H 7 OH) are reported. The measurements are obtained using the relative flow method with a thin aperture as the collimating target gas source. The relative flow method is applied without the molecular diameters restriction imposed by the relative flow pressure condition on helium (the calibrating gas) and the unknown gases (the primary alcohols). The experimental data were taken at incident electron energies of 1eV, 2eV, 5eV, 10eV, 15eV, 20eV, 30eV, 50eV and 100eV, but only a brief survey of these results will be made here. The experimental results are compared to theoretical differential cross-sections are obtained by using the variational multi-channel Schwinger method. Initial comparisons between theory and experiment show that present theory is well-able to model low electron scattering from these polyatomic targets.
Nuclear isospin mixing and elastic parity-violating electron scattering
International Nuclear Information System (INIS)
Moreno, O.; Sarriguren, P.; Moya de Guerra, E.; Udias, J.M.; Donnelly, T.W.; Sick, I.
2009-01-01
The influence of nuclear isospin mixing on parity-violating elastic electron scattering is studied for the even-even, N=Z nuclei 12 C, 24 Mg, 28 Si, and 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.
Study of elastic scattering between heavy ions. Reaction channel influence
International Nuclear Information System (INIS)
Doubre, Hubert.
1978-01-01
The role of absorption on the behavior of heavy ion angular distributions and excitaton functions has been investigated on light and medium mass systems. Comparison between 20 Ne+ 12 C and 16 O+ 16 O systems which lead to the same compound nucleus, shows that it originates from the direct channels strongly coupled to the entrance channel. Structures in the excitation functions occur for almost all the light systems and it is shown that the damping observed for heavier systems such as 40 Ca+ 40 Ca, essentially results on the predominance of Coulomb effects which hide the nuclear structure effects. Thus no valuable information on the details of S-matrix can be extracted for such an heavy system. A coherent description of the elastic scattering, based on a splitting of the scattering amplitude into two components, the modulus of each component varying smoothly as a function of energy and angle. The interference between these sub-amplitudes give rise to interference effects in angular distributions and excitation functions. The study of the main reaction channels of the 40 Ca+ 40 Ca system - i.e. deep inelastic reactions and fusion - also shows that the closed-shell nature of the interacting nuclei does not play any role in these processes due to the excitation processes in the first stage of the reactions which destroy the specific structure of the nuclei [fr
The recoil proton polarization in πp elastic scattering
International Nuclear Information System (INIS)
Seftor, C.J.
1988-09-01
The polarization of the recoil proton for π + p and π - 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 3 East experimental area of the Los Alamos Meson Physics Facility. Beam intensities varied from 0.4 to 1.0 x 10 7 π - 's/sec and from 3.0 to 10.0 x 10 7 π + '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
Near- and subbarrier elastic and quasielastic scattering of the weakly bound 6Li projectile on 144Sm
International Nuclear Information System (INIS)
Monteiro, D. S.; Otomar, D. R.; Lubian, J.; Gomes, P. R. S.; Capurro, O. A.; Marti, G. V.; Arazi, A.; Figueira, J. M.; Heimann, D. Martinez; Negri, A. E.; Pacheco, A. J.; Niello, J. O. Fernandez; Guimaraes, V.
2009-01-01
High-precision data of backward-angle elastic and quasielastic scattering for the weakly bound 6 Li projectile on 144 Sm target at deep-sub-barrier, near-, and above-barrier energies were measured. From the deep-sub-barrier data, the surface diffuseness of the nuclear interacting potential was studied. Barrier distributions were extracted from the first derivatives of the elastic and quasielastic excitation functions. It is shown that sequential breakup through the first resonant state of the 6 Li is an important channel to be included in coupled-channels calculations, even at deep-sub-barrier energies
Improved measurements of elastic properties at acoustic resonant frequencies
International Nuclear Information System (INIS)
Rosinger, H.E.; Ritchie, I.G.; Shillinglaw, A.J.
1976-01-01
The choice of specimens of rectangular cross section for determination of dynamic elastic moduli by the resonant bar technique is often dictated by specimen fabrication problems. The specimen of rectangular cross section lends itself to accurate determination of elastic vibration shapes by a method in which a simple noncontacting optical transducer is used. The unequivocal indexing of the various vibration modes obtained in this way more than compensates for the added computational difficulties associated with rectangular geometry. The approximations used in the calculations of Young's modulus and the shear modulus for bars of rectangular cross section are tested experimentally and it is shown that high precision can be obtained. Determinations of changes in dynamic elastic moduli with temperature or stress are also described. (author)
Results in pion proton scattering near the higher resonances (1961)
International Nuclear Information System (INIS)
Falk-Vairant, P.; Valladas, G.
1961-01-01
We present briefly the available Information on the total cross sections for pion proton scattering in the energy region from 400 MeV to 1.5 GeV. We also have collected all results on total cross sections for particular channels like elastic scattering, inelastic scattering and charge exchange. Using new results on the total cross section for neutral events, we have plotted separately the cross section for elastic and for inelastic scattering in the T = 1/2 state. (authors) [fr
Free-vibration acoustic resonance of a nonlinear elastic bar
Tarumi, Ryuichi; Oshita, Yoshihito
2011-02-01
Free-vibration acoustic resonance of a one-dimensional nonlinear elastic bar was investigated by direct analysis in the calculus of variations. The Lagrangian density of the bar includes a cubic term of the deformation gradient, which is responsible for both geometric and constitutive nonlinearities. By expanding the deformation function into a complex Fourier series, we derived the action integral in an analytic form and evaluated its stationary conditions numerically with the Ritz method for the first three resonant vibration modes. This revealed that the bar shows the following prominent nonlinear features: (i) amplitude dependence of the resonance frequency; (ii) symmetry breaking in the vibration pattern; and (iii) excitation of the high-frequency mode around nodal-like points. Stability of the resonant vibrations was also addressed in terms of a convex condition on the strain energy density.
Acoustic resonances of fluid-immersed elastic cylinders and spheroids: Theory and experiment
Niemiec, Jan; Überall, Herbert; Bao, X. L.
2002-05-01
Frequency resonances in the scattering of acoustic waves from a target object are caused by the phase matching of surface waves repeatedly encircling the object. This is exemplified here by considering elastic finite cylinders and spheroids, and the phase-matching condition provides a means of calculating the complex resonance frequencies of such objects. Tank experiments carried out at Catholic University, or at the University of Le Havre, France by G. Maze and J. Ripoche, have been interpreted using this approach. The experiments employed sound pulses to measure arrival times, which allowed identification of the surface paths taken by the surface waves, thus giving rise to resonances in the scattering amplitude. A calculation of the resonance frequencies using the T-matrix approach showed satisfactory agreement with the experimental resonance frequencies that were either measured directly (as at Le Havre), or that were obtained by the interpretation of measured arrival times (at Catholic University) using calculated surface wave paths, and the extraction of resonance frequencies therefrom, on the basis of the phase-matching condition. Results for hemispherically endcapped, evacuated steel cylinders obtained in a lake experiment carried out by the NSWC were interpreted in the same fashion.
Elastic Nonlinear Response in Granular Media Under Resonance Conditions
Jia, X.; Johnson, P. A.
2004-12-01
We are studying the elastic linear and nonlinear behavior of granular media using dynamic wave methods. In the work presented here, our goal is to quantify the elastic nonlinear response by applying wave resonance. Resonance studies are desirable because they provide the means to easily study amplitude dependencies of elastic nonlinear behavior and thus to characterize the physical nature of the elastic nonlinearity. This work has implications for a variety of topics, in particular, the in situ nonlinear response of surface sediments. For this work we constructed an experimental cell in which high sensitivity dynamic resonance studies were conducted using granular media under controlled effective pressure. We limit our studies here to bulk modes but have the capability to employ shear waves as well. The granular media are composed of glass beads held under pressure by a piston, while applying resonance waves from transducers as both the excitation and the material probe. The container is closed with two fitted pistons and a normal load is applied to the granular sample across the top piston. Force and displacement are measured directly. Resonant frequency sweeps with frequencies corresponding to the fundamental bulk mode are applied to the longitudinal source transducer. The pore pressure in the system is 1 atm. The glass beads used in our experiments are of diameter 0.5 mm, randomly deposited in a duralumin cylinder of diameter 30 mm and height of 15 mm. This corresponds to a granular skeleton acoustic wave velocity of v ª 750m/s under 50 N of force [0.07 Mpa]. The loaded system gives fundamental mode resonances in the audio frequency band at half a wavelength where resonance frequency is effective-pressure dependent. The volume fraction of glass beads thus obtained is found to be 0.63 ± 0.01. Plane-wave generating and detecting transducers of diameter 30 mm are placed on axis at the top and bottom of the cylindrical container in direct contact with the glass
Kundrát, Vojtech; Kaspar, Jan; Procházka, Jirí
2010-01-01
The standard description of common influence of both the Coulomb and hadronic elastic scattering in the proton - proton elastic collisions at high energies with the help of West and Yennie complete amplitude is shown to be theoretically inconsistent. The approach being based on the eikonal model amplitude removes these troubles. The preference of its applica- tion to the analysis of experimental data and in obtaining the predictions of contemporary models for proton - proton high energy elastic hadronic scattering are discussed.
International Nuclear Information System (INIS)
Durand, Gerard.
1974-01-01
First the different theories used for studying pion-nucleus scattering and especially Glauber microscopic model and Kisslinger optical model are summarized. From the comparison of these two theories it was concluded that Kisslinger's was better for studying pion-nucleus scattering near the (3/2-3/2) resonance. The potential was developed, with a local corrective term, proposed by this author. This new term arises from taking into account correctly the Lorentz transformation from the pion-nucleon center of mass to the pion nucleus center of mass system. A coupled-channel formalism was developed allowing the study of pion-nucleus elastic scattering and also the study of single and double charge exchange reactions on nucleus with N>Z. The influence of the new term and the shape of nucleon densities on π- 12 C scattering was studied near 200MeV. It was found that at the nucleus surface the neutron density was larger than the proton density. On the other hand, a maximum of sensibility to the different nuclear parameters was found near 180MeV and for elastic scattering angles greater than 100 deg. The calculations of the total cross section for simple and double charge exchange for 13 C and 63 Cu yielded results simular to those of previous theories and showed the same discrepancy between theory and experiment in the resonance region [fr
Mitri, Farid
2014-11-01
The generalized theory of resonance scattering (GTRS) by an elastic spherical target in acoustics is extended to describe the arbitrary scattering of a finite beam using the addition theorem for the spherical wave functions of the first kind under a translation of the coordinate origin. The advantage of the proposed method over the standard discrete spherical harmonics transform previously used in the GTRS formalism is the computation of the off-axial beam-shape coefficients (BSCs) stemming from a closed-form partial-wave series expansion representing the axial BSCs in spherical coordinates. With this general method, the arbitrary acoustical scattering can be evaluated for any particle shape and size, whether the particle is partially or completely illuminated by the incident beam. Numerical examples for the axial and off-axial resonance scattering from an elastic sphere placed arbitrarily in the field of a finite circular piston transducer with uniform vibration are provided. Moreover, the 3-D resonance directivity patterns illustrate the theory and reveal some properties of the scattering. Numerous applications involving the scattering phenomenon in imaging, particle manipulation, and the characterization of multiphase flows can benefit from the present analysis because all physically realizable beams radiate acoustical waves from finite transducers as opposed to waves of infinite extent.
Elastic and Raman scattering of 8.5-11.4 MeV photons from 159Tb, 165Ho, and 237Np
International Nuclear Information System (INIS)
Bar-Noy, T.; Moreh, R.
1977-01-01
Differential cross sections for elastic and inelastic Raman scattering from the deformed heavy nuclei 159 Tb, 165 Ho and 237 Np were measured at five energies between 8.5 and 11.4 MeV. Angular distributions at four angles between 90 0 and 140 0 for both elastic and inelastic scattering at 9.0 and 11.4 MeV were also measured. The monoenergetic photons were obtained from thermal neutron capture in Ni and Cr. All the angular distributions and the elastic and Raman scattering at the higher energies are in good overall agreement with theoretical predictions. The theory is based on a modified simple rotator model of the giant resonance in which the effect of Delbrueck scattering was included. A trend of both the elastic and Raman scattering at lower energies to be stronger than expected are suggested by the data. However, the ratio between the Raman and elastic scattering seem to be in good agreement with theory throughout the whole energy range. This shows that there is no need to introduce a direct nonresonant component to the imaginary part of the elastic scattering amplitude to explain the experimental data. (Auth.)
Elastic scattering, inelastic scattering, and transfer reactions induced by 12C bombardment of 12C
International Nuclear Information System (INIS)
Stokstad, R.G.; Wieland, R.M.; Fulmer, C.B.; Hensley, D.C.; Raman, S.; Snell, A.H.; Stelson, P.H.
1977-06-01
Graphs and tables of differential cross sections are presented for the elastic scattering of 12 C by 12 C, the single excitation (Q = -4.43 MeV) and the mutual excitation (Q = -8.86 MeV) for 14 bombarding energies in the range 70.7 less than or equal to E/sub lab/ less than or equal to 126.7 MeV. Differential cross sections for one- and two-nucleon transfer are presented for E/sub lab/ = 93.8 MeV
International Nuclear Information System (INIS)
Amos, K.; Allen, L.J.; Steward, C.; Hodgson, P.E.; Sofianos, S.A.
1995-01-01
Direct solution of the Schroedinger equation and inversion methods of analysis of elastic scattering data are considered to evaluate the information that they can provide about the physical interaction between colliding nuclear particles. It was found that both optical model and inversion methods based upon inverse scattering theories are subject to ambiguities. Therefore, it is essential that elastic scattering data analyses are consistent with microscopic calculations of the potential. 25 refs
Energy Technology Data Exchange (ETDEWEB)
Amos, K.; Allen, L.J.; Steward, C. [Melbourne Univ., Parkville, VIC (Australia). School of Physics; Hodgson, P.E. [Oxford Univ. (United Kingdom). Dept. of Physics; Sofianos, S.A. [University of South Africa (UNISA), Pretoria (South Africa). Dept. of Physics
1995-10-01
Direct solution of the Schroedinger equation and inversion methods of analysis of elastic scattering data are considered to evaluate the information that they can provide about the physical interaction between colliding nuclear particles. It was found that both optical model and inversion methods based upon inverse scattering theories are subject to ambiguities. Therefore, it is essential that elastic scattering data analyses are consistent with microscopic calculations of the potential. 25 refs.
Electron scattering by an atom in the field of resonant laser radiation
International Nuclear Information System (INIS)
Agre, M.; Rapoport, L.
1982-01-01
The collision of an electron with an atom in the field of intense electromagnetic radiation that is at resonance with two atomic multiplets is investigated theoretically. Expressions are obtained for the amplitudes of the elastic and inelastic scattering with emission (absorption) of photons. The case of a ground state at resonance with a doublet is considered in detail. It is shown that photon absorption takes place predominantly in the case of resonance in inelastic transitions from a state of the lower multiplet, and photon emission takes place in transitions from a state of the upper multiplet
Report of study meeting on nuclear physics of quasi-elastic scattering
International Nuclear Information System (INIS)
1992-10-01
This meeting was held for three days from June 8 to 10, 1992, as one of the study meetings of Research Center for Nuclear Physics, Osaka University. The lectures were given on spin observables in quasi-elastic scattering, calculation of spin observables in 12 C, 40 Ca(p,n) reaction in quasifree scattering region, present state of quasi-elastic scattering, first results of (p,n) quasifree scattering with the new facility of the RCNP, spin-isospin response function and effect of Δ-hole configuration in finite nuclei, effective polarization of nuclei and observed amount of spin, (p,2p) measurement in the RCNP, quasi-elastic scattering in 2 H, 3 He and 4 He of polarized protons, quasifree Δ formation, 3 He(gamma, pπ ± ) reaction in Δ region, search for isobar components in 3 He by quasifree knockout studies, nonquasi-elastic process in photonuclear reaction, QF and NQF processes in gamma d→π + π - pn, coincidence scattering experiment in quasi-elastic scattering region, exclusive electron scattering of 3 He with full inclusion of final state interaction, quasi-elastic electron scattering and internucleon correlation and 13 other themes. (K.I.)
Sensitivity of the elastic scattering matrix elements to the range of the inelastic potentials
International Nuclear Information System (INIS)
Rawitscher, G.H.; Rasoanaivo, R.Y.
1983-01-01
The solution to a system of coupled equations is examined with regard to the effect of the long range part of the inelastic potentials upon the elastic phase shifts. It is found that those parts of the inelastic potentials which occur beyond the range of the elastic to inelastic transition potentials affect the elastic phase shifts in only a minor way. The proof is given theoretically by means of a Green's function formulation which includes the long range part of the inelastic potentials perturbatively. When applied to the calculation of the effect of breakup on the deuteron-nucleus elastic scattering, the argument confirms the finding that errors in the long range part of the potentials in the breakup channels do not sensitively affect the elastic deuteron scattering cross section. This result explains why the elastic scattering is not very sensitive to the choice of the discretization procedure of the breakup space
Probing the phase of the elastic pp scattering amplitude with vortex proton beams
International Nuclear Information System (INIS)
Ivanov, I. P.
2013-01-01
We show that colliding vortex proton beams instead of (approximate) plane waves can lead to a direct measurement of how the overall phase of the scattering amplitude changes with the scattering angle. In elastic pp scattering, this will open a novel way to measure the parameter ρ(t) and probe the real part of the Pomeron.
Probing the phase of the elastic pp scattering amplitude with vortex proton beams
Energy Technology Data Exchange (ETDEWEB)
Ivanov, I. P. [IFPA, Universite de Liege, Allee du 6 Aout 17, batiment B5a, 4000 Liege, Belgium Sobolev Institute of Mathematics, Koptyug avenue 4, 630090, Novosibirsk (Russian Federation)
2013-04-15
We show that colliding vortex proton beams instead of (approximate) plane waves can lead to a direct measurement of how the overall phase of the scattering amplitude changes with the scattering angle. In elastic pp scattering, this will open a novel way to measure the parameter {rho}(t) and probe the real part of the Pomeron.
Relativistic corrections to the elastic electron scattering from 208Pb
International Nuclear Information System (INIS)
Chandra, H.; Sauer, G.
1976-01-01
In the present work we have calculated the differential cross sections for the elastic electron scattering from 208 Pb using the charge distributions resulting from various corrections. The point proton and neutron mass distributions have been calculated from the spherical wave functions for 208 Pb obtained by Kolb et al. The relativistic correction to the nuclear charge distribution coming from the electromagnetic structure of the nucleon has been accomplished by assuming a linear superposition of Gaussian shapes for the proton and the neutron charge form factor. Results of this calculation are quite similar to an earlier calculation by Bertozzi et al., who have used a different wave function for 208 Pb and have assumed exponential smearing for the proton corresponding to the dipole fit for the form factor. Also in the present work, reason for the small spin orbit contribution to the effective charge distribution is discussed in some detail. It is also shown that the use of a single Gaussian shape for the proton smearing usually underestimates the actual theoretical cross section
pp Elastic Scattering: New Results from EDDA (COSY)
International Nuclear Information System (INIS)
Scobel, W.; EDDA Collaboration
2000-01-01
In the EDDA experiment excitation functions of proton--proton elastic scattering are studied with narrow steps in the projectile momentum range from 0.8 to 3.4 GeV/c and angular range 35 o ≤ Θ cm ≤ 90 o with a detector providing ΔΘ cm ∼ 1.4 o resolution and 85% solid angle coverage. Measurements are performed continuously during projectile acceleration on the Cooler Synchrotron COSY. In phase 1 of the experiment spin-averaged differential cross sections dσ/dOmega have been measured with an internal CH 2 fiber target; background corrections were derived from measurements with a carbon fiber target and from Monte Carlo simulations of inelastic pp contributions. The results provide excitation functions and angular distributions of high precision and internal consistency. In phase 2 of the experiment excitation functions of the analyzing power A N have been measured using a polarized (P≥75%) atomic beam target, and those of the polarization correlation parameters A NN , A SS and A SL will be measured later on with the polarized COSY beam. The measured excitation functions are compared to recent phase shift analyses, and their impact on them is discussed. So far evidence for narrow structures was neither found in the spin-averaged cross sections nor in the analyzing powers
pp Elastic Scattering: New Results from EDDA (COSY)
International Nuclear Information System (INIS)
Scobel, W.; EDDA Collaboration
2000-01-01
In the EDDA experiment excitation functions of proton - proton elastic scattering are studied with narrow steps in the projectile momentum range from 0.8 to 3.4 GeV/c and angular range 35 degree ≤ Θ cm ≤ 90 degree with a detector providing ΔΘ cm ∼ 1.4degree resolution and 85% solid angle coverage. Measurements are performed continuously during projectile acceleration on the Cooler Synchrotron COSY. In phase 1 of the experiment spin-averaged differential cross sections dσ/dΩ have been measured with an internal CH 2 fiber target; background corrections were derived from measurements with a carbon fiber target and from Monte Carlo simulations of inelastic pp contributions. The results provide excitation functions and angular distributions of high precision and internal consistency. In phase 2 of the experiment excitation functions of the analyzing power A N have been measured using a polarized (P≥75%) atomic beam target, and those of the polarization correlation parameters A NN , A SS and A SL will be measured later on with the polarized COSY beam. The measured excitation functions are compared to recent phase shift analyses, and their impact on them is discussed. So far evidence for narrow structures was neither found in the spin-averaged cross sections nor in the analyzing powers
pp Elastic Scattering: New results from EDDA (COSY)
International Nuclear Information System (INIS)
Scobel, W.
2000-01-01
In the EDDA experiment excitation functions of proton-proton elastic scattering are studied with narrow steps in the projectile momentum range from 0.8 to 3.4 GeV/c and the angular range 35 deg. ≤Θ cm ≤90 deg. with a detector providing ΔΘ cm ≅1.4 deg. resolution and 85% solid angle coverage. Measurements are performed continuously during projectile acceleration in the Cooler Synchrotron COSY. In phase 1 of the experiment spin-averaged differential cross sections dσ/dΩ have been measured with an internal CH 2 fiber target; background corrections were derived from measurements with a carbon fiber target and from Monte Carlo simulations of inelastic pp contributions. The results provide excitation functions and angular distributions of high precision and internal consistency. In phase 2 of the experiment excitation functions of the analyzing power A N have been measured using a polarized (P≥75%) atomic beam target, and those of the polarization correlation parameters A NN , A SS and A SL will be measured lateron with the polarized COSY beam. The measured excitation functions are compared to recent phase shift analyses, and their impact on them is discussed. So far evidence for narrow structures was neither found in the spin averaged cross sections nor in the analyzing powers
pp Elastic Scattering: New results from EDDA (COSY)
Scobel, W.
2000-06-01
In the EDDA experiment excitation functions of proton-proton elastic scattering are studied with narrow steps in the projectile momentum range from 0.8 to 3.4 GeV/c and the angular range 35°⩽Θcm⩽90° with a detector providing ΔΘcm≈1.4° resolution and 85% solid angle coverage. Measurements are performed continuously during projectile acceleration in the Cooler Synchrotron COSY. In phase 1 of the experiment spin-averaged differential cross sections dσ/dΩ have been measured with an internal CH2 fiber target; background corrections were derived from measurements with a carbon fiber target and from Monte Carlo simulations of inelastic pp contributions. The results provide excitation functions and angular distributions of high precision and internal consistency. In phase 2 of the experiment excitation functions of the analyzing power AN have been measured using a polarized (P⩾75%) atomic beam target, and those of the polarization correlation parameters ANN, ASS and ASL will be measured lateron with the polarized COSY beam. The measured excitation functions are compared to recent phase shift analyses, and their impact on them is discussed. So far evidence for narrow structures was neither found in the spin averaged cross sections nor in the analyzing powers.
Portable bacterial identification system based on elastic light scatter patterns
Directory of Open Access Journals (Sweden)
Bae Euiwon
2012-08-01
Full Text Available Abstract Background Conventional diagnosis and identification of bacteria requires shipment of samples to a laboratory for genetic and biochemical analysis. This process can take days and imposes significant delay to action in situations where timely intervention can save lives and reduce associated costs. To enable faster response to an outbreak, a low-cost, small-footprint, portable microbial-identification instrument using forward scatterometry has been developed. Results This device, weighing 9 lb and measuring 12 × 6 × 10.5 in., utilizes elastic light scatter (ELS patterns to accurately capture bacterial colony characteristics and delivers the classification results via wireless access. The overall system consists of two CCD cameras, one rotational and one translational stage, and a 635-nm laser diode. Various software algorithms such as Hough transform, 2-D geometric moments, and the traveling salesman problem (TSP have been implemented to provide colony count and circularity, centering process, and minimized travel time among colonies. Conclusions Experiments were conducted with four bacteria genera using pure and mixed plate and as proof of principle a field test was conducted in four different locations where the average classification rate ranged between 95 and 100%.
Exploration of Elastic Scattering Rates for Supersymmetric Dark Matter
Ellis, Jonathan Richard; Olive, Keith A; Ellis, John
2001-01-01
We explore the possible cross sections for the elastic scattering of neutralinos chi on nucleons p,n in the minimal supersymmetric extension of the standard model (MSSM). Universality of the soft supersymmetry-breaking scalar masses for the Higgs multiplets is not assumed, but the MSSM parameters are nevertheless required to lead consistently to an electroweak vacuum. We explore systematically the region of MSSM parameter space where LEP and other accelerator constraints are respected, and the relic neutralino density lies in the range 0.1 < Omega_chi h^2 < 0.3 preferred by cosmology. We also discuss models with Omega_chi h^2 < 0.1, in which case we scale the density of supersymmetric dark matter in our galactic halo by Omega_chi h^2 / 0.1, allowing for the possible existence of some complementary form of cold dark matter. We find values of the cross sections that are considerably lower than the present experimental sensitivities. At low neutralino masses, m_chi < 100 GeV, the cross sections may b...
Influence of argon impurities on the elastic scattering of x-rays from imploding beryllium capsules
Saunders, A. M.; Chapman, D. A.; Kritcher, A. L.; Schoff, M.; Shuldberg, C.; Landen, O. L.; Glenzer, S. H.; Falcone, R. W.; Gericke, D. O.; Döppner, T.
2018-03-01
We investigate the effect of argon impurities on the elastic component of x-ray scattering spectra taken from directly driven beryllium capsule implosions at the OMEGA laser. The plasma conditions were obtained in a previous analysis [18] by fitting the inelastic scattering component. We show that the known argon impurity in the beryllium modifies the elastic scattering due to the larger number of bound electrons. We indeed find significant deviations in the elastic scattering from roughly 1 at.% argon contained in the beryllium. With knowledge of the argon impurity fraction, we use the elastic scattering component to determine the charge state of the compressed beryllium, as the fits are rather insensitive to the argon charge state. Finally, we discuss how doping small fractions of mid- or high-Z elements into low-Z materials could allow ionization balance studies in dense plasmas.
Hof, AL; Boom, H; Robinson, C; Rutten, W; Neuman, M; Wijkstra, H
1997-01-01
With a newly developed Controlled-Release Ergometer the complete characteristic of the series elastic component can be measured in human muscles. Previous estimates were based on the resonance method: muscle elasticity was assessed from the resonance frequency of the muscle elasticity connected to a
Auger vs resonance neutralization in low energy He+ ion scattering
International Nuclear Information System (INIS)
Woodruff, D.P.
1983-01-01
He + ions incident on a metal surface can neutralize either by an Auger or resonant charge exchange. While the Auger process has always been thought to be dominant, recent theoretical interest in the simpler one-electron resonance process has led to suggestions that this alone can account for the neutralization seen in low energy He + ion scattering. In this paper this assertion is analysed by looking at the wider information available on charge exchange processes for He + ion scattering through comparison with Li + ion scattering, the importance of multiple scattering in both these scattering experiments and the results of ion neutralization spectroscopy. These lead to the conclusion that while resonance neutralization to produce metastable He* may well occur at a substantial rate in He + ion scattering, the dominant process leading to loss of ions from the final scattered signal is Auger neutralization as originally proposed. (author)
Observations of resonance-like structures for positron-atom scattering at intermediate energies
International Nuclear Information System (INIS)
Dou, L.
1993-01-01
Absolute values of elastic differential cross sections (DCS's) are measured for position (e + ) scattering by argon (8.7-300 eV) krypton (6.7-400 eV) and also neon (13.6-400 eV) using a crossed-beam experimental setup. When the DCS's are plotted at fixed scattering angles of 30 degrees, 60 degrees, 90 degrees and 120 degrees versus energy it has been found that well-defined resonance-like structures are found at an energy of 55-60 eV for argon and at 25 and 200 eV for krypton, with a broader structure found between 100-200 eV for neon. These observed resonance-like structures are unusual because they occur at energies well above the known inelastic thresholds for these atoms. They may represent examples of open-quotes coupled channel shape resonancesclose quotes, first predicted by Higgins and Burke [1] for e + -H scattering in the vicinity of 36 eV (width ∼ 4 eV), which occurs only when both the elastic and positronium formation scattering channels are considered together. A more recent e + -H calculation by Hewitt et al. [2] supports the Higgins and Burke prediction. These predictions and the present observations suggest the existence of a new type of atomic scattering resonance
Microscopic study of {sup 6}He elastic scattering around the Coulomb barrier
Energy Technology Data Exchange (ETDEWEB)
Descouvemont, P. [Physique Nucléaire Théorique et Physique Mathématique, C.P. 229, Université Libre de Bruxelles (ULB), B 1050 Brussels (Belgium)
2016-07-07
We investigate {sup 6}He scattering on {sup 27}Al, {sup 58}Ni, {sup 120}Sn, and {sup 208}Pb in a microscopic version of the Continuum Discretized Coupled Channel (CDCC) method. We essentially focus on energies around the Coulomb barrier. The {sup 6}He nucleus is described by an antisymmetric 6-nucleon wave function, defined in the Resonating Group Method. The {sup 6}He continuum is simulated by square-integrable positive-energy states. The model does not depend on any adjustable parameter as it is based only on well known nucleon-target potentials. We show that experimental elastic cross sections are fairly well reproduced. The calculation suggests that breakup effects increase for high target masses. For a light system such as {sup 6}He+{sup 27}Al, breakup effects are small, and a single-channel approximation provides fair results.
Effects of Pauli's principle in the. cap alpha. - /sup 16/O elastic scattering
Energy Technology Data Exchange (ETDEWEB)
Schechter, H; Canto, L F; Breitschaft, A M
1986-03-01
'Exact' microscopic methods like the RGM (Resonating Group Method) and the GCM (Generator Coordinate Method) and approximate methods like the OCM (Orthogonality Condition Model) are used to study the effects of Pauli's Principle in the ..cap alpha..-/sup 16/O elastic scattering. A method to derive 'exact' effective potentials for the OCM is introduced. These potentials, derived from RGM wave functions, make the OCM identical to the RGM and they have the advantage of being free from poles associated to the forbidden states. Numerical calculations are made with V2 and B1 nucleon-nucleon forces at energies in the range 0-30 MeV. The potentials and the resulting phase-shifts are compared to those obtained from the approximate method suggested by Friedrich and Canto. The problem of searching for local, state independent, potentials for the OCM is discussed.
Analyzing powers in π+p elastic scattering at intermediate energies
International Nuclear Information System (INIS)
Mokhtari, A.; Briscoe, W.J.; Eichon, A.D.
1985-01-01
The analyzing power, A/sub N/, has been measured for π + p elastic scattering at p/sub π/ = 471, 547, 625, and 687 MeV/c on a transversely polarized target. The results are compared with three recent partial-wave analyses for the isospin (3/2) channel. The agreement with our data for all three analyses is good at 471 MeV/c and reasonable at 547 and 625 MeV/c. At 687 MeV/c two of the analyses show a sharp maximum near costheta = -0.4 which is not seen in the data. There is no indication in our data of the existence of new, narrow Δ resonances
Optical model theory of elastic electron- and positron-atom scattering at intermediate energies
International Nuclear Information System (INIS)
Joachain, C.J.
1977-01-01
It is stated that the basic idea of the optical model theory is to enable analysis of the elastic scattering of a particle from a complex target by replacing the complicated interactions between the beam and the target by an optical potential, or pseudopotential, in which the incident particle moves. Once the optical potential is determined the original many-body elastic scattering problem reduces to a one-body situation. The resulting optical potential is, however, a very complicated operator, and the formal expressions obtained from first principles for the optical potential can only be evaluated approximately in a few simple cases, such as high energy elastic hadron-nucleus scattering, for the the optical potential can be expressed in terms of two-body hadron-nucleon amplitudes, and the non-relativistic elastic scattering of fast charged particles by atoms. The elastic scattering of an electron or positron by a neutral atom at intermediate energies is here considered. Exchange effects between the projectile and the atomic electrons are considered; also absorption and polarisation effects. Applications of the full-wave optical model have so far only been made to the elastic scattering of fast electrons and positrons by atomic H, He, Ne, and Ar. Agreements of the optical model results with absolute measurements of differential cross sections for electron scattering are very good, an agreement that improves as the energy increases, but deteriorates quickly as the incident energy becomes lower than 50 eV for atomic H or 100 eV for He. For more complex atoms the optical model calculations also appear very encouraging. With regard to positron-atom elastic scattering the optical model results for positron-He scattering differ markedly at small angles from the corresponding electron-He values. It would be interesting to have experimental angular distributions of positron-atom elastic scattering in order to check predictions of the optical model theory. (U.K.)
K-p backward elastic scattering between 476 and 1084 MeV/c
International Nuclear Information System (INIS)
Hamilton, R.P.
1979-09-01
The differential cross-section for K - p backward elastic scattering was measured in steps of 10-20 MeV/c between 476 and 1084 MeV/c at the Brookhaven AGS. A negative kaon beam was focused onto a 21 cm long liquid hydrogen target and the forward scattered protons were identified kinematically by means of a single arm magnetic spectrometer. A Monte Carlo computer program aided in the subtraction of background events and in the calculation of correction factors. The new data have an average statistical precision of 2.5% which is an order of magnitude improvement over previous results. Together with a new partial wave analysis, the new data give additional evidence for a resonance between 1700 and 1725 MeV. The best fit to the data finds this to be a D 13 resonance with a mass of 1708 MeV and a width of 27 MeV. Comparable improvement in precision was also obtained in a measurement of the differential cross section for K - p → Σ - π + in which the π + emerges at 0 0 . 47 references
7Li neutron-induced elastic scattering cross section measurement using a slowing-down spectrometer
Directory of Open Access Journals (Sweden)
Heusch M.
2010-10-01
Full Text Available A new integral measurement of the 7Li neutron induced elastic scattering cross section was determined in a wide neutron energy range. The measurement was performed on the LPSC-PEREN experimental facility using a heterogeneous graphite-LiF slowing-down time spectrometer coupled with an intense pulsed neutron generator (GENEPI-2. This method allows the measurement of the integral elastic scattering cross section in a slowing-down neutron spectrum. A Bayesian approach coupled to Monte Carlo calculations was applied to extract naturalC, 19F and 7Li elastic scattering cross sections.
Elastic π-d scattering at momentum of 552 MeV/c
International Nuclear Information System (INIS)
Dakhno, L.G.; Kravtsov, A.V.; Makarov, M.M.; Medvedev, V.I.; Obrant, G.Z.; Poromov, V.I.; Sarantsev, V.V.; Sokolov, G.L.; Sherman, S.G.
1980-01-01
The differential cross-section of the elastic π - d-scattering at the momentum of 552 MeV/c has been measured in the range of angles 20-180 deg in the L.s. by a deuterium 35-cm bubble chamber placed in a 14.8 kgf magnetic field. The total cross section of the elastic scattering is 7.9+-0.7 mbn. The results of calculations of the pion elastic scattering by deuteron performed by the Glauber theory are discussed
Ramírez Suárez, O. L.; Sparenberg, J.-M.
2017-09-01
We introduce a simplified effective-range function for charged nuclei, related to the modified K matrix but differing from it in several respects. Negative-energy zeros of this function correspond to bound states. Positive-energy zeros correspond to resonances and "echo poles" appearing in elastic-scattering phase-shifts, while its poles correspond to multiple-of-π phase shifts. Padé expansions of this function allow one to parametrize phase shifts on large energy ranges and to calculate resonance and bound-state properties in a very simple way, independently of any potential model. The method is first tested on a d -wave 12C+α potential model. It is shown to lead to a correct estimate of the subthreshold-bound-state asymptotic normalization constant (ANC) starting from the elastic-scattering phase shifts only. Next, the 12C+α experimental p -wave and d -wave phase shifts are analyzed. For the d wave, the relatively large error bars on the phase shifts do not allow one to improve the ANC estimate with respect to existing methods. For the p wave, a value agreeing with the 12C(6Li,d )16O transfer-reaction measurement and with the recent remeasurement of the 16Nβ -delayed α decay is obtained, with improved accuracy. However, the method displays two difficulties: the results are sensitive to the Padé-expansion order and the simplest fits correspond to an imaginary ANC, i.e., to a negative-energy "echo pole," the physical meaning of which is still debatable.
Phase variation of nucleon-nucleon amplitude for proton-12C elastic scattering
International Nuclear Information System (INIS)
Deng Yibing; Wang Shilai; Yin Gaofang
2006-01-01
Franco and Yin studied for α- 4 He, 3 He, 2 He, 1 He elastic-scattering by using the phase of the nucleon-nucleon elastic-scattering amplitude varies with momentum transfer in the framework of Glauber multiple scattering theory at intermediate energy. The phase variation leads to large changes in the differential cross sections, and brings the Glauber theory into agreement with experimental data. Later Lombard and Maillet is based on the suggestion by Franco and Yin studied for the p- 4 He elastic-scattering in the framework of Glauber theory, and found this phase to be actually important for the description of spin observables. Recently Wang Shilai and Deng Yibing et al studied for the p- 4 He elastic-scattering in the framework of KMT multiple scattering theory at intermediate energy, and found this phase lead to differential cross sections and polarization, which are in better agreement with experimental data. This paper is based on the suggestion by Franco and Yin that the phase of the nucleon-nucleon scattering amplitude should vary with momentum transfer. The proton elastic scattering on 12 C is studied in the KMT multiple scattering theory with microscopic momentum space first term optical potential. The Coulomb interactions are taken into account in our calculation. The theoretical calculation results show that the phase leads to differential cross section and polarization are in better agreement with experimental data. In conclusion this phase is actually important in the framework of KMT theory. (authors)
Resonant frequency and elastic modulus measurements on hardened cement pastes
International Nuclear Information System (INIS)
Lee, D.J.
1982-12-01
A new technique for measuring resonant frequency and elastic modulus is described. This has been used on specimens of hardened cement paste containing water with no simulated waste, and the results compared with measurements of ultrasonic pulse velocity, dimensional movements and compressive strength made on the same formulations. In addition, measurements were made on a specimen containing simulated waste which demonstrated the applicability of the new technique for following the development of the mechanical properties of cemented simulant radioactive waste in the laboratory. (U.K.)
Resonant scattering of surface plasmon polaritons by dressed quantum dots
Energy Technology Data Exchange (ETDEWEB)
Huang, Danhong; Cardimona, Dave [Air Force Research Laboratory, Space Vehicles Directorate, Kirtland Air Force Base, New Mexico 87117 (United States); Easter, Michelle [Department of Mechanical Engineering, Stevens Institute of Technology, 1 Castle Point Terrace, Hoboken, New Jersey 07030 (United States); Gumbs, Godfrey [Department of Physics and Astronomy, Hunter College of the City University of New York, 695 Park Avenue, New York, New York 10065 (United States); Maradudin, A. A. [Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States); Lin, Shawn-Yu [Department of Electrical, Computer and Systems Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180 (United States); Zhang, Xiang [Department of Mechanical Engineering, 3112 Etcheverry Hall, University of California at Berkeley, Berkeley, California 94720 (United States)
2014-06-23
The resonant scattering of surface plasmon-polariton waves (SPP) by embedded semiconductor quantum dots above the dielectric/metal interface is explored in the strong-coupling regime. In contrast to non-resonant scattering by a localized dielectric surface defect, a strong resonant peak in the spectrum of the scattered field is predicted that is accompanied by two side valleys. The peak height depends nonlinearly on the amplitude of SPP waves, reflecting the feedback dynamics from a photon-dressed electron-hole plasma inside the quantum dots. This unique behavior in the scattered field peak strength is correlated with the occurrence of a resonant dip in the absorption spectrum of SPP waves due to the interband photon-dressing effect. Our result on the scattering of SPP waves may be experimentally observable and applied to spatially selective illumination and imaging of individual molecules.
Nuclear resonant scattering beamline at SPring-8
Energy Technology Data Exchange (ETDEWEB)
Harami, Taikan [Japan Atomic Energy Research Inst., Kamigori, Hyogo (Japan). Kansai Research Establishment
1996-04-01
Mainly by Japan Atomic Energy Research Institute, the Institute of Physical and Chemical Research and Japan Synchrotron Radiation Research Institute, the construction of the Super Photon ring-8 GeV (SPring-8) which is the large scale synchrotron radiation facility for a high luminance light source placing emphasis on short wavelength region (shorter than about 1 nm) is in progress at the Harima Science Park City, Hyogo Prefecture. The features of the SPring-8 are the high luminance of light, the good parallelism and directionality of light, the quasi-monochromatic light with variable wavelength, and the possibility of design from straight polarization to circular polarization. The injection system that accelerates electrons up to 8 GeV and the storage ring storing the 8 GeV electrons for long hours, and 61 beamlines are explained. The manufacture of the nuclear resonant scattering beamline as the beamline for joint utilization was begun. Its transport channel and the experiment hutch are shown. By the features of undulator synchrotron radiation, the research on the matters with small recoilless fraction such as biological substances, liquid, gas and others and the research on time-dependent phenomena become feasible anew. The research on the dynamic structural analysis of heme protein is planned. (K.I.)
Negative pion-nucleus elastic scattering at 20 and 40 MeV
International Nuclear Information System (INIS)
Burleson, G.; Blanpied, G.; Cottingame, W.; Daw, G.; Park, B.; Seth, K.K.; Barlow, D.; Iversen, S.; Kaletka, M.; Nann, H.; Saha, A.; Smith, D.; Redwine, R.P.; Burger, W.; Farkhondeh, M.; Saghai, B.; Anderson, R.
1994-01-01
Differential cross sections for the elastic scattering of 20 and 40 MeV π - by nuclei ranging from 12 C to 208 Pb are reported. Comparisons are made with the predictions of the Michigan State University (MSU) optical potential
Oh, Juwon; Alkhalifah, Tariq Ali
2016-01-01
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
A least squares calculational method: application to e±-H elastic scattering
International Nuclear Information System (INIS)
Das, J.N.; Chakraborty, S.
1989-01-01
The least squares calcualtional method proposed by Das has been applied for the e ± -H elastic scattering problems for intermediate energies. Some important conclusions are made on the basis of the calculation. (author). 7 refs ., 2 tabs
Two-photon exchange corrections in elastic lepton-proton scattering
Energy Technology Data Exchange (ETDEWEB)
Tomalak, Oleksandr; Vanderhaeghen, Marc [Johannes Gutenberg Universitaet Mainz (Germany)
2015-07-01
The measured value of the proton charge radius from the Lamb shift of energy levels in muonic hydrogen is in strong contradiction, by 7-8 standard deviations, with the value obtained from electronic hydrogen spectroscopy and the value extracted from unpolarized electron-proton scattering data. The dominant unaccounted higher order contribution in scattering experiments corresponds to the two photon exchange (TPE) diagram. The elastic contribution to the TPE correction was studied with the fixed momentum transfer dispersion relations and compared to the hadronic model with off-shell photon-nucleon vertices. A dispersion relation formalism with one subtraction was proposed. Theoretical predictions of the TPE elastic contribution to the unpolarized elastic electron-proton scattering and polarization transfer observables in the low momentum transfer region were made. The TPE formalism was generalized to the case of massive leptons and the elastic contribution was evaluated for the kinematics of upcoming muon-proton scattering experiment (MUSE).
Contribution of alpha cluster exchange to elastic and inelastic 16O--20Ne scattering
International Nuclear Information System (INIS)
Stock, R.; Schneider, W.F.W.; Jahnke, U.; Hendrie, D.L.; Mahoney, J.; Maguire, C.F.; Scott, D.K.; Wolschin, G.
1975-01-01
The cluster structure of the ground state rotational band of 20 Ne was studied via the elastic and inelastic scattering of 50 MeV 20 Ne from 16 O. Angular distributions are compared with microscopic calculations
Theoretical predictions for pp and panti p elastic scattering in the TeV energy domain
International Nuclear Information System (INIS)
Bourrely, C.; Martin, A.
1984-01-01
We present theoretical predictions on total cross-sections and elastic scattering in the TeV energy domain obtained from the present experimental situation at the ISR and the panti p Collider. (orig.)
Resonances in the potential scattering and decay of metastable states
International Nuclear Information System (INIS)
Batsch, J.
1975-04-01
The analytic properties of the S-matrix in the complex energy plane are reviewed for potential scattering with particular attention to resonance scattering and decay of metastable states. For a one dimensional model potential with a potential barrier and a repulsive core exact formulas are derived for the energy and width of a resonance in terms of the scattering amplitudes of the barrier and the repulsive core alone. For narrow resonances simple and intuitive results are obtained, which are applied to semiclassical cases where the WKB approximation is valid. (orig.) [de
Resonant inelastic scattering by use of geometrical optics.
Schulte, Jörg; Schweiger, Gustav
2003-02-01
We investigate the inelastic scattering on spherical particles that contain one concentric inclusion in the case of input and output resonances, using a geometrical optics method. The excitation of resonances is included in geometrical optics by use of the concept of tunneled rays. To get a quantitative description of optical tunneling on spherical surfaces, we derive appropriate Fresnel-type reflection and transmission coefficients for the tunneled rays. We calculate the inelastic scattering cross section in the case of input and output resonances and investigate the influence of the distribution of the active material in the particle as well as the influence of the inclusion on inelastic scattering.
Shape dependent resonance light scattering properties of gold nanorods
International Nuclear Information System (INIS)
Zhu Jian; Huang Liqing; Zhao Junwu; Wang Yongchang; Zhao Yanrui; Hao Limei; Lu Yimin
2005-01-01
Suspended gold nanorods with mean aspect ratio 2.5 have been synthesized via electrochemical method. Resonance scattering properties have been studied. Two scattering peaks fixed at 400 and 640 nm are due to the scattering of the gold nanorods via coupling to the transverse and longitudinal surface plasmon resonance. The quasi-static calculation results indicate that with the increasing aspect ratio of the nanorods, the longer wavelength scattering peak red shifts linearly and the shorter wavelength peak blue shifts non-linearly. When aspect ratio a/b = 1.0, ellipse degenerate to sphere and the two peaks unite into one peak at 450 nm
Phase shift analysis of pion-nucleon elastic scattering from the threshold to 2.5 GeV
International Nuclear Information System (INIS)
Ayed, Rachid.
1976-10-01
An energy-independent phase-shift analysis of pion-nucleon elastic scattering is performed from threshold to 2.5 GeV/c 2 masses. It uses a coherent set of data (cross sections and polarizations for the 3 final states: π + p, π - p and π 0 n) constructed from a considerable number (approximately 30000) of experimental points. Empirical criteria of smoothness behavior with energy of the partial waves allowed to obtain a unique solution, i.e. one set of phases shifts (up to I waves) at each energy. The consistency of the solution has been checked by a dispersion relation on the B invariant amplitude. The partial amplitudes obtained have been fitted separately, as a function of energy, in order to extract resonance from background. New resonances of small elasticity have been identified. Parameters (mass, width and elasticity) of all resonant states are given. A dynamical interpretation of the resonance is discussed and their recurrence in the Chew-Frautschi plot are shown [fr
Depolarization in the elastic scattering of 17 MeV polarized protons from 9Be
International Nuclear Information System (INIS)
Baker, M.P.
1975-01-01
The Wolfenstein depolarization parameter D(theta) was measured for the elastic scattering of 17-MeV protons from 9 Be at laboratory scattering angles between 70 0 and 120 0 in 10 0 steps with uncertainties ranging from 0.05 to 0.07. The reaction was initiated by polarized protons and the polarization of those protons elastically scattered by the 9 Be analyzed using a high-resolution, silicon polarimeter. Several of the measured values of D(theta) differed significantly from unity, indicating non-zero probability for proton spin-flip in the elastic scattering process. Theoretical estimates of the depolarization-parameter angular distribution have been made using a multipole expansion of the elastic-scattering amplitude in terms of the amount of angular momentum transferred to the target nucleus during the scattering process. Here the J = 0, 1 and 2 contributions to the scattering amplitude have been explicitly treated for the scattering from 9 Be(I = 3 / 2 ). The J = 0 terms are calculated using the standard, spherical optical-model. The J = 1 and 2 terms can be calculated using DWBA. Both spherical and tensor forms are considered for the J = 1 interaction. The spin-flip probabilities predicted assuming reasonable strengths for the J = 1 potentials are much smaller than those observed experimentally. The J = 2 contribution to the spin-flip probability is calculated assuming a rotational model for 9 Be. Predictions of the J = 2, elastic spin-flip probability are substantially larger than the predictions for the J = 1 contribution and are in rough agreement with the present data. The results of recent coupled-channels calculations also support the conclusion that large elastic spin-flip probabilities can be produced by the J = 2 term in the elastic scattering amplitude
Reaction Mechanism and Structure Interplay for Proton Elastic Scattering from Halo Nuclei
International Nuclear Information System (INIS)
Crespo, R.; Johnson, R.C.
1999-01-01
The aim of this work is to clarify what properties of the projectile w.f. are relevant to describe elastic scattering of halo nuclei from stable nuclei. In particular, we examine how far elastic scattering observables probe correlation effects among projectile nucleons. Our treatment is based on a multiple scattering expansion of the proton-projectile transition amplitude in a form which is well adapted to the weakly bound cluster picture of halo nuclei. In the specific case of 11 Li scattering from protons at 800 MeV/u we show that because core recoil effects are significant, scattering cross sections can not, in general, be deduced from knowledge of the total matter density alone. We advocate that the optical potential concept for the scattering of halo nuclei on protons should be avoided and that the multiple scattering series for the full transition amplitude should be used instead
Reaction mechanism and structure interplay for proton elastic scattering from halo nuclei
International Nuclear Information System (INIS)
Crespo, R.; Johnson, R. C.
1999-01-01
The aim of this work is to clarify what properties of the projectile w.f. are relevant to describe elastic scattering of halo nuclei from stable nuclei. In particular, we examine how far elastic scattering observables probe correlation effects among projectile nucleons. Our treatment is based on a multiple scattering expansion of the proton-projectile transition amplitude in a form which is well adapted to the weakly bound cluster picture of halo nuclei. In the specific case of 11 Li scattering from protons at 800 MeV/u we show that because core recoil effects are significant, scattering crosssections cannot, in general, be deduced from knowledge of the total matter density alone. We advocate that the optical potential concept for the scattering of halo nuclei on protons should be avoided and that the multiple scattering series for the full transition amplitude should be used instead
Theory of atom displacements induced by fast electron elastic scattering in solids
International Nuclear Information System (INIS)
Cruz, C. M.; Pinera, I.; Abreu, Y.; Leyva, A.
2006-01-01
Present contribution deals with the theoretical description of the conditions favoring the occurrence of single fast electron elastic scattering in solids, leading to the displacement of atoms from their crystalline sites. Firstly, the Moliere-Bethe-Goudsmit-Saunderson theory of Multiple Electron Scattering is applied, determining the limiting angle θ l over which the single electron elastic scattering prevails over the multiple one, leading to the evaluation of the total macroscopic cross-section for single electron elastic scattering on the basis of the Mott-Rutherford differential cross-section. On the basis of single electron elastic scattering by atoms in the solid matrix, it was determined the relative number of Atom Displacements produced by the Gamma Radiation as a primary act, as well as the energy and linear momentum of the ejected atoms. The statistical distributions of single electron elastic scattering and of those inducing Atom Displacements at different electron initial energies in comparison with the others electron inelastic scattering channels are discussed, where the statistical sampling methods on the basis of the rejection one where applied simulating different practical situations. (Full text)
ZZ ELAST2, Database of Cross Sections for the Elastic Scattering of Electrons and Positrons by Atoms
International Nuclear Information System (INIS)
2002-01-01
1 - Historical background and information: This database is an extension of the earlier database, 'Elastic Scattering of Electrons and Positrons by Atoms: Database ELAST', Report NISTIR 5188, 1993. Cross sections for the elastic scattering of electrons and positrons by atoms were calculated at energies from 1 KeV to 100 MeV. Up to 10 MeV the RELEL code of Riley was used. Above 10 MeV the ELSCAT code was used, which calculated the factored cross sections and evaluates the screening factor Kscr in WKB approximation. 2 - Application of the data: This database was developed to provide input for the transport codes, such as ETRAN, and includes differential cross sections, the total cross section, and the transport cross sections. In addition, a code TRANSX is provided that generates transport cross section of arbitrary order needed as input for the calculation of Goudsmit-Saunderson multiple-scattering angular distribution 3 - Source and scope of data: The database includes cross sections at 61 energies for electrons and 41 energies from positrons, covering the energy region from 1 KeV to 100 MeV. The number of deflection angles included in the database is 314 angles. Total and transport cross sections are also included in this package. The data files have an extension (jjj) that represents the atomic number of the target atom. The database includes auxiliary data files that enable the ELASTIC code to include the following optional modifications: (i) the inclusion of the exchange correction for electrons scattering; (ii) the conversion of the cross sections for scattering by free atoms to cross sections for scattering by atoms in solids; (iii) ti reduction of the cross sections at large angles and at high energies when the nucleus is treated as an extended rather than a point charge
Directory of Open Access Journals (Sweden)
Pacheco de Carvalho, J. A.
2008-08-01
Full Text Available This article involves computer simulation and surface analysis by nuclear techniques, which are non-destructive. Both the “energy method of analysis” for nuclear reactions and elastic scattering are used. Energy spectra are computer simulated and compared with experimental data, giving target composition and concentration profile information. The method is successfully applied to thick flat targets of graphite, quartz and sapphire and targets containing thin films of aluminium oxide. Depth profiles of ^{12}C and ^{16}O nuclei are determined using (d,p and (d,α deuteron induced reactions. Rutherford and resonance elastic scattering of (^{4}He+ ions are also used.
Este artículo trata de simulación por ordenador y del análisis de superficies mediante técnicas nucleares, que son no destructivas. Se usa el “método de análisis en energia” para reacciones nucleares, así como el de difusión elástica. Se simulan en ordenador espectros en energía que se comparan com datos experimentales, de lo que resulta la obención de información sobre la composición y los perfiles de concentración de la muestra. Este método se aplica con éxito em muestras espesas y planas de grafito, cuarzo y zafiro y muestras conteniendo películas finas de óxido de aluminio. Se calculan perfiles en profundidad de núcleos de ^{12}C y de ^{16}O a través de reacciones (d,p y (d,α inducidas por deuterones. Se utiliza también la difusión elástica de iones (^{4}He+, tanto a Rutherford como resonante.
Theoretical aspects of high energy elastic nucleon scattering
Kundrat, Vojtech; Lokajicek, Milos
2010-01-01
The eikonal model must be denoted as strongly preferable for the analysis of elastic high-energy hadron collisions. The given approach allows to derive corresponding impact parameter profiles that characterize important physical features of nucleon collisions, e.g., the range of different forces. The contemporary phenomenological analysis of experimental data is, however, not able to determine these profiles unambiguously, i.e., it cannot give the answer whether the elastic hadron collisions are more central or more peripheral than the inelastic ones. However, in the collisions of mass objects (like protons) the peripheral behavior of elastic collisions should be preferred.
An application of the Dipole Pomeron model to the pion-proton elastic scattering
International Nuclear Information System (INIS)
Covolan, R.J.M.; Leite, E.E.; Montanha, J.; Soares, M.S.
1994-01-01
The Pomeron model is applied to the pion-proton elastic scattering aiming to describe the total and differential cross sections and the ρ ratio between the scattering amplitude real and imaginary parts. It is also discussed how far the present available experimental results lead to the necessity of adopting a (α 0 > 1) supercritical trajectory. (author). 3 refs., 4 figs
Nuclear and partonic dynamics in high energy elastic nucleus-nucleus scattering
International Nuclear Information System (INIS)
Malecki, A.
1991-01-01
A hybrid description of diffraction which combines a geometrical modelling of multiple scattering with many-channel effects resulting from intrinsic dynamics on nuclear and sub-nuclear level is presented. The application to the 4 He- 4 He elastic scattering is very satisfactory. Our analysis suggests that at large momentum transfers the parton constituents of nucleons immersed in nuclei are deconfined. (author)
Resonant diffuse X-ray scattering from magnetic multilayers
International Nuclear Information System (INIS)
Spezzani, Carlo; Torelli, Piero; Delaunay, Renaud; Hague, C.F.; Petroff, Frederic; Scholl, Andreas; Gullikson, E.M.; Sacchi, Maurizio
2004-01-01
We have measured field-dependent resonant diffuse scattering from a magnetoresistive Co/Cu multilayer. We have observed that the magnetic domain size in zero field depends on the magnetic history of the sample. The results of the X-ray scattering analysis have been compared to PEEM images of the magnetic domains
Discerning the neutron density distribution of 208Pb from nucleon elastic scattering
International Nuclear Information System (INIS)
Karataglidis, S.; Amos, K.; University of Melbourne, VIC; Brown, B.A.; Deb, P.K.
2001-01-01
We seek a measure of the neutron density of 208 Pb from analyses of intermediate energy nucleon elastic scattering. The pertinent model for such analyses is based on coordinate space nonlocal optical potentials obtained from model nuclear ground state densities. As a calibration of the use of Skyrme-Hartree-Fock models the elastic scattering from 40 Cawas considered as well. Those potentials give predictions of integral observables and of angular distributions which show sensitivity to the neutron density. When compared with experiment, and correlated with analyses of electron scattering data, the results suggest that 208 Pb has a neutron skin thickness ∼ 0.17 fm
Measurement of recoil photon polarisation in the electron-proton elastic scattering
International Nuclear Information System (INIS)
Buon, Jean
1965-02-01
This research thesis reports and discusses an experiment which aimed at checking the validity of the Born approximation at the first order in the elastic scattering of high energy electrons on protons. In this experiment, the recoil proton polarisation is measured in an elastic scattering of electrons with energy of 950 MeV and scattering at about 90 degrees in the mass centre system. The author describes the experimental installation, its operation and data collection, reports the analysis of photos and polarisation calculations and errors [fr
Second-class currents and DELTA s in nu(nu-bar)p elastic scattering
Wilkinson, D H
2001-01-01
nu(nu-bar)p elastic scattering is sensitive to the magnitude, DELTA s, of the strange quark's presence within the proton. But it is also sensitive to the strength of second-class currents so we must be assured that the effect of such currents, having regard for the experimental upper limit to their strength, is negligible before extracting DELTA s from such scattering. It is shown that searches for DELTA s through nu(nu-bar)p elastic scattering are unlikely to be troubled by this consideration below neutrino energies of about 0.1 GeV but that at higher energies very serious uncertainty arises.
Li, Ning; Wu, Ya-Jie; Liu, Zhan-Wei
2018-01-01
The relations between the baryon-baryon elastic scattering phase shifts and the two-particle energy spectrum in the elongated box are established. We studied the cases with both the periodic boundary condition and twisted boundary condition in the center of mass frame. The framework is also extended to the system of nonzero total momentum with periodic boundary condition in the moving frame. Moreover, we discussed the sensitivity functions σ (q ) that represent the sensitivity of higher scattering phases. Our analytical results will be helpful to extract the baryon-baryon elastic scattering phase shifts in the continuum from lattice QCD data by using elongated boxes.
Numerical modelling of multiple scattering between two elastical particles
DEFF Research Database (Denmark)
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......Multiple acoustical signal interactions with sediment particles in the vicinity of the seabed may significantly change the course of sediment concentration profiles determined by inversion from acoustical backscattering measurements. The scattering properties of high concentrations of sediments...... is the question of proximity thresholds for influence of multiple scattering in terms of particle properties like volume fraction, average distance between particles or other related parameters. A few available experimental data indicate a significance of multiple scattering in suspensions where the concentration...
Scaling relations in elastic scattering cross sections between multiply charged ions and hydrogen
International Nuclear Information System (INIS)
Rodriguez, V.D.
1991-01-01
Differential elastic scattering cross sections of bare ions from hydrogen are calculated using the eikonal approximation. The results satisfy a scaling relation involving the scattering angle, the ion charge and a factor related to the ion mass. A semiclassical explanation in terms of a distant collision hypothesis for small scattering angle is proposed. A unified picture of related scaling rules found in direct processes is discussed. (author)
Energy Technology Data Exchange (ETDEWEB)
Magazù, S.; Migliardo, F. [Dipartimento di Fisica e di Scienze della Terra dell’, Università degli Studi di Messina, Viale F. S. D’Alcontres 31, 98166 Messina (Italy); Vertessy, B.G. [Institute of Enzymology, Hungarian Academy of Science, Budapest (Hungary); Caccamo, M.T., E-mail: maccamo@unime.it [Dipartimento di Fisica e di Scienze della Terra dell’, Università degli Studi di Messina, Viale F. S. D’Alcontres 31, 98166 Messina (Italy)
2013-10-16
Highlights: • Innovative multiresolution wavelet analysis of elastic incoherent neutron scattering. • Elastic Incoherent Neutron Scattering measurements on homologues disaccharides. • EINS wavevector analysis. • EINS temperature analysis. - Abstract: In the present paper the results of a wavevector and thermal analysis of Elastic Incoherent Neutron Scattering (EINS) data collected on water mixtures of three homologous disaccharides through a wavelet approach are reported. The wavelet analysis allows to compare both the spatial properties of the three systems in the wavevector range of Q = 0.27 Å{sup −1} ÷ 4.27 Å{sup −1}. It emerges that, differently from previous analyses, for trehalose the scalograms are constantly lower and sharper in respect to maltose and sucrose, giving rise to a global spectral density along the wavevector range markedly less extended. As far as the thermal analysis is concerned, the global scattered intensity profiles suggest a higher thermal restrain of trehalose in respect to the other two homologous disaccharides.
Manifestation of 12-quark bag state of 4He nucleus in elastic d4He scattering
International Nuclear Information System (INIS)
Mosallem, A.M.; Uzhinskij, V.V.
2002-01-01
The 4 He d elastic scattering at the momentum of 19.8 GeV/c is analyzed in the framework of the Glauber theory. The scattering amplitude was evaluated using different sets of values of the nucleon-nucleon amplitude parameters and the 4 He density function as a superposition of the Gaussian functions. It is shown that it is impossible to describe simultaneously the p 4 He and d 4 He elastic scattering cross sections using the same set of the NN-amplitude parameters. Inclusion of the twelve-quark bag admixture to the ground state of the 4 He nucleus in the calculations allows one to reproduce the experimental data quite well. It is shown that the admixture manifests itself in the d 4 He elastic scattering in the whole region of the momentum transfer. At small t the effect can be at the level of ∼ 10%. At large t it can be ∼30%
Long Elastic Open Neck Acoustic Resonator for low frequency absorption
Simon, Frank
2018-05-01
Passive acoustic liners, used in aeronautic engine nacelles to reduce radiated fan noise, have a quarter-wavelength behavior, because of perforated sheets backed by honeycombs (with one or two degrees of freedom). However, their acoustic absorption ability is naturally limited to medium and high frequencies because of constraints in thickness. The low ratio "plate thickness/hole diameter" generates impedance levels dependent on the incident sound pressure level and the grazing mean flow (by a mechanism of nonlinear dissipation through vortex shedding), which penalises the optimal design of liners. The aim of this paper is to overcome this problem by a concept called LEONAR ("Long Elastic Open Neck Acoustic Resonator"), in which a perforated plate is coupled with tubes of variable lengths inserted in a limited volume of a back cavity. To do this, experimental and theoretical studies, using different types of liners (material nature, hole diameter, tube length, cavity thickness) are described in this paper. It is shown that the impedance can be precisely determined with an analytical approach based on parallel transfer matrices of tubes coupled to the cavity. Moreover, the introduction of tubes in a cavity of a conventional resonator generates a significant shift in the frequency range of absorption towards lower frequencies or allows a reduction of cavity thickness. The impedance is practically independent of sound pressure level because of a high ratio "tube length/tube hole diameter". Finally, a test led in an aeroacoustic bench suggests that a grazing flow at a bulk Mach number of 0.3 has little impact on the impedance value. These first results allow considering these resonators with linear behavior as an alternative to classical resonators, in particular, as needed for future Ultra High Bypass Ratio engines with shorter and thinner nacelles.
Resonance magnetic x-ray scattering study of erbium
DEFF Research Database (Denmark)
Sanyal, M.K.; Gibbs, D.; Bohr, J.
1994-01-01
The magnetic phases of erbium have been studied by resonance x-ray-scattering techniques. When the incident x-ray energy is tuned near the L(III) absorption edge, large resonant enhancements of the magnetic scattering are observed above 18 K. We have measured the energy and polarization dependence...... of this magnetic scattering and analyzed it using a simple model based on electric dipole and quadrupole transitions among atomic orbitals. The line shapes can be fitted to a magnetic structure combining both c-axis-modulated and basal-plane components. Below 18 K, we have observed unusual behavior of the magnetic...
Modifications of nucleons in nuclei in quasi-elastic electron-nucleus scattering
International Nuclear Information System (INIS)
Mulders, P.J.
1988-01-01
In inelastic electron scattering two scaling regions are observed in which the scattering is dominated by quasi-elastic scattering. For large momentum transfers, √Q 2 > 2 GeV/c, the scattering process is dominated by quasi-elastic scattering off quarks, whereas for √Q 2 ≅ 0.5 GeV/c the dominant contribution is quasi-elastic scattering off nucleons. This corresponds nicely to our first order picture of the nucleus consisting of nucleons, which in turn are composed of quarks. In the nucleon-scaling region, possible modifications of nucleon properties show up through a study of the Q 2 dependence and the relative strength of the transverse and longitudinal cross sections. Results of both inclusive (e,e') and exclusive (e,e'p) experiments in the quasi-elastic scattering region indeed show a behavior that could indicate modifications of intrinsic properties of individual nucleons in the nucleus, although the question remains if one has correctly disentangled the effects of the (long range) interactions between nucleons and those connected to the internal structure of nucleons. Even so, a simple (one-parameter) size rescaling for nucleons appears to be inconsistent with the data and also with some known conventional nuclear physics observables. Therefore the inclusion of two-nucleon correlations appears necessary in order to be able to understand the data. Such correlations can for instance be due to the effect of the Pauli principle on the quark level. (orig.)
Magneto-elastic resonant phenomena at the motion of the domain wall in weak ferromagnets
International Nuclear Information System (INIS)
Kuz'menko, A.P.; Zhukov, E.A.; Dobromyslov, M.B.; Kaminsky, A.V.
2007-01-01
Dynamics of domain walls (DWs) in transparent thin orthoferrite samples with weak ferromagnetic ordering is investigated at sub- and supersonic velocities. A resonant increase of Lamb waves and the formation of magnetoelastic solitons under resonant conditions in both an elastic and between a spin and elastic subsystems were observed
International Nuclear Information System (INIS)
Jablonskiz, A.; Salvatz, F.; Powellz, C.J.
2004-01-01
Inelastic mean free paths (IMFPs) of electrons with energies between 100 eV and 5,000 eV have been frequently obtained from measurements of elastic-backscattering probabilities for different specimen materials. A calculation of these probabilities is also required to determine IMFPs. We report calculations of elastic-backscattering probabilities for gold at energies of 100 eV and 500 eV with differential elastic-scattering cross sections obtained from the Thomas-Fermi-Dirac potential and the more reliable Dirac-Hartree-Fock potential. For two representative experimental configurations, the average deviation between IMFPs obtained with cross sections from the two potentials was 11.4 %. (author)
Kang, K.; Fried, H. M.; Tan, C.-I.
1994-02-01
The Table of Contents for the book is as follows: * Preface * `Overview' on Elastic Scattering and Total Cross-Sections * A Precise Measurement of the Real Part of the Elastic Scattering Amplitude at the {S bar{p}pS} * Luminosity Dependent Measurement of the p bar{p} Total Cross Section at √{s} = 541 GeV * Status of Fermilab E-710 * Luminosity-Independent Measurement of bar{p}p Elastic Scattering, Single Diffraction, Dissociation and Total Cross Section at √{s} = 546 and 1800 GeV * Phase Relations Revisited: A Challenge for SSC and LHC * Status of Near-Forward Elastic Scattering * bar{p}p Collisions at √{s} = 1.8 TeV: p, σt and B * p bar{p} Forward Scattering Parameters Results from Fermilab E760 * Photoproduction Results from H1 at HERA * Total and Jet Photoproduction Cross Sections at HERA and Fermilab * Minijet Model for High Energy γp Cross Sections * The Pomeron as Massive Gluons * Large N Theories with Glueball-like Spectra * Unitarity Relations for Gluonic Pomeron * The Donnachie-Landshoff Pomeron vs. QCD * The Odderon Intercept in Perturbative QCD * Theoret. and Phenomenol. Aspects of the Odderon * First Theorist's Gaze at HERA Data at Low xB * H1 Results for Structure Functions at Small x * Partial Photoproduction Cross Sections at √{s} ≈prox 180 GeV and First Results on F2 of the Proton from the ZEUS Experiment * Observation of a New Class of Events in Deep Inelastic Scattering * Jet Production in Muon-Proton and Muon-Nuclei Scattering at Fermilab-E665 * D0 Studies of Perturbative QCD * Large Rapidity Gaps and Single Diffraction Dissociation in High Energy pp and bar{p}p Collisions * Hadron and Reggeon Structure in High Energy Collisions * Monte Carlo Studies of Diffractive Processes in Deep Inelastic Scattering * Elastic Parton-Parton Amplitudes in Geometrical Models * Non-Perturbative QCD Calculations of High-Energy Observables * Effective Field Theory for Diffractive QCD Processes * High Energy Behavior of σtot, ρ, and B - Asymptotic
Dominance of strong absorption in 9Be + 28Si elastic scattering
International Nuclear Information System (INIS)
Zisman, M.S.; Cramer, J.G.; DeVries, R.M.; Goldberg, D.A.; Watson, J.W.
1979-07-01
Because the character of the scattering changes markedly from 6 Li to 12 C projectiles, a study of the 9 Be + 28 Si system was undertaken to examine the transition region. Data were measured at 121.0 and 201.6 MeV. Low-energy data of other investigators were used to carry out global optical model searches. It was found that the elastic scattering of 9 Be from 28 Si is dominated at all energies by relatively strong absorption. This removes much of the sensitivity to the real potential, and even elastic scattering data spanning a range of energies from 13 to 201 MeV do not allow a unique determination of the potential parameters. There is at least circumstantial evidence that 6 Li scattering at low energies (and by implication also 9 Be scattering) may be strongly influenced by breakup processes, although it is not clear that the mechanism is the same. 3 figures, 1 table
International Nuclear Information System (INIS)
Sinha, T.; Kanungo, R.; Samanta, C.; Ghosh, S.; Basu, P.; Rebel, H.
1996-01-01
Alpha- particle scattering from the resonant (3 + 1 ) and non-resonant continuum states of 6 Li is studied at incident energy 10 MeV/A. The α+d breakup continuum part within the excitation energy E ex = 1.475-2.475 MeV is discretized in two energy bins. Unlike the results at higher incident energies, here the coupled-channel calculations show significant breakup continuum coupling effects on the elastic and inelastic scattering. It is shown that even when the continuum-continuum coupling effects are strong, the experimental data of the ground state and the resonant as well as discretized non-resonant continuum states impose stringent constraint on the coupling strengths of the non-resonant continuum states. (orig.). With 2 figs., 1 tab
International Nuclear Information System (INIS)
Breton, Vincent
1990-01-01
We have studied Coulomb effects in the electron-nucleus interaction by measuring electron and positron elastic scattering. The Coulomb field of the nucleus acts differently on theses particles because of their opposite charges. The experiment took place at the Accelerateur Lineaire de Saclay, with 450 MeV electrons and positrons. We measured the emittance of the positron and electron beams. We compared electron and positron beams having the same energy, the same emittance and the same intensity. This way, we measured positron scattering cross sections with 2 % systematic error. By comparing positron and electron elastic scattering cross sections for momentum transfers between 1 and 2 fm -1 , on a Lead 208 target, we showed that the calculations of Coulomb effects in elastic scattering are in perfect agreement with experimental results. The comparison of positron and electron elastic scattering cross sections on Carbon showed that dispersive effects are smaller than 2 % outside the diffraction minima. These two results demonstrate in a definitive way that electron scattering allows to measure charge densities in the center of nuclei with an accuracy of the order of 1 %. (author) [fr
About statistical process contribution to elastic diffraction scattering
International Nuclear Information System (INIS)
Ismanov, E.I.; Dzhuraev, Sh. Kh.; Paluanov, B.K.
1999-01-01
The experimental data on angular distribution show two basic properties. The first one is the presence of back and front peaks. The second one is the angular isotropic distribution near 90 degree, and has a big energy dependence. Different models for partial amplitudes a dl of the diffraction statistical scattering, particularly the model with Gaussian and exponential density distribution, were considered. The experimental data on pp-scattering were analyzed using the examined models
International Nuclear Information System (INIS)
Wu Jiuhui; Zhang Siwen; Zhou Kejiang
2012-01-01
A physical mechanism of phononic band gap and resonant nanoacoustic scattering in an aggregate of two elastic nanospheres is presented in this paper. By considering the Van der Waals (VdW) force between two nanospheres illuminated by nanoacoustic wave, phononic band gap and frequency shift at the lower frequency side, and largely enhanced nanoacoustic scattering at the other frequency range have been found through calculating the form function of the acoustic scattering from the nanosystem. This VdW-force-induced band gap is different from the known mechanisms of Bragg scattering and local resonances for periodic media. It is shown that when the separation distance between two nanospheres is decreasing from 20 to 1 nm, due to the increasing VdW force, the nanoacoustic scattering is much heightened by two order of magnitude, and meanwhile the frequency shift and phononic band gap at the low frequencies are both widened. These results could provide potential applications of nanoacoustic devices.
Time-dependent scattering in resonance lines
International Nuclear Information System (INIS)
Kunasz, P.B.
1983-01-01
A numerical finite-difference method is presented for the problem of time-dependent line transfer in a finite slab in which material density is sufficiently low that the time of flight between scatterings greatly exceeds the relaxation time of the upper state of the scattering transition. The medium is assumed to scatter photons isotropically, with complete frequency redistribution. Numerical solutions are presented for a homogeneous, time-independent slab illuminated by an externally imposed radiation field which enters the slab at t = 0. Graphical results illustrate relaxation to steady state of trapped internal radiation, emergent energy, and emergent profiles. A review of the literature is also given in which the time-dependent line transfer problem is discussed in the context of recent analytical work
Radius anomaly in the diffraction model for heavy-ion elastic scattering
Pandey, L. N.; Mukherjee, S. N.
1984-04-01
The elastic scattering of heavy ions, 20Ne on 208Pb, 20Ne on 235U, 84Kr on 208Pb, and 84Kr on 232Th, is examined within the framework of Frahn's diffraction model. An analysis of the experiment using the "quarter point recipe" of the expected Fresnel cross sections yields a larger radius for 208Pb than the radii for 235U and 232Th. It is shown that inclusion of the nuclear deformation in the model removes the above anomaly in the radii, and the assumption of smooth cutoff of the angular momentum simultaneously leads to a better fit to elastic scattering data, compared to those obtained by the earlier workers on the assumption of sharp cutoff. [NUCLEAR REACTIONS Elastic scattering, 20Ne+208Pb (161.2 MeV), 20Ne+235U (175 MeV), 84Kr+208Pb (500 MeV), 84Kr+232Th (500 MeV), diffraction model, nuclear deformation.
Elastic scattering of 90 - 120 MeV 3He particles and unique optical potential
International Nuclear Information System (INIS)
Hyakutake, M.; Matoba, M.; Kumabe, I.; Fukada, M.; Komatuzaki, T.
1978-01-01
The elastic scattering of 109.2 MeV 3 He particles by 40 Ca, 58 Ni, 90 Zr and 116 Sn has been investigated over a wide angular range. The elastic scattering cross sections have been analyzed in terms of the optical model. The data for each nucleus studied were sufficient to eliminate the discrete ambiguity in the strength of the optical potential; the unique potential which fits the data has real well depth of about 100 MeV and a corresponding volume integral per nucleon pair of about 310 MeV fm 3 . The elastic scattering of 3 He particles by 58 Ni has been further measured at bombarding energies of 89.3 and 118.5 MeV, and the incident-energy dependence of the optical potential of 3 He particles for 58 Ni was obtained. (author)
Bhatia, A. K.; Temkin, A.; Fisher, Richard R. (Technical Monitor)
2001-01-01
We report on the first part of a study of electron-hydrogen scattering, using a method which allows for the ab initio calculation of total and elastic cross sections at higher energies. In its general form the method uses complex 'radial' correlation functions, in a (Kohn) T-matrix formalism. The titled method, abbreviated Complex Correlation Kohn T (CCKT) method, is reviewed, in the context of electron-hydrogen scattering, including the derivation of the equation for the (complex) scattering function, and the extraction of the scattering information from the latter. The calculation reported here is restricted to S-waves in the elastic region, where the correlation functions can be taken, without loss of generality, to be real. Phase shifts are calculated using Hylleraas-type correlation functions with up to 95 terms. Results are rigorous lower bounds; they are in general agreement with those of Schwartz, but they are more accurate and outside his error bounds at a couple of energies,
A comparison of pp and pp elastic scattering at 90 degrees
Eisenhandler, E F; Astbury, A; Gibson, W R; Harrison, M; Hojvat, C; Jones, D P; Kalmus, Peter I P; Kemp, M A R; Lee Chi Kwong, L; Parsons, A S L; Pritchard, T W; Range, W H; Rush, A D; Usher, E C; Williams, D T; Woulds, J N
1974-01-01
A study of low momentum antiproton-proton interactions in the momentum range 0.7 to 2.4 GeV/c has yielded differential cross sections for the elastic channel. An observation of one property of the data when compared with pp elastic scattering within the framework of quark- parton models is presented. The pp and pp systems, related by crossing symmetry, provided significant constraints on any particular model. (13 refs).
A dynamic elastic and inelastic scattering theory of high-energy electrons
International Nuclear Information System (INIS)
Wang Zhonglin
1990-01-01
A review is given on the applications of elastic multislice theory for simulating the images and diffractions of reflection electron microscopy. The limitation of this theory is illustrated according to some experimental observations. A generalized elastic and inelastic multislice theory is then introduced from quantum mechanics; its applications for approaching inelastic plasmon excitation and phonon excitation (or thermal diffuse scattering) are discussed. The energy-filtered inelastic high resolution images can be simulated based on this theory
High-Energy antipp and pp Elastic Scattering and Nucleon Structure
International Nuclear Information System (INIS)
Islam, M.M.; Innocente, V.; Fearnley, T.; Sanguinetti, G.
1987-01-01
High-energy antipp and pp elastic data from the CERN Collider and the ISR are analyzed in the nucleon valence core model. Diffraction is described by a profile function that incorporates crossing symmetry and saturation of Froissart-Martin bound. The model is found to provide a very satisfactory description of the elastic scattering over the whole range of energy and momentum transfer. Implications of the analysis on QCD models of nucleon structure are pointed out
High-Energy antipp and pp Elastic Scattering and Nucleon Structure
Energy Technology Data Exchange (ETDEWEB)
Islam, M.M.; Innocente, V.; Fearnley, T.; Sanguinetti, G.
1987-07-15
High-energy antipp and pp elastic data from the CERN Collider and the ISR are analyzed in the nucleon valence core model. Diffraction is described by a profile function that incorporates crossing symmetry and saturation of Froissart-Martin bound. The model is found to provide a very satisfactory description of the elastic scattering over the whole range of energy and momentum transfer. Implications of the analysis on QCD models of nucleon structure are pointed out.
Quarkonia propagation in QGP: study of elastic and inelastic scattering processes
International Nuclear Information System (INIS)
Berrehrah, H; Aichelin, J; Gossiaux, P B
2011-01-01
We propose to study the quarkonia (φ) propagation in the QGP. We are especially interested in the elastic and inelastic scattering process of these quarkonia in the medium. We developed the Bethe-Salpeter formalism to calculate the elastic cross section (σ elas ) for φ - gluon/hadron. Results obtained in this work show that σ elas (φ - gluon/hadron) might have non negligible effects in the study of Q Q-bar propagation.
Evolution of elastic x-ray scattering in laser-shocked warm dense lithium.
Kugland, N L; Gregori, G; Bandyopadhyay, S; Brenner, C M; Brown, C R D; Constantin, C; Glenzer, S H; Khattak, F Y; Kritcher, A L; Niemann, C; Otten, A; Pasley, J; Pelka, A; Roth, M; Spindloe, C; Riley, D
2009-12-01
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 degrees using a highly oriented pyrolytic graphite 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 Z[over ] and by extension to the choice of ionization model in the radiation-hydrodynamics simulations used to predict plasma properties within the shocked Li.
Evolution of elastic x-ray scattering in laser-shocked warm dense lithium
International Nuclear Information System (INIS)
Kugland, N. L.; Niemann, C.; Gregori, G.; Bandyopadhyay, S.; Spindloe, C.; Brenner, C. M.; Brown, C. R. D.; Constantin, C.; Glenzer, S. H.; Khattak, F. Y.; Kritcher, A. L.; Otten, A.; Pelka, A.; Roth, M.; Pasley, J.; Riley, D.
2009-01-01
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-α photons for x-ray scattering, and the spectrum of scattered photons was recorded at a scattering angle of 120 deg. using a highly oriented pyrolytic graphite 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 Z and by extension to the choice of ionization model in the radiation-hydrodynamics simulations used to predict plasma properties within the shocked Li.
Study of the electrons elastic scattering by atoms through pseudopotentials
International Nuclear Information System (INIS)
Bettega, M.H.F.
1990-01-01
Pseudopotentials allow an extraordinary simplification in the calculation of the electronic structure of atoms, molecules and crystals. Though they have been used extensively for electronic structure calculations, little is known of their applicability to scattering. A study of the pseudopotentials of Bachelet, Hamann and Schuter in the electron scattering by atoms was made, calculating phase-shifts and cross sections for angular momenta 1=0,1 and 2 and energy up to 5 R y. The results for the pseudopotential were compared all-electron calculations. The agreement is very good in a broad energy band. A simplification of the calculation of scattering by complex molecules where an all-electron calculation is impossible is aimed. (author)
The analysis of the elastic scattering of 11Be and 6Li by adiabatic approximation
International Nuclear Information System (INIS)
Takagi, S.
2000-01-01
The unstable nuclei, particularly, the neutron halo nuclei which exist near by the neutron dripline, are recently one of the interesting topics in the nuclear physics. By the adiabatic approximation, R. C. Jhonson et al. have reproduced the experimental differential cross-section of the elastic scattering of the neutron halo nucleus 11 Be (+ l2 C) [1]. We have applied their method to the elastic scattering of another nucleus 6 Li which is not a halo nucleus but has the cluster structure as 11 Be. But it couldn't reproduce the experimental data, so that the method of Johnson et al. is poor in the case of 6 Li. (author)
Sub-barrier fusion and near-barrier quasi-elastic scattering
International Nuclear Information System (INIS)
Kolata, J.J.; Tighe, R.J.
1990-01-01
Elastic scattering of 32 S on 58,64 Ni and fusion of 32 S+ 58,64 Ni and 34 S+ 64 Ni have been measured at energies near the Coulomb barrier. Our results differ in several important respects from previous measurements on these systems. Coupled-channels calculations which explicitly allow for inelastic excitation and single-nucleon transfer reproduce the main features of the new data. Near-barrier elastic scattering of 48 Ca on 40 Ca has also been measured. These data provide evidence for the effect of strong coupling to positive Q-value channels other than single-nucleon transfer. 18 refs., 3 figs
Influence of the halo upon angular distributions for elastic scattering and breakup
International Nuclear Information System (INIS)
Capel, P.; Hussein, M.S.; Baye, D.
2010-01-01
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 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.
Elastic scattering and total reaction cross section for the 6He + 27Al system
International Nuclear Information System (INIS)
Benjamim, E.A.; Lepine-Szily, A.; Mendes Junior, D.R.; Lichtenthaeler, R.; Guimaraes, V.; Gomes, P.R.S.; Chamon, L.C.; Hussein, M.S.; Moro, A.M.; Arazi, A.; Padron, I.; Alcantara Nunez, J.; Assuncao, M.; Barioni, A.; Camargo, O.; Denke, R.Z.; Faria, P.N. de; Pires, K.C.C.
2007-01-01
The elastic scattering of the radioactive halo nucleus 6 He on 27 Al target was measured at four energies close to the Coulomb barrier using the RIBRAS (Radioactive Ion Beams in Brazil) facility. The Sao Paulo Potential (SPP) was used and its diffuseness and imaginary strength were adjusted to fit the elastic scattering angular distributions. Reaction cross-sections were extracted from the optical model fits. The reduced reaction cross-sections of 6 He on 27 Al are similar to those for stable, weakly bound projectiles as 6,7 Li, 9 Be and larger than stable, tightly bound projectile as 16 O on 27 Al
The prediction of Neutron Elastic Scattering from Tritium for E(n) = 6-14 MeV
International Nuclear Information System (INIS)
Anderson, J.D.; Dietrich, F.S.; Luu, T.; McNabb, D.P.; Navratil, P.; Quaglioni, S.
2010-01-01
In a recent report Navratil et al. evaluated the angle-integrated cross section and the angular distribution for 14-MeV n+T elastic scattering by inferring these cross sections from accurately measured p+3He angular distributions. This evaluation used a combination of two theoretical treatments, based on the no-core shell model and resonating-group method (NCSM/RGM) and on the R-matrix formalism, to connect the two charge-symmetric reactions n+T and p+ 3 He. In this report we extend this treatment to cover the neutron incident energy range 6-14 MeV. To do this, we evaluate angle-dependent correction factors for the NCSM/RGM calculations so that they agree with the p+ 3 He data near 6 MeV, and using the results found earlier near 14 MeV we interpolate these correction factors to obtain correction factors throughout the 6-14 MeV energy range. The agreement between the corrected NCSM/RGM and R-Matrix values for the integral elastic cross sections is excellent (±1%), and these are in very good agreement with total cross section experiments. This result can be attributed to the nearly constant correction factors at forward angles, and to the evidently satisfactory physics content of the two calculations. The difference in angular shape, obtained by comparing values of the scattering probability distribution P(μ) vs. μ(the cosine of the c.m. scattering angle), is about ±4% and appears to be related to differences in the two theoretical calculations. Averaging the calculations yields P(μ) values with errors of ±2 1/2 % or less. These averaged values, along with the corresponding quantities for the differential cross sections, will form the basis of a new evaluation of n+T elastic scattering. Computer files of the results discussed in this report will be supplied upon request.
The prediction of Neutron Elastic Scattering from Tritium for E(n) = 6-14 MeV
Energy Technology Data Exchange (ETDEWEB)
Anderson, J D; Dietrich, F S; Luu, T; McNabb, D P; Navratil, P; Quaglioni, S
2010-06-14
In a recent report Navratil et al. evaluated the angle-integrated cross section and the angular distribution for 14-MeV n+T elastic scattering by inferring these cross sections from accurately measured p+3He angular distributions. This evaluation used a combination of two theoretical treatments, based on the no-core shell model and resonating-group method (NCSM/RGM) and on the R-matrix formalism, to connect the two charge-symmetric reactions n+T and p+{sup 3}He. In this report we extend this treatment to cover the neutron incident energy range 6-14 MeV. To do this, we evaluate angle-dependent correction factors for the NCSM/RGM calculations so that they agree with the p+{sup 3}He data near 6 MeV, and using the results found earlier near 14 MeV we interpolate these correction factors to obtain correction factors throughout the 6-14 MeV energy range. The agreement between the corrected NCSM/RGM and R-Matrix values for the integral elastic cross sections is excellent ({+-}1%), and these are in very good agreement with total cross section experiments. This result can be attributed to the nearly constant correction factors at forward angles, and to the evidently satisfactory physics content of the two calculations. The difference in angular shape, obtained by comparing values of the scattering probability distribution P({mu}) vs. {mu}(the cosine of the c.m. scattering angle), is about {+-}4% and appears to be related to differences in the two theoretical calculations. Averaging the calculations yields P({mu}) values with errors of {+-}2 1/2 % or less. These averaged values, along with the corresponding quantities for the differential cross sections, will form the basis of a new evaluation of n+T elastic scattering. Computer files of the results discussed in this report will be supplied upon request.
Energy Technology Data Exchange (ETDEWEB)
Bigio, I.J.; Boyer, J.; Johnson, T.M.; Lacey, J.; Mourant, J.R. [Los Alamos National Lab., NM (United States); Conn, R. [Lovelace Medical Center, Albuquerque, NM (United States); Bohorfoush, A. [Wisconsin Medical School, Milwaukee, WI (United States)
1994-10-01
The Los Alamos National Laboratory has continued the development of the Optical Biopsy System (OBS) for noninvasive, real-time in situ diagnosis of tissue pathologies. Our clinical studies have expanded since the last Biomedical Optics Europe conference (Budapest, September 1993), and we report here on the latest results of clinical tests in gastrointestinal tract. The OBS invokes a unique approach to optical diagnosis of tissue pathologies based on the elastic scattering properties, over a wide range of wavelengths, of the tissue. The use of elastic scattering as the key to optical tissue diagnostics in the OBS is based on the fact that many tissue pathologies, including a majority of cancer forms, manifest significant architectural changes at the cellular and sub-cellular level. Since the cellular components that cause elastic scattering have dimensions typically on the order of visible to near-IR wavelengths, the elastic (Mie) scattering properties will be wavelength dependent. Thus, morphology and size changes can be expected to cause significant changes in an optical signature that is derived from the wavelength-dependence of elastic scattering. The OBS employs a small fiberoptic probe that is amenable to use with any endoscope or catheter, or to direct surface examination. The probe is designed to be used in optical contact with the tissue under examination and has separate illuminating and collecting fibers. Thus, the light that is collected and transmitted to the analyzing spectrometer must first scatter through a small volume of the tissue before entering the collection fiber(s). Consequently, the system is also sensitive to the optical absorption spectrum of the tissue, over an effective operating range of <300 to 950 nm, and such absorption adds valuable complexity to the scattering spectral signature.
Magnetoconductivity of quantum wires with elastic and inelastic scattering
DEFF Research Database (Denmark)
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 ...
Energy-loss of He ions in carbon allotropes studied by elastic resonance in backscattering spectra
Energy Technology Data Exchange (ETDEWEB)
Tosaki, Mitsuo, E-mail: tosaki.mitsuo.3v@kyoto-u.ac.jp [Radioisotope Research Center, Kyoto University, Kyoto 606-8501 (Japan); Rauhala, Eero [Department of Physics, University of Helsinki (Finland)
2015-10-01
Backscattering spectra for {sup 4}He ions incident on carbon allotropes have been measured in the energy range from 4.30 to 4.95 MeV in steps of 50–100 keV at scattering angles of 106° and 170°. We used three carbon allotropes: graphite, diamond and amorphous carbon. For all these allotropes, we can observe the sharp ({sup 4}He, {sup 12}C) elastic nuclear resonance at the He ion energy of 4.265 MeV in the backscattering spectra. By varying the incident He energy, we have systematically analyzed the profiles of the resonance peaks to study the energy-loss processes: stopping cross-sections and energy-loss straggling around the interesting region of the stopping maximum at about 500 keV. We focus on the resonance profiles and investigate an allotropic effect concerning the energy-loss. Furthermore, an energy bunching effect on the straggling is presented and the mechanism is discussed.
Air and ground resonance of helicopters with elastically tailored composite rotor blades
Smith, Edward C.; Chopra, Inderjit
1993-01-01
The aeromechanical stability, including air resonance in hover, air resonance in forward flight, and ground resonance, of a helicopter with elastically tailored composite rotor blades is investigated. Five soft-inplane hingeless rotor configurations, featuring elastic pitch-lag, pitch-flap and extension-torsion couplings, are analyzed. Elastic couplings introduced through tailored composite blade spars can have a powerful effect on both air and ground resonance behavior. Elastic pitch-flap couplings (positive and negative) strongly affect body, rotor and dynamic inflow modes. Air resonance stability is diminished by elastic pitch-flap couplings in hover and forwrad flight. Negative pitch-lag elastic coupling has a stabilizing effect on the regressive lag mode in hover and forward flight. The negative pitch-lag coupling has a detrimental effect on ground resonance stability. Extension-torsion elastic coupling (blade pitch decreases due to tension) decreases regressive lag mode stability in both airborne and ground contact conditions. Increasing thrust levels has a beneficial influence on ground resonance stability for rotors with pitch-flap and extension-torsion coupling and is only marginally effective in improving stability of rotors with pitch-lag coupling.
Unified quantum theory of elastic and inelastic atomic scattering from a physisorbed monolayer solid
DEFF Research Database (Denmark)
Bruch, L. W.; Hansen, Flemming Yssing; Dammann, Bernd
2017-01-01
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...... of specific one-phonon events includes contributions from diffuse inelastic scattering in other phonon modes. Effects of thermally excited phonons are included using a mean field approximation. The theory is applied to an incommensurate Xe/Pt(111) monolayer (incident energy Ei = 4-16 meV), a commensurate Xe...
Resonance electronic Raman scattering in rare earth crystals
International Nuclear Information System (INIS)
Williams, G.M.
1988-01-01
The intensities of Raman scattering transitions between electronic energy levels of trivalent rare earth ions doped into transparent crystals were measured and compared to theory. A particle emphasis was placed on the examination of the effect of intermediate state resonances on the Raman scattering intensities. Two specific systems were studied: Ce 3+ (4f 1 ) in single crystals of LuPO 4 and Er 3+ (4f 11 ) in single crystals of ErPO 4 . 134 refs., 92 figs., 33 tabs
Isomer beam elastic scattering: 26mAl(p, p) for astrophysics
Kahl, D.; Shimizu, H.; Yamaguchi, H.; Abe, K.; Beliuskina, O.; Cha, S. M.; Chae, K. Y.; Chen, A. A.; Ge, Z.; Hayakawa, S.; Imai, N.; Iwasa, N.; Kim, A.; Kim, D. H.; Kim, M. J.; Kubono, S.; Kwag, M. S.; Liang, J.; Moon, J. Y.; Nishimura, S.; Oka, S.; Park, S. Y.; Psaltis, A.; Teranishi, T.; Ueno, Y.; Yang, L.
2018-01-01
The advent of radioactive ground-state beams some three decades ago ultimately sparked a revolution in our understanding of nuclear physics. However, studies with radioactive isomer beams are sparse and have often required sophisticated apparatuses coupled with the technologies of ground-state beams due to typical mass differences on the order of hundreds of keV and vastly different lifetimes for isomers. We present an application of a isomeric beam of 26mAl to one of the most famous observables in nuclear astrophysics: galactic 26Al. The characteristic decay of 26Al in the Galaxy was the first such specific radioactivity to be observed originating from outside the Earth some four decades ago. We present a newly-developed, novel technique to probe the structure of low-spin states in 27Si. Using the Center for Nuclear Study low-energy radioisotope beam separator (CRIB), we report on the measurement of 26mAl proton resonant elastic scattering conducted with a thick target in inverse kinematics. The preliminary results of this on-going study are presented.
Stimulated resonant scattering at stressed fused silica surface
International Nuclear Information System (INIS)
Bouchut, Philippe; Reymermier, Maryse
2015-01-01
The radiative emission in CO 2 laser heated stressed fused silica is radically modified when gold microspheres are on the surface. At high heating rates, the emission dynamics changes from thermoluminescence to stimulated resonant scattering with an emission rate that is increased tenfold and the near infrared (NIR) spectrum is red-shifted. We show that the dynamic tensile stress that rises in heated silica is coupled with a fluctuating electromagnetic field that enables electromagnetic friction between moving OH emitters from silica bulk and NIR resonant scatterers at the silica surface. (paper)
Fusion, resonances and scattering in C reaction
Indian Academy of Sciences (India)
respectively. In each of these regions, we find some important features in the results ofσfus. ... draws attention in the astrophysical studies [2,7]. Here, Ecm and η .... We outline the concept of selective resonance tunneling for fusion in Ü3. In Ü4 ...
Breakup threshold anomaly in the elastic scattering of 6Li on 27Al
International Nuclear Information System (INIS)
Figueira, J. M.; Niello, J. O. Fernandez; Abriola, D.; Arazi, A.; Capurro, O. A.; Barbara, E. de; Marti, G. V.; Heimann, D. Martinez; Negri, A. E.; Pacheco, A. J.; Padron, I.; Gomes, P. R. S.; Lubian, J.; Correa, T.; Paes, B.
2007-01-01
Elastic scattering of the weakly bound 6 Li on 27 Al was measured at near-barrier energies. The data analysis was performed using a Woods-Saxon shape optical potential and also using the double-folding Sao Paulo potential. The results show the presence of the breakup threshold anomaly (BTA), an anomalous behavior when compared with the scattering of tightly bound nuclei. This behavior is attributed to a repulsive polarization potential produced by the coupling to the continuum breakup states
Hadron-proton elastic scattering at 50, 100, and 200 GeV/c momentum
International Nuclear Information System (INIS)
Akerlof, C.W.; Kotthaus, R.; Loveless, R.L.; Meyer, D.I.; Ambats, I.; Meyer, W.T.; Ward, C.E.W.; Eartly, D.P.; Lundy, R.A.; Pruss, S.M.; Yovanovitch, D.D.; Rust, D.R.
1976-01-01
Elastic scattering of hadrons on protons has been measured at momenta of 50, 100, and 200 GeV/c. The meson-proton scattering is found to be independent of momentum and meson type for -t > 0.8 (GeV/c) 2 . The momentum dependence of the pp dip at -t = 1.4 (GeV/c) 2 was investigated. Slope parameters are given
Analysis of the angular distributions of elastically scattered neutrons for 235U
International Nuclear Information System (INIS)
Sukhovitskij, E.Sh.; Benderskij, A.R.; Konshin, V.A.
1976-01-01
Experimental data on the angular distributions of 0.5-15 MeV neutrons elastically scattered by 235 U nuclei are analysed on the basis of Bessel functions and Legendre polynomial expansions. The advantages of the method are that there are no negative cross-sections and relatively few expansion coefficients and that experimental data on scattering at 0 0 and 180 0 are not needed. (author)
Elastic scattering of a Bose-Einstein condensate at a potential landscape
International Nuclear Information System (INIS)
Březinová, Iva; Burgdörfer, Joachim; Lode, Axel U J; Streltsov, Alexej I; Cederbaum, Lorenz S; Alon, Ofir E; Collins, Lee A; Schneider, Barry I
2014-01-01
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
The dispersion relation for the forward elastic electron-atom scattering amplitude
International Nuclear Information System (INIS)
Amusia, M.Y.
1978-01-01
The analytical properties of forward elastic electron-atom scattering amplitude are discussed. It is noted that the occurrence of exchange between the incoming and atomic electrons leads to the appearance of a number of singularities on the negative real axis in the complex energy plane. The conclusion is drawn that the dispersion relation for the forward electron-atom scattering amplitude should also include an integration over the negative energy from - I to - infinity, where I is the ionization potential. (author)
Elastic neutron diffuse scattering in Zr(Ca, Y)O2-x
International Nuclear Information System (INIS)
Barberis, P.; Beuneu, B.; Novion, C.H. de.
1990-01-01
Elastic neutron diffuse scattering has been measured in cubic Zr(Ca, Y)O 2-x at room temperature. The very high diffuse scattering (up to 70 Laue) is explained mostly by the oxygen displacements along directions, and by Ca displacements along . The weak short-range order contribution strongly suggests that oxygen vacancies tend to place as second rather than at first neighbours of a Ca stabilizing ion
Polarization measurements in p-p elastic scattering between 398 and 572 MeV
International Nuclear Information System (INIS)
Aebischer, D.; Favier, B.; Greeniaus, L.G.; Hess, R.; Junod, A.; Lechanoine, C.; Nikles, J.C.; Rapin, D.; Werren, D.W.
1977-01-01
Measurements of the analyzing power for p-p elastic scattering at 398, 455, 497, 530, and 572 MeV are reported. A system of multiwire proportional chambers placed directly in a polarized beam was used to observe the angular region 1.5 0 0 . An increase in P(theta) is observed as a function of both scattering angle and incident kinetic energy. Electromagnetic-nuclear interference is used to obtain direct information in the nuclear interaction. (Auth.)
Elastic scattering of protons on 8Li nucleus in inverse kinematics
International Nuclear Information System (INIS)
Zhusupov, M.A.; Ibraeva, E.T.; Sanfirova, A.B.; Imambekov, O.
2002-01-01
In the present paper the proton elastic scattering on 8 Li in inverse kinematics is studies. The inverse kinematics means that a beam of radioactive nuclei is scattered on a stable hydrogen target. Proton as a target has an advantage during the interaction since it is stable and mechanism of proton-nucleus scattering is quite simple. 8 Li nucleus is considered in the three-body αtn-model with realistic potential of inter-cluster interactions. The wave function of this nucleus is calculated in the work where it was shown that such model well describes the main spectroscopic characteristics of the nucleus, root-mean square radius, binding energy, location of low laying energy levels, magnetic momentum and also total cross section and 7 Li(n, γ) 8 Li reaction rate at a wide energy region. Within Glauber-Sitenko multiply scattering theory, the differential cross section of elastic p 8 Li-scattering has been calculated. The first and the second multiplicities of scattering on nucleons and clusters of the nucleus were taken into account in Ω multiply scattering operator. There were considered several cases when as the initial parameters both amplitudes of nucleon-nucleon and nucleon-cluster scattering were taken. Sensitivity of the differential cross section both to the different wave functions of the target-nucleus and to the parameters of the elementary amplitudes and sensitivity to the scattering multiplicities at several beam energies has been investigated. Comparison with differential cross sections of elastic p 6 Li- and p 7 Li scattering has been carried out
Measurement of Z dependence of elastic scattering cross-sections of 0. 145 MeV gamma rays
Energy Technology Data Exchange (ETDEWEB)
Ghumman, B S [Punjabi Univ., Patiala (India). Dept. of Physics
1981-11-01
The Z dependence of elastic scattering cross-sections of 0.145 MeV gamma rays is investigated at large scattering angles. Measurements are made with scatterers of Pb, W, Sn, Ag, Mo, Zn, Cu, Fe and Al at scattering angles from 75 deg to 150 deg. The experimental results are compared with the available theoretical and experimental data.
Scattering phases for meson and baryon resonances on general moving-frame lattices
Energy Technology Data Exchange (ETDEWEB)
Goeckeler, M. [Regensburg Univ. (Germany). Institut fuer Theoretische Physik; Horsley, R. [Edinburgh Univ. (United Kingdom). School of Physics and Astronomy; Lage, M.; Rusetsky, A. [Bonn Univ. (Germany). Helmholtz-Inst. fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics; Meissner, U.G. [Bonn Univ. (Germany). Helmholtz-Inst. fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics; Forschungszentrum Juelich GmbH (Germany). Inst. fuer Kernphysik; Forschungszentrum Juelich (Germany). Juelich Center for Hadron Physics and JARA - High Performance Computing; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Division; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Zanotti, J.M. [Adelaide Univ., SA (Australia). CSSM, School of Chemistry and Physics
2012-06-15
A proposal by Luescher enables one to compute the scattering phases of elastic two-body systems from the energy levels of the lattice Hamiltonian in a finite volume. In this work we generalize the formalism to S-, P- and D-wave meson and baryon resonances, and general total momenta. Employing nonvanishing momenta has several advantages, among them making a wider range of energy levels accessible on a single lattice volume and shifting the level crossing to smaller values of m{sub {pi}}L.
Elastic scattering of polarized protons on helium three at 800 MeV
International Nuclear Information System (INIS)
Azizi, A.
1985-07-01
A set of spin dependent parameters and cross sections has been measured for polarized p- 3 He elastic scattering over the range of q .7 to 4.2 fm -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 3 He is one of the simplest nuclei, polarized p- 3 He scattering provides a very sensitive test of multiple scattering theories. The theoretical analysis was done by using two different wave functions for 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 and charge-exchange scattering of pions from 3He and 3H
International Nuclear Information System (INIS)
Gibson, B.F.; Hess, A.T.
1976-04-01
We have examined (1) the elastic scattering of pions from the isodoublet 3 He and 3 H and (2) the single charge-exchange reaction 3 H(π + ,π 0 ) 3 He using a formalism which incorporates the π-N multiple scattering to all orders. Emphasis is placed on numerical results which illustrate those features of the differential cross sections that are expected to be of interest to the experimentalist. Realistic nuclear densities corresponding to the form factors of elastic electron scattering were used. Charge-exchange cross sections are presented in terms of angular distributions for both the π 0 and the recoil nucleus. In elastic scattering, Coulomb-nuclear interference effects are significant at incident pion kinetic energies of less than 100 MeV; form factor effects are apparent at large momentum transfer. Comparison of data and theory for π + - 3 He with that for π - - 3 He (or the conjugate π + - 3 H) will provide a test of the convergence of the fixed scatterer, multiple-scattering formalism utilized in this report. 21 figures
Fitting phase shifts to electron-ion elastic scattering measurements
International Nuclear Information System (INIS)
Per, M.C.; Dickinson, A.S.
2000-01-01
We have derived non-Coulomb phase shifts from measured differential cross sections for electron scattering by the ions Na + , Cs + , N 3+ , Ar 8+ and Xe 6+ at energies below the inelastic threshold. Values of the scaled squared deviation between the observed and fitted differential cross sections, χ 2 , for the best-fit phase shifts were typically in the range 3-6 per degree of freedom. Generally good agreement with experiment is obtained, except for wide-angle scattering by Ar 8+ and Xe 6+ . Current measurements do not define phase shifts to better than approx. 0.1 rad even in the most favourable circumstances and uncertainties can be much larger. (author)
A theory of low energy π-3He elastic scattering
International Nuclear Information System (INIS)
Geffen, F.M.M. van.
1991-01-01
The main aim of this work is the construction of a first-order optical potential for the scattering of pions by 3 He at low energy with as few approximations as possible. In particular the Fermi motion is treated extremely carefully by using microscopic 3 He wave functions and by performing the complete Fermi-integral. Differential cross-sections and analyzing powers have been calculated. In a detailed comparison between the first-order optical with one which results from using the semi-factored approximation, it became clear that the latter has the following shortcomings: 1. the dependence of the subenergy on the pion-nucleus scattering angle, and 2. the independence of this energy on the relative motion of the spectator nucleons. (author). 101 refs.; 15 figs.; 3 tabs
Study of the {sup 6}He+{sup 9}Be elastic scattering at low energies
Energy Technology Data Exchange (ETDEWEB)
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
Numerical determination of elastic positron- and electron-atom scattering phaseshifts
International Nuclear Information System (INIS)
Page, B.A.P.
1976-01-01
Numerical investigations of both the positron- and electron-hydrogen systems in the elastic scattering energy region are presented. For the positron-hydrogen system, modifications of the Kohn variational method are used in which the quantities etasub(v) and etasub(Q) are related to the trial wavefunction PSIsub(t) through integral expressions using approximations to the target wavefunction psi. The quantities etasub(v) and etasub(Q) become the Kohn elastic phaseshifts when the exact target wavefunction is used. From the results obtained for the positron-hydrogen system it is conjectured that if the values of either etasub(v) or etasub(Q) display a local maximum when all the nonlinear parameters of PSIsub(t) are varied, then this local maximum value is a good approximation to the Kohn elastic phaseshifts that would be obtained by replacing the approximate psi with the exact psi in the particular PSIsub(t) used in the calculations. Application of this procedure to the positron-helium elastic scattering system is given using Hylleraas-type approximations to the helium ground-state wavefunction. Both the positron- and electron-hydrogen systems are analysed in the elastic scattering energy region using a modified optical potential method. The results suggest that the local maximum value of the modified optical potential phaseshift when all the nonlinear parameters of PSIsub(t) are varied, is reasonably close to the normal optical potential phaseshift obtained when the exact psi is used. (author)
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
Energy Technology Data Exchange (ETDEWEB)
Anderson, E. K.; Boadle, R. A.; Machacek, J. R.; Makochekanwa, C.; Sullivan, J. P. [ARC Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra 0200 (Australia); Chiari, L. [ARC Centre for Antimatter-Matter Studies, Flinders University, GPO Box 2100, Adelaide, 5001 SA (Australia); Buckman, S. J., E-mail: Stephen.buckman@anu.edu.au [ARC Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra 0200 (Australia); Institute of Mathematical Sciences, University of Malaya, Kuala Lumpur (Malaysia); Brunger, M. J. [ARC Centre for Antimatter-Matter Studies, Flinders University, GPO Box 2100, Adelaide, 5001 SA (Australia); Institute of Mathematical Sciences, University of Malaya, Kuala Lumpur (Malaysia); Garcia, G. [Instituto de Fısica Fundamental, Consejo Superior de Investigationes Cientıficas (CSIC), Serrano 113-bis, E-28006 Madrid (Spain); Blanco, F. [Departamento de Fısica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, E-28040 Madrid (Spain); Ingolfsson, O. [Department of Chemistry, Science Institute, University of Iceland, Reykjavík 107 (Iceland)
2014-07-21
Measurements of the grand total and total positronium formation cross sections for positron scattering from uracil have been performed for energies between 1 and 180 eV, using a trap-based beam apparatus. Angular, quasi-elastic differential cross section measurements at 1, 3, 5, 10, and 20 eV are also presented and discussed. These measurements are compared to existing experimental results and theoretical calculations, including our own calculations using a variant of the independent atom approach.
Dispersion relation for elastic electron-hydrogen atom forward scattering amplitude
International Nuclear Information System (INIS)
Kuchiev, M.Yu.; Amusia, M.Ya.
1978-01-01
The elastic e+H forward scattering amplitude is an analytical function in the complex energy E plane and has two cuts on the real axis: 0 < E < infinity and -infinity < E < -B, B being the hydrogen ionization potential. The e+H dispersion relation contains two integrals over the right and left cuts. (Auth.)
Elastic neutrino-electron scattering: a progress report on Exp734 at Brookhaven
International Nuclear Information System (INIS)
Abe, K.; Ahrens, L.A.; Amako, K.
1983-01-01
I will report preliminary results on elastic neutrino-electron scattering from data taken with the 200 ton segmented liquid scintillator - proportional drift-tube neutrino detector at Brookhaven. Features of the detector (such as the active target and long radiation length) permit a uniquely clean signal. Prospects of results from the completed analysis and further data taking are discussed
Neutron-proton elastic scattering between 200 and 500 MeV
International Nuclear Information System (INIS)
Clough, A.S.; Gibson, D.R.; Axen, D.
1979-01-01
Measurements over an extensive angular range of the Dsub(t) and P parameters in free neutron-proton elastic scattering at laboratory energies of 220, 325, 425 and 495 MeV are reported. Experimental and analytical details are given. (author)
Negative pion-nucleus elastic scattering at 30 and 50 MeV
International Nuclear Information System (INIS)
Seth, K.K.; Barlow, D.; Iversen, S.; Kaletka, M.; Nann, H.; Smith, D.; Artuso, M.; Burleson, G.; Blanpied, G.; Daw, G.; Burger, W.J.; Redwine, R.P.; Saghai, B.; Anderson, R.
1990-01-01
Differential cross sections for the elastic scattering of 30 and 50 MeV π - by nuclei ranging from 12 C to 208 Pb have been measured using a range spectrometer. Comparison is made with the predictions of a recent optical-model calculation and the general nature of discrepancies is discussed
Energy dependence of the analyzing power Ayo in the anti p p elastic scattering
International Nuclear Information System (INIS)
Bertini, R.
1991-01-01
The analysing power data A yo of the anti p p elastic scattering at six beam momenta from P lab = 439 MeV/c up to 988 MeV/c are plotted as a function of In(-t). The regularities shown by the data are discussed
Deep-elastic pp scattering at LHCf rom low-x gluons
Czech Academy of Sciences Publication Activity Database
Islam, M.M.; Kašpar, Jan; Luddy, R.J.
2009-01-01
Roč. 24, č. 7 (2009), s. 485-496 ISSN 0217-7323 R&D Projects: GA MŠk LA08015 Institutional research plan: CEZ:AV0Z10100502 Keywords : elastic pp scattering * LHC Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 1.075, year: 2009
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.
Note on the elastic-scattering of few-MeV neutrons from elemental calcium
International Nuclear Information System (INIS)
Smith, A.B.; Guenther, P.T.
1982-03-01
Neutron differential-elastic-scattering cross sections of elemental calcium are measured from 0 . Incident-neutron energy resolutions are approximately 50 to 100 keV. The experimental results are compared with values given in ENDF/B-V and are examined in the context of shielding applications. An optical potential is deduced from the measured values and its possible implications are discussed
(p,4He) elastic scattering at 350, 650, 1050, and 1150 MeV
International Nuclear Information System (INIS)
Aslanides, E.; Brochard, F.; Gorodetzky, P.; Hibou, F.; Lambert, E.
1977-01-01
Angular distributions of p- 4 He elastic scattering differential cross sections have been measured at 350, 650, 1050 and 1150 MeV, in regions of four-momentum transfer squared t=0.02-0.71 (GeV/c) 2 . These new measurements confirm the absence of a pronounced first diffraction minimum. New theoretical analyses are also presented. (Auth.)
How to distinguish elastically scattered light from Stokes shifted light for solid-state lighting?
Meretska, Maryna; Lagendijk, Aart; Thyrrestrup Nielsen, Henri; Mosk, Allard; IJzerman, W.L.; Vos, Willem L.
2016-01-01
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 YAG:Ce+3phosphor particles that both elastically scatter and Stokes shift light in the visible wavelength range (400–700 nm). We
International Nuclear Information System (INIS)
Engel, Y.M.; Friedman, E.; Levine, R.D.
1982-01-01
Radial moments of the real part of the optical potential for elastic scattering of 104 MeV α particles are used as constraints, in determining the nuclear density of maximal entropy. The potential is related to the density by the folding model. (orig.)
Studying the proton 'radius' puzzle with μp elastic scattering
International Nuclear Information System (INIS)
Gilman, R.
2013-01-01
The disagreement between the proton radius determined from muonic hydrogen and from electronic measurements is called the proton radius puzzle. The resolution of the puzzle remains unclear and appears to require new experimental results. An experiment to measure muon-proton elastic scattering is presented here
Investigation of second-order optical potential for elastic π4He scattering
International Nuclear Information System (INIS)
Mach, R.; Sapozhnikov, M.G.
1982-01-01
The calculations of elastic π - 4 He scattering within the framework of the optical model with a second-order potential were performed. The effects of recoil correlations, charge exchange and double spin (isospin) flip in the inter-- mediate states are studied. The correction of the impulse approximation is investigated. Comparison between Kerman-McManus-Thaler and Watson formalisms is made
Intermediate-energy proton- 4He elastic scattering with a microscopic optical potential
International Nuclear Information System (INIS)
Alexander, Y.; Landau, R.H.
1979-01-01
A microscopic, momentum space, optical potential calculation of elastic p- 4 He scattering is compared with 100-200 MeV data over the full angular range. The least sophisticated potential explains the occurrence and energy dependence of the back angle peak. (Auth.)
On the proton exchange contribution to electron-hydrogen atom elastic scattering
International Nuclear Information System (INIS)
Mignaco, J.A.; Tort, A.C.
1979-05-01
It is shown that the exchange contribution to the electron-proton potential Born term in elastic electron-hydrogen atom scattering arises as the non relativistic limit from the exchange of a proton between the two participant electrons - calculated from quantum electrodynamics including properly bound states (as solution of Bethe - Salpeter equation). (Author) [pt
Polarisation analysis of elastic neutron scattering using a filter spectrometer on a pulsed source
International Nuclear Information System (INIS)
Mayers, J.; Williams, W.G.
1981-05-01
The experimental and theoretical aspects of the polarisation analysis technique in elastic neutron scattering are described. An outline design is presented for a filter polarisation analysis spectrometer on the Rutherford Laboratory Spallation Neutron Source and estimates made of its expected count rates and resolution. (author)
Nuclear re-interaction effects in quasi-elastic neutrino nucleus scattering
Energy Technology Data Exchange (ETDEWEB)
Co, G.; Bleve, C.; De Mitri, I.; Martello, D
2002-11-01
The quasi-elastic {nu}-nucleus cross section has been calculated by using a Fermi gas model corrected to consider the re-scattering between the emitted nucleon and the rest nucleus. As an example of the relevance of this effect we show results for the muon production cross section on {sup 16}O target.
Antiproton-proton elastic scattering at 1.8 TeV
International Nuclear Information System (INIS)
Fazal-e-Aleem; Saleem, M.; Yodh, G.B.
1990-01-01
The predictions, based on the generalized Chou-Yang model, are made for the most recent measurements of antiproton-proton elastic scattering at √s = 1.8 TeV. These results have been compared with the recent theoretical predictions of various models. (author)
Antiproton-proton elastic scattering at 1. 8 TeV
Energy Technology Data Exchange (ETDEWEB)
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).
Elastic scattering study of three 4n nuclei systems above the Coulomb barrier
International Nuclear Information System (INIS)
Ashok Kumar; Sarita Kumar; Sunita Kumar
2000-01-01
A comprehensive study of elastic scattering of 4n nuclei, namely 16 O + 40 Ca, 24 Mg + 24 Mg and 32 S + 28 Si is carried out at various incident energies near and above the Coulomb barrier using a semi microscopic approach. In the present work real part of the nucleus-nucleus interaction is microscopically calculated using equivalence relation between RGM and GCM
On the theory of elastic scattering of spin polarized electrons from ferromagnets
International Nuclear Information System (INIS)
Helman, J.S.
1984-01-01
The first Born approximation supposedly inadequate for dealing with elastic scattering of spin polarized electrons on ferromagnets is reconsidered. It is found that when used in conjunction with a spin dependent pseudopotential, it can describe the gross features of the ansisotropy. (Author) [pt
On the theory of elastic scattering of spin polarized electrons from ferromagnets
International Nuclear Information System (INIS)
Helman, J.S.; Baltenspenger, W.
1984-01-01
The first Born approximation supposedly inadequate for dealing with the elastic scattering of spin polarized electrons on ferromagnets is reconsidered. It is found that when used in conjunction with a spin dependent pseudo-potential, it can describe the gross features of the anisotropy. (author) [pt
A closed analytic form for p-d elastic scattering at high energy
International Nuclear Information System (INIS)
Li, Y.; Lo, S.
1983-01-01
Using a simple harmonic oscillator wave function for deuteron it is possible to give an analytic solution in closed form for p-d elastic scattering. It has the advantage of displaying clearly all the contributions separately (D-wave, spin flip etc.). It can also fit experimental data
Limit on flavor-changing neutral currents from a measurement of neutrino-electron elastic scattering
International Nuclear Information System (INIS)
Krakauer, D.A.; Talaga, R.L.; Allen, R.C.; Chen, H.H.; Hausammann, R.; Lee, W.P.; Lu, X.; Mahler, H.J.; Wang, K.C.; Bowles, T.J.; Burman, R.L.; Carlini, R.D.; Cochran, D.R.F.; Doe, P.J.; Frank, J.S.; Potter, M.E.; Sandberg, V.D.; Piasetzky, E.
1992-01-01
From a measurement of the absolute cross section in ν ee - elastic scattering we have set a limit on flavor-changing neutral currents in the neutrino sector. We find that an off-diagonal, flavor-changing coupling is limited to 1-f ee <0.35 (90% C.L.)
Time collimation for elastic neutron scattering instrument at a pulsed source
International Nuclear Information System (INIS)
Aksenov, V.L.; Nikitenko, Yu.V.
1996-01-01
Conditions for carrying out elastic neutron scattering experiments using the time-of-flight technique are considered. It is shown that the employment of time dependent neutron beam collimation in the source-sample flight path increases the luminosity of the spectrometer under certain resolution restrictions. 3 refs., 8 figs
Elastic proton scattering on tritium below the n-3He threshold
Directory of Open Access Journals (Sweden)
Lazauskas R.
2010-04-01
Full Text Available Microscopic calculations using Faddeev-Yakubovski equations in conﬁguration space are performed for low energy elastic proton scattering on 3H nucleus. Realistic nuclear Hamiltonians are used. Coulomb repulsion between the protons as well as isospin breaking eﬀects are rigorously treated.
The neutron-deuteron elastic scattering angular distribution at 95 MeV
Energy Technology Data Exchange (ETDEWEB)
Mermod, Philippe
2004-04-01
The neutron-deuteron elastic scattering differential cross section has been measured at 95 MeV incident neutron energy, with the Medley setup at TSL in Uppsala. The neutron-proton differential cross section has also been measured for normalization purposes. The data are compared with theoretical calculations to investigate the role of three-nucleon force effects.
Low energy 16O+208Pb elastic scattering: an attempt to analyze the microscopic effective potential
International Nuclear Information System (INIS)
Mau, N.V.; Ferrero, J.L.; Pacheco, J.C.; Bilwes, B.
1991-03-01
Elastic scattering of 16 O on 208 Pb is studied at 96, 104, 129.5, 192, 216.6 and 312.6 MeV. The 16 O+ 208 Pb potential is calculated first in the closure approximation model and compared to semi-phenomenological potentials. Then detailed contributions to the polarization real potential and to the imaginary potential due to the coupling of the elastic channels to the inelastic channels are calculated. The results are compared to the authors' model potential and used to test the main assumptions of the model. From that comparison a qualitative interpretation of the success of the model is proposed. At last the elastic scattering cross sections are calculated and compared to the data. (author) 41 refs., 6 figs., 5 tabs
Quantum mechanical study of elastic scattering and rotational excitation of CO by electrons
Onda, K.; Truhlar, D. G.
1980-01-01
Coupling calculations of differential, integral, and momentum transfer cross sections for pure elastic scattering and rotational excitation of CO by electron impact are reported. The calculations are based on a static charge distribution that has correct dipole and quadrupole moments, has cusps at the nuclei, and is augmented by an SCF treatment of charge polarization and a local approximation for exchange. The rotationally summed cross sections, with no adjustable parameters in the scattering calculation, are in reasonably good agreement with the experimental cross sections but are somewhat larger at small scattering angles.
11. international conference on elastic and diffractive scattering: towards high energy frontiers
Energy Technology Data Exchange (ETDEWEB)
NONE
2005-07-01
This conference is held every 2 years. Every time these conferences on elastic and diffractive scattering adapt their content to the most recent experimental and theoretical results concerning not only quantum chromodynamics (QCD) but also other fields of particle physics where diffractive physics is present. This year, besides classical themes such as: -) forward scattering, -) total cross-sections, -) real parts, and -) pomeron and odderon, the participants have addressed many other subjects such as: -) LHC physics, -) non-perturbative approaches to high-energy scattering, -) the dipole model, -) small-x evolution, -) hard diffraction in QCD, -) nuclear shadowing, -) diffractive Higgs studies, -) spin effects, -) 4-quarks and 5-quarks, or -) B-physics.
Search for photon–photon elastic scattering in the X-ray region
International Nuclear Information System (INIS)
Inada, T.; Yamaji, T.; Adachi, S.; Namba, T.; Asai, S.; Kobayashi, T.; Tamasaku, K.; Tanaka, Y.; Inubushi, Y.; Sawada, K.; Yabashi, M.; Ishikawa, T.
2014-01-01
We report the first results of a search for real photon–photon scattering using X rays. A novel system is developed to split and collide X-ray pulses by applying interferometric techniques. A total of 6.5×10 5 pulses (each containing about 10 11 photons) from an X-ray Free-Electron Laser are injected into the system. No scattered events are observed, and an upper limit of 1.7×10 −24 m 2 (95% C.L.) is obtained on the photon–photon elastic scattering cross section at 6.5 keV
The polarization of MeV neutrons elastically scattered from 4He
International Nuclear Information System (INIS)
Bond, J.E.; Firk, F.W.K.
1976-01-01
The analyzing power of 4 He for neutron elastic scattering has been measured at four angles between 20 0 and 80 0 (lab) throughout the energy range 1.5-6.0 MeV using a double-scattering method. The intense flux of polarized neutrons was generated via the reactions Pb(γ, n)→ 12 C(n, n(pol.) 12 C, and the magnitude of the polarization of the neutron beam measured absolutely in a separate double-scattering experiment. Neutron energies were determined with a nanosecond time-of-flight spectrometer, and the generalized neutron spin-precession method was used to minimize systematic uncertainties. (Auth.)
11. international conference on elastic and diffractive scattering: towards high energy frontiers
International Nuclear Information System (INIS)
2005-01-01
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
Chemical shift of neutron resonances and some ideas on neutron resonances and scattering theory
International Nuclear Information System (INIS)
Ignatovich, V.K.; )
2002-01-01
The dependence of positions of neutron resonances in nuclei in condensed matter on chemical environment is considered. A possibility of theoretical description of neutron resonances, different from R-matrix theory is investigated. Some contradictions of standard scattering theory are discussed and a new approach without these contradictions is formulated [ru
Resonant inelastic x-ray scattering studies of elementary excitations
Ament, Lucas Johannes Peter (Luuk)
2010-01-01
Resonant Inelastic X-ray Scattering (RIXS) is an X-ray in, X-ray out technique that enables one to study the dispersion of excitations in solids. In this thesis, we investigated how various elementary excitations of transition metal oxides show up in RIXS spectra.
Electron scattering from CO in the 2Pi resonance region
International Nuclear Information System (INIS)
Buckman, S.J.; Lohmann, B.
1986-01-01
The total cross section for electron scattering from CO in the energy range 0.5--5 eV has been measured with use of a time-of-flight spectrometer. This energy region encompasses the 2 π shape resonance, and a comparison is made with other experimental and theoretical results with regard to the magnitude and position of this structure
Ideal Gas Resonance Scattering Kernel Routine for the NJOY Code
International Nuclear Information System (INIS)
Rothenstein, W.
1999-01-01
In a recent publication an expression for the temperature-dependent double-differential ideal gas scattering kernel is derived for the case of scattering cross sections that are energy dependent. Some tabulations and graphical representations of the characteristics of these kernels are presented in Ref. 2. They demonstrate the increased probability that neutron scattering by a heavy nuclide near one of its pronounced resonances will bring the neutron energy nearer to the resonance peak. This enhances upscattering, when a neutron with energy just below that of the resonance peak collides with such a nuclide. A routine for using the new kernel has now been introduced into the NJOY code. Here, its principal features are described, followed by comparisons between scattering data obtained by the new kernel, and the standard ideal gas kernel, when such comparisons are meaningful (i.e., for constant values of the scattering cross section a 0 K). The new ideal gas kernel for variable σ s 0 (E) at 0 K leads to the correct Doppler-broadened σ s T (E) at temperature T
Elastic and inelastic scattering of alpha particles from sup 46 Ti at E sub. alpha. = 35 MeV
Energy Technology Data Exchange (ETDEWEB)
Raghunatha Rao, V.; Sudarshan, M.; Sarma, A.; Singh, R. (North-Eastern Hill Univ., Shillong (India). Dept. of Physics); Banerjee, S.R.; Chintalapudi, S.N. (Bhabha Atomic Research Centre, Bombay (India). Variable Energy Cyclotron Project)
1991-12-01
Differential cross sections for elastic and inelastic scattering of 35 MeV alpha particles have been measured from {theta}{sub lab} =10{sup o} to 100{sup o} in 1{sup o}-2{sup o} steps. An optical model analysis of the elastic scattering data has been carried out using Woods-Saxon and Woods-Saxon squared radial dependences for real as well as imaginary parts of the potential. The most sensitive region of the potential in predicting the elastic scattering cross sections has been determined using a notch perturbation test. The problem of discrete family ambiguity in the optical model analysis of elastic data has also been investigated. The inelastic scattering data have been analysed in terms of the collective model using the distorted-wave Born approximation (DWBA), where the distorted waves are generated by the optical potential obtained from the elastic scattering data. (author).
Resonant scattering in the presence of an electromagnetic field
International Nuclear Information System (INIS)
Rosenberg, L.
1983-01-01
The theory of resonant reactions, in the projection-operator formulation of Feshbach, is generalized to account for the presence of an external electromagnetic field. The theory is used as the basis for the construction of low-frequency approximations for the transition amplitude. Results obtained here for scattering in a laser field confirm earlier versions of the low-frequency approximation when the resonances are isolated. However, if there are several closely spaced resonances additional terms must be included (their importance magnified by the appearance of near singularities) which account for the effect of radiative transitions between pairs of nearly degenerate resonant states. The weak-field limit of this result yields a low-frequency approximation for single-photon spontaneous bremsstrahlung which, through the inclusion of correction terms associated with closely spaced resonances, provides an improvement over the Feshbach-Yennie version derived some time ago. A separate treatment is required to deal with the limiting case of a static external field and this is worked out here in the context of a time-dependent formulation of the scattering problem. Linear and quadratic Stark splitting of the resonance positions, and resonance broadening due to the tunneling mechanism, are expected to play a significant role in the static limit and these effects are included in the approximation derived here for the transition amplitude
Elastic and inelastic scattering of pions from oxygen-16
International Nuclear Information System (INIS)
Holtkamp, D.B.
1980-02-01
Positive and negative pions of an energy of 164 MeV were used in a scattering experiment at EPICS in a study of the atomic nucleus of 16 O. Angular distributions for the ground state and several excited states are presented for an angular range of 45 0 to 89 0 (lab). Of particular importance in this study is the observation of large asymmetries in the ratio sigma(π + )/sigma(π - ) for excitations of particle-hole states at 17.79 MeV (4 - ,0) and 19.80 MeV (4 - ,0), while the ratio for scattering to the state at 18.98 MeV (4 - ,1) is unity. These results are interpreted in terms of isospin mixing among these three states, yielding off-diagonal charge dependent mixing matrix elements of 188 +- 29 keV and 140 +- 21 keV. DWIA calculations using collective form factors yield deformation lengths in agreement with studies using other probes. Microscopic DWIA calculations for the 4 - states are also presented, which reproduce the π + /π - ratios well be reflect the shape of the angular distributions poorly
Energy Technology Data Exchange (ETDEWEB)
Bigio, I.J.; Loree, T.R.; Mourant, J.; Shimada, T. [Los Alamos National Lab., NM (United States); Story-Held, K.; Glickman, R.D. [Texas Univ. Health Science Center, San Antonio, TX (United States). Dept. of Ophthalmology; Conn, R. [Lovelace Medical Center, Albuquerque, NM (United States). Dept. of Urology
1993-08-01
A non-invasive diagnostic tool that could identify malignancy in situ and in real time would have a major impact on the detection and treatment of cancer. We have developed and are testing early prototypes of an optical biopsy system (OBS) for detection of cancer and other tissue pathologies. The OBS invokes a unique approach to optical diagnosis of tissue pathologies based on the elastic scattering properties, over a wide range of wavelengths, of the microscopic structure of the tissue. The use of elastic scattering as the key to optical tissue diagnostics in the OBS is based on the fact that many tissue pathologies, including a majority of cancer forms, manifest significant architectural changes at the cellular and sub-cellular level. Since the cellular components that cause elastic scattering have dimensions typically on the order of visible to near-IR wavelengths, the elastic (Mie) scattering properties will be strongly wavelength dependent. Thus, morphology and size changes can be expected to cause significant changes in an optical signature that is derived from the wavelength dependence of elastic scattering. The data acquisition and storage/display time with the OBS instrument is {approximately}1 second. Thus, in addition to the reduced invasiveness of this technique compared with current state-of-the-art methods (surgical biopsy and pathology analysis), the OBS offers the possibility of impressively faster diagnostic assessment. The OBS employs a small fiber-optic probe that is amenable to use with any endoscope, catheter or hypodermic, or to direct surface examination (e.g. as in skin cancer or cervical cancer). It has been tested in vitro on animal and human tissue samples, and clinical testing in vivo is currently in progress.
Elastic and inelastic scattering of polarized lithium-7 on magnesium-26
International Nuclear Information System (INIS)
Ott, W.
1986-01-01
The elastic and inelastic scattering of polarized 7 Li on 26 Mg was studied at an incident energy of 44 MeV. Measured were the cross sections and the vector analyzing power, three tensor analysing powers, and a third-stage analyzing power for elastic scattering, projectile excitation, target excitation, and double excitation. The cross sections show just as the largest part of the analyzing powers characteristic Fraunhofer oscillations caused by interferences of nearside and farside scattering. From the analysis of the tensor analyzing powers of the elastic scattering by means of generalized shape-effect relations results that the largest contribution for the tensor analyzing powers arises from a Tsub(R) tensor potential. No indications of other tensor interactions like for instance a Tsub(P) tensor interaction were found. At large scattering angles also an influence of the effective spin-orbit interaction generated by channel couplings on the tensor analyzing powers and interferences of spin-orbit and tensor interaction is to be seen. (orig./HSI) [de
Surface acoustic waves and elastic constants of InN epilayers determined by Brillouin scattering
Energy Technology Data Exchange (ETDEWEB)
Jimenez-Rioboo, R.J.; Prieto, C. [Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, Madrid (Spain); Cusco, R.; Domenech-Amador, N.; Artus, L. [Institut Jaume Almera, Consell Superior d' Investigacions Cientifiques (CSIC), Lluis Sole i Sabaris s.n., Barcelona, Catalonia (Spain); Yamaguchi, T.; Nanishi, Y. [Faculty of Science and Engineering, Ritsumeikan University, Noji-Higashi, Kusatsu, Shiga (Japan)
2012-06-15
The surface acoustic wave velocity in InN has been experimentally determined by means of Brillouin scattering experiments on c - and m -face epilayers. From simulations based on the Green's function formalism we determine the shear elastic constants c{sub 66} and c{sub 44} and propose a complete set of elastic constants for wurtzite InN. The analysis of the sagittal and azimuthal dependence of the surface acoustic wave velocity indicates a slightly different elastic behavior of the m -face sample that basically affects the c{sub 44} elastic constant. (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)
Analysis of the elastic scattering of negative muons from atomic hydrogen
International Nuclear Information System (INIS)
Muller, R.J.
1977-01-01
The total elastic cross section and the transport cross section for the scattering of negative muons from the hydrogen atom is determined by making a partial wave analysis of the elastic scattering amplitude. An effective Schrodinger equation for the muon-hydrogen system is obtained, using a static model of the field of the hydrogen atom, and its numerical solution allows the phase shifts for fifty partial waves to be obtained over a wide range of energies. A polarization potential term is then included, and the results of the scattering from the effective potential obtained are compared with the results from the static field. The results show a substantial effect of the polarization in the cross sections at low energy. The analysis of the low energy behavior of the phase shifts indicates that a substantial number of bound states for the muon exist in both the static and the static + polarization fields of hydrogen
Elastic scattering of antiprotons on 4He at 600 MeV/c
International Nuclear Information System (INIS)
Batusov, Yu.A.; Bunyatov, S.A.; Pontekorvo, D.B.
1990-01-01
The differential cross sections for antiproton elastic scattering on 4 He at 607.7 MeV/c are measured. The total elastic cross section σ el =120.9±2.5 mb and the total p-bar 4 He interaction cross section σ tot =360.1±5.6 mb are determined. Partial wave analysis reveals that the P,D and F waves are dominant in the scattering. The angular dependence of Differential cross sections exhibits the diffraction pattern typical of scattering on a strongly absorbing disk. Simply taking into account diffuseness of the black disk edge provides good agreement of calculations with the experimental data
Elastic scattering of antiprotons on 4He at 600 MeV/c
International Nuclear Information System (INIS)
Batusov, Yu.A.; Bunyatov, S.A.; Falomkin, I.V.
1990-01-01
The differential cross section for antiproton elastic scattering on 4 He at 607.7 MeV/c momentum is measured. The total elastic cross section σ el =(120.9±2.5) mb and the total p -4 He interaction cross section σ tot =(360.1±5.6) mb are determined. Partial wave analysis reveals that the P,D and F-waves are dominant in the scattering. The angular dependence of differential cross section exhibits the diffraction pattern typical of scattering on a strongly absorbing disk. Simply taking into account diffuseness of the disk provides good agreement of calculations with the experimental data. 17 refs.; 8 figs.; 1 tab
Analysis and characterization. Nuclear resonant scattering with the synchrotron radiation
International Nuclear Information System (INIS)
Ruffer, R.; Teillet, J.
2003-01-01
The nuclear resonant scattering using the synchrotron radiation combines the uncommon properties of the Moessbauer spectroscopy and those of the synchrotron radiation. Since its first observation in 1984, this technique and its applications have been developed rapidly. The nuclear resonant scattering is now a standard technique for all the synchrotron radiation sources of the third generation. As the Moessbauer spectroscopy, it is a method of analysis at the atomic scale and a non destructive method. It presents the advantage not to require the use of radioactive sources of incident photons which can be difficult to make, of a lifetime which can be short and of an obviously limited intensity. The current applications are the hyperfine spectroscopy and the structural dynamics. In hyperfine spectroscopy, the nuclear resonant scattering can measure the same size than the Moessbauer spectroscopy. Nevertheless, it is superior in the ranges which exploit the specific properties of the synchrotron radiation, such as the very small samples, the monocrystals, the measures under high pressures, the geometry of small angle incidence for surfaces and multilayers. The structural dynamics, in a time scale of the nanosecond to the microsecond can be measured in the temporal scale. Moreover, the nuclear inelastic scattering gives for the first time a tool which allows to have directly the density of states of phonons and then allow to deduce the dynamical and thermodynamical properties of the lattice. The nuclear resonant scattering technique presented here, which corresponds to the Moessbauer spectroscopy technique (SM), is called 'nuclear forward scattering' (NFS). Current applications in physics and chemistry are develop. The NFS is compared to the usual SM technique in order to reveal its advantages and disadvantages. (O.M.)
Photon induced resonant Raman scattering in CdS
International Nuclear Information System (INIS)
Muzart, J.; Lluesma, E.G.; Arguello, C.A.; Leite, R.C.C.
1975-01-01
A novel aspect of resonant Raman scattering is observed in CdS by means of the ratio of Stokes to anti-Stokes intensities. With increasing temperature, as the forbidden band energy approaches a value that is twice the incident photon energy, (from a Nd-Yag-laser) a large enhancement of the above ratio is observed for both the LO and the 2LO phonon Raman intensities. The results indicate a resonance with the scattered photon. Resonance is only observed for high incident photon intensities. A possible explanation for the above observations is that flooding of the crystal with photons of energy hν induces states of energy hν displaced from the electronic bands by mixing of electronic and photon states
Study of inelastic proton scattering at isobaric analog resonances
International Nuclear Information System (INIS)
Davis, S.L.
1974-01-01
Inelastic proton scattering at isobaric analog resonances (IAR's) was studied using the targets 138 Ba and 92 Mo. Differential cross sections and analyzing powers were measured at the 10.00, 10.63, 11.09, 11.45, and 11.70 MeV resonances in 138 Ba + p and at the 5.89, 6.09, and 6.55 MeV resonances in 92 Mo + p. In addition, a new measurement, the spin flip asymmetry, was developed. The experiment was performed by using a polarized beam to make spin flip measurements. Angular distributions for the spin flip probability and spin flip asymmetry were measured at all of the above energies except for the lowest three resonances in 138 Ba, where only the spin flip probability was measured. A DWBA code modified to include the coherent addition of resonance amplitudes was used to analyze the 138 Ba data. The partial widths extracted from this analysis were converted to expansion coefficients for parent states in 139 Ba. The coefficients were found to be in good agreement with unified model calculations. For 92 Mo, inelastic polarizations, deduced from the spin flip and spin flip asymmetry, were found to be large. Attempts using Hauser Feshbach theory to describe both the cross section and polarization data repeatedly failed for both the 6.55 and 5.87 MeV IAR's. This failure represents strong evidence that Hauser Feshbach theory is not valid when extended to describe scattering at an IAR. The 92 Mo data were analyzed using a reaction theory modified to include channel-channel correlations. This theory predicts that the enhanced compound scattering is identical to the resonance scattering. Good fits have been obtained with the use of this modified Hauser Feshbach theory. (U.S.)
Regge poles and alpha scattering
International Nuclear Information System (INIS)
Ceuleneer, R.
1974-01-01
The direct Regge pole model as a means of describing resonances in elastic particle scattering has been used for the analysis of the so-called ''anormalous large angle scattering'' of alpha particles by spinless nuclei. (Z.M.)
Resonant X-Ray Scattering and the jeff=1/2 Electronic Ground State in Iridate Perovskites
DEFF Research Database (Denmark)
Sala, M. Moretti; Boseggia, S.; McMorrow, Desmond Francis
2014-01-01
The resonant x-ray scattering (magnetic elastic, RXMS, and inelastic, RIXS) of Ir4+ at the L-2,L-3 edges relevant to spin-orbit Mott insulators A(n+1) Ir(n)O3(n+1) (A = Sr, Ba, etc.) are calculated using a single-ion model which treats the spin-orbit and tetragonal crystal-field terms on an equal...
Proportional Counter Calibration and Analysis for 12C + p Resonance Scattering
Nelson, Austin; Rogachev, Grigory; Uberseder, Ethan; Hooker, Josh; Koshchiy, Yevgen
2014-09-01
Light exotic nuclei provide a unique opportunity to test the predictions of modern ab initio theoretical calculations near the drip line. In ab initio approaches, nuclear structure is described starting from bare nucleon-nucleon and three-nucleon interactions. Calculations are very heavy and can only be performed for the lightest nuclei (A objective of this project was to test the performance and perform position calibration of this proportional counter array. The test was done using 12C beam. The excitation function for 12C + p elastic scattering was measured and calibration of the proportional counter was performed using known resonances in 13N. The method of calibration, including solid angle calculations, normalization corrections, and position calibration will be presented. Light exotic nuclei provide a unique opportunity to test the predictions of modern ab initio theoretical calculations near the drip line. In ab initio approaches, nuclear structure is described starting from bare nucleon-nucleon and three-nucleon interactions. Calculations are very heavy and can only be performed for the lightest nuclei (A objective of this project was to test the performance and perform position calibration of this proportional counter array. The test was done using 12C beam. The excitation function for 12C + p elastic scattering was measured and calibration of the proportional counter was performed using known resonances in 13N. The method of calibration, including solid angle calculations, normalization corrections, and position calibration will be presented. Funded by DOE and NSF-REU Program; Grant No. PHY-1263281.
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...
Support Minimized Inversion of Acoustic and Elastic Wave Scattering
Safaeinili, Ali
Inversion of limited data is common in many areas of NDE such as X-ray Computed Tomography (CT), Ultrasonic and eddy current flaw characterization and imaging. In many applications, it is common to have a bias toward a solution with minimum (L^2)^2 norm without any physical justification. When it is a priori known that objects are compact as, say, with cracks and voids, by choosing "Minimum Support" functional instead of the minimum (L^2)^2 norm, an image can be obtained that is equally in agreement with the available data, while it is more consistent with what is most probably seen in the real world. We have utilized a minimum support functional to find a solution with the smallest volume. This inversion algorithm is most successful in reconstructing objects that are compact like voids and cracks. To verify this idea, we first performed a variational nonlinear inversion of acoustic backscatter data using minimum support objective function. A full nonlinear forward model was used to accurately study the effectiveness of the minimized support inversion without error due to the linear (Born) approximation. After successful inversions using a full nonlinear forward model, a linearized acoustic inversion was developed to increase speed and efficiency in imaging process. The results indicate that by using minimum support functional, we can accurately size and characterize voids and/or cracks which otherwise might be uncharacterizable. An extremely important feature of support minimized inversion is its ability to compensate for unknown absolute phase (zero-of-time). Zero-of-time ambiguity is a serious problem in the inversion of the pulse-echo data. The minimum support inversion was successfully used for the inversion of acoustic backscatter data due to compact scatterers without the knowledge of the zero-of-time. The main drawback to this type of inversion is its computer intensiveness. In order to make this type of constrained inversion available for common use, work
International Nuclear Information System (INIS)
Bray, Igor; Konovalov, D.A.; McCarthy, I.E.
1991-04-01
A coupled-channel optical method for electron-atom scattering is applied to elastic electron-sodium scattering at energies of 20, 22.1, 54.4, 100, and 150 eV. It is demonstrated that the effect of all the inelastic channels on elastic scattering may be well reproduced by the 'ab initio' calculated complex non-local polarization potential. Whilst the experiments generally agree at small angles and therefore agree on the total elastic cross section, there is considerable discrepancy at intermediate and backward angles. 9 refs., 2 tabs., 1 fig
Resonant proton scattering of $^{22}$Mg and $^{21}$Na
Di julio, D D; Jansson, K; Rudolph, D; Fynbo, H O U; Nilsson, T; Perea martinez, A
In our letter-of-intent, INTC-I-051, we discussed the physics case for scattering and transfer reactions involving light nuclei in the break-out region of the rp-process. The Committee found the physics case compelling and supported the letter-of-intent under the premise that beams of proper quality were developed and that an adequate detector set-up was presented. As these two requirements have been met recently we now propose to study resonant proton scattering of $^{22}$Mg to identify the states at 1.733 MeV and 2.575 MeV in $^{23}$Al that have been reported from the $^{24}$Mg($^{7}$Li,$^{8}$He)$\\,^{23}\\!$Al reaction but that remained unobserved in the only resonant proton scattering experiment performed with $^{22}$Mg so far. In particular we should be able to investigate the character of the proton emission of the 2.575 MeV state which may also have a significant inelastic branch. We also propose to perform resonant proton scattering on $^{21}$Na above $\\alpha$-particle threshold with $^{18}$Ne to study ...
Theory of inelastic effects in resonant atom-surface scattering
International Nuclear Information System (INIS)
Evans, D.K.
1983-01-01
The progress of theoretical and experimental developments in atom-surface scattering is briefly reviewed. The formal theory of atom-surface resonant scattering is reviewed and expanded, with both S and T matrix approaches being explained. The two-potential formalism is shown to be useful for dealing with the problem in question. A detailed theory based on the S-matrix and the two-potential formalism is presented. This theory takes account of interactions between the incident atoms and the surface phonons, with resonant effects being displayed explicitly. The Debye-Waller attenuation is also studied. The case in which the atom-surface potential is divided into an attractive part V/sub a/ and a repulsive part V/sub r/ is considered at length. Several techniques are presented for handling the scattering due to V/sub r/, for the case in which V/sub r/ is taken to be the hard corrugated surface potential. The theory is used to calculate the scattered intensities for the system 4 He/LiF(001). A detailed comparison with experiment is made, with polar scans, azimuthal scans, and time-of-flight measurements being considered. The theory is seen to explain the location and signature of resonant features, and to provide reasonable overall agreement with the experimental results
Structure of high excited nuclear states and elastic scattering
International Nuclear Information System (INIS)
Zhivopistsev, F.A.; Rzhevskij, E.S.
1979-01-01
An approach to a unified description of nuclear reactions and nuclear structure based on the formalism of the quantum Green functions and on the ideas of the theory of finite Fermi systems has been formulated. New structural vertices are introduced, which are responsible for nucleon collectivization in an atomic nucleus and for the excitation of many-phonon, quasideuteron, quasitriton and other configurations. The vertices define both the processes of particle scattering by atomic nuclei (T matrix and optical potentials) and the nuclear structure (secular equations and wave functions). The vertices are determined from the equations with effective many-particle forces Fsub(nm)sup(c). In their turn the Fsub(nm)sup(c) forces are either determined from a comparison of theory and experiment, or calculated from the equations with more fundamental nucleon-nucleon forces in a nucleus. The effective forces Fsub(nm)sup(c) are more universal than the constants of the theory of finite Fermi-systems, which extends the boundaries of applicability of the particle-hole formalism in the description of nuclear processes. In this approach the traditional methods of description of the nuclear structure, based on particular models of hamiltonian and wave functions, acquire a natural interpretation
Resonant magnetic scattering of polarized soft x rays
Energy Technology Data Exchange (ETDEWEB)
Sacchi, M. [Centre Universitaire Paris-Sud, Orsay (France); Hague, C.F. [Universite Pierre et Marie Curie, Paris (France); Gullikson, E.M.; Underwood, J. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States)
1997-04-01
Magnetic effects on X-ray scattering (Bragg diffraction, specular reflectivity or diffuse scattering) are a well known phenomenon, and they also represent a powerful tool for investigating magnetic materials since it was shown that they are strongly enhanced when the photon energy is tuned across an absorption edge (resonant process). The resonant enhancement of the magnetic scattering has mainly been investigated at high photon energies, in order to match the Bragg law for the typical lattice spacings of crystals. In the soft X-ray range, even larger effects are expected, working for instance at the 2p edges of transition metals of the first row or at the 3d edges of rare earths (300-1500 eV), but the corresponding long wavelengths prevent the use of single crystals. Two approaches have been recently adopted in this energy range: (i) the study of the Bragg diffraction from artificial structures of appropriate 2d spacing; (ii) the analysis of the specular reflectivity, which contains analogous information but has no constraints related to the lattice spacing. Both approaches have their own specific advantages: for instance, working under Bragg conditions provides information about the (magnetic) periodicity in ordered structures, while resonant reflectivity can easily be related to electronic properties and absorption spectra. An important aspect common to all the resonant X-ray scattering techniques is the element selectivity inherent to the fact of working at a specific absorption edge: under these conditions, X-ray scattering becomes in fact a spectroscopy. Results are presented for films of iron and cobalt.
Isotopic effects in elastic and inelastic 12,13C + 16,18O scattering
Directory of Open Access Journals (Sweden)
A. T. Rudchik
2010-09-01
Full Text Available New angular-distribution data of 13С + 18О elastic and inelastic scattering at the energy Elab(18O = 105 MeV were obtained for the transitions to the ground and excited states 3.088 MeV(1/2+, 3.555 MeV (1/2-, 3.854 MeV (5/2+ of 13С and 1.982 MeV (2+, 3.555 MeV (4+, 3.921 MeV (2+, 4.456 MeV (1-, 5.098 MeV (3-, 5.260 MeV (2+ of 18O. These and the 13С + 18О elastic scattering data taken from the literature at the energies Elab(18O = 15, 20, 24, 31 MeV and Elab(13С = 24 MeV were analysed within the optical model and coupled-reaction-channels methods. Sets of 13С + 18О optical potential parameters and their energy dependence were obtained. Contributions of potential scattering and transfer reactions to the elastic and inelastic channels of 13С + 18О scattering were studied. Isotopic differences (effects in 12, 13С + 16, 18О optical potential parameters were investigated.
s-wave elastic scattering of antihydrogen off atomic alkali-metal targets
International Nuclear Information System (INIS)
Sinha, Prabal K.; Ghosh, A. S.
2006-01-01
We have investigated the s-wave elastic scattering of antihydrogen atoms off atomic alkali-metal targets (Li, Na, K, and Rb) at thermal energies (10 -16 -10 -4 a.u.) using an atomic orbital expansion technique. The elastic cross sections of these systems at thermal energies are found to be very high compared to H-H and H-He systems. The theoretical models employed in this study are so chosen to consider long-range forces dynamically in the calculation. The mechanism of cooling suggests that Li may be considered to be a good candidate as a buffer gas for enhanced cooling of antihydrogen atoms to ultracold temperature
Threshold anomaly in the elastic scattering of 6He on 209Bi
International Nuclear Information System (INIS)
Garcia, A. R.; Padron, I.; Lubian, J.; Gomes, P. R. S.; Lacerda, T.; Garcia, V. N.; Gomez-Camacho, A.; Aguilera, E. F.
2009-01-01
The energy dependence of the optical potential for the elastic scattering of 6 He on 209 Bi at near and subbarrier energies is studied. Elastic angular distributions and the reaction cross section were simultaneously fitted by performing some modifications in the ECIS code. A phenomenological optical model potential with the Woods-Saxon form was used. There are signatures that the so called breakup threshold anomaly (BTA) is present in this system having a halo projectile 6 He, as it had been found earlier for systems involving stable weakly bound nuclei. (Author)
Analysis of elastic scattering in anti pp interactions at 22.4 Gev/c
International Nuclear Information System (INIS)
Batyunya, E.V.; Boguslavskij, I.V.; Bruntsko, D.
1985-01-01
Results are presented on measuring the anti pp elastic scattering differential cross section at 22.4 GeV/c over a region of 0.05 2 . The results have been obtained from pictures of the HBC ''Ludmila''. The total elastic cross section σsub(el)=9.0+-0.3 mb and the slope parameter b(s, t=0)=13.1+-0.8 GeVsup(-2) have been found from the data approximated by a quadratic exponential function. The results are compared with the data at similar energies
Forward two-photon exchange in elastic lepton-proton scattering and hyperfine-splitting correction
Energy Technology Data Exchange (ETDEWEB)
Tomalak, Oleksandr [Johannes Gutenberg Universitaet, Institut fuer Kernphysik and PRISMA Cluster of Excellence, Mainz (Germany)
2017-08-15
We relate the forward two-photon exchange (TPE) amplitudes to integrals of the inclusive lepton-proton scattering cross sections. These relations yield an alternative way for the evaluation of the TPE correction to hyperfine-splitting (HFS) in the hydrogen-like atoms with an equivalent to the standard approach (Iddings, Drell and Sullivan) result implying the Burkhardt-Cottingham sum rule. For evaluation of the individual effects (e.g., elastic contribution) our approach yields a distinct result. We compare both methods numerically on examples of the elastic contribution and the full TPE correction to HFS in electronic and muonic hydrogen. (orig.)
Study of 11Li and 10,11Be nuclei through elastic scattering and breakup reactions
Gaidarov, M. K.; Lukyanov, V. K.; Kadrev, D. N.; Zemlyanaya, E. V.; Antonov, A. N.; Lukyanov, K. V.; Spasova, K.
2016-01-01
The hybrid model of the microscopic optical potential (OP) is applied to calculate the 11Li+p, 10,11Be+p, and 10,11Be+12C elastic scattering cross sections at energies E energy approximation (HEA) theory. For the 11Li+p elastic scattering, the microscopic large-scale shell model (LSSM) density of 11Li is used, while the density distributions of 10,11Be nuclei obtained within the quantum Monte Carlo (QMC) model and the generator coordinate method (GCM) are utilized to calculate the microscopic OPs and cross sections of elastic scattering of these nuclei on protons and 12C. The depths of the real and imaginary parts of OP are fitted to the elastic scattering data, being simultaneously adjusted to reproduce the true energy dependence of the corresponding volume integrals. Also, the cluster models, in which 11Li consists of 2n-halo and the 9Li core having its own LSSM form of density and 11Be consists of a n-halo and the 10Be core, are adopted. Within the latter, we give predictions for the longitudinal momentum distributions of 9Li fragments produced in the breakup of 11Li at 62 MeV/nucleon on a proton target. It is shown that our results for the diffraction and stripping reaction cross sections in 11Be scattering on 9Be, 93Nb, 181Ta, and 238U targets at 63 MeV/nucleon are in a good agreement with the available experimental data.
Study of 11Li and 10,11Be nuclei through elastic scattering and breakup reactions
Directory of Open Access Journals (Sweden)
Gaidarov M. K.
2016-01-01
Full Text Available The hybrid model of the microscopic optical potential (OP is applied to calculate the 11Li+p, 10,11Be+p, and 10,11Be+12C elastic scattering cross sections at energies E < 100 MeV/nucleon. The OP’s contain the folding-model real part (ReOP with the direct and exchange terms included, while its imaginary part (ImOP is derived within the high-energy approximation (HEA theory. For the 11Li+p elastic scattering, the microscopic large-scale shell model (LSSM density of 11Li is used, while the density distributions of 10,11Be nuclei obtained within the quantum Monte Carlo (QMC model and the generator coordinate method (GCM are utilized to calculate the microscopic OPs and cross sections of elastic scattering of these nuclei on protons and 12C. The depths of the real and imaginary parts of OP are fitted to the elastic scattering data, being simultaneously adjusted to reproduce the true energy dependence of the corresponding volume integrals. Also, the cluster models, in which 11Li consists of 2n-halo and the 9Li core having its own LSSM form of density and 11Be consists of a n-halo and the 10Be core, are adopted. Within the latter, we give predictions for the longitudinal momentum distributions of 9Li fragments produced in the breakup of 11Li at 62 MeV/nucleon on a proton target. It is shown that our results for the diffraction and stripping reaction cross sections in 11Be scattering on 9Be, 93Nb, 181Ta, and 238U targets at 63 MeV/nucleon are in a good agreement with the available experimental data.
Local and non-local potentials for deuteron elastic scattering
International Nuclear Information System (INIS)
Ramirez, J.A.
1976-01-01
The nucleon--nucleus local potential (central and spin--orbit) and the deuteron--nucleus nonlocal potential (central, spin--orbit, spin--radial tensor) are calculated by the folding-model (FM). Simple analytic expressions are obtained for the nucleon--nucleus potential by the use of Gaussians to represent the nucleon--nucleus potential and the charge and mass densities of the target. The analytic expressions give qualitative descriptions of phenomenological nucleon--nucleus interactions. A systematic target--mass dependence of realistic local FM deueron potentials is also included. Local-equivalent, energy-dependent, deuteron potentials are obtained from the nonlocal FM deuteron potentials and the energy dependence of the local potential parameters are presented. The local FM deuteron potential is tested for 60 Ni(d,d) 60 Ni at E/sub α/ = 15 MeV by comparing the predictions of the FM potentials with data in which all five polarization moments were measured. A qualitative fit to the data is obtained, but it overestimates the volume integral of the central potential by 7%. Energy-dependence effects are estimated by evaluating the local-equivalent potentials at E/sub α/ = 30 MeV and comparing the predictions to the E/sub α/ = 15 MeV potentials. The energy dependence of the central potential dominates the angular dependence of all five observables while the energy dependence of the spin--orbit and tensor potentials produces only scale changes (approx. 3%) in the vector and tensor analyzing powers. The scattering formalism for a spin-1 on a spin-0 target nucleus, and a description of the coupled--channels computer code DDUNC1 which treats the spin--radial tensor potential exactly, are included
Exchange current contributions to quasi-elastic electron scattering
International Nuclear Information System (INIS)
Conte, J.S. Jr.
1981-01-01
Because electromagnetic interactions are weak and well understood, inelastic electron scattering has been very useful in elucidating aspects of nuclear structure. In the region of large electron energy loss, an extremely simple reaction picture (quasi-free knockout of a single nucleon or electroproduction of an isobar) and a simple nuclear model (Fermi gas) have provided both a good fit to experimental data and a dynamical determination of the nuclear Fermi momentum (k/sub F/). However, there exists an anomalous region where this picture fails. Two body correlations have not seemed to help give any better agreement. We have investigated the following questions: Do exchange current processes contribute importantly in this region. Do they help produce agreement with experiment. Also, how do they effect our previous picture of quasifree knockout. We calculate the effects of exchange currents in this region using the standard Feynman graph rules. We have included all important long range exchange currents: pair, pionic, and isobar exchange currents. We found it necessary to make non-relativistic reductions of these currents in order to facilitate calculations. The resulting multidimensional integrals were done using Monte Carlo techniques. All exchange currents which were investigated were found to be appreciable in the anomalous region, and also important in the quasi-free peak region. Inclusion of these amplitudes would supply all of the missing cross section in the anomalous region: however, it would destroy the agreement between theory and experiment in the region of the quasi-free nucleon peak, and thereby cast suspicion on the aforementioned dynamical determination of k/sub F/
Assessment of Coulomb shifts in nucleon scattering resonances on light nuclei at low energies
International Nuclear Information System (INIS)
Takibaev, N.Zh.; Uzakova, Zh.; Abdanova, L.
2003-01-01
The assessments of the Coulomb forces contribution to position and width of the resonances at nucleons scattering on light nuclei within low energy field are given. In particular the shifts of resonances in amplitudes arising in the processes protons scattering on light nuclei relatively neutrons scattering resonance characteristics on these nuclei are considered
Stochastic modelling of fusion-product transport and thermalization with nuclear elastic scattering
International Nuclear Information System (INIS)
Deveaux, J.C.
1983-01-01
Monte Carlo methods are developed to model fusion-product (fp) transport and thermalization with both Rutherford scattering and nuclear elastic scattering (NES) in high-temperature (T/sub i/, T/sub e-/ > 50 keV), advanced-fuel (e.g. Cat-D, D- 3 He) plasmas. A discrete-event model is used to superimpose NES collisions on a Rutherford scattering model that contains the Spitzer coefficients of drag, velocity diffusion (VD), and pith-angle scattering (PAS). The effects of NES on fp transport and thermalization are investigated for advanced-fuel, Field-Reversed Mirror (FRM) plasmas that have a significant Hamiltonian-canonical angular momentum (H-Ptheta) space loss cone which scales with the characteristic size (S identical with R/sub HV//3p/sub i/) and applied vacuum magnetic field (B 0 )
On the influence of resonance photon scattering on atom interference
International Nuclear Information System (INIS)
Bozic, M; Arsenovic, D; Sanz, A S; Davidovic, M
2010-01-01
Here, the influence of resonance photon-atom scattering on the atom interference pattern at the exit of a three-grating Mach-Zehnder interferometer is studied. It is assumed that the scattering process does not destroy the atomic wave function describing the state of the atom before the scattering process takes place, but only induces a certain shift and change of its phase. We find that the visibility of the interference strongly depends on the statistical distribution of transferred momenta to the atom during the photon-atom scattering event. This also explains the experimentally observed (Chapman et al 1995 Phys. Rev. Lett. 75 2783) dependence of the visibility on the ratio d p /λ i =y' 12 (2π/kdλ i ), where y' 12 is the distance between the place where the scattering event occurs and the first grating, k is the wave number of the atomic centre-of-mass motion, d is the grating constant and λ i is the photon wavelength. Furthermore, it is remarkable that photon-atom scattering events happen experimentally within the Fresnel region, i.e. the near-field region, associated with the first grating, which should be taken into account when drawing conclusions about the relevance of 'which-way' information for the interference visibility.
Energy Technology Data Exchange (ETDEWEB)
Stöhr, J.; Scherz, A.
2016-01-06
X-ray absorption by matter has long been described by the famous Beer-Lambert law. Here we show how this fundamental law needs to be modified for high-intensity coherent x-ray pulses, now available at x-ray free electron lasers, due to the onset of stimulated elastic forward scattering. We present an analytical expression for the modified polarization-dependent Beer-Lambert law for the case of resonant core-to-valence electronic transitions and incident transform limited x-ray pulses. Upon transmission through a solid, the absorption and dichroic contrasts are found to vanish with increasing x-ray intensity, with the stimulation threshold lowered by orders of magnitude through a super-radiative coherent effect. Our results have broad implications for the study of matter with x-ray lasers.
International Nuclear Information System (INIS)
Linssen, L.H.A.J.
1986-01-01
In this thesis two low-momentum antiproton-proton (anti pp) experiments are described. The first one is a set of 24 high statistics anti pp total cross section measurements as a function of the incoming antiproton momentum between p=388 MeV/c and p=599 MeV/c. These measurements simultaneously yield the charge exchange cross section (anti pp → anti nn). The second one comprises two high statistics anti pp small-angle elastic scattering measurements at p=233 MeV/c and p=272 MeV/c. The measurements were carried out using the high quality antiproton beam extracted from the Low Energy Antiproton Ring (LEAR) at CERN. The physics motivation for these experiments is a search for anti pp resonances or bound states on one hand, and a detailed study of the anti pp interaction on the other hand. (orig.)
Far-field superresolution by imaging of resonance scattering
Schuster, Gerard T.
2014-10-31
We show that superresolution imaging in the far-field region of the sources and receivers is theoretically and practically possible if migration of resonant multiples is employed. A resonant multiple is one that bounces back and forth between two scattering points; it can also be the multiple between two smoothly varying interfaces as long as the reflection wave paths partially overlap and reflect from the same Fresnel zone. For a source with frequency f, compared to a one-way trip, N round trips in propagating between two scatterers increase the effective frequency by 2N × f and decrease the effective wavelength by λ/(2N). Thus, multiples can, in principle, be used as high-frequency probes to estimate detailed properties of layers. Tests with both synthetic and field data validate this claim. Improved resolution by multiple imaging is not only feasible for crustal reflections, but might be applicable to mantle and core reverberations recorded by earthquake seismologists.
Soft X-ray resonant scattering from magnetic heterostructures
International Nuclear Information System (INIS)
Grabis, J.
2005-01-01
Heterogenous magnetic multilayers are of great interest both because of their relevance for technological applications and since they provide model systems to understand magnetic behavior and interactions. Soft x-ray resonant magnetic scattering (XRMS) allows to determine element-specific and depth-resolving information of the local magnetic order of such systems. Within the framework of the present thesis the diffractometer ALICE for soft XRMS has been constructed. XRMS measurements of two different physical systems are presented in this thesis: The antiferromagnetic and ferromagnetic order in interlayer exchange-coupled Fe/Cr(001) superlattices are studied as a function of the applied field by measuring the reflected intensity at different positions in reciprocal space. Thin films and multilayers of the Heusler compound Co 2 MnGe are studied by means of soft x-ray absorption spectroscopy, magnetic circular dichroism and resonant magnetic scattering
Bhatia, Anand K.
2008-01-01
Applications of the hybrid theory to the scattering of electrons from Ile+ and Li++ and resonances in these systems, A. K. Bhatia, NASA/Goddard Space Flight Center- The Hybrid theory of electron-hydrogen elastic scattering [I] is applied to the S-wave scattering of electrons from He+ and Li++. In this method, both short-range and long-range correlations are included in the Schrodinger equation at the same time. Phase shifts obtained in this calculation have rigorous lower bounds to the exact phase shifts and they are compared with those obtained using the Feshbach projection operator formalism [2], the close-coupling approach [3], and Harris-Nesbet method [4]. The agreement among all the calculations is very good. These systems have doubly-excited or Feshbach resonances embedded in the continuum. The resonance parameters for the lowest ' S resonances in He and Li+ are calculated and they are compared with the results obtained using the Feshbach projection operator formalism [5,6]. It is concluded that accurate resonance parameters can be obtained by the present method, which has the advantage of including corrections due to neighboring resonances and the continuum in which these resonances are embedded.
The calibration of elastic scattering angular distribution at low energies on HIRFL-RIBLL
Energy Technology Data Exchange (ETDEWEB)
Zhang, G.X. [School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191 (China); Zhang, G.L., E-mail: zgl@buaa.edu.cn [School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191 (China); Lin, C.J., E-mail: cjlin@ciae.ac.cn [China Institute of Atomic Energy, Beijing 102413 (China); Qu, W.W. [School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191 (China); School of Radiation Medicine and Protection, Medical College of Soochow University, Soochow 215123 (China); Yang, L.; Ma, N.R. [China Institute of Atomic Energy, Beijing 102413 (China); Zheng, L. [School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191 (China); Jia, H.M.; Sun, L.J. [China Institute of Atomic Energy, Beijing 102413 (China); Liu, X.X.; Chu, X.T.; Yang, J.C. [School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191 (China); Wang, J.S.; Xu, S.W.; Ma, P.; Ma, J.B.; Jin, S.L.; Bai, Z.; Huang, M.R. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Zang, H.L. [School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); and others
2017-02-21
The precise calibration of angular distribution of heavy-ion elastic scattering induced by Radioactive Ion Beams (RIBs) at energies around Coulomb barrier on the Radioactive Ion Beam Line in Lanzhou (RIBLL) at the Heavy-Ion Research Facility in Lanzhou (HIRFL) is presented. The beam profile and the scattering angles on the target are deduced by a measurement with two Multi Wire Proportional Chambers (MWPC), and four sets of detector telescopes (including Double-sided Silicon Strip Detectors (DSSD) placed systematically along the beam line, incorporating with Monte Carlo simulation. The MWPCs were used to determine the beam trajectory before the target, and the energies and the positions of scattered particles on the detectors were measured by the DSSDs. Minor corrections on the beam spot and the detector position are performed by assuming the pure Rutherford scattering at angles which are smaller than the related grazing angle. This method is applied for the elastic scattering of {sup 17}F on {sup 89}Y target at E{sub lab}=59 MeV and 50 MeV.
Elastic scattering of polarized protons from 3He at intermediate energies
International Nuclear Information System (INIS)
Hasell, D.K.; Bracco, A.; Gubler, H.P.
1982-09-01
Using the polarized proton beam facility of the TRIUMF cyclotron, differential cross sections and analyzing powers have been measured in the angular range 20 0 - 150 0 c.m. for proton elastic scattering from 3 He at incident proton energies of 200, 300, 415 and 515 MeV. The differential cross sections exhibit a minimum at t = -0.33 (GeV/c) 2 which becomes more pronounced with increasing energy. There is evidence for the onset of a second minimum corresponding to the interference between double and triple scattering amplitudes. Large analyzing powers are observed at the lower energies. The data from the present analysis, together with data obtained from the literature in the energy range 100-1000 MeV, have been analyzed within the framework of the Glauber multiple scattering formalism. Nucleon-nucleon scattering parameters were taken from a global phase shift analysis of nucleon-nucleon elastic scattering data. Reasonable agreement with the data is obtained
International Nuclear Information System (INIS)
Mann, A.K.
1986-01-01
This talk is intended as a brief report on studies of the elastic scattering of neutrinos by protons and electrons. Measurements of the ratios of muon antineutrino and muon neutrino elastic scattering on protons, and the corresponding ratio for elastic scattering on electrons minimize systematic experimental errors, and lead directly to values of the fundamental parameter of the electroweak interaction, the Weinberg Angle, with minimal ambiguity. Accordingly, the principal motivation in carrying out these studies was the desire to obtain and compare precise values of the Weinberg Angle from both the semileptonic and leptonic reactions as still another test of the basic validity of the standard electroweak theory. 10 refs., 11 figs
Relativity, nuclear polarizability, and screening in sub-Coulomb elastic scattering
International Nuclear Information System (INIS)
Lynch, W.G.; Tsang, M.B.; Bhang, H.C.; Cramer, J.G.; Puigh, R.J.
Elastic scattering of p-shell nuclear projectiles from 208 Pb has been examined for deviations from Rutherford scattering. Four effects can be important: atomic screening, vacuum polarization, nuclear polarizability and a relativistic effect of dynamical origin. The presence of atomic screening, nuclear polarizability and the relativistic effect was observed thus constituting the first measurement of this relativistic effect using complex nuclei and the first measurement of this relativistic effect using complex nuclei and the first measurement of nuclear polarizability in an external Coulomb field
Fast-neutron total and elastic-scattering cross sections of elemental indium
International Nuclear Information System (INIS)
Smith, A.B.; Guenther, P.T.; Whalen, J.F.
1982-11-01
Broad-resolution neutron total cross sections of elemental indium were measured from 0.8 to 4.5 MeV. Differential-elastic-scattering cross sections were measured from approx. = 1.5 to 3.8 MeV at intervals of approx. = 50 to 200 keV and at scattering angles in the range 20 to 160 degrees. The experimental results are interpreted in terms of the optical-statistical model and are compared with respective values given in ENDF/B-V
Fast-neutron elastic-scattering cross sections of elemental tin
International Nuclear Information System (INIS)
Budtz-Jorgensen, C.; Guenther, P.T.; Smith, A.
1982-07-01
Broad-resolution neutron-elastic-scattering cross sections of elemental tin are measured from 1.5 to 4.0 MeV. Incident-energy intervals are approx. 50 keV below 3.0 MeV and approx. 200 keV at higher energies. Ten to twenty scattering angles are used, distributed between approx. 20 and 160 0 . The experimental results are used to deduce the parameters of a spherical optical-statistical model and they are also compared with corresponding values given in ENDF/B-V
Elastic scattering of polarized neutrons by 3He at low energy
International Nuclear Information System (INIS)
Drigo, L.; Tornielli, G.; Zannoni, G.
1982-01-01
Elastic scattering by 3 He for 1.67, 2.43, 3.0, 3.4 and 7.8 MeV neutron beams of known polarization was measured at seven angles from 25 0 to 155 0 using a high pressure gas scintillation counter. The geometrical and multiple scattering effects were accounted for by the Monte Carlo technique. The corrected results were compared with previous experimental data and with the existing predictions based on microscopic calculations and phenomenological analyses. (author)
Measurements of spin parameters in p-p elastic scattering at 6 GeV/c
International Nuclear Information System (INIS)
Linn, S.L.; Perlmutter, A.; Crosbie, E.A.; Ratner, L.G.; Schultz, P.F.; O'Fallon, J.R.; Cameron, P.R.; Crabb, D.G.; Fernow, R.C.; Hansen, P.H.; Krisch, A.D.; Salthouse, A.J.; Sandler, B.; Shima, T.; Terwilliger, K.M.
1982-01-01
We measured the differential cross section for proton-proton elastic scattering in 6 GeV/c, with both initial spins oriented normal to the scattering plane. The analyzing power A shows significant structure with a large broad peak reaching about 24% near P/sub perpendicular/ 2 = 1.6 (GeV/c) 2 . The spin-spin correlation parameter A/sub n/n exhibits more dramatic structure, with a small but very sharp peak rising rapidly to about 13% at 90 0 /sub tsc.m./. This sharp peak may be caused by particle-identity effects
International Nuclear Information System (INIS)
Nozaki, Hiroshi
2014-01-01
Ionic conducting behaviors in secondary battery materials, i.e. cathode and solid electrolyte, were studied with quasi-elastic neutron scattering (QENS) measurements. Although the incoherent scattering length for Li and Na is lower by two orders of magnitude than that for H, the QENS spectra were clearly detected using the combination of an intense neutron source and a low background spectrometer. The fundamental parameters, such as, the activation energy, the jump distance, and the diffusion coefficient were obtained by analyzing QENS spectra. These parameters are consistent with the previous results estimated by muon-spin relaxation (μSR) measurements and first principles calculations. (author)
Parity Violation in Elastic Electron-Proton Scattering and the Proton's Strange Magnetic Form Factor
International Nuclear Information System (INIS)
Spayde, D. T.; Averett, T.; Barkhuff, D.; Beck, D. H.; Beise, E. J.; Benson, C.; Breuer, H.; Carr, R.; Covrig, S.; DelCorso, J.
2000-01-01
We report a new measurement of the parity-violating asymmetry in elastic electron scattering from the proton at backward scattering angles. This asymmetry is sensitive to the strange magnetic form factor of the proton as well as electroweak axial radiative corrections. The new measurement of A=-4.92±0.61±0.73 ppm provides a significant constraint on these quantities. The implications for the strange magnetic form factor are discussed in the context of theoretical estimates for the axial corrections. (c) 2000 The American Physical Society
A manifestly reciprocal theory of scattering in the presence of elastic media
International Nuclear Information System (INIS)
Wurmser, D.
1996-01-01
The role of elastic waves in the scattering problem is examined in the context of modern field theory. This effort builds upon a previously published, and since successfully applied formalism for solving the acoustic and electromagnetic scattering problems. It specifically addresses the scattering of acoustic waves from a fluid-solid interface, as well as the scattering of elastodynamic waves from surfaces satisfying the zero-displacement, stress-free, and solid endash solid boundary conditions. Expressions for the change in the scattering amplitude due to a perturbation in the scattering surface are derived directly from the requirement of time reversal symmetry (also known as reciprocity). These results constitute formal statements of the composite (or two-scale) model. In a typical application, the perturbation usually corresponds to Bragg scattering and is treated statistically, while the reference surface provides tilt, shadowing, and multiple scattering, and is usually treated deterministically. Used in this way, the new formalism effectively allows existing numerical and operator expansion methods to be used to calculate the scattering from rougher and/or higher dimensional surfaces than would otherwise be possible. An alternate application of the formalism is illustrated using the fluid-solid boundary as an example. A new manifestly reciprocal expression for the scattering amplitude is presented, as are the small slope and open-quote open-quote local close-quote close-quote two-scale approximations for this problem. (By local, it is meant that only local phenomena such as the tilt of the reference surface are automatically included. However, since the result is manifestly reciprocal, it is fairly straightforward to incorporate a non-local effect such as shadowing.) During the course of the discussion, the classical scattering problem is reexamined from an entirely new perspective
RESONANCES IN THE ISOVECTOR P WAVE OF pi pi SCATTERING
Czech Academy of Sciences Publication Activity Database
Bydžovský, Petr; Surovtsev, Yu .S.; Kaminski, R.; Nagy, M.
2011-01-01
Roč. 26, 3-4 (2011), s. 634-635 ISSN 0217-751X. [11th International Workshop on Meson Production , Properties and Interaction. Krakow, 10.06.2010-15.06.2010] R&D Projects: GA ČR GA202/08/0984 Institutional research plan: CEZ:AV0Z10480505 Keywords : Pion-pion scattering * mesonic resonances * multichannel analysis Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.053, year: 2011
Uncertainty in the inelastic resonant scattering assisted by phonons
International Nuclear Information System (INIS)
Garcia, N.; Garcia-Sanz, J.; Solana, J.
1977-01-01
We have analyzed the inelastic minima observed in new results of He atoms scattered from LiF(001) surfaces. This is done considering bound state resonance processes assisted by phonons. The analysis presents large uncertainties. In the range of uncertainty, we find two ''possible'' bands associated with the vibrations of F - and Li + , respectively. Many more experimental data are necessary to confirm the existence of these processes
Elastic and inelastic scattering of 18O ions on 12C nuclei
Directory of Open Access Journals (Sweden)
A. T. Rudchik
2009-12-01
Full Text Available Angular distributions of the 12C + 18O elastic and inelastic scattering were measured at the energy Elab(18O = 105 MeV (Ec.m. = 42 MeV. These data and data known from the literature at the energies Ec.m. = 12.9 - 56 МеV were analysed within the optical model and coupled-reactionchannels method. The sets of the Woods-Saxon (12С + 18O-potential parameters were deduced and their energy dependence was studied. It was found the isotopic differences in the (12С + 16O- and (12С + 18O-potentials parameters and in their surface forms. The mechanisms of elastic and inelastic (12С + 18O-scattering and role of transfer reactions were studied.
Invariant potential for elastic pion--nucleus scattering. Technical report No. 75-075
International Nuclear Information System (INIS)
Cammarata, J.B.; Banerjee, M.K.
1975-04-01
From the Wick-Dyson expansion of the exact propagator of a pion in the presence of a nucleus an invariant potential for crossing symmetric, elastic pion-nucleus scattering is obtained in terms of a series of pion-nucleon diagrams. The Chew-Low theory is used to develop a model in which the most important class of diagrams is effectively summed. Included in this model is the Exclusion Principle restriction on the pion-bound nucleon interaction, the effects of the binding of nucleons, a kinematic transformation of energy from the lab to the πN center of mass frames, and the Fermi motion and recoil of the target nucleons. From a numerical study of the effects of these processes on the π- 12 C total cross section, the relative importance of each is determined. Other processes contributing to the elastic scattering of pions not included in the present model are also discussed. (9 figures) (U.S.)
A new impact picture for low and high energy proton-proton elastic scattering
International Nuclear Information System (INIS)
Bourrely, C.; Soffer, J.; Wu, Tai Tsun
1978-05-01
The impact picture that was used several years ago to predict the increase of total and integrated differential cross sections at high energies was improved significantly. The major improvements consist of the following: (1) the dependence of the Pomeron term on the momentum transfer is taken from a modified version of the relation between matter distribution and charge distribution; (2) Regge backgrounds are properly taken into account; and (3) a simple non-trivial form is used for the hadronic matter current in the proton. For proton-proton elastic scattering, the phenomenological differential cross section is in good agreement with the experimental data in the laboratory momentum range of 14 GeV/c to 2000 GeV/c, and is predicted for ISABELLE energy. Because of the third improvement, predictions are obtained for both polarization and R parameters for proton-proton elastic scattering
Transverse Beam Spin Asymmetries in Forward-Angle Elastic Electron-Proton Scattering
Energy Technology Data Exchange (ETDEWEB)
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.
Electron-He+ P-wave elastic scattering and photoabsorption in two-electron systems
International Nuclear Information System (INIS)
Bhatia, A. K.
2006-01-01
In a previous paper [A. K. Bhatia, Phys. Rev. A 69, 032714 (2004)], electron-hydrogen P-wave scattering phase shifts were calculated using the optical potential approach based on the Feshbach projection operator formalism. This method is now extended to the singlet and triplet electron-He + P-wave scattering in the elastic region. Phase shifts are calculated using Hylleraas-type correlation functions with up to 220 terms. Results are rigorous lower bounds to the exact phase shifts, and they are compared to phase shifts obtained from the method of polarized orbitals and close-coupling calculations. The continuum functions calculated here are used to calculate photoabsorption cross sections. Photoionization cross sections of He and photodetachment cross sections of H - are calculated in the elastic region--i.e., leaving He + and H in their respective ground states--and compared with previous calculations. Radiative attachment rates are also calculated
Excitation function of elastic scattering on 12C + 4He system, at low energies
International Nuclear Information System (INIS)
Perez-Torres, R.; Aguilera, E. F.; Martinez-Quiroz, E.; Murillo, G.; Belyaeva, T. L.; Maldonado-Velazquez, M.
2011-01-01
Interactions in the 12 C + 4 He system are of great interest in astrophysics and to help determine the relative abundances of elements in stars, at the end of helium burning [1, 2]. The Instituto Nacional de Investigaciones Nucleares (ININ) in Mexico, have made measurements of elastic scattering for this system, using the inverse kinematics method with thick white gas [3, 4], for E CM (0.5 - 4 MeV) θ CM = 180 o . In this work we obtain excitation functions of elastic scattering of 12 C + 4 He system with angular and energy dependence; E CM = 0.5 - 4 MeV and θ CM 100 o -170 o .Using inverse kinematics method with thick white gas and energy loss tables. (Author)
Spin entanglement in elastic electron scattering from quasi-one electron atoms
Fonseca Dos Santos, Samantha; Bartschat, Klaus
2017-04-01
We have extended our work on e-Li collisions to investigate low-energy elastic electron collisions with atomic hydrogen and other alkali targets (Na,K,Rb). These systems have been suggested for the possibility of continuously varying the degree of entanglement between the elastically scattered projectile and the valence electron. In order to estimate how well such a scheme may work in practice, we carried out overview calculations for energies between 0 and 10 eV and the full range of scattering angles 0° -180° . In addition to the relative exchange asymmetry parameter that characterizes the entanglement, we present the differential cross section in order to estimate whether the count rates in the most interesting energy-angle regimes are sufficient to make such experiments feasible in practice. Work supported by the NSF under PHY-1403245.
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.
Electron inelastic scattering by compound nuclei and giant multipole resonances
International Nuclear Information System (INIS)
Dzhavadov, A.V.; Mukhtarov, A.I.; Mirabutalybov, M.M.
1980-01-01
Multipole giant resonances in heavy nuclei have been investigated with the application of the Danos-Greiner dynamic collective theory to the Tassi model. The monopole giant resonance has been studied in 158 Gd, 166 Er, 184 W, 232 Th and 238 V nuclei at the incident electron energy E=200 MeV. Dependences of the form factor square of electron scattering by a 166 Er nucleus on the scattering angle obtained in the distorted-wave high-energy approximation (DWHEA) are presented. Giant dipole and quadrupole resonances in 60 Ni and 90 Zr nuclei have been studied. A comparison has been made of theoretical results obtained in the DWHEA for the dependence of the form factor square on the effective momentum transfer with the experimental data. The analysis of the obtained results led to the following conclusions. To draw a conclusion about the validity of one or another nuclear model and methods for calculating form factors, it is necessary to investigate, both theoretically and experimentally, electron scattering at great angles (THETA>=70 deg). To obtain a good agreement it is necessary to take account of the actual proton and neutron distributions in the ground state and their dynamic properties in an excited state [ru
Measurement of the analysing power of elastic proton-proton scattering at 582 MeV
International Nuclear Information System (INIS)
Berdoz, A.; Favier, B.; Foroughi, F.; Weddigen, C.
1984-01-01
The authors have measured the analysing power of elastic proton-proton scattering at 582 MeV for 14 angles from 20 to 80 0 CM. The angular range was limited to >20 0 by the energy loss of the recoil protons. The experiment was performed at the PM1 beam line at SIN. A beam intensity of about 10 8 particles s -1 was used. (Auth.)
Elastic and inelastic scattering of 180 MeV π+- on 24Mg
International Nuclear Information System (INIS)
Gmitro, M.; Kvasil, J.; Mach, R.
1982-01-01
Equations of the coupled channel method written in the momentum space are solved for the scattering of 180 MeV pions on 24 Mg. The elastic and inelastic differential cross sections are calculated by using the nuclear ground-state- and transition-densities, which describe correctly the (e, e') data for the same nuclear states. The results agree well with the recent (π, π') data [ru