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.
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.
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.
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
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
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)
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.
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
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)
Observation of elastic neutrino-proton scattering
International Nuclear Information System (INIS)
Cline, D.; Entenberg, A.; Kozanecki, W.; Mann, A.K.; Reeder, D.D.; Rubbia, C.; Strait, J.; Sulak, L.; Williams, H.H.
1976-01-01
We have observed thirty events of the process νp→νp with a background expectations of seven events. The neutral-current to charged-current ratio sigma (νp→νp)/sigma (νn→μ - p) is measured to be 0.17 +- 0.05 for 0.3 2 2 where -q 2 is the square of the four-momentum transfer to the proton
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.)
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
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
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
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
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.)
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
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
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.)
The EDDA experiment: proton-proton elastic scattering excitation functions at intermediate energies
International Nuclear Information System (INIS)
Hinterberher, F.
1996-01-01
The EDDA experiment is designed to provide a high precision measurement of proton-proton elastic scattering excitation functions ranging from 0.5 to 2.5 GeV of (lab) incident kinetic energy. It is an internal target experiment utilizing the proton beam of the cooler synchrotron COSY operated by KFA Juelich. The excitation functions are measured during the acceleration ramp of COSY. (author)
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.
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
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.
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)
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
Antiproton-proton and proton-proton elastic scattering at 100 and 200 GeV/c
International Nuclear Information System (INIS)
Kaplan, D.H.; Karchin, P.; Orear, J.; Kalbach, R.M.; Krueger, K.W.; Pifer, A.E.; Baker, W.F.; Eartly, D.P.; Klinger, J.S.; Lennox, A.J.; Rubinstein, R.; McHugh, S.F.
1982-01-01
Antiproton-proton elastic scattering has been measured at 100 GeV/c for 0.5 2 and at 200 GeV/c for 0.9 2 . The data show that the -tapprox. =1.4 (GeV/c) 2 dip recently observed at 50 GeV/c persists to higher incident momenta. Proton-proton measurements made at the same beam momenta show similar structure
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 description of high energy antiproton (proton)-proton elastic scattering
International Nuclear Information System (INIS)
Barshay, S.; Technion-Israel Inst. of Tech., Haifa. Dept. of Physics); Goldberg, J.
1987-01-01
We develop a generalization of the geometric picture for high-energy antiproton (proton)-proton elastic scattering. The eikonal at each impact parameter is considered to have fluctuations about an average value, and is thus characterized by a distribution. A connection to parton branching is made through the specific form of the distribution function for the eikonal. A unified physical theory with significant fluctuations accurately describes the anti p(p)-p data at both √s = 546 GeV and 53 GeV. The fluctuation parameter is remarkably well given by that directly observed in multiparticle production. (orig.)
New description of high energy antiproton (proton)-proton elastic scattering
Energy Technology Data Exchange (ETDEWEB)
Barshay, S; Goldberg, J
1987-10-15
We develop a generalization of the geometric picture for high-energy antiproton (proton)-proton elastic scattering. The eikonal at each impact parameter is considered to have fluctuations about an average value, and is thus characterized by a distribution. A connection to parton branching is made through the specific form of the distribution function for the eikonal. A unified physical theory with significant fluctuations accurately describes the anti p(p)-p data at both ..sqrt..s = 546 GeV and 53 GeV. The fluctuation parameter is remarkably well given by that directly observed in multiparticle production.
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
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).
Measuring the Weak Charge of the Proton via Elastic Electron-Proton Scattering
Energy Technology Data Exchange (ETDEWEB)
Jones, Donald C. [Univ. of Virginia, Charlottesville, VA (United States)
2015-10-01
The Qweak experiment which ran in Hall C at Jefferson Lab in Newport News, VA, and completed data taking in May 2012, measured the weak charge of the proton Q^{p}_{W} via elastic electron-proton scattering. Longitudinally polarized electrons were scattered from an unpolarized liquid hydrogen target. The helicity of the electron beam was flipped at approximately 1 kHz between left and right spin states. The Standard Model predicts a small parity-violating asymmetry of scattering rates between right and left helicity states due to the weak interaction. An initial result using 4% of the data was published in October 2013 [1] with a measured parity-violating asymmetry of -279 ± 35(stat) ± 31 (syst) ppb. This asymmetry, along with other data from parity-violating electron scattering experiments, provided the world's first determination of the weak charge of the proton. The weak charge of the proton was found to be ^{p}_{W} = 0.064 ± 0.012, in good agreement with the Standard Model prediction of ^{p}_{W}(SM) = 0.0708 ± 0.0003[2].
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.
Hinterberger, F; Altmeier, M; Bauer, F; Bisplinghoff, J; Büsser, K; Busch, M; Colberg, T; Diehl, O; Dohrmann, F; Engelhardt, H P; Eversheim, P D; Felden, O; Gebel, R; Glende, M; Greiff, J; Gross-Hardt, R; Hinterberger, F; Jahn, R; Jonas, E; Krause, H; Langkau, R; Lindemann, T; Lindlein, J; Maier, R; Maschuw, R; Mayer-Kuckuk, T; Meinerzhagen, A; Naehle, O; Prasuhn, D; Rohdjess, H; Rosendaal, D; Von Rossen, P; Schirm, N; Schulz-Rojahn, M; Schwarz, V; Scobel, W; Trelle, H J; Weise, E; Wellinghausen, A; Woller, K; Ziegler, R
2000-01-01
The EDDA experiment at the cooler synchrotron COSY measures proton-proton elastic scattering excitation functions in the momentum range 0.8 - 3.4 GeV/c. In phase 1 of the experiment, spin-averaged differential cross sections were measured continuously during acceleration with an internal polypropylene (CH sub 2) fiber target, taking particular care to monitor luminosity as a function of beam momentum. In phase 2, excitation functions of the analyzing power A sub N and the polarization correlation parameters A sub N sub N , A sub S sub S and A sub S sub L are measured using a polarized proton beam and a polarized atomic hydrogen beam target. The paper presents recent d sigma/d OMEGA and A sub N data. The results provide excitation functions and angular distributions of high precision and internal consistency. No evidence for narrow structures was found. The data are compared to recent phase shift solutions.
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
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
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...
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
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.
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
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
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
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
Results from EDDA at COSY: Spin Observables in Proton-Proton Elastic Scattering
International Nuclear Information System (INIS)
Rohdjess, Heiko
2003-01-01
Elastic proton-proton scattering as one of the fundamental hadronic reactions has been studied with the internal target experiment EDDA at the Cooler-Synchrotron COSY/Juelich. A precise measurement of differential cross section, analyzing power and three spin-correlation parameters over a large angular (θc.m. ≅ 35 deg. - 90 deg.) and energy (Tp ≅ 0.5 - 2.5 GeV) range has been carried out in the past years. By taking scattering data during the acceleration of the COSY beam, excitation functions were measured in small energy steps and consistent normalization with respect to luminosity and polarization. The experiment uses internal fiber targets and a polarized hydrogen atomic-beam target in conjunction with a double-layered, cylindrical scintillator hodoscope for particle detection. The results on differential cross sections and analyzing powers have been published and helped to improve phase shift solutions. Recently data taking with polarized beam and target has been completed. Preliminary results for the spin-correlation parameters A NN, ASS, and ASL are presented. The observable ASS has been measured the first time above 800 MeV and our results are in sharp contrast to phase-shift predictions at higher energies. Our analysis shows that some of the ambiguities in the direct reconstruction of scattering amplitudes which also show up as differences between available phase-shift solutions, will be reduced by these new measurements
Study of the proton-proton elastic scattering at high energies through eikonal models
International Nuclear Information System (INIS)
Martini, Alvaro Favinha
1995-01-01
The proton-proton elastic scattering in the center of mass energy region 23 to 63 GeV is investigated through a multiple diffraction model. As an introduction to the subject, a detailed review of the fundamental basis of the Multiple Diffraction Formalism and a survey of the multiple diffraction models (geometrical) currently used are presented. The goal of this investigation is to reformulate one of these models, which makes use of an elementary (parton-parton) amplitude purely imaginary and is not able to predict the ρ-parameter (the ratio of the forward real and imaginary parts of the hadronic amplitude). Introducing a real part for the elementary amplitude proportional to the imaginary part, improvements in the formalism are obtained. It is shown that this new approach is able to reproduce all experimental data on differential and integrated cross sections (total, elastic and inelastic), but not the ρ-parameter as function of the energy. Then, starting from fitting of this parameter an overall reproduction of the physical observables is obtained, with the exception of the dip region (diffractive minimum in the differential cross section) overall description are also not firmly reached in all these models. Finally, alternatives to improve the results in a future research are suggested and discussed. (author)
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
Nuclear proton-proton elastic scattering via the Trojan Horse method
International Nuclear Information System (INIS)
Tumino, A.; Spitaleri, C.; Mukhamedzhanov, A.
2009-01-01
The Trojan Horse Method (THM) is a powerful indirect technique to study charged particle two-body reactions at sub-Coulomb energies [1,2]. As known, it makes it possible to extract their cross sections down to the relevant energies without experiencing Coulomb suppression. For this reason, since a couple of decades it is successfully applied to rearrangement reactions of astrophysical interest. Recently, we have investigate the suppression of the Coulomb amplitude when the THM is applied to scattering processes. This was done by considering the p - p scattering at low energy, the simplest case where the Coulomb suppression can be observed. Proton-proton cross section was extensively studied in the past. Its energy trend appears to be very similar to that of n-n or p-n systems (1/E behaviour) except at lower proton relative energies, where a deep minimum shows up (E pp = 191.2 keV, θ cm = 90 o ). This minimum is interpreted as being the signature of the interference between nuclear and Coulomb scattering amplitudes. Therefore, if one considers that a non sizable Coulomb amplitude would make the minimum in the p-p cross section to disappear, the strong interference pattern offers an unique possibility to validate the THM suppression of Coulomb amplitude for scattering. This has been realized by measuring the p - p elastic scattering within the region of the minimum through the 2 H (p, pp)n reaction at 4.8 and 5 MeV in the quasi-free (QF) kinematics regime [3,4]. The THM p-p cross-section was extracted in the framework of the Plane Wave Impulse Approximation [5] down to E lab = 80 keV, and compared with the direct p-p behaviour. No minimum shows up in the THM data, whose trend appears to be smooth, much similar to that of the n-n or n-p cross-section. A detailed formalism was developed to build-up the expression of the theoretical half-off-shell p-p cross section, whose behaviour agrees with the THM data, given the fact that in its expression the Coulomb amplitude is
Proton-proton elastic scattering at the LHC energy of $\\sqrt{s}$ = 7 TeV
Antchev, G.; Aspell, P.; Atanassov, I.; Avati, V.; Baechler, J.; Berardi, V.; Berretti, M.; Bozzo, M.; Brucken, E.; Buzzo, A.; Cafagna, F.S.; Calicchio, M.; Catanesi, M.G.; Covault, C.; Csanad, M.
2011-01-01
Proton-proton elastic scattering has been measured by the TOTEM experiment at the CERN Large Hadron Collider at √ s = 7 TeV in dedicated runs with the Roman Pot detectors placed as close as seven times the transverse beam size (σbeam) from the outgoing beams. After careful study of the accelerator optics and the detector alignment, |t| , the square of four-momentum transferred in the elastic scattering process, has been determined with an uncertainty of δ t = 0.1 GeV √ |t|. In this letter the...
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)
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)
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 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
Study of elastic scattering of polarized proton with 6He by folding model
International Nuclear Information System (INIS)
Iseri, Y.; Tanifuji, M.; Ishikawa, S.; Hiyama, E.; Yamamoto, Y.
2005-01-01
Experimental data of the elastic scattering of 6 He with polarized proton target has been analyzed using a simple folding model. As we regard 6 He as three bodies consisting of 4 He+n+n, the potential between the proton and 6 He is obtained by folding the two potentials, one between a proton and 4 He and another between a proton and a neutron, with the density distribution of 6 He. Calculated results of both the differential cross section and the vector analyzing power reproduce the experimental data satisfactorily. It is shown that the vector analyzing power of the p- 6 He scattering is mainly due to the spin orbit interaction between the proton and 4 He. (S. Funahashi)
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
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
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
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.)
Large Logarithms in the Beam Normal Spin Asymmetry of Elastic Electron--Proton Scattering
Energy Technology Data Exchange (ETDEWEB)
Andrei Afanasev; Mykola Merenkov
2004-06-01
We study a parity-conserving single-spin beam asymmetry of elastic electron-proton scattering induced by an absorptive part of the two-photon exchange amplitude. It is demonstrated that excitation of inelastic hadronic intermediate states by the consecutive exchange of two photons leads to logarithmic and double-logarithmic enhancement due to contributions of hard collinear quasi-real photons. The asymmetry at small electron scattering angles is expressed in terms of the total photoproduction cross section on the proton, and is predicted to reach the magnitude of 20-30 parts per million. At these conditions and fixed 4-momentum transfers, the asymmetry is rising logarithmically with increasing electron beam energy, following the high-energy diffractive behavior of total photoproduction cross section on the proton.
Elastic and inelastic scattering of 2 to 10 MeV protons by lithium isotopes
International Nuclear Information System (INIS)
Laurat, M.
1969-01-01
A description is given of the experimental set-up which has been devised for carrying out spectrometric and absolute cross-section measurements on the reactions induced by protons accelerated in a 12 MeV Van de Graaff Tandem. The particles are detected by silicon junctions; the weight of the targets (about ten μg/cm 2 ) is determined by the quartz method. The experimental equipment has been controlled by a study of proton scattering by lithium-6, and has made it possible to evaluate the elastic and inelastic scattering (1. level excitation) by lithium 7 of 2 to 9 MeV protons. The most probable spin and parity values for the six levels of 8 Be between 19 and 25 MeV excitation energy have been determined from a knowledge of the observed structure. (author) [fr
Hasell, D. K.; OLYMPUS Collaboration
2018-02-01
The OLYMPUS collaboration has recently made a precise measurement of the positron-proton to electron-proton elastic scattering cross section ratio, R 2γ, over a wide range of the virtual photon polarization, 0.456 reasonable agreement with predictions based on phenomenological fits to the available form factor data. The motivation for measuring R 2γ will be presented followed by a description of the OLYMPUS experiment. The importance of radiative corrections in the analysis will be shown also. Then we will present the OLYMPUS results and compare with results from two similar experiments and theoretical calculations.
Analyzing power for proton elastic scattering from the neutron-rich 6He nucleus
International Nuclear Information System (INIS)
Uesaka, T.; Sakaguchi, S.; Kawabata, T.; Sasamoto, Y.; Iseri, Y.; Amos, K.; Aoi, N.; Hiyama, E.; Sekiguchi, K.; Yamaguchi, M.; Hashimoto, Y.; Satou, Y.; Shinohara, M.; Ichikawa, M.; Itoh, M.; Matsuo, R.; Wakui, T.; Ichikawa, Y.; Iwasaki, H.; Kuboki, H.
2010-01-01
Vector analyzing power for the proton- 6 He elastic scattering at 71 MeV/nucleon has been measured for the first time, with a newly developed polarized proton solid target, which works at a low magnetic field of 0.09 T. The results are found to be incompatible with a t-matrix folding model prediction. Comparisons of the data with g-matrix folding analyses clearly show that the vector analyzing power is sensitive to the nuclear structure model used in the reaction analysis. The α-core distribution in 6 He is suggested to be a possible key for understanding the nuclear structure sensitivity.
Energy Technology Data Exchange (ETDEWEB)
Henderson, B.S. [Massachusetts Institute of Technology, Cambridge, MA (United States); Ice, L.D. [Arizona State Univ., Tempe, AZ (United States); Khaneft, D. [Mainz Univ. (Germany); Collaboration: OLYMPUS Collaboration; and others
2016-12-15
The OLYMPUS collaboration reports on a precision measurement of the positron-proton to electron-proton elastic cross section ratio, R{sub 2γ}, a direct measure of the contribution of hard two- photon exchange to the elastic cross section. In the OLYMPUS measurement, 2.01 GeV electron and positron beams were directed through a hydrogen gas target internal to the DORIS storage ring at DESY. A toroidal magnetic spectrometer instrumented with drift chambers and time-of-flight scintillators detected elastically scattered leptons in coincidence with recoiling protons over a scattering angle range of ∼20 to 80 . The relative luminosity between the two beam species was monitored using tracking telescopes of interleaved GEM and MWPC detectors at 12 , as well as symmetric Moeller/Bhabha calorimeters at 1.29 . A total integrated luminosity of 4.5 fb{sup -1} was collected. In the extraction of R{sub 2γ}, radiative effects were taken into account using a Monte Carlo generator to simulate the convolutions of internal bremsstrahlung with experiment-specific conditions such as detector acceptance and reconstruction efficiency. The resulting values of R{sub 2γ}, presented here for a wide range of virtual photon polarization 0.456<ε<0.978, are smaller than some hadronic two-photon exchange calculations predict, but are in reasonable agreement with a subtracted dispersion model and a phenomenological fit to the form factor data.
Henderson, B. S.; Ice, L. D.; Khaneft, D.; O'Connor, C.; Russell, R.; Schmidt, A.; Bernauer, J. C.; Kohl, M.; Akopov, N.; Alarcon, R.; Ates, O.; Avetisyan, A.; Beck, R.; Belostotski, S.; Bessuille, J.; Brinker, F.; Calarco, J. R.; Carassiti, V.; Cisbani, E.; Ciullo, G.; Contalbrigo, M.; de Leo, R.; Diefenbach, J.; Donnelly, T. W.; Dow, K.; Elbakian, G.; Eversheim, P. D.; Frullani, S.; Funke, Ch.; Gavrilov, G.; Gläser, B.; Görrissen, N.; Hasell, D. K.; Hauschildt, J.; Hoffmeister, Ph.; Holler, Y.; Ihloff, E.; Izotov, A.; Kaiser, R.; Karyan, G.; Kelsey, J.; Kiselev, A.; Klassen, P.; Krivshich, A.; Lehmann, I.; Lenisa, P.; Lenz, D.; Lumsden, S.; Ma, Y.; Maas, F.; Marukyan, H.; Miklukho, O.; Milner, R. G.; Movsisyan, A.; Murray, M.; Naryshkin, Y.; Perez Benito, R.; Perrino, R.; Redwine, R. P.; Rodríguez Piñeiro, D.; Rosner, G.; Schneekloth, U.; Seitz, B.; Statera, M.; Thiel, A.; Vardanyan, H.; Veretennikov, D.; Vidal, C.; Winnebeck, A.; Yeganov, V.; Olympus Collaboration
2017-03-01
The OLYMPUS Collaboration reports on a precision measurement of the positron-proton to electron-proton elastic cross section ratio, R2 γ , a direct measure of the contribution of hard two-photon exchange to the elastic cross section. In the OLYMPUS measurement, 2.01 GeV electron and positron beams were directed through a hydrogen gas target internal to the DORIS storage ring at DESY. A toroidal magnetic spectrometer instrumented with drift chambers and time-of-flight scintillators detected elastically scattered leptons in coincidence with recoiling protons over a scattering angle range of ≈20 ° to 80°. The relative luminosity between the two beam species was monitored using tracking telescopes of interleaved gas electron multiplier and multiwire proportional chamber detectors at 12°, as well as symmetric Møller or Bhabha calorimeters at 1.29°. A total integrated luminosity of 4.5 fb-1 was collected. In the extraction of R2 γ, radiative effects were taken into account using a Monte Carlo generator to simulate the convolutions of internal bremsstrahlung with experiment-specific conditions such as detector acceptance and reconstruction efficiency. The resulting values of R2 γ, presented here for a wide range of virtual photon polarization 0.456 <ɛ <0.978 , are smaller than some hadronic two-photon exchange calculations predict, but are in reasonable agreement with a subtracted dispersion model and a phenomenological fit to the form factor data.
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
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.
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
Angular distribution of elastic scattering of 17F and 18Ne on proton
International Nuclear Information System (INIS)
Lu Zhaohui; Wu Heyu; Hu Rongjiang; Zhu Yongtai; Zhang Baoguo; Li Zuyu; Wei Zhiyong; Duan Liming; Wang Hongwei; Xiao Zhigang; Wang Sufang; Jin Genming; Guo Zhongyan; Xiao Guoqing; Zhu Haidong; Liu Yongying; Chen Keliang; Chen Tao; Li Xiangqing; Li Zhihuan
2002-01-01
Under reverse kinematics, elastic scattering of 17 F and 18 Ne on proton is studied. The experimental differential cross sections were measured. A kind of global optical potential with the CH89 parameters is used to describe the radioactive nucleus as an initial optical potential parameters. The experimental differential cross section data are analyzed by using the theoretical calculation code DWUCK4 with the distorted-wave Born approximation and parameter search subroutine ABOD which automatically searches the suitable parameters. Then the optical potential parameters of scattering 17 F and 18 Ne on proton are obtained. From the analyses of the optimized parameters, the real central potential mean-square radii of 17 F and 18 Ne, 3.239 fm and 3.317 fm are deduced, respectively
Elastic scattering of polarized protons on helium three at 800 MeV
Energy Technology Data Exchange (ETDEWEB)
Azizi, A.
1985-07-01
A set of spin dependent parameters and cross sections has been measured for polarized p-/sup 3/He elastic scattering over the range of q .7 to 4.2 fm/sup -1/. The experiment was done at the Los Alamos Meson Physics Facility (LAMPF) using the High Resolution Spectrometer (HRS) with a polarized proton beam at .8 GeV. The focal plane polarimeter of the HRS was used to determine the spin direction of the scattered proton. Since /sup 3/He is one of the simplest nuclei, polarized p-/sup 3/He scattering provides a very sensitive test of multiple scattering theories. The theoretical analysis was done by using two different wave functions for /sup 3/He as input to the multiple scattering theory. The theoretical calculations and experimental data together will give us useful information about nucleon-nucleon amplitudes and also help us to obtain a better understanding of the scattering process. 68 refs., 55 figs., 9 tabs.
Proton-proton elastic scattering from 150 to 515 MeV
International Nuclear Information System (INIS)
Bugg, D.V.; Edginton, J.A.; Amsler, C.
1977-12-01
The parameters D, R, R' and P for pp elastic scattering have been measured in the centre of mass angular range 13 to 58 0 with an accuracy of about +- 0.02 at 209, 324, 379, 425 and 515 MeV. These results are incorporated with earlier data into a phase shift analysis. Phase shifts are generally in agreement with theoretical predictions of the Paris group, although the F wave spin-orbit combination is rather stronger than predicted. The fitted value for the π 0 p anti p coupling constant is g 0 2 = 14.06 +- 0.65. (author)
Optical model analysis for 30MeV polarized proton elastic scattering
International Nuclear Information System (INIS)
Pham, D.-L.; Swiniarski, R. de.
1977-05-01
The proton elastic scattering cross sections and analyzing powers at 30MeV have been used to derive optical model parameters for ten elements from 10 B to 32 S. A set of average geometrical parameters (rsub(o)=1.10fm, rsub(LS)=1.0fm and asub(I)=0.60fm) is found to give good fits to the entire data, the other geometrical parameters being rsub(I)=(1.35+-0.15)fm, asub(o)=(0.75+-0.10)fm and asub(LS)=(0.35+-0.07)fm. The dynamical parameters with fixed geometry are presented
Helicity in proton–proton elastic scattering and the spin structure of the pomeron
Directory of Open Access Journals (Sweden)
Carlo Ewerz
2016-12-01
Full Text Available We discuss different models for the spin structure of the nonperturbative pomeron: scalar, vector, and rank-2 symmetric tensor. The ratio of single-helicity-flip to helicity-conserving amplitudes in polarised high-energy proton–proton elastic scattering, known as the complex r5 parameter, is calculated for these models. We compare our results to experimental data from the STAR experiment. We show that the spin-0 (scalar pomeron model is clearly excluded by the data, while the vector pomeron is inconsistent with the rules of quantum field theory. The tensor pomeron is found to be perfectly consistent with the STAR data.
Proton nucleus elastic scattering at 800 MeV: the role of intermediate isobars
International Nuclear Information System (INIS)
Auger, J.P.; Maillet, J.P.; Lazard, C.; Lombard, R.J.
1984-10-01
Proton nucleus elastic scattering at 800 MeV has been calculated in the Glauber model for 16 O, 40 Ca, 48 Ca and 208 Pb. Nuclear densities are taken from Hartree-Fock-BCS calculations. For the nucleon-nucleon amplitudes, use is made of two recent phase shift analysis. The effects of intermediate isobars are included by means of a simple model. The results show that the experimental data are qualitatively understood. The polarization turns out to be quite sensitive to the intermediate isobar effects, which consequently need to be calculated more carefully
A fully microscopic model of 200 MeV proton-12C elastic and inelastic scattering
International Nuclear Information System (INIS)
Karataglidis, S.; Dortmans, P.J.; Amos, K.; de Swiniarski, R.
1996-01-01
An effective two nucleon (NN) interaction in the nuclear medium is defined from an accurate mapping of the NN g matrices obtained by solving the Brueckner-Bethe-Goldstone equations for infinite nuclear matter. That effective interaction is used in a fully microscopic calculation of the nonlocal effective proton- 12 C interaction from which are obtained predictions of the differential cross section and analysing power for 200 MeV elastic scattering. The relative motion wave functions so found are used as the distorted waves in a distorted wave approximation (DWA) study of select inelastic scattering events. The effective NN interaction is used as the transition operator in those calculations. The relevant nuclear spectroscopy for the elastic and DWA (p, p') calculations is found from a full (0 + 2) ℎω shell model evaluation of the positive parity states while a restricted (1 + 3)ℎω has been used to give the negative parity states. Results are compared with those of the 0p-shell model of Cohen and Kurath or with those based upon axially symmetric, projected Hartree-Fock calculations. The diverse structure model wave functions are assessed by using them in calculations to compare with measured longitudinal, transverse electric and transverse magnetic form factors from electron scattering to many of the excited states of 12 C. Using those models of the structure of 12 C in the completely microscopic model of the elastic and inelastic scattering of 200 MeV protons, good fits have been found to the cross section and analysing power data. 50 refs., 3 tabs., 20 figs
Korolev, G. A.; Dobrovolsky, A. V.; Inglessi, A. G.; Alkhazov, G. D.; Egelhof, P.; Estradé, A.; Dillmann, I.; Farinon, F.; Geissel, H.; Ilieva, S.; Ke, Y.; Khanzadeev, A. V.; Kiselev, O. A.; Kurcewicz, J.; Le, X. C.; Litvinov, Yu. A.; Petrov, G. E.; Prochazka, A.; Scheidenberger, C.; Sergeev, L. O.; Simon, H.; Takechi, M.; Tang, S.; Volkov, V.; Vorobyov, A. A.; Weick, H.; Yatsoura, V. I.
2018-05-01
The absolute differential cross section for small-angle proton elastic scattering on the proton-rich 8B nucleus has been measured in inverse kinematics for the first time. The experiment was performed using a secondary radioactive beam with an energy of 0.7 GeV/u at GSI, Darmstadt. The active target, namely hydrogen-filled time projection ionization chamber IKAR, was used to measure the energy, angle and vertex point of the recoil protons. The scattering angle of the projectiles was simultaneously determined by the tracking detectors. The measured differential cross section is analyzed on the basis of the Glauber multiple scattering theory using phenomenological nuclear-density distributions with two free parameters. The radial density distribution deduced for 8B exhibits a halo structure with the root-mean-square (rms) matter radius Rm = 2.58 (6) fm and the rms halo radius Rh = 4.24 (25) fm. The results on 8B are compared to those on the mirror nucleus 8Li investigated earlier by the same method. A comparison is also made with previous experimental results and theoretical predictions for both nuclei.
Quantal inversion of cross-section for the elastic scattering of 200 MeV protons from 12C
International Nuclear Information System (INIS)
Allen, L.J.; Amos, K.; Dortmans, P.J.
1994-01-01
Fixed energy quantal inverse scattering theory has been used to analyse the differential cross-section from the elastic scattering of 200 MeV protons from 12 C. Ambiguities in obtaining the scattering function from the differential cross-section are discussed and by means of example it is illustrated that not all scattering functions lead to physically reasonable potentials. 8 refs., 2 tabs., 4 figs
International Nuclear Information System (INIS)
Gaidot, A.; Bruneton, C.; Bystricky, J.; Cozzika, G.; Deregel, J.; Ducros, Y.; Khantine-Langlois, F.; Lehar, F.; Lesquen, A. de; Merlo, J.P.; Miyashita, S.; Movchet, J.; Pierrard, J.; Raoul, J.C.; Van Rossum, L.; Kanavets, V.P.
1975-01-01
The polarization parameter P has been measured for elastic scattering on polarized protons, of π - , K - and anti-p at 40GeV/c and of π + , K + and p at 45GeV/c. Four-momentum transfer ranges from -0.08 to -1.8(GeV/c) 2 for π - p and pp, and from -0.08 to -1.2(GeV/c) 2 for π + , K + or K - and anti-p [fr
Tensor analyzing powers in deuteron--proton elastic scattering and the breakup reaction at 45.4 MeV
International Nuclear Information System (INIS)
Conzett, H.E.
1978-08-01
Recently the tensor analyzing powers in vector d + p elastic scattering and in the breakup reaction at E/sub d/ = 45.4 MeV were measured. The elastic results now establish a rather complete set of polarization data in nucleon--deuteron scattering at E/sub N/ = 22.7 MeV, which consists of the proton analyzing power, the deuteron vector and tensor analyzing powers, and vector polarization transfer measurements, as well. 8 references
Proton-Nucleus Elastic Cross Sections Using Two-Body In-Medium Scattering Amplitudes
Tripathi, R. K.; Wilson, John W.; Cucinotta, Francis A.
2001-01-01
Recently, a method was developed of extracting nucleon-nucleon (NN) cross sections in the medium directly from experiment. The in-medium NN cross sections form the basic ingredients of several heavy-ion scattering approaches including the coupled-channel approach developed at the Langley Research Center. The ratio of the real to the imaginary part of the two-body scattering amplitude in the medium was investigated. These ratios are used in combination with the in-medium NN cross sections to calculate elastic proton-nucleus cross sections. The agreement is excellent with the available experimental data. These cross sections are needed for the radiation risk assessment of space missions.
New results for antiproton-proton elastic scattering and various theoretical models
International Nuclear Information System (INIS)
Fazal-e-Aleem; Saleem, M.; Yodh, G.B.
1991-01-01
The most recent measurements of the ratio ρ of the real and imaginary parts of the forward-scattering amplitudes at 0.546 TeV, the total and elastic differential cross sections at 0.546 and 1.8 TeV for proton-antiproton scattering, are compared to the predictions of the generalized Chou-Yang and other theoretical models. For 1.8 TeV, the presence or absence of the break near -t∼0.15 (GeV/c) 2 and of the dip in the vicinity of 0.6 (GeV/c) 2 are also discussed in the light of various predictions. The possibility of a further rise of the ratio ρ at 1.8 TeV is also probed
Proton-proton elastic scattering at the LHC energy of $\\sqrt{s}$ = 7 TeV
INSPIRE-00062364; Aspell, P.; Atanassov, I.; Avati, V.; Baechler, J.; Berardi, V.; Berretti, M.; Bozzo, M.; Brucken, E.; Buzzo, A.; Cafagna, F.S.; Calicchio, M.; Catanesi, M.G.; Covault, C.; Csanad, M.; Csorgo, T.; Deile, M.; Dimovasili, E.; Doubek, M.; Eggert, K.; Eremin, V.; Ferro, F.; Fiergolski, A.; Garcia, F.; Giani, S.; Greco, V.; Grzanka, L.; Heino, J.; Hilden, T.; Janda, M.; Kaspar, J.; Kopal, J.; Kundrat, V.; Kurvinen, K.; Lami, S.; Latino, G.; Lauhakangas, R.; Leszko, T.; Lippmaa, E.; Lokajicek, M.; Lo Vetere, M.; Lucas Rodriguez, F.; Macri, M.; Magaletti, L.; Magazzu, G.; Mercadante, A.; Minutoli, S.; Nemes, F.; Niewiadomski, H.; Noschis, E.; Novak, T.; Oliveri, E.; Oljemark, F.; Orava, R.; Oriunno, M.; Osterberg, K.; Perrot, A.L.; Palazzi, P.; Pedreschi, E.; Petajajarvi, J.; Prochazka, J.; Quinto, M.; Radermacher, E.; Radicioni, E.; Ravotti, F.; Robutti, E.; Ropelewski, L.; Ruggiero, G.; Saarikko, H.; Santroni, A.; Scribano, A.; Sette, G.; Snoeys, W.; Spinella, F.; Sziklai, J.; Taylor, C.; Turini, N.; Vacek, V.; Vitek, M.; Welti, J.; Whitmore, J.
2011-01-01
Proton-proton elastic scattering has been measured by the TOTEM experiment at the CERN Large Hadron Collider at √ s = 7 TeV in dedicated runs with the Roman Pot detectors placed as close as seven times the transverse beam size (σbeam) from the outgoing beams. After careful study of the accelerator optics and the detector alignment, |t| , the square of four-momentum transferred in the elastic scattering process, has been determined with an uncertainty of δ t = 0.1 GeV √ |t|. In this letter the first results of the differential cross section are presented covering a |t|-range from 0.36 to 2.5 GeV**2. The differential cross-section in the range 0.36 < |t| < 0.47 GeV**2 is described by an exponential with a slope parameter B = (23.6±0.5stat ±0.4syst)GeV**−2, followed by a significant diffractive minimum at |t| = (0.53±0.01stat±0.01syst)GeV**2. For |t|-values larger than ∼ 1:5GeV**2, the cross-section exhibits a power law behaviour with an exponent of -7.8 ± 0.3stat ±0.1syst. When compared to...
Recoil-proton polarization in πp elastic scattering at 547 and 625 MeV/c
International Nuclear Information System (INIS)
Seftor, C.J.; Adrian, S.D.; Briscoe, W.J.; Mokhtari, A.; Taragin, M.F.; Sadler, M.E.; Barlow, D.B.; Nefkens, B.M.K.; Pillai, C.
1989-01-01
The polarization of the recoil proton in π + p and π - p elastic scattering using a liquid-hydrogen target has been measured for backward angles at 547 and 625 MeV/c. The scattered pion and recoil proton were detected in coincidence using the large-acceptance spectrometer to detect and analyze the momentum of the pions and the JANUS polarimeter to identify and measure the polarization of the protons. Results from this experiment agree with other measurements of the recoil polarization, with analyzing-power data previously taken by this group, and with predictions of partial-wave analyses
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.
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.
Energy Technology Data Exchange (ETDEWEB)
Martini, Alvaro Favinha
1995-12-31
The proton-proton elastic scattering in the center of mass energy region 23 to 63 GeV is investigated through a multiple diffraction model. As an introduction to the subject, a detailed review of the fundamental basis of the Multiple Diffraction Formalism and a survey of the multiple diffraction models (geometrical) currently used are presented. The goal of this investigation is to reformulate one of these models, which makes use of an elementary (parton-parton) amplitude purely imaginary and is not able to predict the {rho}-parameter (the ratio of the forward real and imaginary parts of the hadronic amplitude). Introducing a real part for the elementary amplitude proportional to the imaginary part, improvements in the formalism are obtained. It is shown that this new approach is able to reproduce all experimental data on differential and integrated cross sections (total, elastic and inelastic), but not the {rho}-parameter as function of the energy. Then, starting from fitting of this parameter an overall reproduction of the physical observables is obtained, with the exception of the dip region (diffractive minimum in the differential cross section) overall description are also not firmly reached in all these models. Finally, alternatives to improve the results in a future research are suggested and discussed. (author) 69 refs., 69 figs., 20 tabs.
Measurement of proton-proton elastic scattering and total cross-section at $\\sqrt{s}$ = 7 TeV
Antchev, G; Atanassov, I; Avati, V; Baechler, J; Berardi, V; Berretti, M; Bossini, E; Bozzo, M; Brogi, P; Brucken, E; Buzzo, A; Cafagna, F S; Calicchio, M; Catanesi, M G; Covault, C.; Csanad, M.; Csorgo, T.; Deile, M.; Eggert, K.; Eremin, V.; Ferretti, R.; Ferro, F.; Fiergolski, A.; Garcia, F.; Giani, S.; Greco, V.; Grzanka, L.; Heino, J.; Hilden, T.; Intonti, R.A.; Kaspar, J.; Kopal, J.; Kundrat, V.; Kurvinen, K.; Lami, S.; Latino, G.; Lauhakangas, R.; Leszko, T.; Lippmaa, E.; Lokajıcek, M.; Lo Vetere, M.; Macrı, M.; Maki, T.; Mercadante, A.; Minafra, N.; Minutoli, S.; Nemes, F.; Niewiadomski, H.; Oliveri, E.; Oljemark, F.; Orava, R.; Oriunno, M.; Osterberg, K.; Palazzi, P.; Prochazka, J.; Quinto, M.; Radermacher, E.; Radicioni, E.; Ravotti, F.; Robutti, E.; Rodrıguez, F.L.; Ropelewski, L.; Ruggiero, G.; Saarikko, H.; Santroni, A.; Scribano, A.; Smajek, J.; Snoeys, W.; Sziklai, J.; Taylor, C.; Turini, N.; Vacek, V.; Vıtek, M.; Welti, J.; Whitmore, J.
2013-01-01
At the LHC energy of $\\sqrt{s}$ = 7 TeV, under various beam and background conditions, luminosities, and Roman Pot positions, TOTEM has measured the differential cross-section for proton-proton elastic scattering as a function of the four-momentum transfer squared t. The results of the different analyses are in excellent agreement demonstrating no sizeable dependence on the beam conditions. Due to the very close approach of the Roman Pot detectors to the beam center ( around 5 $\\sigma$ beam) in a dedicated run with $\\beta$* = 90m, abs(t)-values down to 5 10**-3 GeV**2 were reached. The exponential slope of the differential elastic cross-section in this newly explored abs(t)-region remained unchanged and thus an exponential fit with only one constant B = (19.90+/-0.3)GeV-2 over the large abs(t)-range from 0.005 to 0.2GeV**2 describes the differential distribution well. The high precision of the measurement and the large fit range lead to an error on the slope parameter B which is remarkably small compared to p...
A new version of PIRK (elastic pion-nucleus scattering) to handle differing proton and neutron radii
International Nuclear Information System (INIS)
Funsten, H.O.
1979-01-01
This program is a modification of the Eisenstein-Miller program (1974) for calculating elastic pion-nucleus differential cross sections using free π-N scattering amplitudes. This revision permits the use of separate proton and neutron radii for the nuclear density function rho(r). (Auth.)
Proton-proton elastic scattering at the LHC energy of \\chem{\\sqrt{s} = 7\\,TeV}
TOTEM Collaboration; Antchev, G.; Aspell, P.; Atanassov, I.; Avati, V.; Baechler, J.; Berardi, V.; Berretti, M.; Bozzo, M.; Brücken, E.; Buzzo, A.; Cafagna, F. S.; Calicchio, M.; Catanesi, M. G.; Covault, C.; Csanád, M.; Csörgö, T.; Deile, M.; Dimovasili, E.; Doubek, M.; Eggert, K.; Eremin, V.; Ferro, F.; Fiergolski, A.; Garcia, F.; Giani, S.; Greco, V.; Grzanka, L.; Heino, J.; Hilden, T.; Janda, M.; Kašpar, J.; Kopal, J.; Kundrát, V.; Kurvinen, K.; Lami, S.; Latino, G.; Lauhakangas, R.; Leszko, T.; Lippmaa, E.; Lokajíček, M.; Lo Vetere, M.; Rodríguez, F. Lucas; Macrí, M.; Magaletti, L.; Magazzù, G.; Mercadante, A.; Minutoli, S.; Nemes, F.; Niewiadomski, H.; Noschis, E.; Novák, T.; Oliveri, E.; Oljemark, F.; Orava, R.; Oriunno, M.; Österberg, K.; Perrot, A.-L.; Palazzi, P.; Pedreschi, E.; Petäjäjärvi, J.; Procházka, J.; Quinto, M.; Radermacher, E.; Radicioni, E.; Ravotti, F.; Robutti, E.; Ropelewski, L.; Ruggiero, G.; Saarikko, H.; Santroni, A.; Scribano, A.; Sette, G.; Snoeys, W.; Spinella, F.; Sziklai, J.; Taylor, C.; Turini, N.; Vacek, V.; Vitek, M.; Welti, J.; Whitmore, J.
2011-08-01
Proton-proton elastic scattering has been measured by the TOTEM experiment at the CERN Large Hadron Collider at \\sqrt{s} = 7\\,TeV in dedicated runs with the Roman Pot detectors placed as close as seven times the transverse beam size (σbeam) from the outgoing beams. After careful study of the accelerator optics and the detector alignment, |t|, the square of four-momentum transferred in the elastic scattering process, has been determined with an uncertainty of \\delta t = 0.1\\,\\rm{GeV} \\sqrt{\\vert t\\vert } . In this letter, first results of the differential cross-section are presented covering a |t|-range from 0.36 to 2.5 GeV2. The differential cross-section in the range 0.36 < |t| < 0.47 GeV2 is described by an exponential with a slope parameter B = (23.6 ± 0.5stat ± 0.4syst) GeV-2, followed by a significant diffractive minimum at |t| = (0.53 ± 0.01stat ± 0.01syst) GeV2. For |t|-values larger than ~1.5 GeV2, the cross-section exhibits a power law behaviour with an exponent of -7.8 ± 0.3stat ± 0.1syst. When compared to predictions based on the different available models, the data show a strong discriminative power despite the small t-range covered.
Measurement of small angle antiproton-proton elastic scattering at √s =546 and 1800 GeV
International Nuclear Information System (INIS)
Abe, F.; Albrow, M.; Amidei, D.; Anway-Wiese, C.; Apollinari, G.; Atac, M.; Auchincloss, P.; Azzi, P.; Bacchetta, N.; Baden, A.R.; Badgett, W.; Bailey, M.W.; Bamberger, A.; de Barbaro, P.; Barbaro-Galtieri, A.; Barnes, V.E.; Barnett, B.A.; Bauer, G.; Baumann, T.; Bedeschi, F.; Behrends, S.; Belforte, S.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Benlloch, J.; Bensinger, J.; Beretvas, A.; Berge, J.P.; Bertolucci, S.; Biery, K.; Bhadra, S.; Binkley, M.; Bisello, D.; Blair, R.; Blocker, C.; Bodek, A.; Bolognesi, V.; Booth, A.W.; Boswell, C.; Brandenburg, G.; Brown, D.; Buckley-Geer, E.; Budd, H.S.; Busetto, G.; Byon-Wagner, A.; Byrum, K.L.; Campagnari, C.; Campbell, M.; Caner, A.; Carey, R.; Carithers, W.; Carlsmith, D.; Carroll, J.T.; Cashmore, R.; Castro, A.; Cen, Y.; Cervelli, F.; Chadwick, K.; Chapman, J.; Chapin, T.J.; Chiarelli, G.; Chinowsky, W.; Cihangir, S.; Clark, A.G.; Cobal, M.; Connor, D.; Contreras, M.; Cooper, J.; Cordelli, M.; Crane, D.; Cunningham, J.D.; Day, C.; DeJongh, F.; Dell'Agnello, S.; Dell'Orso, M.; Demortier, L.; Denby, B.; Derwent, P.F.; Devlin, T.; Dickson, M.; Drucker, R.B.; Dunn, A.; Einsweiler, K.; Elias, J.E.; Ely, R.; Eno, S.; Errede, S.; Etchegoyen, A.; Farhat, B.; Frautschi, M.; Feldman, G.J.; Flaugher, B.; Foster, G.W.; Franklin, M.; Freeman, J.; Fuess, T.; Fukui, Y.; Garfinkel, A.F.; Gauthier, A.; Geer, S.; Gerdes, D.W.; Giannetti, P.; Giokaris, N.; Giromini, P.; Gladney, L.; Gold, M.; Gonzalez, J.; Goulianos, K.; Grassmann, H.; Grieco, G.M.; Grindley, R.; Grosso-Pilcher, C.; Haber, C.; Hahn, S.R.; Handler, R.; Hara, K.; Harral, B.; Harris, R.M.; Hauger, S.A.; Hauser, J.; Hawk, C.; Hessing, T.; Hollebeek, R.; Holloway, L.; Hoelscher, A.; Hong, S.; Houk, G.; Hu, P.; Hubbard, B.; Huffman, B.T.; Hughes, R.; Hurst, P.; Huth, J.; Hylen, J.; Incagli, M.; Ino, T.; Iso, H.; Jessop, C.P.; Johnson, R.P.; Joshi, U.; Kadel, R.W.; Kamon, T.; Kanda, S.; Kardelis, D.A.; Karliner, I.; Kearns, E.; Keeble, L.; Kephart, R.; Kesten, P.
1994-01-01
Antiproton-proton elastic scattering was measured at c.m.s. energies √s =546 and 1800 GeV in the range of four-momentum transfer squared 0.025 2 . The data are well described by the exponential form e bt with a slope b=15.28±0.58 (16.98±0.25) GeV -2 at √s =546 (1800) GeV. The elastic scattering cross sections are, respectively, σ el =12.87±0.30 and 19.70±0.85 mb
Henderson, B. S.; Ice, L. D.; Khaneft, D.; O'Connor, C.; Russell, R.; Schmidt, A.; Bernauer, J. C.; Kohl, M.; Akopov, N.; Alarcon, R.; Ates, O.; Avetisyan, A.; Beck, R.; Belostotski, S.; Bessuille, J.
2016-01-01
The OLYMPUS Collaboration reports on a precision measurement of the positron-proton to electron-proton elastic cross section ratio, \\ud R\\ud 2\\ud γ\\ud , a direct measure of the contribution of hard two-photon exchange to the elastic cross section. In the OLYMPUS measurement, 2.01 GeV electron and positron beams were directed through a hydrogen gas target internal to the DORIS storage ring at DESY. A toroidal magnetic spectrometer instrumented with drift chambers and time-of-flight scintillato...
Henderson, Brian; Ice, Lauren; Ates, Ozgur; Avetisyan, Albert; Beck, Reinhard; Belostotski, Stanislav; Bessuille, Jason; Brinker, Frank; Calarco, John; Carassiti, V.; Cisbani, E.; Ciullo, G.; Khaneft, Dmitry; Contalbrigo, Marco; De Leo, R.
2017-01-01
The OLYMPUS collaboration reports on a precision measurement of the positron-proton to electron-proton elastic cross section ratio, $\\it R_{2 \\gamma}$, a direct measure of the contribution of hard two-photon exchange to the elastic cross section. In the OLYMPUS measurement, 2.01 GeV electron and positron beams were directed through a hydrogen gas target internal to the DORIS storage ring at DESY. A toroidal magnetic spectrometer instrumented with drift chambers and time-of-flight scintillator...
International Nuclear Information System (INIS)
Alberi, G.; Bleszynski, M.; California Univ., Los Angeles; Santos, S.; Jaroszewicz, T.
1980-01-01
It is shown that the tensor asymmetries in the elastic proton-deuteron scattering at medium energies are very sensitive to the non-eikonal corrections to the Glauber model. This sensitivity originates from the fact that, in double scattering, the non-eikonal corrections affect in a different way the contributions coming from the S- and D-wave parts of the deuteron wave function. This leads to considerable change of the tensor asymmetries not only in the region of the interference between single and double scatterings, but also in the region of dominance of the double scattering. It is suggested that these effects should be taken into account in any careful analysis of the proton-deuteron polarization data, which has as a goal the extraction of the NN amplitudes. (author)
Elastic proton-deuteron backward scattering: relativistic effects and polarization observables
International Nuclear Information System (INIS)
Kaptari, L.P.; Semikh, S.S.
1997-10-01
The elastic proton-deuteron backward reaction is analyzed within a covariant approach based on the Bethe-Salpeter equation with 000. Lorentz boost and other relativistic effects in the cross section and spin correlation observables, like tensor analyzing power and polarization transfer etc., are investigated in explicit form. Results of numerical calculations for a complete set of polarization observables are presented. (orig.)
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.)
Kreutzfeldt, Kristof; Stenzel, Hasko
The ATLAS experiment with the ALFA sub-detector, provides a unique opportunity to measure elastic proton--proton scattering at the LHC at a centre-of-mass energy of $\\sqrt{s} = 7$ TeV, that has never been reached before. The ALFA detector is a tracking detector housed in Roman Pots, which makes it possible to measure elastically scattered protons down to very small scattering angles. From the proton tracks, measured during a LHC fill with special $\\beta^{*} = 90$ m beam optics, the differential elastic cross-section as a function of the four-momentum transfer squared $t$ is determined, and the total hadronic cross-section $\\sigma_\\text{tot}$, the nuclear slope parameter $B$ and further derived quantities are extracted by utilizing the optical theorem. The total hadronic cross-section is a fundamental parameter of strong interaction depending on the centre-of-mass energy. It has been measured for more than 50 years at different energies and accelerators, where a rise with energy was observed. A newly developed...
Microscopic analysis of proton elastic scattering in the range 80-200 MeV
International Nuclear Information System (INIS)
Dietrich, F.S.; Petrovich, F.
1983-01-01
A systematic comparison is made of differential cross-section and analyzing-power data on 12 C, 28 Si, 40 Ca, 90 Zr, and 208 Pb at 80-200 MeV with calculations based on the single-step folding-model approach to the optical potential. In these calculations, proton densities have been inferred from electron scattering results, with neutron densities either the same as for protons ( 12 C, 28 Si, 40 Ca) or with a small neutron skin consistent with 800-MeV proton scattering results ( 80 Zr, 208 Pb). The effective two-body interactions that have been used are the Love-Franey t-matrix, a density-dependent interaction based on the Paris potential (calculated by von Geramb), and finally the Brieva-Rook density-dependent central interaction used with the spin-orbit part of the Love-Franey interaction
Thermodynamic model for the elastic form factor in diffraction scattering of protons
International Nuclear Information System (INIS)
Grashin, A.F.; Evstratenko, A.S.; Lepeshkin, M.V.
1988-01-01
An explicit expression is obtained for the differential pp(p-bar)-scattering cross section in the diffraction-cone region by employing the thermodynamic model for the elastic form factor previously proposed in Ref. 4. Data for the energy region 16.3≤(s)/sup 1/2/ ≤546 GeV have been analyzed and significant deviations have been discovered from the commonly used approximations in the form of linear or quadratic exponentials
International Nuclear Information System (INIS)
Deb, P.K.; Amos, K.; Karataglidis, S.
2000-01-01
An extensive survey and analysis of cross section and analysing power data from proton elastic scattering at energies 25 to 40 MeV is presented. The data are compared with predictions obtained from a full folding specification of the proton-nucleus optical potentials. Isotope and energy variation of the data is explained
A fully microscopic model of 200 MeV proton-{sup 12}C elastic and inelastic scattering
Energy Technology Data Exchange (ETDEWEB)
Karataglidis, S; Dortmans, P J; Amos, K; de Swiniarski, R
1996-03-01
An effective two nucleon (NN) interaction in the nuclear medium is defined from an accurate mapping of the NN g matrices obtained by solving the Brueckner-Bethe-Goldstone equations for infinite nuclear matter. That effective interaction is used in a fully microscopic calculation of the nonlocal effective proton-{sup 12}C interaction from which are obtained predictions of the differential cross section and analysing power for 200 MeV elastic scattering. The relative motion wave functions so found are used as the distorted waves in a distorted wave approximation (DWA) study of select inelastic scattering events. The effective NN interaction is used as the transition operator in those calculations. The relevant nuclear spectroscopy for the elastic and DWA (p, p`) calculations is found from a full (0 + 2) {Dirac_h}{omega} shell model evaluation of the positive parity states while a restricted (1 + 3){Dirac_h}{omega} has been used to give the negative parity states. Results are compared with those of the 0p-shell model of Cohen and Kurath or with those based upon axially symmetric, projected Hartree-Fock calculations. The diverse structure model wave functions are assessed by using them in calculations to compare with measured longitudinal, transverse electric and transverse magnetic form factors from electron scattering to many of the excited states of {sup 12}C. Using those models of the structure of {sup 12}C in the completely microscopic model of the elastic and inelastic scattering of 200 MeV protons, good fits have been found to the cross section and analysing power data. 50 refs., 3 tabs., 20 figs.
Neutrino proton scattering and the isosinglet term
International Nuclear Information System (INIS)
White, D.H.
1990-01-01
Elastic neutrino proton scattering is sensitive to the SU(3) axial isosinglet term which is in turn dependent on the strangeness content of the proton. The uncertainties in the analysis of a neutrino proton elastic scattering experiment are discussed, and an experiment which is insensitive to many of the difficulties of the previous experiment is described
Study of the elastic scattering differential cross sections of a proton beam by a cesium target
International Nuclear Information System (INIS)
El Maddarsi, Mohamed.
1978-01-01
The elastic differential cross section of H + on Cs is studied experimentally and theoretically. The experimental device is described, after which the differential cross-section values obtained as a function of the laboratory angle are given for four incident energies: 13.4 eV, 15.1 eV, 17.7 eV and 24.2 eV. By means of an interaction potential of the quasi-molecule H + Cs the differential cross sections are calculated for the same incident energies; this calculation uses the semi-classical method of stationary phases which shows clearly the limits of conventional description and the changes introduced by quantum effects. Very good agreement is obtained between theoretical and experimental results, which shows that elastic scattering is very little perturbed by inelastic channels in this energy range. The estimated inelastic cross section at 24 eV is about 1.9 10 -15 cm 2 , corresponding to 1.6% of the scattering process [fr
Energy Technology Data Exchange (ETDEWEB)
Farag, M.Y.H.; Esmael, E.H. [Cairo University, Physics Department, Faculty of Science, Giza (Egypt); Maridi, H.M. [Cairo University, Physics Department, Faculty of Science, Giza (Egypt); Taiz University, Physics Department, Faculty of Applied Science, Taiz (Yemen)
2012-11-15
The proton elastic scattering data on some light exotic nuclei, namely, {sup 6,} {sup 8}He, {sup 9,} {sup 11}Li, and {sup 10,} {sup 11,} {sup 12}Be, at energies below than 100MeV/nucleon are analyzed using the single folding optical model. The real, imaginary, and spin-orbit parts of the optical potential (OP) are constructed only from the folded potentials and their derivatives using M3Y effective nucleon-nucleon interaction. These OP parts, their renormalization factors and their volume integrals are studied. The surface and spin-orbit potentials are important to fit the experimental data. Three model densities for halo nuclei are used and the sensitivity of the cross-sections to these densities is tested. The imaginary OP within high-energy approximation is used and compared with the single folding OP. This OP with few and limited fitting parameters, which have systematic behavior with incident energy, successfully describes the proton elastic scattering data with exotic nuclei. (orig.)
Polarisation parameter measurement in the proton-proton elastic scattering from 0.5 to 1.2 GeV
International Nuclear Information System (INIS)
Ducros, Yves
1970-01-01
The angular distribution of the polarisation parameter was measured in the proton-proton elastic - scattering at seven energies between 0.5 and 1.2 GeV. A polarized proton target was used. The results show a maximum of the polarisation parameter of 0.6, at 0.73 GeV. This maximum is due to the important increase of the total cross section between 0.6 and 0.73 GeV. At 1.2 GeV the angular distribution of the polarisation shows a minimum for a momentum transfer value of -1 (GeV/c) 2 . A phase shift analysis was done at 0.66 GeV, using all available experimental data at this energy. There is no evidence of a di-baryonic resonance in the 1 D 2 phase. (author) [fr
International Nuclear Information System (INIS)
Antonov, A.N.; Christov, Chr.V.; Nikolov, E.N.
1989-01-01
Differential cross-section of the 1.04 GeV - proton elastic scattering from 40 Ca is calculated within the Glauber-Sitenko theoretical scheme using the coherent density fluctuation model (CDFM). It is shown that the use of exact noneikonal expression for the two-body scattering amplitude (which describes the p-p data) leads to a satisfactory agreement with the experimental data. The influence of the flucton correlations on the differential cross-sections is considerable as the use of a realistic charge density distribution leads to a better agreement with the experimental data of the CDFM which is not for the case of the independent-particle model. 20 refs.; 4 figs
Antiproton-proton elastic scattering at 3.0 and 4.0 GeV/C
International Nuclear Information System (INIS)
Unamuno, S.
1965-01-01
This paper presents the results-obtained in studying the two-prong interactions observed in the Saclay 81 cm hydrogen bubble chamber exposed to the 3.0 and 4.0 GeV/c antiproton beams from CERN Proton-Synchroton. Total elastic cross-sections corresponding to both energies are given. The results are given. The results are compared with those of p-p scaterring at different energies and with those of p-p scattering. Several optical-models, from the simples one (the black disk model) to a rather elaborated, four-parameters model have been applied. These models can explain some of the experimental results but fail in predicting the angular distribution of large angle scattering. (Author)
Elastic scattering of intermediate energy protons on 4He and 12C
International Nuclear Information System (INIS)
Khan, Z.A.
1981-01-01
The elastic angular distribution and polarization of approx. equal to 1 GeV protons on 4 He and 12 C have been analysed using the recently proposed correlation expansion for the Glauber amplitude by retaining terms up to three-body density only. The calculations include Coulomb and spin effects. Using realistic form factors for target nuclei it is found that we need to consider only up to the second-order density term to provide a satisfactory explanation of both kinds of experimental data in the available momentum transfer region. The contribution of the three-body density term is only marginal except in 4 He differential cross-section in the cm angular range 45 0 0 . (orig.)
International Nuclear Information System (INIS)
Comparat, Vincent.
1975-01-01
In this work a high spatial resolution hodoscope is described. Scattered particles are detected in the image plane of a magnetic spectrometer by a proportional chamber with 96 wires of 1mm spacing. This hodoscope has been used for elastic and inelastic scattering experiments, of 156MeV protons, on 11 targets ranging from 12 C to 209 Bi. A phenomenological optical model calculation has been carried out to analyse the experimental elastic cross sections data. The dependance of the parameters as a function of the number of mass or the incident energy has been studied. The inelastic scattering results have been interpreted within the framework of the D.W.I.A. As the final results are dependant of the nucleon model, the optical potential parameters as well as the finite range approximation, several trials have been performed. Nevertheless, the DWIA seems to give about twice the experimental values for collective excitations in light or medium nuclei. The first order optical potential derived from the impulse approximation was calculated and the results compared to the experimental elastic cross sections. Several approximations were tested as non locality, off energy shell effects and the motion of the target nucleon. The usual approximation on these quantities are justified if the momentum transfer is less than 3fm -1 . The nucleon-nucleus transition matrix is obtained by solving the Lippmann-Schwinger equation, using the moment method. The first order optical potential derived from these calculations is not realistic. The intensity of the nucleon-nucleon transition is too important, and that explained the disagreement at low momentum transfers. This study shows that the multiple scattering expansion of the Lippmann-Schwinger equation, is not a good method to obtain the exact solution. It is better to do some approximations (i.e. of shell approximation) directly on the integral equation [fr
International Nuclear Information System (INIS)
Hojsik, M.; Gmuca, S.
1998-01-01
Relativistic microscopic calculations are presented for proton elastic scattering from 40 Ca at 500 MeV. The underlying target densities are calculated within the framework of the relativistic mean-field theory with several parameter sets commonly in use. The self consistency of the scalar and vector densities (and thus to relativistic mean-field parameters) is investigated. Recently, the relativistic impulse approximation (RIA) has been widely and repeatedly used for the calculations of proton-nucleus scattering at intermediate energies. These calculations have exhibited significant improvements over the nonrelativistic approaches. The relativistic impulse approximation calculations. in particular, provide a dramatically better description of the spin observables, namely the analyzing power, A y , and the spin-rotation function, Q, at least for energies higher than 400 MeV. In the relativistic impulse approximation, the Dirac optical potential is obtained by folding of the local Lorentz-invariant amplitudes with the corresponding nuclear densities. For the spin zero targets the scalar and vector terms give the dominant contributions. Thus the scalar and vector nuclear densities (both, proton and neutron ones) play the dominant role in the relativistic impulse approximation. While the proton vector densities can be obtained by unfolding from the empirically known charge densities, all other densities used rely to a great extent on theoretical models. The various recipes are used to construct the neutron vector densities and the scalar densities for both, neutrons and protons. In this paper we will study the sensitivity of the relativistic impulse approximation results on the various sets of relativistic mean-field parameters currently in use
Elimination of the 12 C and 16 O in the elastic scattering of 14 C by polarized protons
International Nuclear Information System (INIS)
Avila A, O.L.; Ramirez T, J.J.; Murillo O, G.; Fernandez B, M.
1991-04-01
The study of the elastic scattering of 14 C for polarized protons it provides information on the nuclear structure of 15 N. In the Tandem accelerator of the Nuclear Center in collaboration with the University of Notre Dame is carrying out this study to energy between 5.0 and 9.0 MeV in steps of 10 keV. The measures of differential section and vectorial analyzer power are subjected to shift analysis of phase being able to determine the parameters of the excited levels of 15 N that are it angular momentum, parity, level width and elastic width. The details of this experiment are presented in the ACEL-9102 technical report while in this work it was discussed the way in that contributions of 12 C and 16 O are eliminated that are present as impurities in our target of 14 C. At small angles the elastic components of these impurities are shoveled with the elastic of 14 C. In the experiment carried out in the Nuclear Center were take measures of differential section for 6 angles; 35, 45, 55, 65, 145 and 165 using surface barrier detectors. It is observed that it exists shovels at 35, 45, 55 and 65 while at 145 and 165 the 12 C, the 14 C and the 16 O are totally separate. With the purpose of being able to subtract of the elastic of 14 C the proportion of 12 C, it was decided to bombard a target of 12 C leaving the same geometry that had been used to bombard 14 C. With this also carried out the reaction 12 C (p,p) 12 C between 5.0 and 9.0 MeV in steps of 50 keV. Starting from these spectra are the integration (yield) of the elastic of 12 C. (Author)
Further application of angular momentum dependent potentials to proton elastic scattering
International Nuclear Information System (INIS)
Kobos, A.M.; Mackintosh, R.S.
1981-01-01
We extend our application of the iota-dependent model to a wider range of cases. We include more non-closed shell nuclei and some heavy nuclei as targets, getting better fits than previously found, with no substantial exceptions to the systematic properties of the iota-dependent potential. For one mass sequence we find shell effects, but note that the results would be more certain if more analysing powers data were available. A simple pattern of iota-dependence is a universal feature of proton scattering between 20 and 60 MeV. Since the effect on (p,p') is large the effect of iota-dependence on direct reactions should not be ignored. (author)
Current-current interaction picture for proton-proton scattering
International Nuclear Information System (INIS)
Clarke, D.J.; Lo, S.Y.
1979-01-01
The authors propose that color current - color current interaction is reponsible for small angle elastic proton proton scattering at asymptotic energy. Excellent fits are obtained for all data above 12 GeV/c which covers twelve orders of magnitude
International Nuclear Information System (INIS)
Swol, R.W. van.
1985-01-01
The transformation of the CERN Super Proton Synchrotron (SPS) from a fixed target machine into a colliding beam facility allowed the study of antiproton-proton scattering at a centre-of-mass (CM) energy of 546 GeV. This thesis describes the measurement of antiproton-proton elastic scattering and the antiproton-proton total cross section, sigmasub(tot)(anti pp), at the CERN anti pp Collider. The aim of the experiment is to establish the considerable rise with energy of the total cross section, which was predicted after the discovery of rising proton-proton total cross sections at the CERN Intersecting Storage Rings (ISR), covering an energy range of 20-60 GeV. The experimental method used for measuring sigmasub(tot)(anti pp) with an accuracy of 1-2% consists of the simultaneous measurement of both the elastic scattering event rate at small scattering angles and the inelastic interaction rate. Using the optical theorem, the total and the elastic cross sections can then be obtained without a determination of the machine luminosity. (Auth.)
Energy Technology Data Exchange (ETDEWEB)
Bagdasarian, Zara [Forschungszentrum Juelich (Germany)
2016-07-01
The most accepted approach to describe nucleon-nucleon (NN) interaction is the partial wave analysis (PWA). The goal of many experiments held at COSY-Juelich has been to provide PWA with valuable precision measurements at different energies aiming to cover the full angular range. This contribution reports on the differential cross section for proton-proton elastic scattering that has been measured at a beam energy of 1.0 GeV and in 200 MeV steps from 1.6 to 2.8 GeV at centre-of-mass angles between about 10 and 30 degrees. The ANKE collaboration and the COSY machine crew have jointly developed a very accurate method for determining the absolute luminosity in an experiment at an internal target position. The technique relies on measuring the energy losses due to the electromagnetic interactions of the beam as it passes repeatedly through the thin target and measuring the shift of the revolution frequency by studying the Schottky spectrum. This powerful technique allows one to measure the absolute differential cross section for elastic pp scattering with the accuracy of typically 3%. After extrapolating the differential cross sections to the forward direction, the results are broadly compatible with the predictions of forward dispersion relations. Finally, it is shown that the data have a significant impact on the partial wave analysis.
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.)
Energy Technology Data Exchange (ETDEWEB)
Heinz, Christian; Dueren, Michael; Kreutzfeldt, Kristof; Stenzel, Hasko [JLU Giessen (Germany)
2015-07-01
The ALFA (Absolute Luminosity for ATLAS) Roman Pot detector system is part of the forward instrumentation of ATLAS located about 240 m away from the interaction point in the LHC tunnel. ALFA consists of a scintillating fibre tracker housed in vertical Roman Pots which enables the measurement of elastic proton-proton scattering at small scattering angles. In 2012 data were recorded at a centre-of-mass energy of √(s) = 8 TeV during a fill with special beam optics of the LHC with β* = 90 m and parallel-to-point focusing. The four-momentum transfer t is measured for elastically scattered protons and the differential elastic cross section is measured. In this talk a preliminary determination of the total cross section and of the slope of the elastic cross section at small vertical stroke t vertical stroke obtained from a fit to the differential cross section using the optical theorem is reported.
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)
Rille, E.; Peacher, J.L.; Redd, E.; Kvale, T.J.; Seely, D.G.; Blankenship, D.M.; Olson, R.E.; Park, J.T.
1984-01-01
Elastic angular differential cross sections for small-angle scattering of protons by atomic hydrogen have been measured. The technique utilized unambigously distinguishes the elastically and inelastically scattered ions. The cross sections fall monotonically by 3 orders of magnitude in the angular range from 0.5 to 3.0 mrad, in the center-of-mass system. The experimental data obtained are in very good agreement with a multistate calculation and in fair agreement with both our Glauber-approximation and classical-trajectory Monte Carlo results
New results on kaon-proton elastic scattering at large momentum transfers
International Nuclear Information System (INIS)
Asa'd, Z.; Coupland, M.; Davis, D.G.; Duff, B.G.; Fearnley, T.; Heymann, F.F.; Imrie, D.C.; Lowndes, R.; Lush, G.J.; Phillips, M.; Baglin, C.; Guillaud, J.P.; Poulet, M.; Yvert, M.; Hansen, J.D.; Myrheim, J.; Brobakken, K.; Buran, T.; Buzzo, A.; Ferroni, S.; Gracco, V.; Helgaker, P.; Kirsebom, K.; Santroni, A.; Skjevling, G.; Soerensen, S.O.
1983-01-01
Measurements of the K - p and K 8 p elastic differential cross sections at 20 and 50 GeV/c, respectively, have been made in the momentum transfer range 0.7< vertical stroketvertical stroke<8.0 GeV/c. (orig.)
International Nuclear Information System (INIS)
Dortmans, P.J.; Amos, K.
1997-01-01
Two nucleon (NN) effective interactions based upon two-nucleon g matrices have been used in fully microscopic calculations of nonlocal proton-nucleus optical potentials for protons with energies between 65 and 400 MeV. Excellent predictions of the differential cross sections, analysing powers and spin rotations for scattering angles to 60 deg result. (authors)
Proton-proton elastic scattering at 50 GeV/c incident momentum in the momentum transfer range 0.82
International Nuclear Information System (INIS)
Baglin, C.; Guillaud, J.P.; Poulet, M.; Myrheim, J.; Asa'd, Z.; Coupland, M.; Davis, D.G.; Duff, B.G.; Fearnley, T.; Heymann, F.F.; Imrie, D.C.; Lush, G.J.; Phillips, M.; Brom, J.M.; Kenyon Gjerpe, I.; Buran, T.; Buzzo, A.; Ferroni, S.; Gracco, V.; Kirsebom, K.; Macri, M.; Santroni, A.; Skjevling, G.; Soerensen, S.O.
1983-01-01
A measurement of the proton-proton elastic differential cross section at 50 GeV/c incident momentum in the momentum transfer range 0.8 2 is presented. The data are compared to pp data at lower and higher energies, and to some model predictions. (orig.)
Qattan, I. A.
2017-05-01
Background: The inconsistency in the results obtained from the Rosenbluth separation method and the high-Q2 recoil polarization results on the ratio μpGEp/GMp implies a systematic difference between the two techniques. Several studies suggest that missing higher-order radiative corrections to elastic electron-proton scattering cross section σR(ɛ ,Q2) and in particular hard two-photon-exchange (TPE) contributions could account for the discrepancy. Purpose: In this work, I improve on and extend to low and high Q2 values the extractions of the ɛ dependence of the real parts of the TPE amplitudes relative to the magnetic form factor, as well as the ratio Pl/PlBorn(ɛ ,Q2) by using world data on σR(ɛ ,Q2) with an emphasis on precise new data covering the low-momentum region which is sensitive to the large-scale structure of the nucleon. Method: I combine cross section and polarization measurements of elastic electron-proton scattering to extract the TPE amplitudes. Because the recoil polarization data were confirmed "experimentally" to be essentially independent of ɛ , I constrain the ratio Pt/Pl(ɛ ,Q2) to its ɛ -independent term (Born value) by setting the TPE contributions to zero. This allows for the amplitude YM(ɛ ,Q2) and σR(ɛ ,Q2) to be expressed in terms of the remaining two amplitudes YE(ɛ ,Q2) and Y3(ɛ ,Q2) which in turn are parametrized as second-order polynomials in ɛ and Q2 to reserve as possible the linearity of σR(ɛ ,Q2) as well as to account for possible nonlinearities in the TPE amplitudes. Furthermore, I impose the Regge limit which ensures the vanishing of the TPE contributions to σR(ɛ ,Q2) and the TPE amplitudes in the limit ɛ →1 . Results: I provide simple parametrizations of the TPE amplitudes, along with an estimate of the fit uncertainties. The extracted TPE amplitudes are compared with previous phenomenological extractions and TPE calculations. The Pl/PlBorn ratio is extracted by using the new parametrizations of the TPE
Determination of 40Ca and 48Ca matter densities by 600 MeV and 1 GeV proton elastic scattering
International Nuclear Information System (INIS)
Brissaud, I.; Campi, X.
1979-02-01
The 600MeV and 1GeV data of proton elastic scattering on 40 Ca and 48 Ca have been analyzed in the framework of the Glauber model. The matter distributions are extracted from the data in an approximately model-independent form based on a Fourier series expansion. A similar method is used to deduce directly the 48 Ca- 40 Ca neutron density difference
Two-Photon Exchange Effects in Elastic Electron-Proton Scattering
Energy Technology Data Exchange (ETDEWEB)
Johnson, Myriam James [Argonne National Lab. (ANL), Argonne, IL (United States)
2013-08-01
Two methods, Rosenbluth separation and polarization transfer, can be used to extract the proton form factor ratio μp G_{Ep}/G_{Mp}, but they do not yield the same results. It is thought that the disagreement is due to two photon exchange corrections to the differential cross sections. High precision proton Rosenbluth extractions were carried out at 102 kinematics points spanning 16 values of momentum transfer Q^{2}, from 0.40 to 5.76 GeV^{2}. Reduced cross sections were found to 1.1% or better for Q^{2} less than 3 GeV^{2} increasing to 4% at 5.76 GeV^{2} The form factor ratios were determined to 1:5-3% for Q^{2} < 1.5 GeV^{2}, increasing to 9% by 3 GeV^{2} and rapidly above. Our data agrees with prior Rosenbluth, improving upon it the 1.0 - 2.0 GeV^{2} range to conclusively show a separation from polarization transfer where it had not been certain before. In addition, reduced cross sections at each Q^{2} were tested for nonlinearity in the angular variable. Such a departure from linearity would be a signature of two photon exchange effects, and prior data had not been sufficiently precise to show nonzero curvature. Our data begins to hint at negative curvature but does not yet show a significant departure from zero.
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.
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
International Nuclear Information System (INIS)
Doll, P.
1990-02-01
Neutron-proton scattering as fundamental interaction process below and above hundred MeV is discussed. Quark model inspired interactions and phenomenological potential models are described. The seminar also indicates the experimental improvements for achieving new precise scattering data. Concluding remarks indicate the relevance of nucleon-nucleon scattering results to finite nuclei. (orig.) [de
Energy Technology Data Exchange (ETDEWEB)
Waidyawansa, Dinayadura Buddhini [Ohio Univ., Athens, OH (United States)
2013-08-01
The beam normal single spin asymmetry generated in the scattering of transversely polarized electrons from unpolarized nucleons is an observable of the imaginary part of the two-photon exchange process. Moreover, it is a potential source of false asymmetry in parity violating electron scattering experiments. The Q{sub weak} experiment uses parity violating electron scattering to make a direct measurement of the weak charge of the proton. The targeted 4% measurement of the weak charge of the proton probes for parity violating new physics beyond the Standard Model. The beam normal single spin asymmetry at Q{sub weak} kinematics is at least three orders of magnitude larger than 5 ppb precision of the parity violating asymmetry. To better understand this parity conserving background, the Q{sub weak} Collaboration has performed elastic scattering measurements with fully transversely polarized electron beam on the proton and aluminum. This dissertation presents the analysis of the 3% measurement (1.3% statistical and 2.6% systematic) of beam normal single spin asymmetry in electronproton scattering at a Q2 of 0.025 (GeV/c)2. It is the most precise existing measurement of beam normal single spin asymmetry available at the time. A measurement of this precision helps to improve the theoretical models on beam normal single spin asymmetry and thereby our understanding of the doubly virtual Compton scattering process.
International Nuclear Information System (INIS)
Schmitt, R.
1986-01-01
With the Erlangen QDQ magnetic spectrometer angular distributions of the depolarization in the elastic scattering of protons on 27 Al, 89 Y at 11 MeV and 1 H at 12 MeV were measured. The evaluation was performed for yttrium and aluminium by adding of additional terms in the optical model which regard the spin-spin interaction. The optical-model parameter without spin-spin potentials were stated by measurements of the cross section and the analyzing power in the 4π scattering chamber in Erlangen at several energies. The calculation of the depolarization which emerges because of the spin-spin interaction was performed by means of DWBA. The depolarization of the proton-proton scattering was evaluated by scattering-phase analysis. The fits were thereby performed on analyzing-power data. The electrical P-wave scattering phases resulted to δ 10 = 4.442±0.121, δ 11 = -2.515±0.026, and δ 12 = 0.937±0.038 (all in degrees). (orig./HSI) [de
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
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.
International Nuclear Information System (INIS)
Ilieva, Stoyanka
2008-01-01
In the current experiment, the differential cross sections for proton elastic scattering on the isotopes 7,9,10,11,12,14 Be and 8 B were measured. As results from the experiment, the absolute differential cross sections dσ/dt as a function of the four momentum transfer t were obtained. In this work the differential cross sections for elastic p- 12 Be, p- 14 Be and p- 8 B scattering at low t (t≤0.05(GeV/c) 2 ) are presented. The measured cross sections were analyzed within the Glauber multiple-scattering theory using different density parameterizations, and the nuclear matter density distributions and radii of the investigated isotopes were determined. The determined rms matter radius is 3.11±0.04±0.13 fm. In the case of the 12 Be nucleus the results showed an extended matter distribution as well. For this nucleus a matter radius of 2.82±0.03±0.12 fm was determined. An interesting result is that the free 12 Be nucleus behaves differently from the core of 14 Be and is much more extended than it. Preliminary experimental results for the isotope 8 B are also presented. An extended matter distribution was obtained (though much more compact as compared to the neutron halos). A proton halo structure was observed for the first time with the proton elastic scattering method. The deduced matter radius is 2.60±0.02±0.26 fm. Results from the feasibility studies of the EXL detector setup, performed at the present ESR storage ring, are presented. (orig.)
International Nuclear Information System (INIS)
Boissinot, S.
2013-01-01
The studies of structure and spectroscopy performed on radioactive nuclei during the last three decades have shown that the nuclear shell structure changes towards the drip-line and local magic numbers may appear. Doubly-magic nuclei are very rare but represent stringent tests for theories and their modelling of the nuclear interaction. In this context, we have investigated the structure and spectroscopy of the drip-line doubly-magic nucleus 24 O via proton elastic and inelastic scattering (p,p'). The experiment was performed at Riken in the BigRIPS line, using the 24 O beam produced at 263 MeV/n with RIBF with a high intensity (1780/s), and the state-of-the-art MUST2 charged particle detector. The analysis of the data gives the reconstruction of: the 24 O excitation energy spectrum up to 35 MeV with the scattered proton kinematics using the missing mass method, and the angular distribution of exclusive (p,p) elastic cross section between 4 and 30 degrees c.m. via a triple coincidence nucleus-proton-nucleus. Below the two-neutron separation threshold (S2n) the statistics is too low to obtain the two excited states measured by previous experiments done at lower incident energies. Above the S 2n structures are observed for the first time due to the large excitation energy range of the excitation spectra. The measurement of the excited states located at these energies would allow to test theoretical studies of low-energy dipole excitation in light neutron-rich nuclei. The statistics obtained for proton elastic scattering is sufficient to extract the exclusive (p,p) angular distributions of the 24 , 23 , 22 , 21 O isotopes. These results constitute a new benchmark to explore proton-nucleus interaction potential features around 260 MeV/n. The comparison of elastic data set to the reaction calculations done with the microscopic reaction approach based on the G-matrix density-dependent potential indicates that this potential is suitable. However, it remains to include
Energy Technology Data Exchange (ETDEWEB)
Heinz, Christian; Stenzel, Hasko; Dueren, Michael [2. Physikalisches Institut, Universitaet Giessen (Germany)
2016-07-01
The ALFA (Absolute Luminosity for ATLAS) Roman Pot detector system is part of the forward instrumentation of ATLAS located about 240 m away from the interaction point in the LHC tunnel in both directions. ALFA consists of a scintillating fibre tracker housed in vertical Roman Pots which enables the measurement of elastic proton-proton scattering at small scattering angles. In 2012 data were recorded at a centre-of-mass energy of √(s) = 8 TeV during a fill with special beam optics of the LHC with β* = 90 m and parallel-to-point focusing. The four-momentum transfer t is measured for elastically scattered protons and used to extract the differential elastic cross section. In this talk a preliminary determination of the total cross section and of the slope of the elastic cross section at small vertical stroke t vertical stroke obtained from a fit to the differential cross section using the optical theorem is reported. In addition a second run at √(s) = 8 TeV with a special beam optics of β* = 1 km, providing access to the Coulomb-nuclear interference region, is being analysed. Preliminary analysis results from this run are presented as well.
International Nuclear Information System (INIS)
Akchurin, N.; Langland, J.; Onel, Y.; Bonner, B.E.; Corcoran, M.D.; Cranshaw, J.; Nessi-Tedaldi, F.; Nessi, M.; Nguyen, C.; Roberts, J.B.; Skeens, J.; White, J.L.; Bravar, A.; Giacomich, R.; Penzo, A.; Schiavon, P.; Zanetti, A.; Bystricky, J.; Lehar, F.; de Lesquen, A.; van Rossum, L.; Cossairt, J.D.; Read, A.L.; Derevschikov, A.A.; Matulenko, Y.A.; Meschanin, A.P.; Nurushev, S.B.; Patalakha, D.I.; Rykov, V.L.; Solovyanov, V.L.; Vasiliev, A.N.; Grosnick, D.P.; Hill, D.A.; Laghai, M.; Lopiano, D.; Ohashi, Y.; Shima, T.; Spinka, H.; Stanek, R.W.; Underwood, D.G.; Yokosawa, A.; Funahashi, H.; Goto, Y.; Imai, K.; Itow, Y.; Makino, S.; Masaike, A.; Miyake, K.; Nagamine, T.; Saito, N.; Yamashita, S.; Iwatani, K.; Kuroda, K.; Michalowicz, A.; Luehring, F.C.; Miller, D.H.; Maki, T.; Pauletta, G.; Rappazzo, G.F.; Salvato, G.; Takashima, R.
1993-01-01
The analyzing power A N of proton-proton elastic scattering in the Coulomb-nuclear interference region has been measured using the 200-GeV/c Fermilab polarized proton beam. A theoretically predicted interference between the hadronic non-spin-flip amplitude and the electromagnetic spin-flip amplitude is shown for the first time to be present at high energies in the region of 1.5x10 -3 to 5.0x10 -2 (GeV/c) 2 four-momentum transfer squared, and our results are analyzed in connection with theoretical calculations. In addition, the role of possible contributions of the hadronic spin-flip amplitude is discussed
International Nuclear Information System (INIS)
Qattan, I. A.; Alsaad, A.
2011-01-01
The most recent electron-proton elastic scattering data were re-analyzed using an empirical parametrization of the two-photon-exchange (TPE) effect contributions to σ R . The TPE effect contribution F(Q 2 ,ε) was double Taylor series expanded as a polynomial of order n keeping only terms linear in ε to account for the experimentally observed and verified linearity of the Rosenbluth plots. We fix the ratio R=G Ep /G Mp to be that obtained from a fit to the recoil-polarization data and parametrize σ R first by a three-parameter formula (fit I) and then by a two-parameter formula (fit III). In contrast to previous analyses, the fit parameter G Mp 2 as obtained from these fits is either smaller or equal to the values obtained from our conventional Rosenbluth fit (fit II) but never larger. The ratio g(Q 2 )/G Mp 2 which represents the ratio of the TPE and one-photon-exchange (OPE) effect contributions to the intercept of σ R is large and it ranges 3%-88%. The ratio R 1γx2γ =τf(Q 2 )/G Ep 2 which represents the ratio of the TPE and OPE effect contributions to the slope of σ R is also large, reaching a value of 12.0-14.4 at Q 2 = 5.25 (GeV/c) 2 . The ratio R 1γx2γ as obtained from fits I and III is consistent, within error, with those obtained from previous analyses. Our formulas seem to explain the linearity of σ R . Moreover, our analysis shows that the extracted G Ep 2 and G Mp 2 using the conventional Rosenbluth separation method can in fact be broken into the usual OPE and TPE contributions. Therefore, σ R can in fact be derived under weaker conditions than those imposed by the Born approximation. Our results show that the TPE amplitudes, g(Q 2 )/G Mp 2 and f(Q 2 )/G Mp 2 , are sizable and grow with Q 2 value up to Q 2 ∼6 (GeV/c) 2 in agreement with previous studies. A revision of and comparison to previous analyses are also presented.
Measurement of the analyzing power for pion-proton elastic scattering between 471 and 687 MeV/c
International Nuclear Information System (INIS)
Mokhtari-Amirmajdi, A.
1984-01-01
The analyzing power, A/sub N/, has been measured for π/sup +/-/p → π/sup +/-/p at 471, 547, 625, and 687 MeV/c in an angular range corresponding to -0.9 less than or equal to cos(theta)/sub cm/ less than or equal to 0.8. A polarized proton target with polarization axis normal to the scattering plane was used. The scattered pion and recoil proton were detected in coincidence, using a magnetic spectrometer and a wire chamber/scintillator array, except in cases where one of the particles was kinematically inaccessible. Statistical uncertainties in the data are as low as 0.02; systematic uncertainties are estimated to be less than 5%. The π - p data are characterized by large values of analyzing power, and rapid variations in the angular distribution with incident momentum. The measurements are compared with the results of existing partical wave analysis
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.
International Nuclear Information System (INIS)
Adams, D.L.
1986-10-01
Analyzing powers and spin transfer coefficients which describe the elastic scattering of polarized protons from a polarized deuteron target have been measured. The energy of the proton beam was 800 MeV and data were taken at laboratory scattering angles of 7, 11, 14, and 16.5 degrees. One analyzing power was also measured at 180 degrees. Three linearly independent orientations of the beam polarization were used and the target was polarized parallel and antiparallel to the direction of the beam momentum. The data were taken with the high resolution spectrometer at the Los Alamos Meson Physics Facility (experiment 685). The results are compared with multiple scattering predictions based on Dirac representations of the nucleon-nucleon scattering matrices. 27 refs., 28 figs., 4 tabs
Energy Technology Data Exchange (ETDEWEB)
Kreutzfeldt, Kristof; Dueren, Michael; Heinz, Christian; Stenzel, Hasko [2. Physikalisches Institut, Universitaet Giessen (Germany)
2015-07-01
The ALFA (Absolute Luminosity for ATLAS) detector is one of the ATLAS forward detectors located about 240 m away from the interaction point in the LHC tunnel. ALFA is a scintillating fibre tracking detector housed in Roman pots and designed to measure elastic proton-proton scattering up to the smallest scattering angles. In 2011 data were taken at a centre-of-mass energy of √(s) = 7 TeV during a special low intensity fill of LHC with high β* = 90 m beam optics. Results of the measurement of the differential elastic cross section dσ/dt, the total cross section σ{sub tot}, the nuclear slope B and other derived quantities are presented in this talk. In the analysis the luminosity determination, the fine tuning of beam optics parameters and a data-driven method to determine the reconstruction efficiency are emphasized.
International Nuclear Information System (INIS)
Kunne, R.A.
1988-01-01
An intermediate energy antiproton proton (anti pp) elastic scattering experiment is described. The data comprise a set of 15 measurements of the differential cross section and the asymmetry between 497 and 1550 MeV/c antiproton momentum. The measurements were carried out using the high quality antiproton beam provided by the Low Energy Antiproton Ring (LEAR) at CERN. A conventional polarized target was used, consisting of pentanol. The motivation for the measurements is the study of the anti pp interaction by providing data on the spin observable A on in a momentum range where it has never been measured before. 56 refs.; 55 figs.; 40 tabs
International Nuclear Information System (INIS)
Ambrosio, M.; Anzivino, G.; Barbarino, G.; Paternoster, G.; Patricelli, S.; Becker, U.; Kantardjian, G.; Owen, D.L.; Paradiso, J.; Carboni, G.; Pisa Univ.
1982-01-01
We measured the elastic scattering of αα at √S = 126 GeV and of αp at √S = 89 GeV. For αα, the differential cross section dsigma/dt has a diffractive pattern with minima at vertical stroke t vertical stroke = 0.10 and 0.38 GeV 2 . At small vertical stroke t vertical stroke = 0.05 - 0.07 GeV 2 , this cross section behaves like exp [(100 +- 10)t]. Extrapolating a fit to the data to the optical point, we obtained for the total cross section αsub(tot)(αα) = 250 +- 50 mb and an integrated elastic cross section sigmasub(el)(αα) = 45 +- 15 mb. Another method of estimating sigmasub(tot)(αα), based on measuring the interaction rate, yielded 295 +- 40 mb. For αp, dsigma/dt has a minimum at vertical stroke t vertical stroke = 0.20 GeV 2 , and for 0.05 2 behaves like exp[(41 +- 2)t]. Extraolating this slope to vertical stroke t vertical stroke = 0, we found sigmasub(tot)(αp) = 130 +- 20 and sigmasub(el)(αp) = 20 +- 4 mb. Results on pp elastic scattering at √s = 63 GeV agree with previous ISR experiments. (orig.)
International Nuclear Information System (INIS)
Jardillier, Johann
1999-01-01
In the quark model, the proton is described as a system of three quarks UUD. However, recent experiments (CERN, SLAC) have shown that the strange quarks may contribute in a significant way to the mass and the spin of the proton. The HAPPEX experiment gives one further knowledge about the question of the role the strange quarks play inside the proton. It measures parity violating asymmetry in the scattering of polarized electrons from a proton because the latter is sensitive to the contribution of the strange quarks to the electromagnetic form factors of the nucleon. The observed asymmetry is in the order of a few ppm (part per million). The main difficulty of the experiment is to identify, to estimate and to minimize, as much as possible, all the systematic effects which could give rise to false asymmetries. This thesis discusses the principle of the HAPPEX experiment, its implementation at the Jefferson Lab (JLab), the processing and the analysis of the data, the systematic errors, and finally presents the result of the first data taking (1999) and its present interpretation. The HAPPEX experiment has measured, at Q 2 = 0.5 (GeV/c) 2 , a strange quarks contribution of (1.0 ± 2.3)% to the electromagnetic form factors of the nucleon. The statistics and the systematic effects (measure of the electron beam polarization and knowledge of the neutron electric form factor) contribute equally to the error. (author)
Impact parameter analysis of proton-antiproton elastic scattering from √s=7.6 GeV to √s=546 GeV
International Nuclear Information System (INIS)
Fearnley, T.
1985-09-01
The proton-antiproton elastic profile function GAMMA (b) and inelastic overlap function Gsub(in)(b) are calculated from a coherent set of proton-antiproton elastic scattering data at Psub(L)=30 and 50 GeV/c (√s=7.6 and 9.8 GeV), and at √s=53 and 546 GeV. The energy dependence of Gsub(in)(b) is studied in the low energy regime and in the high energy regime. The increase of the inelastic cross section from 50 GeV/c to 30 GeV/c and from √s=53 GeV to √s=546 GeV is found to originate from a peripheral increase of Gsub(in) around 1 fm, accompanied by a non-negligible central increase. The proton-antiproton collision at √s=53 GeV is shown to be slightly less absorptive centrally than pp at this energy, while it is more absorptive peripherally around 1.2 fm. The inelastic overlap functions strongly disagree with the predictions of geometrical scaling and factorizing eikonal models, both in the low energy regime psub(L)=30-50 GeV/c and in the high energy regime √s=53-546 GeV
Small-angle elastic scattering of 40 and 50 GeV/c negative pions on protons
International Nuclear Information System (INIS)
Ioan, I.X.
1978-01-01
A measurement of π - p forward elastic differential cross sections at 40 and 50 keV/c is presented. The obtained ratio between the real and the imaginary part of strong amplitudes is compared with several phenomenological models proposed, in order to explain the rising total cross-sections at high energies. The data were obtained in the framework of a Dubna-UELA collaboration at Serpukhov. A brief description of the experimental apparatus is presented in the first chapter. It consists of a narrow-angle magnetostrictive wire spark chamber spectrometer. The information from six proportional wire chambers was used in an analogue electronics system to reject the scattered pions under a fixed minimum angle. The data were written on magnetic tape by a computer, which also provided on-line analysis of the quality of the data. The second chapter deals with the main features of the off-line analysis program. Processing the in-put data, particle trajectories reconstruction, preliminary event selection could be performed and by a SUMX-type program, the kinematic reconstruction and selection of elastic scattering events by appropriate cuts have been also obtained. The momentum transfer dependent corrections are presented in the next chapter. The accumulated data were corrected by substracting empty target back-grounds and inelastic events. Geometric and program efficiency were evaluated by means of the Monte-Carlo methods. The multiple Coulomb scattering was also included. The fitted differential cross-sections as functions of four-momentum transfers are presented in the fourth chapter and the ratio between the real and imaginary part of the forward amplitude, evaluated in the nuclear-Coulomb interference region. The results are discussed comparatively to a number of theoretical models, in the last chapter. Coupled with the new available data, these results are shown to be consistent with the rising of the total cross sections predicted by the dispersion relations and some
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
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
Energy Technology Data Exchange (ETDEWEB)
Swiniarski, R de [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1967-10-01
The elastic and inelastic scattering of the 18.6 MeV polarized proton beam from the Saclay variable energy cyclotron has been studied for the following nuclei: {sup 48}Ti, {sup 50}Ti, {sup 52}C, {sup 54}Fe, {sup 56}Fe, {sup 58}Ni, {sup 62}Ni, {sup 64}Ni, {sup 63}Cu: the targets {sup 52}Cr, {sup 60}Ni and {sup 62}Ni have also been investigated at 16.5 MeV. The measured asymmetries for the strong l = 2 transitions tend to fall into two categories, distinguished by the magnitude of the asymmetries at 30 degrees and 90 degrees. For the transitions studied, only those to the first 2+ state of the 28-neutron nuclei present large asymmetries at these angles. Strong l = 3 and l = 4 transitions show also interesting variations. When the entire optical potential is deformed, coupled channels or DWBA calculations predict the 'small' l = 2 asymmetry reasonably well, but only an abnormal increase of the strength of the spin-orbit distortion or the introduction of an imaginary and negative spin-orbit potential can reproduce the amplitude of the large asymmetries. Calculations with a microscopic model indicate that the asymmetry is sensitive to the form factor and no important differences were found between S=0 and S=1 predictions. (author) [French] Nous avons etudie la diffusion elastique et inelastique a l'aide du faisceau de protons polarises du cyclotron a energie variable de Saclay a 18.6 MeV pour les cibles suivantes: {sup 48}Ti, {sup 50}Ti, {sup 52}Cr, {sup 54}Fe, {sup 56}Fe, {sup 58}Ni, {sup 62}Ni, {sup 63}Cu et {sup 64}Ni: les cibles {sup 52}Cr, {sup 60}Ni et {sup 62}Ni ont egalement ete etudiees a 16.5 MeV. Les asymetries mesurees pour les transitions fortement excitees l = 2 se divisent en deux groupes differant par l'amplitude de l'asymetrie a 30 degres et 90 degres. Seules les asymetries mesurees pour les premiers niveaux 2+ des noyaux a couche complete en neutrons (N=28) sont tres grandes a ces angles. Les asymetries mesurees pour les niveaux 3{sup -} et 4{sup
Proton nuclear scattering radiography
International Nuclear Information System (INIS)
Saudinos, J.
1982-04-01
Nuclear scattering of protons allows to radiograph objects with specific properties: 3-dimensional radiography, different information as compared to X-ray technique, hydrogen radiography. Furthermore the nuclear scattering radiography (NSR) is a well adapted method to gating techniques allowing the radiography of fast periodic moving objects. Results obtained on phantoms, formalin fixed head and moving object are shown and discussed. The dose delivery is compatible with clinical use, but at the moment, the irradiation time is too long between 1 and 4 hours. Perspectives to make the radiograph faster and to get a practical method are discussed
International Nuclear Information System (INIS)
Simon, A.J.
1993-07-01
The proton-proton absolute elastic differential cross section, σ pp (θ), has been measured at incident proton beam energies of 491.9, 575.5, 641.6, 728.2, and 793.0 MeV at laboratory scattering angles of ∼15 degree to ∼42 degree with a total uncertainty on the order of 1%. The measurements were made at the Clinton P. Anderson Los Alamos Meson Physics Facility (LAMPF) and employed a new beam counting technique which provided a better overall beam normalization compared to previous experiments of this type. The cross section was measured with CH 2 targets and a primary liquid, LH 2 , target to determine the uncertainties in some systematic corrections. Extreme care was taken to reduce individual systematic errors to less than 0.5%
Energy Technology Data Exchange (ETDEWEB)
Apokin, V D; Vasiliev, A N; Derevshchikov, A A; Matulenko, Yu A; Meschanin, A P; Mysnik, A I; Nurushev, S B; Saraykin, A I; Siksin, V V; Smirnov, E V [Gosudarstvennyj Komitet po Ispol' zovaniyu Atomnoj Ehnergii SSSR, Serpukhov. Inst. Fiziki Vysokikh Ehnergij
1976-04-19
Differential cross sections for the elastic scattering of negative pions on protons, as well as total cross sections have been measured for the incident momentum range from 33 up to 60 GeV/c. The values for four-momentum transfer were within the limits of -(10/sup -3/-8x10/sup -2/) (GeV/c)/sup 2/. The energy dependence of the ratio rho(0) of the real part of the forward elastic scattering amplitude to the imaginary part has been determined from the experimental data. The magnitude rho(0) smoothly increases from (-10.9+-1.2)% at momenta 33.52 GeV/c up to (-1.8+-1.8)% at 59.4 GeV/c. The results obtained are compared with the predictions of theoretical models.
Energy Technology Data Exchange (ETDEWEB)
Subedi, Adesh [Mississippi State Univ., Mississippi State, MS (United States)
2014-12-01
The Qweak experiment has taken data to make a 2.5% measurement of parity violating elastic e+p asymmetry in the four momentum transfer region of 0.0250 (GeV/c)^{2}. This asymmetry is proportional to the weak charge of the proton, which is related to the weak mixing angle, sin^{2}(theta_W). The final Qweak measurement will provide the most precise measurement of the weak mixing angle below the Z^{0} pole to test the Standard Model prediction. A description of the experimental apparatus is provided in this dissertation. The experiment was carried out using a longitudinally polarized electron beam of up to 180 microampere on a 34.5 cm long unpolarized liquid hydrogen target. The Qweak target is not only the world's highest cryogenic target ever built for a parity experiment but also is the least noisy target. This dissertation provides a detailed description of this target and presents a thorough analysis of the target performance. Statistical analysis of Run 1 data, collected between Feb - May 2011, is done to extract a blinded parity violating asymmetry of size -299.7 ± 13.4 (stat.) ± 17.2 (syst.) ± 68 (blinding) parts-per-billion. This resulted in a preliminary proton's weak charge of value 0.0865 ± 0.0085, a 9% measurement. Based on this blinded asymmetry, the weak mixing angle was determined to be sin^{2}(theta_W) = 0.23429 ± 0.00211.
Lukyanov, V. K.; Kadrev, D. N.; Zemlyanaya, E. V.; Spasova, K.; Lukyanov, K. V.; Antonov, A. N.; Gaidarov, M. K.
2015-03-01
The density distributions of 10Be and 11Be nuclei obtained within the quantum Monte Carlo model and the generator coordinate method are used to calculate the microscopic optical potentials (OPs) and cross sections of elastic scattering of these nuclei on protons and 12C at energies E energy approximation. In this hybrid model of OP the free parameters are the depths of the real and imaginary parts obtained by fitting the experimental data. The well-known energy dependence of the volume integrals is used as a physical constraint to resolve the ambiguities of the parameter values. The role of the spin-orbit potential and the surface contribution to the OP is studied for an adequate description of available experimental elastic scattering cross-section data. Also, the cluster model, in which 11Be consists of a n -halo and the 10Be core, is adopted. Within the latter, the breakup cross sections of 11Be nucleus on 9Be,93Nb,181Ta , and 238U targets and momentum distributions of 10Be fragments are calculated and compared with the existing experimental data.
Energy Technology Data Exchange (ETDEWEB)
Asa' d, Z.; Coupland, M.; Davis, D.G.; Duff, B.G.; Fearnley, T.; Heymann, F.F.; Imrie, D.C.; Lush, G.J.; Phillips, M. (University Coll., London (UK)); Baglin, C.
1985-06-24
Results are presented from experiment WA7 at the CERN SPS, which has measured the elastic differential cross sections of ..pi..sup(+-)p, Ksup(+-)p, anti pp and pp at incident momenta of 20, 30 and 50 GeV/c. The measurements cover the momentum transfer range 0.5 < vertical stroketvertical stroke < 8 (GeV/c)/sup 2/, corresponding to c.m. scattering angles between 10/sup 0/ and 50/sup 0/. The experimental set-up, trigger logic and data analysis are described. The experimental results are compared with existing meson-proton and nucleon-proton data at lower and higher energies covering the medium- and large-vertical stroketvertical stroke region. Some prominent models and their predictions for elastic scattering at WA7 energies and beyond are reviewed, with emphasis on geometrical scaling, factorizing eikonal models, lowest-order QCD and other dynamical exchange-type models. Results for anti pp two-body annihilation into ..pi../sup -/..pi../sup +/ and K/sup -/K/sup +/ at 30 and 50 GeV/c, obtained in parallel with the elastic anti pp data, are also presented.
International Nuclear Information System (INIS)
Asa'd, Z.; Coupland, M.; Davis, D.G.; Duff, B.G.; Fearnley, T.; Heymann, F.F.; Imrie, D.C.; Lush, G.J.; Phillips, M.; Baglin, C.; Guillaud, J.P.; Poulet, M.; Myrheim, J.; Gjerpe, I.K.; Buran, T.; Buzzo, A.; Ferroni, S.; Gracco, V.; Kirsebom, K.; Macri, M.; Santroni, A.; Soersdal, T.
1985-01-01
Results are presented from experiment WA7 at the CERN SPS, which has measured the elastic differential cross sections of πsup(+-)p, Ksup(+-)p, anti pp and pp at incident momenta of 20, 30 and 50 GeV/c. The measurements cover the momentum transfer range 0.5 2 , corresponding to c.m. scattering angles between 10 0 and 50 0 . The experimental set-up, trigger logic and data analysis are described. The experimental results are compared with existing meson-proton and nucleon-proton data at lower and higher energies covering the medium- and large-vertical stroketvertical stroke region. Some prominent models and their predictions for elastic scattering at WA7 energies and beyond are reviewed, with emphasis on geometrical scaling, factorizing eikonal models, lowest-order QCD and other dynamical exchange-type models. Results for anti pp two-body annihilation into π - π + and K - K + at 30 and 50 GeV/c, obtained in parallel with the elastic anti pp data, are also presented. (orig.)
International Nuclear Information System (INIS)
Lapoux, V.
2005-09-01
Information on the structure, spectroscopy and target interaction potentials of exotic nuclei can be inferred by interpreting measured data from direct reactions on proton such as elastic or inelastic scattering of proton (p,p') or one-nucleon transfer reaction (p,d). A series of experimental results has been obtained at the GANIL facilities on the setting composed of the MUST telescope array used for the detection of light charged-particles and of CATS beam detectors. This setting aims at measuring reactions on light proton or deuteron targets through reverse kinematics. Particularly, results on C 10 , C 11 and on direct reactions with the He 8 beam of Spiral are presented. The first chapter is dedicated to the description of the most important theories concerning the nucleus. The experimental tools used to probe the nucleus are reported in the second chapter. The third and fourth chapters present the framework that has allowed us to analyse results from (p,p') and (p,d) reactions on weakly bound exotic nuclei. The last chapter is dedicated to the description of future experimental programs. (A.C.)
International Nuclear Information System (INIS)
Asa'd, Z.; Coupland, M.; Davis, D.G.; Duff, B.G.; Gjerpe, I.; Heymann, F.F.; Imrie, D.C.; Lowndes, R.; Lush, G.J.; Phillips, M.; Baglin, C.; Poulet, M.; Yvert, M.; Benso, S.; Buzzo, A.; Ferroni, S.; Gracco, V.; Macri, M.; Santroni, A.; Brobakken, K.; Bugge, L.; Buran, T.; Fearnley, T.; Helgaker, P.; Kirsebom, K.; Moe, A.; Soerensen, S.O.; Hansen, J.D.; Myrheim, J.; Skjevling, G.
1982-01-01
Measurements of the differential elastic cross sections for π - p scattering at incident momenta of 20 and 50 GeV/c and π + p at 50 GeV/c in the momentum transfer range 0.7 2 are presented. The data are compared with various models of elastic scattering. (orig.)
Elastic and inelastic scattering of polarized protons from carbon-12 at 400, 600, and 700 MeV
International Nuclear Information System (INIS)
Jones, K.W.
1984-04-01
Good resolution cross section and analyzing power (p vector, p') data for many states in 12 C up to an excitation energy of 21 MeV and spanning a momentum transfer range of 0.3 to 2.1 fm -1 were obtained using the High Resolution Spectrometer at the Clinton P. Anderson Meson Physics Facility at incident beam energies of 398, 597, and 698 MeV. Optical model potentials were obtained from the elastic scattering data. Inelastic data were analyzed in the Distorted Wave Impulse Approximation using the Love-Franey effective nucleon-nucleon interaction. The energy dependent isoscalar natural parity cross sections were underestimated, while phase difficulties were encountered in fitting analyzing powers. The energy independent isovector natural parity cross sections were reasonably reproduced, but analyzing powers were not, the calculations yielding positive trends whereas the data are of opposite sign. The energy independent isoscalar and isovector unnatural parity cross sections were quite well reproduced up to moderate momentum transfers, and striking successes were observed for some analyzing power data. Systematics of energy dependence together with the results of the DWIA calculations permitted the assignment of spin, parity and isospin quantum numbers to states in the 18-21 MeV excitation region. 64 references
International Nuclear Information System (INIS)
Kluit, P.M.
1988-01-01
The subject of this thesis is the experimental study of the elastic scattering of protons and anti-protons at a centre of mass energy of 546 GeV at the SPS (Super Proton Synchrotron) at CERN. The measurement of ρ, i.e. the ratio of the real to the imaginary part of the nuclear part of elastic scattering amplitude for proton-antiproton at zero momentum transfer squared (-t = 0 GeV 2 ), at a centre of mass energy of √s = 546 GeV is described. The implications of the result of this measurement for the behaviour of the total cross section in the TeV domain are derived. The hypothesis is investigated whether there is a relation between the rise of the total cross section and the rise of the total jet cross section, as calculated in perturbative QCD and observed by the UA1 experiment. 104 refs.; 40 figs.; 16 tabs
High energy proton-nucleus scattering
International Nuclear Information System (INIS)
Beurtey, R.M.
1977-01-01
This paper is restricted to an overall global criticism of what has been produced, experimentally and theoretically, during the past ten years, concerning elastic proton scattering at intermediate energy: theoretical models and approximations, phenomenological analysis, criticisms and suggestions on experimental methods
Proton nuclear scattering radiography
International Nuclear Information System (INIS)
Duchazeaubeneix, J.C.; Faivre, J.C.; Garreta, D.
1982-10-01
Nuclear scattering of protons allows to radiograph objects with specific properties: direct 3- dimensional radiography, different information as compared to X-ray technique, hydrogen radiography. Furthermore, it is a well adapted method to gating techniques allowing the radiography of fast periodic moving systems. Results obtained on different objects (light and heavy materials) are shown and discussed. The dose delivery is compatible with clinical use, but at the moment, the irradiation time is too long between 1 and 4 hours. Perspectives to make the radiography faster and to get a practical method are discussed
Intermediate energy proton scattering from 10B
International Nuclear Information System (INIS)
Lewis, P.R.; Shute, G.G.; Spicer, R.S.; Henderson, R.S.
1990-01-01
Differential cross sections have been measured for 200 MeV proton scattering from 10 B. Data for six low lying natural parity levels below 6 MeV excitation energy are presented. Distorted wave analysis using a density dependent nucleon-nucleon interaction has assessed model spectroscopies of these excited states. The significance of the contribution from quadrupole scattering to the elastic cross section is discussed. 49 refs., 5 tabs., 21 figs
Exclusive compton scattering on the proton
International Nuclear Information System (INIS)
Chen, J.P.; Chudakov, E.; DeJager, C.; Degtyarenko, P.; Ent, R.; Gomez, J.; Hansen, O.; Keppel, C.; Klein, F.; Kuss, M.
1999-01-01
An experiment is proposed to measure the cross sections for Real Compton Scattering from the proton in the energy range 3-6 GeV and over a wide angular range, and to measure the longitudinal and transverse components of the polarization transfer to the recoil proton at a single kinematic point. Together, these measurements will test models of the reaction mechanism and determine new structure functions of the proton that are related to the same non-forward parton densities that determine the elastic electron scattering form factors and the parton densities. The experiment utilizes an untagged Bremsstrahlung photon beam and the standard Hall A cryogenic targets. The scattered photon is detected in a photon spectrometer, currently under construction. The coincident recoil proton is detected in one of the Hall A magnetic spectrometers and its polarization components are measured in the existing Focal Plane Polarimeter. This proposal extends and supersedes E97 - 108 which was approved by PAC13. (author)
Exclusive compton scattering on the proton
Energy Technology Data Exchange (ETDEWEB)
Chen, J.P.; Chudakov, E.; DeJager, C.; Degtyarenko, P.; Ent, R.; Gomez, J.; Hansen, O.; Keppel, C.; Klein, F.; Kuss, M. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)] [and others
1999-07-01
An experiment is proposed to measure the cross sections for Real Compton Scattering from the proton in the energy range 3-6 GeV and over a wide angular range, and to measure the longitudinal and transverse components of the polarization transfer to the recoil proton at a single kinematic point. Together, these measurements will test models of the reaction mechanism and determine new structure functions of the proton that are related to the same non-forward parton densities that determine the elastic electron scattering form factors and the parton densities. The experiment utilizes an untagged Bremsstrahlung photon beam and the standard Hall A cryogenic targets. The scattered photon is detected in a photon spectrometer, currently under construction. The coincident recoil proton is detected in one of the Hall A magnetic spectrometers and its polarization components are measured in the existing Focal Plane Polarimeter. This proposal extends and supersedes E97 - 108 which was approved by PAC13. (author)
Exclusive Compton Scattering on the Proton
International Nuclear Information System (INIS)
Chen, J. P.; Chudakov, E.; DeJager, C.; Degtyarenko, P.; Ent, R.; Gomez, J.; Hansen, O.; Keppel, C.; Klein, F.; Kuss, M.; LeRose, J.; Liang, M.; Michaels, R.; Mitchell, J.; Liyanage, N.; Rutt, P.; Saha, A.; Wojtsekhowski, B.; Bouwhuis, M.; Chang, T.H.; Holt, R. J.; Nathan, A. M.; Roedelbronn, M.; Wijesooriya, K.; Williamson, S. E.; Dodge, G.; Hyde-Wright, C.; Radyushkin, A.; Sabatie, F.; Weinstein, L. B.; Ulmer, P.; Bosted, P.; Finn, J. M.; Jones, M.; Churchwell, S.; Howell, C.; Gilman, R.; Glashausser, C.; Jiang, X.; Ransome, R.; Strauch, S.; Berthot, J.; Bertin, P.; Fonvielle, H.; Roblin, Y.; Bertozzi, W.; Gilad, S.; Rowntree, D.; Zu, Z.; Brown, D.; Chang, G.; Afanasev, A.; Egiyan, K.; Hoohauneysan, E.; Ketikyan, A.; Mailyan, S.; Petrosyan, A.; Shahinyan, A.; Voskanyan, H.; Boeglin, W.; Markowitz, P.; Hines, J.; Strobel, G.; Templon, J.; Feldman, G.; Morris, C. L.; Gladyshev, V.; Lindgren, R. A.; Calarco, J.; Hersman, W.; Leuschner, M.; Gasparian, A.
1999-01-01
An experiment is proposed to measure the cross sections for Real Compton Scattering from the proton in the energy range 3-6 GeV and over a wide angular range; and to measure the longitudinal and transverse components of the polarization transfer to the recoil proton at a single kinematic point. Together; these measurements will test models of the reaction mechanism and determine new structure functions of the proton that are related to the same nonforward parton densities that determine the elastic electron scattering form factors and the parton densities. The experiment utilizes an untagged bremsstrahlung photon beam and the standard Hall A cryogenic targets. The scattered photon is detected in a photon spectrometer; currently under construction. The coincident recoil proton is detected in one of the Hall A magnetic spectrometers and its polarization components are measured in the existing Focal Plane Polarimeter. This proposal extends and supercedes E97-108 which was approved by PAC13
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
Energy Technology Data Exchange (ETDEWEB)
Laurat, M [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes
1969-07-01
A description is given of the experimental set-up which has been devised for carrying out spectrometric and absolute cross-section measurements on the reactions induced by protons accelerated in a 12 MeV Van de Graaff Tandem. The particles are detected by silicon junctions; the weight of the targets (about ten {mu}g/cm{sup 2}) is determined by the quartz method. The experimental equipment has been controlled by a study of proton scattering by lithium-6, and has made it possible to evaluate the elastic and inelastic scattering (1. level excitation) by lithium 7 of 2 to 9 MeV protons. The most probable spin and parity values for the six levels of {sup 8}Be between 19 and 25 MeV excitation energy have been determined from a knowledge of the observed structure. (author) [French] Nous decrivons le dispositif experimental mis au point pour effectuer les mesures de spectrometrie et de section efficace absolue pour les reactions induites par des protons acceleres par un Van de Graaff Tandem 12 MeV. Les particules sont detectees par des jonctions au silicium, le poids des cibles (de l'ordre d'une dizaine de {mu}g/cm{sup 2}), mesure par la methode du quartz. L'ensemble de l'appareillage a ete controle par l'etude de la diffusion des protons par le lithium 6, et nous a permis de preciser les diffusions elastiques et inelastiques (excitation du 1er niveau) des protons de 2 a 9 MeV par le lithium 7. La structure observee a permis de determiner les spin et parite les plus probables de six niveaux du {sup 8}Be entre 19 et 25 MeV d'energie d'excitation. (auteur)
Energy Technology Data Exchange (ETDEWEB)
Laurat, M. [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes
1969-07-01
A description is given of the experimental set-up which has been devised for carrying out spectrometric and absolute cross-section measurements on the reactions induced by protons accelerated in a 12 MeV Van de Graaff Tandem. The particles are detected by silicon junctions; the weight of the targets (about ten {mu}g/cm{sup 2}) is determined by the quartz method. The experimental equipment has been controlled by a study of proton scattering by lithium-6, and has made it possible to evaluate the elastic and inelastic scattering (1. level excitation) by lithium 7 of 2 to 9 MeV protons. The most probable spin and parity values for the six levels of {sup 8}Be between 19 and 25 MeV excitation energy have been determined from a knowledge of the observed structure. (author) [French] Nous decrivons le dispositif experimental mis au point pour effectuer les mesures de spectrometrie et de section efficace absolue pour les reactions induites par des protons acceleres par un Van de Graaff Tandem 12 MeV. Les particules sont detectees par des jonctions au silicium, le poids des cibles (de l'ordre d'une dizaine de {mu}g/cm{sup 2}), mesure par la methode du quartz. L'ensemble de l'appareillage a ete controle par l'etude de la diffusion des protons par le lithium 6, et nous a permis de preciser les diffusions elastiques et inelastiques (excitation du 1er niveau) des protons de 2 a 9 MeV par le lithium 7. La structure observee a permis de determiner les spin et parite les plus probables de six niveaux du {sup 8}Be entre 19 et 25 MeV d'energie d'excitation. (auteur)
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...
Proton scattering at intermediate energies
International Nuclear Information System (INIS)
Chaumeaux, A.; Layly, V.; Schaeffer, R.
1977-01-01
This article is devoted to the analysis of the most recent Saclay data of elastic and inelastic proton scattering on nuclei at incident energies around 1GeV ( 16 O, the Ca isotopes, the Ni isotopes, 90 Zr and 208 Pb). Various theories (Impulse or Glauber approximation) are comapred. It is shown that the reaction mechanism is very well understood at 1GeV and that, at these energies, absorption and distortion is small enough, so one can extract nuclear densities from the experiment. In particular, the shape of the neutron densities is given, and compared to the Hartree-Fock predictions. The uncertainties, especially in the determination of the neutron radii are discussed [fr
Energy Technology Data Exchange (ETDEWEB)
Unamuno, S
1965-07-01
This paper presents the results-obtained in studying the two-prong interactions observed in the Saclay 81 cm hydrogen bubble chamber exposed to the 3.0 and 4.0 GeV/c antiproton beams from CERN Proton-Synchroton. Total elastic cross-sections corresponding to both energies are given. The results are given. The results are compared with those of p-p scaterring at different energies and with those of p-p scattering. Several optical-models, from the simples one (the black disk model) to a rather elaborated, four-parameters model have been applied. These models can explain some of the experimental results but fail in predicting the angular distribution of large angle scattering. (Author)
Scattering of intermediate energy protons
International Nuclear Information System (INIS)
Chaumeaux, Alain.
1980-06-01
The scattering of 1 GeV protons appears to be a powerful means of investigating nuclear matter. We worked with SPESI and the formalism of Kerman-Mc Manus and Thaler. The amplitude of nucleon-nucleon scattering was studied as were the aspects of 1 GeV proton scattering (multiple scattering, absorption, spin-orbit coupling, N-N amplitude, KMT-Glauber comparison, second order effects). The results of proton scattering on 16 O, the isotopes of calcium, 58 Ni, 90 Zr and 208 Pb are given [fr
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)
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
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.
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)
Spin observables in proton-neutron scattering at intermediate energy
International Nuclear Information System (INIS)
Spinka, H.
1986-05-01
A summary of np elastic scattering spin measurements at intermediate energy is given. Preliminary results from a LAMPF experiment to measure free neutron-proton elastic scattering spin-spin correlation parameters are presented. A longitudinally polarized proton target was used. These measurements are part of a program to determine the neutron-proton amplitudes in a model independent fashion at 500, 650, and 800 MeV. Some new proton-proton total cross sections in pure helicity states (Δσ/sub L/(pp)) near 3 GeV/c are also given. 37 refs., 2 figs
Quasi elastic scattering of 600 MeV protons by alpha clusters in light and medium nuclei
International Nuclear Information System (INIS)
Landaud, G.; Devaux, A.; Delpierre, P.; Kahane, J.; Sene, R.; Yonnet, J.; Anne, R.
1977-06-01
Knockout of α-clusters from light and medium weight nuclei by 600 MeV protons has been investigated. The outgoing protons and α-particles were detected in coincidence; their momenta were measured with two large magnetic spectrometers with proportional wire chambers. Experimental methods used to work with a high beam rate and an efficient proton rejection in the α-arm are described. Separation energy spectra are given for 6 Li, 7 Li, 12 C, 24 Mg, 27 Al and 40 Ca nuclei. A peak is observed at an excited energy equal to zero, except for the 27 Al target
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 ...
Theoretically unprejudiced fits to proton scattering
International Nuclear Information System (INIS)
Kobos, A.M.; Mackintosh, R.S.
1979-01-01
By using a spline interpolation method applied to all components of the proton optical potential we have fitted elastic scattering from 40 Ca and from 16 O at a range of energies. The potentials are highly oscillatory and we have shown that similar oscillations are found when the spline fitting procedure is applied to pseudo-data generated from potentials of known l-dependence. Moreover, we show how to find an l-independent potential equivalent to one that is l-dependent and we find that it is oscillatory and that various characteristic features of empirical spline fit potentials can be explained. Thus, by fitting the data with model indenpendt l-independent potentials we have found support for the contention that the nucleon optical potential should be viewed as being l-dependent. This work may be regarded as an example of the kind of physical information that can be gained by pursuing exact fits to proton elastic scattering data
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)
Simultaneous and sequential transfer of proton and alpha-particle in the elastic 11B+16O scattering
International Nuclear Information System (INIS)
Kamys, B.; Rudy, Z.; Kisiel, J.; Kwasniewicsz, E.; Wolter, H.H.
1992-01-01
We have developed a method to treat multi-nucleon transfer as the transfer of two - possible different - subclusters, as e.g. with ' 5 Li'=(α,p). As a consequence we take into account two reaction mechanisms, the one-step simultaneous and the two-step sequential transfer of the two clusters. We formulate the method of calculation of the simultaneous transfer form factor for two non-identifical particles and also of the two-cluster spectroscopic amplitudes from shell model wave functions. We apply the method to the elastic transfer reaction 11 B( 16 O, 11 B) 11 O together with the single α and p transfer reaction 11 B( 16 O, 15 N) 12 C for E lab between 30 and 60 MeV. We obtain a consistently good description of all the data by reasonable adjustment of the spectroscopic amplitudes. In particular we find that the simultaneous (αp) transfer is considerably more important than the sequential transfer indicating strong five-nucleon correlations in these light nuclei. (orig.)
Elastic scattering of polarized protons by 20Ne between 4.5 Mev and 5.5 Mev
International Nuclear Information System (INIS)
Avila A, O.L.
1979-01-01
Starting with the study of 20 Ne(p,p) 20 nuclear reaction, we obtained information about the nuclear structure of 21 Na. The experiment was made at Notre Dame University; a target of 20 Ne was bombarded with polarized protons, changing the incident energy of them between 4.5 Mev and 5.5 Mev at intervals of 10 keV. Fourteen detectors were set covering angles from 35 degrees until 165 degrees, with intervals of 10 degrees each. In this form measurements for computing polarization and differential sections were obtained, with them an analysis of runnings of phase was made, and the parameters associated with two of the excited levels of the composed formed nucleous 21 Na, that are viewed as resonances in the section were settled; those resonances correspond to a level Psub(3/2) of energy excitation 6.877, a total width of 36 keV, and a level Fsub(7/2) of energy excitation 6.992 and total width of 48 keV. I hope that these results will be part of a set of values that will be utilized in order to confront them with the existent nuclear models. (author)
Energy Technology Data Exchange (ETDEWEB)
Fukada, Noboru; Imura, Takeshi; Hiraki, Akio [Osaka Univ., Suita (Japan). Faculty of Engineering; Itahashi, Takahisa; Fukuda, Tomokazu; Tanaka, Masayoshi
1982-09-01
We have drastically improved the sensitivity of the nuclear elastic scattering (NES) method for determining hydrogen concentrations in hydrogenated amorphous silicon (a-Si:H) films. A beam of 100 MeV /sup 3/He/sup 2 +/ ions was used in the experiment. By taking the coincidence of detection of the scattered /sup 3/He ion with that of the recoil proton, we could achieve a sensitivity of 0.1 atomic percent with a precision of about 1 percent for 1 ..mu..m films.
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.
Energy Technology Data Exchange (ETDEWEB)
Sadeghi, A
1966-07-01
The results of absolute measurements of cross sections for the scattering of protons by {sup 12}C to the two first excited levels are given. The measurements were made from 4.6 to 11.4 MeV at 17 angles for (p,p) and at 15 angles for (p,p') (1. excited level) as well as 8 angles for (p,p'') (2. excited level). A gaseous target with differential pumping was used. The elastic scattering was analyzed using the R-matrix theory with the optical model. Then a new analysis of both (p,p) and (p,p') was achieved using the coupled-wave formalism. The information on the levels of the compound nucleus was completed and was confirmed. (author) [French] Cette these rapporte le resultat de mesures absolues des sections efficaces de diffusion p,p et pp' (conduisant aux deux premiers niveaux excites) de protons par '1'2C. Ces mesures ont ete faites de 4,6 a 11,4 MeV, a 17 angles pour (p,p), a 15 angles pour pp' (1er niveau excite) et a 8 angles pour pp'' (2eme niveau excite). Une chambre a cible gazeuse avec pompage differentiel a ete utilisee. La diffusion elastique a ete analysee au moyen de la theorie de la matrice R avec modele optique pour (p,p). Cette analyse a ete reprise en meme temps que celle de la diffusion inelastique par l'emploi d'equations couplees. Les resultats anterieurs sur les niveaux du noyau compose ont ete confirmes et completes. (auteur)
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.)
Energy Technology Data Exchange (ETDEWEB)
Ilieva, Stoyanka
2008-07-01
In the current experiment, the differential cross sections for proton elastic scattering on the isotopes {sup 7,9,10,11,12,14}Be and {sup 8}B were measured. As results from the experiment, the absolute differential cross sections d{sigma}/dt as a function of the four momentum transfer t were obtained. In this work the differential cross sections for elastic p-{sup 12}Be, p-{sup 14}Be and p-{sup 8}B scattering at low t (t{<=}0.05(GeV/c){sup 2}) are presented. The measured cross sections were analyzed within the Glauber multiple-scattering theory using different density parameterizations, and the nuclear matter density distributions and radii of the investigated isotopes were determined. The determined rms matter radius is 3.11{+-}0.04{+-}0.13 fm. In the case of the {sup 12}Be nucleus the results showed an extended matter distribution as well. For this nucleus a matter radius of 2.82{+-}0.03{+-}0.12 fm was determined. An interesting result is that the free {sup 12}Be nucleus behaves differently from the core of {sup 14}Be and is much more extended than it. Preliminary experimental results for the isotope {sup 8}B are also presented. An extended matter distribution was obtained (though much more compact as compared to the neutron halos). A proton halo structure was observed for the first time with the proton elastic scattering method. The deduced matter radius is 2.60{+-}0.02{+-}0.26 fm. Results from the feasibility studies of the EXL detector setup, performed at the present ESR storage ring, are presented. (orig.)
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.)
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
Proton-proton bremsstrahlung towards the elastic limit
Mahjour-Shafiei, M.; Amir-Ahmadi, H. R.; Bacelar, J. C. S.; Castelijns, R.; Ermisch, K.; van Garderen, E.; Gašparić, I.; Harakeh, M. N.; Kalantar-Nayestanaki, N.; Kiš, M.; Löhner, H.
2005-05-01
In oder to study proton-proton bremsstrahlung moving towards the elastic limit, a detection system, consisting of Plastic-ball and SALAD, was set up and an experiment at 190 MeV incident beam energy was performed. Here, the experimental setup and the data analysis procedure along with some results obtained in the measurement are discussed.
Proton-proton bremsstrahlung towards the elastic limit
International Nuclear Information System (INIS)
Mahjour-Shafiei, M.; Amir-Ahmadi, H.R.; Bacelar, J.C.S.; Castelijns, R.; Ermisch, K.; Garderen, E. van; Harakeh, M.N.; Kalantar-Nayestanaki, N.; Kis, M.; Loehner, H.; Gasparic, I.
2005-01-01
In oder to study proton-proton bremsstrahlung moving towards the elastic limit, a detection system, consisting of Plastic-ball and SALAD, was set up and an experiment at 190 MeV incident beam energy was performed. Here, the experimental setup and the data analysis procedure along with some results obtained in the measurement are discussed
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
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
Energy Technology Data Exchange (ETDEWEB)
Duflo, J. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1969-07-01
Backward elastic K{sup +}p and K{sup -}p scattering has been measured in the angular interval 168 deg. < {theta}.c.m. < 177 deg. The experimental apparatus included optical spark chambers to measure the three prongs of the event scattering, a set of scintillation counters and Cerenkov counters to select events ant trigger chambers, and a magnet to determine the moment of the recoil proton. 106000 photographs was taken. Of these, 22 satisfied all requirements as elastic K{sup +}p scattering events. No event was found satisfy the kinematical criteria for K{sup -}p elastic scattering. The correspondent values of differential cross sections are: (d{sigma}/d{omega})K{sup +}p {yields} pK{sup +} = 17 {+-} 4 {mu}b/ster. (d{sigma}/d{omega})K{sup -}p {yields} pK{sup -} {<=} 0.6 {mu}b/ster. Contaminations by {pi}p backward scattering, and inelastic scattering were estimated. Elastic scattering K{sup +}p exhibits a backward peak. A reasonably satisfactory interpretation of our results is obtained by exchange models. There is, in fact, no definitely established particles which could intermediate the Kp{sup -} {yields} pK{sup -} process in exchange cannel. That is in good agreement with our small value of K{sup -}p backward elastic scattering cross section. Our results lend support to the conclusions of the interference model developed by Barger and Cline for the {pi}p backward scattering, and to qualitative previsions of the Quark models. (author) [French] La diffusion elastique en arriere des K{sup +} et K{sup -} par les protons a ete mesuree dans l'intervalle angulaire 168 deg. < {theta}cm < 177 deg. Le dispositif experimental comprenait des chambres a etincelles 'optiques' pour mesurer les trois trajectoires de l'evenement diffuse, un ensemble de compteurs a scintillations et de compteurs Cerenkov pour selectionner les evenements et declencher les chambres, et un aimant pour determiner le moment du proton de recul. 106000 photographies ont ete prises
Energy Technology Data Exchange (ETDEWEB)
Duflo, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1969-07-01
Backward elastic K{sup +}p and K{sup -}p scattering has been measured in the angular interval 168 deg. < {theta}.c.m. < 177 deg. The experimental apparatus included optical spark chambers to measure the three prongs of the event scattering, a set of scintillation counters and Cerenkov counters to select events ant trigger chambers, and a magnet to determine the moment of the recoil proton. 106000 photographs was taken. Of these, 22 satisfied all requirements as elastic K{sup +}p scattering events. No event was found satisfy the kinematical criteria for K{sup -}p elastic scattering. The correspondent values of differential cross sections are: (d{sigma}/d{omega})K{sup +}p {yields} pK{sup +} = 17 {+-} 4 {mu}b/ster. (d{sigma}/d{omega})K{sup -}p {yields} pK{sup -} {<=} 0.6 {mu}b/ster. Contaminations by {pi}p backward scattering, and inelastic scattering were estimated. Elastic scattering K{sup +}p exhibits a backward peak. A reasonably satisfactory interpretation of our results is obtained by exchange models. There is, in fact, no definitely established particles which could intermediate the Kp{sup -} {yields} pK{sup -} process in exchange cannel. That is in good agreement with our small value of K{sup -}p backward elastic scattering cross section. Our results lend support to the conclusions of the interference model developed by Barger and Cline for the {pi}p backward scattering, and to qualitative previsions of the Quark models. (author) [French] La diffusion elastique en arriere des K{sup +} et K{sup -} par les protons a ete mesuree dans l'intervalle angulaire 168 deg. < {theta}cm < 177 deg. Le dispositif experimental comprenait des chambres a etincelles 'optiques' pour mesurer les trois trajectoires de l'evenement diffuse, un ensemble de compteurs a scintillations et de compteurs Cerenkov pour selectionner les evenements et declencher les chambres, et un aimant pour determiner le moment du proton de recul. 106000 photographies ont ete prises, dont 22 ont satisfait a
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
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
Antiproton-Proton Glory Scattering
2002-01-01
This experiment measures @*p and K|-p backwards scattering between 8 and 16 GeV/c in the Omega spectrometer using the S1 beam, with sensitivities of several events per nanobarn. The mechanism responsible for backward scattering in channels not mediated by particle exchange is not understood, and could be almost energy-independent glory scattering, especially since relatively high cross sections of 190~(@*p) and 120~(K|-p)nb have been measured earlier at 5~GeV/c. @p|-p backwards scattering is measured for monitoring purposes. The trigger requires a forward particle of momentum close to the beam momentum. Absence of light in the two forward Cerenkov counters indicates that the particle is a proton. Combinations of an incident @p|- and an outgoing K|+, or an incident K|- or @* and an outgoing @p|+, cover the following byproducts: @*p~@A~@p|+@p|- which is an (allowed) baryon exchange reaction, and the exotic exchange reactions @p|-p~@A~K|+Y K|-p~@A~@p|+Y|-, where Y|- may be the @S|- or the Y*|-(1385).
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.
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
International Nuclear Information System (INIS)
Aksouh, F.
2002-12-01
The elastic proton scattering from the halo nuclei 6 He and 8 He was investigated in inverse kinematics at energies around 700 MeV/u with the aim to deduce the differential cross sections for the region of high momentum transfer, covering the first diffraction minimum. For this purpose, a liquid-hydrogen target was specially developed and used for the first time allowing to obtain low-background data as compared to commonly used targets made from C-H compounds. Previous data taken in the region of small momentum transfer were sensitive to the size and the peripheral shape of the total nuclear matter density distribution but not to the inner part. The present data allow for a more detailed insight in the structure of the alike core in 6,8 He through a better determination of the matter density distributions. Several density distributions calculated from different microscopic models were used to derive elastic scattering cross sections which are compared with the obtained data. (author)
Qattan, I. A.; Homouz, D.; Riahi, M. K.
2018-04-01
In this work, we improve on and extend to low- and high-Q2 values the extractions of the two-photon-exchange (TPE) amplitudes and the ratio Pl/PlBorn(ɛ ,Q2) using world data on electron-proton elastic scattering cross section σR(ɛ ,Q2) with an emphasis on data covering the high-momentum region, up to Q2=5.20 (GeV/c ) 2 , to better constrain the TPE amplitudes in this region. We provide a new parametrization of the TPE amplitudes, along with an estimate of the fit uncertainties. We compare the results to several previous phenomenological extractions and hadronic TPE predictions. We use the new parametrization of the TPE amplitudes to extract the ratio Pl/PlBorn(ɛ ,Q2) , and then compare the results to previous extractions, several theoretical calculations, and direct measurements at Q2=2.50 (GeV/c ) 2 .
International Nuclear Information System (INIS)
Ottenstein, N.; Wallace, S.J.; Tjon, J.A.
1987-11-01
Dirac impulse approximation predictions for cross sections and spin observables in elastic proton scattering by 40 Ca and 208 Pb at energies of 200, 500 and 800 MeV are presented. The analysis is based on complete sets of Lorentz invariant NN amplitudes determined from a meson exchange model of the nuclear force. Effects of relativistic nuclear densities are explored including estimates of the vacuum polarization corrections based on quantum hadrodynamics. Effects of Pauli blocking are considered using the approximations of Murdock and Horowitz. A good description of the experimental data is obtained over a broad energy range and over a wide variation of nuclear size based on the generalized impulse approximation. Vacuum polarization corrections are found to enhance the agreement between theory and experiment. 18 refs., 8 figs
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.)
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.
Aspects of the fundamental theory of proton-proton scattering
Martin, A
1973-01-01
After recalling the existence of a high energy bound on proton-proton total cross-sections, the author discusses the various phenomena which occur when these cross-sections rise and especially when they have the qualitative behaviour of the bound: rising elastic cross- sections, shrinking diffraction peak, validity of the Pomeranchuk theorem for total and elastic cross-sections, existence of a positive real part of the forward amplitude at high energies. (16 refs).
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 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
Energy Technology Data Exchange (ETDEWEB)
Jardillier, Johann [Lab. de Physique Corpusculaire, Clermont-Ferrand-2 Univ., 63 - Aubiere (France)
1999-09-21
In the quark model, the proton is described as a system of three quarks UUD. However, recent experiments (CERN, SLAC) have shown that the strange quarks may contribute in a significant way to the mass and the spin of the proton. The HAPPEX experiment gives one further knowledge about the question of the role the strange quarks play inside the proton. It measures parity violating asymmetry in the scattering of polarized electrons from a proton because the latter is sensitive to the contribution of the strange quarks to the electromagnetic form factors of the nucleon. The observed asymmetry is in the order of a few ppm (part per million). The main difficulty of the experiment is to identify, to estimate and to minimize, as much as possible, all the systematic effects which could give rise to false asymmetries. This thesis discusses the principle of the HAPPEX experiment, its implementation at the Jefferson Lab (JLab), the processing and the analysis of the data, the systematic errors, and finally presents the result of the first data taking (1999) and its present interpretation. The HAPPEX experiment has measured, at Q{sup 2} = 0.5 (GeV/c){sup 2}, a strange quarks contribution of (1.0 {+-} 2.3)% to the electromagnetic form factors of the nucleon. The statistics and the systematic effects (measure of the electron beam polarization and knowledge of the neutron electric form factor) contribute equally to the error. (author)
Impact parameter analysis of proton-proton elastic and inelastic interactions at 360 GeV/c
International Nuclear Information System (INIS)
Banerjee, S.; Ragavan, R.; Bailly, J
1987-01-01
Data obtained with the European Hybrid Spectrometer on the proton-proton elastic scattering at 360 GeV/c are presented. The differential cross sections of elastic and inelastic pp-interactions are studied as a function of the impact parameter. The results are compared to those obtained at other energies. They are interpreted in the framework of a simple geometrical Monte-Carlo model of inelastic collisions considering protons as composite particles having a definite effective radius with valence quarks inside. The shape of the inelastic overlap function is well reproduced for both pp- and π + p-interactions. The effective radii of the proton and pion as well as of the valence quarks are estimated for inelastic interactions. The model calculations indicate an increase of the effective radii both of protons and valence quarks and an increase of the proton opacity with increasing energy
MUSE: Measuring the proton radius with muon-proton scattering
Energy Technology Data Exchange (ETDEWEB)
Bernauer, Jan Christopher [Massachusetts Institute of Technology, Cambridge (United States)
2014-07-01
The proton radius has been measured so far using electron-proton scattering, electronic Hydrogen spectroscopy and muonic Hydrogen spectroscopy, the latter producing a much more accurate, but seven sigma different, result, leading to the now famous proton radius puzzle. The MUSE collaboration aims to complete the set of measurements by using muon scattering to determine the proton radius and to shed light on possible explanations of the discrepancy. The talk gives an overview of the experiment motivation and design and a status report on the progress.
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...
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
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 ...
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)
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.)
Neutron scattering from polarised proton domains
Van den Brandt, B; Kohbrecher, J; Konter, J A; Mango, S; Glattli, H; Leymarie, E; Grillo, I; May, R P; Jouve, H; Stuhrmann, H B; Stuhrmann, H B; Zimmer, O
2002-01-01
Time-dependent small-angle polarised neutron scattering from domains of polarised protons has been observed at the onset of dynamic nuclear polarisation in a frozen solution of 98% deuterated glycerol-water at 1 K containing a small concentration of paramagnetic centres (EHBA-Cr sup V). Simultaneous NMR measurements show that the observed scattering arises from protons around the Cr sup V -ions which are polarised to approx 10% in a few seconds, much faster than the protons in the bulk. (authors)
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
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.)
High-energy proton scattering on nuclei
Klovning, A; Schlüpmann, K
1973-01-01
High-energy proton scattering on Be, C, Cu and Pb targets is studied using a single-arm spectrometer. The projectile momenta were 19 and 24 GeV/c, the square of the four-momentum transfer varied from t=0.1 to t =4.4 GeV/sup 2/. Momentum distributions of scattered protons are recorded in the high-momentum range. An application of multiple- scattering theory yielded agreement of calculation and experimental results to within a +or-30% uncertainty of the former. (15 refs).
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
Proton optical potential and scattering matrix for tin nuclei at sub-coulomb energies
International Nuclear Information System (INIS)
Guzhovskij, B.Ya.; Dzyuba, B.M.
1981-01-01
A unified set of parameters of the proton optical potential (OP) for the n nuclei is searched for in the below-Coulomb-barrier energy range. The set must describe well the experimental data on the pn-reaction total cross sections and on the angular distributions of elastically scattered protons at E [ru
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.
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
Czech Academy of Sciences Publication Activity Database
Antchev, G.; Aspell, P.; Atanassov, I.; Kašpar, Jan; Kopal, Josef; Kundrát, Vojtěch; Lokajíček, Miloš V.; Procházka, Jiří
2015-01-01
Roč. 899, Oct (2015), s. 527-546 ISSN 0550-3213 R&D Projects: GA MŠk(CZ) LG13031 Institutional support: RVO:68378271 Keywords : elastic proton-proton scattering Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 3.735, year: 2015
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.
Transverse Imaging of the Proton in Exclusive Diffractive pp Scattering
International Nuclear Information System (INIS)
Christian Weiss; Leonid Frankfurt; Charles Hyde-Wright; Mark Strikman
2006-01-01
In a forthcoming paper we describe a new approach to rapidity gap survival (RGS) in the production of high-mass systems (H = dijet, Higgs, etc.) in exclusive double-gap diffractive pp scattering, pp -> p + H + p. It is based on the idea that hard and soft interactions are approximately independent (QCD factorization), and allows us to calculate the RGS probability in a model-independent way in terms of the gluon generalized parton distributions (GPDs) in the colliding protons and the pp elastic scattering amplitude. Here we focus on the transverse momentum dependence of the cross section. By measuring the ''diffraction pattern'', one can perform detailed tests of the interplay of hard and soft interactions, and even extract information about the gluon GPD in the proton from the data
Proton scattering from unstable nuclei
Indian Academy of Sciences (India)
The quality of the data obtained are illustrated with recent results obtained at the ... novel manifestations of nuclear structure should be uncovered, among which ..... Figure 6. 53 MeV/A øº. S elastic and inelastic angular distributions for the 2·.
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).
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.
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
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
Energy Technology Data Exchange (ETDEWEB)
Lapoux, V
2005-09-15
Information on the structure, spectroscopy and target interaction potentials of exotic nuclei can be inferred by interpreting measured data from direct reactions on proton such as elastic or inelastic scattering of proton (p,p') or one-nucleon transfer reaction (p,d). A series of experimental results has been obtained at the GANIL facilities on the setting composed of the MUST telescope array used for the detection of light charged-particles and of CATS beam detectors. This setting aims at measuring reactions on light proton or deuteron targets through reverse kinematics. Particularly, results on C{sup 10}, C{sup 11} and on direct reactions with the He{sup 8} beam of Spiral are presented. The first chapter is dedicated to the description of the most important theories concerning the nucleus. The experimental tools used to probe the nucleus are reported in the second chapter. The third and fourth chapters present the framework that has allowed us to analyse results from (p,p') and (p,d) reactions on weakly bound exotic nuclei. The last chapter is dedicated to the description of future experimental programs. (A.C.)
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
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)
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.
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
Radiative pion-proton scattering
International Nuclear Information System (INIS)
Ho-Kim, Q.; Lavine, J.P.
1977-01-01
The results are presented of a non-relativistic calculation of the π +- proton bremsstrahlung cross section at the pion kinetic energy of 298 MeV for backward photon angles. The pion-nucleon interaction is given by models that are based on the p-wave Chew-Low theory. An interaction current is included in an attempt to make the overall bremsstrahlung amplitude gauge-invariant. The predicted cross sections show little of the expected resonance, and are in fair agreement with the data. The authors have also calculated the cross sections at other kinetic energies, and have studied effects of the off-mass-shell electromagnetic vertex. (Auth.)
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
Quasi-elastic cross sections for 1GeV proton incident on {sup 4}He and {sup 12}C
Energy Technology Data Exchange (ETDEWEB)
Nishimura, M.; Nakamoto, T.; Shigyo, N. [Kyushu Univ., Fukuoka (Japan). Faculty of Engineering] [and others
1997-03-01
The experiment of p-n quasi-elastic scattering cross sections was carried out for 1GeV protons on {sup 4}He and {sup 12}C. The coincident measurement was made at c.m. angles of {+-} 90deg. The experiment was simulated by the use of HETC (High Energy Transport Code). It was examined to apply the p-n quasi-elastic scattering cross sections to neutron flux measurement. (author)
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
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
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
Inelastic proton scattering at medium energy
International Nuclear Information System (INIS)
Love, W.G.
1980-01-01
Some of the most essential characteristics of the nucleon-nucleon interaction for probing nuclear structure at bombarding energies between 100 and 800 MeV are considered. With a local representation of the on-shell N-N t-matrix, data for a variety of specific transitions at IUCF and LAMPF energies are discussed with an emphasis on the nuclear structure information sampled by proton scattering. The importance of incorporating constraints on nuclear structure imposed by electron scattering is stressed. Some rather unique aspects of the (p,n) reaction at intermediate energies are discussed in terms of its energy dependence and nuclear structure sum rules. 11 figures
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.
Asymmetry in π-p↑ elastic scattering in momentum range 1.4-2.1 GeV/c
International Nuclear Information System (INIS)
Alekseev, I.G.; Budkovskij, P.E.; Kanavets, V.P.
1989-01-01
Results of systematic measurements of the asymmetry parameter in the elastic scattering of pions on polarized protons at 1.4-2.1 GeV/c in the back hemisphere are presented together with a test of the isospin invariance of the data set available on pion-proton scattering in the investigated momentum range. The obtained data and amplitude reconstruction results are compared with the current phase shift analysis predictions. 22 refs.; 10 figs
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
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.)
Elastic neutron-proton differential cross section at 647 MeV
International Nuclear Information System (INIS)
Evans, M.L.
1979-04-01
The differential cross section for n-p elastic scattering in the angular range 51 0 was measured with high statistical accuracy using the 647 MeV monoenergetic neutron beam of the Los Alamos Meson Physics Facility. A proton recoil magnetic spectrometer was used for momentum analysis of the charge exchange protons from the reaction n+p→p+n. Absolute normalization of the cross section was established to within 7% using existing cross section data for the reaction p+p→π + +d. The results differ significantly from previous Dubna and PPA cross sections but agree well with recent Saclay data except at extreme backward angles. 41 references
Measurements of electron-proton elastic cross sections for 0.4 2 2
International Nuclear Information System (INIS)
Christy, M.E.; Ahmidouch, Abdellah; Armstrong, Christopher; Arrington, John; Razmik Asaturyan; Steven Avery; Baker, O.; Douglas Beck; Henk Blok; Bochna, C.W.; Werner Boeglin; Peter Bosted; Maurice Bouwhuis; Herbert Breuer; Brown, D.S.; Antje Bruell; Roger Carlini; Nicholas Chant; Anthony Cochran; Leon Cole; Samuel Danagoulian; Donal Day; James Dunne; Dipangkar Dutta; Rolf Ent; Howard Fenker; Fox, B.; Liping Gan; Haiyan Gao; Kenneth Garrow; David Gaskell; Ashot Gasparian; Don Geesaman; Paul Gueye; Mark Harvey; Roy Holt; Xiaodong Jiang; Cynthia Keppel; Edward Kinney; Yongguang Liang; Wolfgang Lorenzon; Allison Lung; Pete Markowitz; Martin, J.W.; Kevin McIlhany; Daniella Mckee; David Meekins; Miller, J.W.; Richard Milner; Joseph Mitchell; Hamlet Mkrtchyan; Robert Mueller; Alan Nathan; Gabriel Niculescu; Maria-Ioana Niculescu; Thomas O'neill; Vassilios Papavassiliou; Stephen Pate; Buz Piercey; David Potterveld; Ronald Ransome; Joerg Reinhold; Rollinde, E.; Philip Roos; Adam Sarty; Reyad Sawafta; Elaine Schulte; Edwin Segbefia; Smith, C.; Stepan Stepanyan; Steffen Strauch; Vardan Tadevosyan; Liguang Tang; Raphael Tieulent; Alicia Uzzle; William Vulcan; Stephen Wood; Feng Xiong; Lulin Yuan; Markus Zeier; Benedikt Zihlmann; Vitaliy Ziskin
2004-01-01
We report on precision measurements of the elastic cross section for electron-proton scattering performed in Hall C at Jefferson Lab. The measurements were made at 28 unique kinematic settings covering a range in momentum transfer of 0.4 2 2 . These measurements represent a significant contribution to the world's cross section data set in the Q 2 range where a large discrepancy currently exists between the ratio of electric to magnetic proton form factors extracted from previous cross section measurements and that recently measured via polarization transfer in Hall A at Jefferson Lab
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.
Why the Real Part of the Proton-Proton Forward Scattering Amplitude Should be Measured at the LHC
Bourrely, C.; Martin, Andre; Soffer, Jacques; Wu, Tai Tsun
2006-01-01
For the energy of 14 TeV, to be reached at the Large Hadron Collider (LHC), we have had for some time accurate predictions for both the real and imaginary parts of the forward proton-proton elastic scattering amplitude. LHC is now scheduled to start operating in two years, and it is timely to discuss some of the important consequences of the measurements of both the total cross-section and the ratio of the real to the imaginary part. We stress the importance of measuring the real part of the proton-proton forward scattering amplitude at LHC, because a deviation from existing theoretical predictions could be a strong sign for new physics.
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.
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)
International Nuclear Information System (INIS)
Haji-Saeid, S.M.
1980-01-01
Large deuteron vector and tensor asymmetries have been measured for the first time at intermediate energies. The polarized deuteron beam whose tensor and vector components were 0.75 and 0.25, respectively, were used at energies of 2.0, 1.6 and 1.2 GeV. The tensor and vector quantities Pyy and Py were extracted from the data obtained within beam polarization normal to the scattering plane, and Pxx was obtained when the polarization was precessed into the scattering plane. Analysis of the data using multiple scattering theory demonstrates the importance of the non-eikonal correction to the Glauber Model and also the sensitivity of the data to double-spin flip components of the NN amplitudes. In another experiment the differential cross section for the 12C(P,P')12C*(15.11 MeV, 1 + T = 1) reaction has been measured at 800 MeV; the range of the angular distribution corresponds to momentum transfers of 0.7 to 2.4 fm -1 (1 to 3.3 mπ). The cross section decreases almost exponentially at large angles; no maximum is observed in the region where nuclear critical opalescence might be expected. The cross sections which measured in parallel to the 15.11 MeV state were for the levels at 11.83 (2 - ), 12.71 (1 + ), 13.35 (2 - ), 16.1 (2 + ) and 16.58 (2 - ) MeV
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
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.
Study of elastic ρ0 photoproduction at HERA using the ZEUS leading proton spectrometer
International Nuclear Information System (INIS)
Derrick, M.; Krakauer, D.; Magil, S.
1996-08-01
The differential cross section dσ/dt for elastic ρ 0 photoproduction, γp→ρ 0 p(ρ 0 →π + π - ), has been measured in ep interactions at HERA. The squared four-momentum exchanged at the proton vertex, t, has been determined directly by measuring the momentum of the scattered proton using the ZEUS leading proton spectrometer (LPS), a large scale system of silicon micro-strip detectors operating close to the HERA proton beam. The LPS allows the measurement of the momentum of high energy protons scattered at small angles with accuracies of 0.4% for the longitudinal momentum and 5 MeV for the transverse momentum. Photoproduction of ρ 0 mesons has been investigated in the interval 0.073 2 , for photon virtualities q 2 2 and photon-proton centre-of-mass energies between 50 and 100 GeV. In the measured range, the t distribution exhibits an exponential shape with a slope parameter b=9.8±0.8(stat.)±1.1(syst.) GeV -2 . The use of the LPS eliminates the contamination from events with diffractive dissociation of the proton into low mass states. (orig.)
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
International Nuclear Information System (INIS)
Haji-Saeid, S.M.
1981-01-01
Large deuteron vector and tensor asymmetries were measured for the first time at intermediate energies. The polarized deuteron beam (with tensor and vector components of 0.75 and 0.25, respectively) was used at energies of 2.0, 1.6, and 1.2 GeV. The tensor and vector quantities P/sub yy/ and P/sub y/ were extracted from the data obtained within beam polarization normal to the scattering plane, and P/sub xx/ was obtained when the polarization was precessed into the scattering plane. Analysis of the data using multiple scattering theory demonstrates the importance of the noneikona correction to the Glauber Model and also the sensitivity of the data to double-spin flip components of the NN amplitudes. The differential cross section for the 12 C(p,p') 12 C* (15.11 MeV, 1 + , T=1) reaction was measured at 800 MeV; the range of the angular distribution corresponds to momentum transfers of 0.7 to 2.4 fm -1 (1 to 3.3 m/sub π/). The cross section decreases almost exponentially at large angles; no maximum is observed in the region where nuclear critical opalescence might be expected. Cross sections measured in parallel to the 15.11-MeV state were for the levels at 11.83 (2 - ), 12.71 (1 + ), 13.35 (2 - ), 16.1 (2 + ), and 16.58 (2 - ) MeV. 86 figures 18 tables
Elastic scattering and charge exchange reaction studies with {sup 6}He, {sup 10,11}Be
Energy Technology Data Exchange (ETDEWEB)
Roussel-Chomaz, P; Cortina-Gil, M D; Mittig, W; Casandjian, J M; Chartier, M [Grand Accelerateur National d` Ions Lourds (GANIL), 14 - Caen (France); Alamanos, N; Auger, F; Fekou-Youmbi, V [CEA Centre d` Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. d` Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l` Instrumentation Associee; Barrette, J [McGill Univ., Montreal, PQ (Canada); Blumenfeld, Y [Paris-11 Univ., 91 - Orsay (France). Inst. de Physique Nucleaire; and others
1996-12-31
The elastic scattering and charge exchange reaction of {sup 6}He, {sup 10,11}Be secondary beams on proton and {sup 12}C targets have been measured. The combined use of SISSI and SPEG allowed to obtain very good quality data in terms of energy and angular resolution. Preliminary analyses of the angular distributions using global parameter set for the optical model potentials, as well as more microscopic approaches are presented. (author). 14 refs.
rvec p + 13 rvec C elastic scattering at 500 MeV
International Nuclear Information System (INIS)
Tanaka, N.
1990-01-01
For the first time, an elastic scattering experiment was performed at LAMPF using polarized protons and a polarized target nucleus (rvec p + 13 rvec C). The analyzing powers [A ooon (Θ)] and [A oonn (Θ)] were measured using an incident beam energy of 500 MeV over the laboratory angular range of 10 degree--30 degree. Motivation for the experiment and some preliminary results and conclusions are presented. 12 refs., 7 figs
Measurement of proton inelastic scattering cross sections on fluorine
Energy Technology Data Exchange (ETDEWEB)
Chiari, M., E-mail: chiari@fi.infn.it [Department of Physics and Astronomy, University of Florence and INFN Florence, Sesto Fiorentino (Italy); Caciolli, A. [Department of Physics and Astronomy, University of Padua and INFN Padua, Padova (Italy); Calzolai, G. [Department of Physics and Astronomy, University of Florence and INFN Florence, Sesto Fiorentino (Italy); Climent-Font, A. [CMAM, Universidad Autonoma de Madrid, Madrid (Spain); Lucarelli, F.; Nava, S. [Department of Physics and Astronomy, University of Florence and INFN Florence, Sesto Fiorentino (Italy)
2016-10-01
Differential cross-sections for proton inelastic scattering on fluorine, {sup 19}F(p,p’){sup 19}F, from the first five excited levels of {sup 19}F at 110, 197, 1346, 1459 and 1554 keV were measured for beam energies from 3 to 7 MeV at a scattering angle of 150° using a LiF thin target (50 μg/cm{sup 2}) evaporated on a self-supporting C thin film (30 μg/cm{sup 2}). Absolute differential cross-sections were calculated with a method not dependent on the absolute values of collected beam charge and detector solid angle. The validity of the measured inelastic scattering cross sections was then tested by successfully reproducing EBS spectra collected from a thick Teflon (CF{sub 2}) target. As a practical application of these measured inelastic scattering cross sections in elastic backscattering spectroscopy (EBS), the feasibility of quantitative light element (C, N and O) analysis in aerosol particulate matter samples collected on Teflon by EBS measurements and spectra simulation is demonstrated.
International Nuclear Information System (INIS)
Guryn, W.
1998-02-01
The authors are describing an experiment to study proton-proton (pp) elastic scattering experiment at the Relativistic Heavy Ion Collider (RHIC). Using both polarized and unpolarized beams, the experiment will study pp elastic scattering from √s = 50 GeV to √s = 500 GeV in two kinematical regions. In the Coulomb Nuclear Interference (CNI) region, 0.0005 2 , they will measure and study the s dependence of the total and elastic cross sections, σ tot and σ el ; the ratio of the real to the imaginary part of the forward elastic scattering amplitude, ρ; and the nuclear slope parameter of the pp elastic scattering, b. In the medium |t|-region, |t| 2 , they plan to study the evolution of the dip structure with s, as observed at ISR in the differential elastic cross section, dσ el /dt, and the s and |t| dependence of b. With the polarized beams the following can be measured: the difference in the total cross sections as function of initial transverse spin states Δσ T , the analyzing power, A N , and the transverse spin correlation parameter A NN . The behavior of the analyzing power A N at RHIC energies in the dip region of dσ el /dt, where a pronounced structure was found at fixed-target experiments will be studied. The relation of pp elastic scattering to the beam polarization measurement at RHIC is also discussed
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 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.
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
Virtual Compton scattering off protons at moderately large momentum transfer
International Nuclear Information System (INIS)
Kroll, P.
1996-01-01
The amplitudes for virtual Compton scattering off protons are calculated within the framework of the diquark model in which protons are viewed as being built up by quarks and diquarks. The latter objects are treated as quasi-elementary constituents of the proton. Virtual Compton scattering, electroproduction off protons and the Bethe-Heitler contamination are photon discussed for various kinematical situations. We particularly emphasize the role of the electron asymmetry for measuring the relative phases between the virtual Compton and the Bethe-Heitler amplitudes. It is also shown that the model is able to describe very well the experimental data for real Compton scattering off protons. (orig.)
International Nuclear Information System (INIS)
Pitcher, E.J.; Ferguson, P.D.; Russell, G.J.; Prael, R.E.; Madland, D.G.; Court, J.D.; Daemen, L.L.; Wechsler, M.S.
1997-01-01
The latest release of the medium-energy Monte Carlo transport code LAHET includes a new nucleon-nucleus elastic scattering treatment based on a global medium-energy phenomenological optical-model potential. Implementation of this new model in LAHET allows nuclear elastic scattering for neutrons with energies greater than 15 MeV and for protons with energies greater than 50 MeV. Previous investigations on the impact of the new elastic scattering data revealed that the addition of the proton elastic scattering channel can lead to a significant increase in the calculated damage energy under certain conditions. The authors report here results on the impact of the new elastic scattering data on calculated displacement cross sections in various elements for neutrons with energies in the range 16 to 3,160 MeV. Calculated displacement cross sections at 20 MeV in low-mass materials are in better agreement with SPECTER-calculated cross sections
Measurement of the polarization correlation coefficient in elastic pp scattering at 610 MeV
International Nuclear Information System (INIS)
Borisov, N.S.; Glonti, L.N.; Kazarinov, M.Yu.
1977-01-01
The polarization correlation coefficient Csub(nn) for elastic pp scattering at 610+-10 MeV was measured for four scattering angles: 40, 67, 78 and 90 deg (c.m.s.). A polarized proton beam with a maximum polarization of 0.39+-0.02 and a polarized proton target of the frozen type were used. The maximum polarization of the target was 0.97+-0.04. The experimental procedure is described in detail. The Csub(nn) measured are compared with the results of a phase analysis and the findings at 575 MeV obtained elsewhere. The Csub(nn) coefficients are shown to be valuable to discriminate alternative solutions of the phase analysis. The polarized proton targets of the frozen type, no accounting the complexity of their design, are emphasized to be rather reliable and convenient devices for conducting experiments at accelerators
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.
Small-angle p-p elastic scattering at energies between 285 and 572 Me V
Aebischer, D; Greeniaus, L G; Hess, R; Junod, A; Lechanoine-Leluc, C; Nikles, J C; Rapin, D; Serre, Claude; Werren, D W
1976-01-01
Low energy proton-proton elastic scattering has been studied using an arrangement of multiwire proportional chambers at the CERN synchrocyclotron. Accurate measurements of the angular distribution for laboratory scattering angles in the range 1.5 to 10 degrees have been made at eight incident kinetic energies between 285 and 572 MeV. The interferences between the Coulomb and nuclear scattering amplitudes is used to determine the ratio alpha /sub p/=Re phi /sup N //sub +/(o)/Im phi /sup N//sub +/(o), where phi /sup N//sub +/(o) is the non-flip nuclear forward amplitude. alpha p is found to be positive and falling with energy, but is sensitive to the type of parameterization used. Reasonable consistency with dispersion relation calculations is obtained. (21 refs).
Inelastic scattering of polarized protons and nuclear deformation in 16O, 18O
International Nuclear Information System (INIS)
de Swiniarski, R.; Pham, D.L.
1984-01-01
Many data concerning inelastic scattering of polarized protons at intermediate energy are now available. We have analyzed some of these data coming from LAMPF at 800 MeV for 16 O (6) and 18 O (7) in order to further study nuclear deformations for these light nuclei. Analyzing powers (A(theta)) and cross-sections ((σ/theta)) for elastic and inelastic scattering of 800 MeV polarized protons from 16 O and 18 O have been analyzed in the coupled-channels (CC) collective model using the code ECIS from Raynal
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.
International Nuclear Information System (INIS)
Amado, R.D.; Sparrow, D.A.
1984-01-01
The importance of inelastic channels in proton-nucleus scattering grows with momentum transfer, q, so that for large q coupled channels are required. This happens when the elastic and inelastic cross sections become comparable. We incorporate these ideas in a simple analytic framework to explain the large angle p- 208 Pb elastic scattering data at 800 MeV for which standard optical model calculations have failed completely
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.)
Equipment and software for the experiment on polarized proton scattering on hydrogen and nuclei
International Nuclear Information System (INIS)
Buklej, A.E.; Govorun, N.N.; Zhurkin, V.V.
1980-01-01
Installation for the conduction of polarization measurements upon the beam of polarized protons with the 2.1 GeV/c momentum using ITEP synchrotron is described. The installation is designed for polarization measurement in elastic pp-scattering and asymmetry in summary (elastic and inelastic without meson production) scattering of polarized protons upon nuclei in the angle range up to 180 mrad, as well as polarization in elastic pn-scattering. The installation consists of 18 two-coordinate magnetostriction wire spark chambers (s.c.), emitting counters, the system of veto-counters surrounding the target, liquid hydrogen or (deuterium) target and magnet to conduct pulse analysis of scattered particles in the background measurements. Primary processing of the material is conducted on the basis of modernized programs using the M-220 and BESM-6 computers. With a help of the experimental installation described asymmetry measurement on hydrogen, Li, C, Al, Ca have been conducted. The prospect of use of the method described to separate elastic reactions in the range of very small momentum transmitted, where the background of inelastic interactions can be decreased to the negligibly low level, for precise measurement of elastic reactions cross sections and the study of polarization phenomena in the range of coulomb interference is underlined [ru
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
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)
Microscopic description of elastic and direct inelastic nucleon scattering off spherical nuclei
Energy Technology Data Exchange (ETDEWEB)
Dupuis, M. [CEA, DAM, DIF, Arpajon (France)
2017-05-15
The purpose of this study is to improve the modeling of nucleon direct inelastic scattering to the continuum using a microscopic and parameter-free approach. For the first time, direct elastic scattering, inelastic scattering to discrete excitations and to the continuum are described within a microscopic approach without adjustable parameters. Proton scattering off {sup 90}Zr and {sup 208}Pb are the reactions used as test case examples of the calculations. The model uses the Melbourne g-matrix and the Random Phase Approximation description of nuclear states, implemented with the Gogny D1S interaction. The relevant optical and transition potentials in a finite nucleus are calculated within a local density approximation. As we use the nuclear matter approach we limit our study to incident energies above 40 MeV. We first checked that this model provides an accurate account of measured cross sections for elastic scattering and inelastic scattering to discrete states. It is then applied to the direct inelastic scattering to the continuum considering all one-phonon excitations predicted within the RPA approach. This accounts for a part of the direct pre-equilibrium emission, often labeled as the one-step direct process in quantum-based approaches. Our approach provides a very accurate description of angular distributions where the one-step process dominates. The impact of collective excitations is shown to be non negligible for energy transfer to the target up to 20 MeV, decreasing as the incident energy increases. For incident energies above 80 MeV, our modeling provides a good account of direct proton emission for an energy transfer to the target up to 30 MeV. However, the proton emission we predict underestimates the measured cross sections for incident energies below 80 MeV. We compare our prediction to those of the phenomenological exciton model to help interpret this result. Directions that may improve our modeling are discussed. (orig.)
Microscopic description of elastic and direct inelastic nucleon scattering off spherical nuclei
Dupuis, M.
2017-05-01
The purpose of this study is to improve the modeling of nucleon direct inelastic scattering to the continuum using a microscopic and parameter-free approach. For the first time, direct elastic scattering, inelastic scattering to discrete excitations and to the continuum are described within a microscopic approach without adjustable parameters. Proton scattering off 90Zr and 208Pb are the reactions used as test case examples of the calculations. The model uses the Melbourne g-matrix and the Random Phase Approximation description of nuclear states, implemented with the Gogny D1S interaction. The relevant optical and transition potentials in a finite nucleus are calculated within a local density approximation. As we use the nuclear matter approach we limit our study to incident energies above 40 MeV. We first checked that this model provides an accurate account of measured cross sections for elastic scattering and inelastic scattering to discrete states. It is then applied to the direct inelastic scattering to the continuum considering all one-phonon excitations predicted within the RPA approach. This accounts for a part of the direct pre-equilibrium emission, often labeled as the one-step direct process in quantum-based approaches. Our approach provides a very accurate description of angular distributions where the one-step process dominates. The impact of collective excitations is shown to be non negligible for energy transfer to the target up to 20 MeV, decreasing as the incident energy increases. For incident energies above 80 MeV, our modeling provides a good account of direct proton emission for an energy transfer to the target up to 30 MeV. However, the proton emission we predict underestimates the measured cross sections for incident energies below 80 MeV. We compare our prediction to those of the phenomenological exciton model to help interpret this result. Directions that may improve our modeling are discussed.
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.)
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.
Islam, M M
2013-01-01
We study high energy $\\small{\\rm{pp}}$ and $\\small{\\rm{\\bar {p}p}}$ elastic scattering in the TeV region based on an effective field theory model of the proton. We phenomenologically investigate the main processes underlying elastic scattering and quantitatively describe the measured elastic d$\\small{\\sigma}$/dt at energies 7.0 TeV (LHC $\\small{\\rm{pp}}$), 1.96 TeV (Tevatron $\\small{\\rm{\\bar {p}p}}$), and 0.630 TeV (SPS $\\small{\\rm{\\bar {p}p}}$). Finally, we give our prediction for $\\small{\\rm{pp}}$ elastic d$\\small{\\sigma}$/dt at 14 TeV that will be measured by the TOTEM Collaboration.
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
Parity violation in proton-proton scattering at 221 MeV
International Nuclear Information System (INIS)
Berdoz, A.R.; Birchall, J.; Bland, J.B.; Campbell, J.R.; Green, A.A.; Hamian, A.A.; Lee, L.; Page, S.A.; Ramsay, W.D.; Reitzner, S.D.; Sekulovich, A.M.; Sum, V.; Oers, W.T.H. van; Woo, R.J.; Bowman, J.D.; Mischke, R.E.; Coombes, G.H.; Helmer, R.; Kadantsev, S.; Levy, C.D.P.
2003-01-01
TRIUMF experiment 497 has measured the parity-violating longitudinal analyzing power A z in p(vector sign)p elastic scattering at 221.3 MeV incident proton energy. This comprehensive paper includes details of the corrections, some of magnitude comparable to A z itself, required to arrive at the final result. The largest correction was for the effects of first moments of transverse polarization. The addition of the result, A z =[0.84±0.29 (stat.)±0.17 (syst.)]x10 -7 , to the p(vector sign)p parity-violation experimental data base greatly improves the experimental constraints on the weak meson-nucleon coupling constants h ρ pp and h ω pp , and also has implications for the interpretation of electron parity-violation experiments
International Nuclear Information System (INIS)
Guryn, W.
1995-01-01
The author is describing an experiment to study proton-proton (pp) elastic scattering experiment at the Relativistic Heavy Ion Collider (RHIC). Using both polarized and unpolarized beams, the experiment will study pp elastic scattering from √s = 60 GeV to √s = 500 GeV in two kinematical regions .In the Coulomb Nuclear Interference (CNI) region, 0.0005 2 , we will measure and study the s dependence of the total and elastic cross sections, σ tot and σ el ; the ratio of the real to the imaginary part of the forward elastic scattering amplitude, ρ; and the nuclear slope parameter of the pp elastic scattering, b. In the medium |t|, |t| ≤ 1.5 (GeV/c) 2 , we plan to study the evolution of the dip structure with s, as observed at ISR in the differential elastic cross section, dσ el /dt, and the s and |t| dependence of b. With the polarized beams the following can be measured: the difference in the total cross sections as function of initial transverse spin stated Δσ T , the analyzing power, A N , and the transverse spin correlation parameter A NN . The behavior of the analyzing power A N at RHIC energies in the dip region of dσ el /dt, where a pronounced structure was found at fixed-target experiments will be studied
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
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 ...
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
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
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
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
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.
Gluon bremsstrahlung and elastic scattering of hadrons
International Nuclear Information System (INIS)
Povh, B.
2001-01-01
The differential and the total cross sections in high energy hadron-proton interactions give a beautiful insight in the low Q 2 structure of the nucleon. The cross section is composed of two parts: a large energy independent part corresponding to the interaction of the valence quark with the target without gluon radiation and an energy dependent part caused by gluon bremsstrahlung. The gluons are located at small transverse distances of about 0.3 fm from the valence quarks. The model with two scales, the size of the hadron (R 2 ∼ 1 fm 2 ) and the size of the gluonic cloud (r 0 2 ∼ 0.1 fm 2 ), correctly predicts the total and the differential cross sections and the behaviour of diffractive dissociation in hadronic and deep inelastic events. (orig.)
An experimental test of charge symmetry in n-p elastic scattering
International Nuclear Information System (INIS)
Birchall, J.; Davison, N.E.; Gubler, H.P.
1982-06-01
An experiment is described to investigate the isospin-mixing, charge-symmetry breaking component in the n-p interaction. The experiment measures the difference ΔA between the neutron and proton analyzing power Asub(n) and Asub(p) in n-p elastic scattering at 500 MeV. The experiment consists of two interleaved phases in which polarised neutrons, respectively unpolarised neutrons are scattered from an unpolarised, respectively polarised proton target of the frozen spin type. Designed as a null-measurement requiring no accurately known polarisation standards, the experiment determines the difference in angle at which Asub(n) and Asub(p) cross through zero. It is intended to provide an unambiguous test of a class IV charge-symmetry breaking effect to the level of ΔA approximately equal to 0.001, corresponding to a laboratory angle difference at zero crossing of approximately 0.05 0
International Nuclear Information System (INIS)
Ibrayeva, E.T.; Prmantayeva, B. A.; Kuterbekov, K. A.; Temerbayev, A. A.; Tleulessova, I. K.; Zhigalova, A.
2012-01-01
The purpose of the present work is studying the structure of various isotopes of lithium 6 , 7 , 8 , 9 Li and the mechanism of their interaction with protons in the processes of elastic scattering. Differential cross sections and analyzing powers for elastic proton scattering from nuclei of Li are calculated in the context of the Glauber diffraction theory. Comparison of the result of calculations with the experimental data has allowed to draw conclusions on the structure of the given nuclei and their interaction mechanisms. (Authors)
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
Nuclear structure of 41Ca from inelastic proton scattering
International Nuclear Information System (INIS)
Vold, P.B.; Cline, D.; Voigt, M.J.A. de
1977-01-01
Angular distributions have been measured for inelastic and elastic scattering of 19 MeV protons on 40 41 Ca. A total of 89 levels were identified below 6.4 MeV in 41 Ca with an energy resolution of 12 keV. Inelastic transition strengths have been extracted using DWBA theory with a vibrational model form factor. These transition strengths correlate well with inelastic α-scattering and electromagnetic values. The quadrupole strengths are interpreted in terms of the coexistence model and imply that the excited-core admixture in the ground states of both 40 Ca and 41 Ca are approximately 5%. The octupole strengths in 41 Ca exhibits features characteristic of the weak coupling of an fsub(7/2) neutron to the lowest 3 - state in 40 Ca. The l = 5 strength exhibits a similar weak-coupling behavior. In both cases the microscopic structure appreciably reduces the transition strength for the highest spin member of the weak-coupling multiplets. (Auth.)
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.
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
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
Detection method of elastic scattering in the Coulomb interference region: scintillation target
International Nuclear Information System (INIS)
Azaiez, Hamza.
1981-01-01
Measurement of polarization in (p-p) elastic scattering in the Coulomb interference region is considered as a valid method for calibrating high energy polarized proton beams. Possibility of using a scintillation target to detect low energy recoil protons in this /t/ region has been studied by using a 4 GeV/c π - beam from CERN PS. The results obtained with a steack of thin plastic scintillators, each 1 mm thick, showed the feasibility of detecting recoil protons in a /t/ range as low a 5.10 -3 (GeV/c) 2 . This method thus confirmed experimentally can be used also to measure, using a polarized beam, polarization in Coulomb interference region [fr
Unified semimicroscopic approach scattering of low energy protons and alpha-particles by nuclei
International Nuclear Information System (INIS)
Dao Tien Khoa; Kukhtina, I.N.; Knyaz'kov, O.M.; Feofilov, G.A.
1988-01-01
The unified approach has been developed to the description of the interaction of low energy nucleons and α-particles with nuclei. The analysis of elastic and inelastic scattering of 25.05 MeV protons and 104 MeV α-particles from 90 Zr is made. The differences in deformations of neutron and proton density distributions for 90 Zr nucleus are extracted. The energy dependence of the obtained α-particle - nucleus semimicroscopic potential is investigated, including the energy dependence for the geometry of the potential. The feaures of angular distributions of elastic α-particle scattering and the role of nucleon-nucleon correlations are analysed as a function of α-particle energy
Energy Technology Data Exchange (ETDEWEB)
Aksouh, F
2002-12-01
The elastic proton scattering from the halo nuclei {sup 6}He and {sup 8}He was investigated in inverse kinematics at energies around 700 MeV/u with the aim to deduce the differential cross sections for the region of high momentum transfer, covering the first diffraction minimum. For this purpose, a liquid-hydrogen target was specially developed and used for the first time allowing to obtain low-background data as compared to commonly used targets made from C-H compounds. Previous data taken in the region of small momentum transfer were sensitive to the size and the peripheral shape of the total nuclear matter density distribution but not to the inner part. The present data allow for a more detailed insight in the structure of the alike core in {sup 6,8}He through a better determination of the matter density distributions. Several density distributions calculated from different microscopic models were used to derive elastic scattering cross sections which are compared with the obtained data. (author)
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
International Nuclear Information System (INIS)
Ismail, Atef; Lee, Yen Cheong; Tammam, M.
2015-01-01
Proton elastic scattering at various incident energies is one method to study nuclear density distributions and nuclear radii. Single folding potential describing the p-scattering on 40 Ca over a broad energy range 9–48.4 MeV is constructed. The resulting potential does not need any renormalization to fit the measured elastic scattering angular distributions and total reaction cross-sections. Furthermore, correlation between volume integral and proton incident energy is discussed. Theoretical calculations are in a good agreement with existing experimental data. (author)
Test of time reversal invariance in p-p elastic scattering at 198.5 MeV
International Nuclear Information System (INIS)
Davis, C.A.; Greeniaus, L.G.; Moss, G.A.
1986-01-01
A precise measurement of the polarization-analyzing power difference in p-p elastic scattering has been made at 198.5 MeV to improve the experimental limits on time reversal violation in proton-proton scattering in this energy region. The experiment was performed in a kinematic regime where sensitivities to time reversal violating amplitudes should be high. Experimental methods which eliminated the need to refer to absolute values of the beam polarization or to the analyzing power of a polarimeter were used. The result is (P-A) = 0.0047 with a statistical uncertainty of +- 0.0025 and a systematic uncertainty of +- 0.0015
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.
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
Simulation of effects of incident beam condition in p-p elastic scattering
International Nuclear Information System (INIS)
Yu Lei; Zhang Gaolong; Le Xiaoyun; Tanihata, I.
2014-01-01
The simulation is performed for the monitors of beam direction and beam position for p-p elastic scattering. We set several variables to simulate the monitors of incident beam condition changes: beam positions at the quadrupole magnet and target in beam line polarimeter (BLP2), distance between quadrupole magnet and target, size of plastic scintillators, distance between the target in BLP2 and the centers of plastic scintillators, and beam polarization. Through the rotation of the coordinate system, the distributions of scattered and recoiled protons in the laboratory system were obtained. By analyzing the count yields in plastic scintillators at different beam positions, we found that the beam incident angular change (0.35°) could be detected when the asymmetry of geometries of left and right scintillators in BLP2 was changed by 6%. Therefore, the scattering angle measured in the experiment can be tracked by these monitors. (authors)
Study on proton spin flip in scattering by Ti and Fe nuclei
International Nuclear Information System (INIS)
Korbetskij, E.V.; Prokopenko, V.S.; Sklyarenko, V.D.; Chernievskij, V.K.; Shustov, A.V.
1981-01-01
Spin-orbital effects and mechanisms of inelastic scattering of protons with energy of 6.9 MeV by sup(14, 48)Ti and sup(54, 56, 58)Fe are studied by the analysis of experimental results within the framework of the method of coupled channels. Simultaneously angular dependences of cross sections of elastic and inelastic (two first 2 + levels) scatterings and a probability of spin flip of proton at inelastic scattering are analysed. Experimental data were used for analysis, obtained in the given work, as well as the data published earlier. Targets are used in experiment which are in the form of self-sustaining fine (1-2 mg cm -2 ) films, enriched with corresponding isotope. Cross section determination error is 8% in the average. Obtained angular dependences of spin flip probability for sup(54, 56)Fe at Esub(p)=6.9 MeV are very similar in form and close in value to analogous at Esub(p)= 6 MeV, and differ greatly for 56 Fe at Esub(p)=5.88 MeV. Angular distributions of spin flip probabilities of protons from sup(54, 56)Fe (ppsub(1)) reaction at energies of 10, 11 and 12 MeV show the sufficient energy dependence of their shape and value. Experimental data are described satisfactorily witohin the framework of the cupled channel method namely - differential cross sections of elastic and inelastic scattering and angular dependences of the probability of spin flip at the interaction of protons with 6.9 MeV energy with sup(46, 48)Ti and sup(54, 56, 58)Fe nuclei. Difficulties, appearing in the description of cross sections of elastic scattering in case of sup(46, 48)Ti and of inelastic one for 56 Fe show that indirect processes are of importance in the present energy range and they should be taken into consideration [ru
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.
Measurements of Electron Proton Elastic Cross Sections for 0.4
International Nuclear Information System (INIS)
Christy, M.E.; Abdellah Ahmidouch; Christopher Armstrong; John Arrington; Arshak Asaturyan; Steven Avery; Baker, O.; Douglas Beck; Henk Blok; Bochna, C.W.; Werner Boeglin; Peter Bosted; Maurice Bouwhuis; Herbert Breuer; Brown, D.S.; Antje Bruell; Roger Carlini; Nicholas Chant; Anthony Cochran; Leon Cole; Samuel Danagoulian; Donal Day; James Dunne; Dipangkar Dutta; Rolf Ent; Howard Fenker; Fox, B.; Liping Gan; Haiyan Gao; Kenneth Garrow; David Gaskell; Ashot Gasparian; Don Geesaman; Paul Gueye; Mark Harvey; Roy Holt; Xiaodong Jiang; Cynthia Keppel; Edward Kinney; Yongguang Liang; Wolfgang Lorenzon; Allison Lung; Pete Markowitz; Martin, J.W.; Kevin Mcilhany; David Mckee; David Meekins; Miller, M.A.; Richard Milner; Joseph Mitchell; Hamlet Mkrtchyan; Robert Mueller; Alan Nathan; Gabriel Niculescu; Maria-ioana Niculescu; Thomas O'neill; Vassilios Papavassiliou; Stephen Pate; Rodney Piercey; David Potterveld; Ronald Ransome; Joerg Reinhold; Rollinde, E.; Philip Roos; Adam Sarty; Reyad Sawafta; Elaine Schulte; Edwin Segbefia; Smith, C.; Samuel Stepanyan; Steffen Strauch; Vardan Tadevosyan; Liguang Tang; Raphael Tieulent; Alicia Uzzle; William Vulcan; Stephen Wood; Feng Xiong; Lulin Yuan; Markus Zeier; Benedikt Zihlmann; Vitaliy Ziskin
2004-01-01
We report on precision measurements of the elastic cross section for electron-proton scattering performed in Hall C at Jefferson Lab. The measurements were made at 28 distinct kinematic settings covering a range in momentum transfer of 0.4 < Q2 < 5.5 (GeV/c)2. These measurements represent a significant contribution to the world's cross section data set in the Q2 range, where a large discrepancy currently exists between the ratio of electric to magnetic proton form factors extracted from previous cross section measurements and that recently measured via polarization transfer in Hall A at Jefferson Lab. This data set shows good agreement with previous cross section measurements, indicating that if a heretofore unknown systematic error does exist in the cross section measurements, then it is intrinsic to all such measurements
Intermediate energy proton and light-ion scattering
International Nuclear Information System (INIS)
Moss, J.M.
1981-01-01
A review is presented of recent (1979-81) developments in the field of intermediate-energy proton and light-ion scattering from nuclei. New theoretical and calculational techniques of particular interest to experimentalists are discussed. Emphasis is placed on topics in nuclear structure physics - giant resonances, pion-condensation precursor phenomena, and polarization transfer (spin-flip) experiments - where intermediate energy proton and light-ion scattering has made new and unique contributions
Backward elastic p3He-scattering and high momentum components of 3He wave function
International Nuclear Information System (INIS)
Uzikov, Yu.N.
1998-01-01
It is shown that owing to a dominance of np-pair transfer mechanism of backward elastic p 3 He-scattering for incident proton kinetic energies T p > 1 GeV the cross section of this process is defined mainly by the values of the Faddeev component of the wave function of 3 He nucleus, φ 23 (q 23 , p 1 ), at high relative momenta q 23 > 0.6 GeV/c of the NN-pair in the 1 S 0 -state and at low spectator momenta p 1 ∼ 0 - 0.2 GeV/c
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
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
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.)
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)
Collimator scatter and 2D dosimetry in small proton beams
van Luijk, P.; van 't Veld, A.A.; Zelle, H.D.; Schippers, J.M.
Monte Carlo simulations have been performed to determine the influence of collimator-scattered protons from a 150 MeV proton beam on the dose distribution behind a collimator. Slit-shaped collimators with apertures between 2 and 20 mm have been simulated. The Monte Carlo code GEANT 3.21 has been
Study of the diffusion movements of water by quasi-elastic scattering of slow neutrons
International Nuclear Information System (INIS)
Yamazaki, Ione Makiko
1980-01-01
The diffusion movements of water at three different temperatures in the liquid state have been studied by slow neutron quasi-elastic scattering. The measurements have been performed using the IPEN Triple Axis Spectrometer. Broadening and integrated intensity of the quasi-elastic line have been determined for several momentum transfer (K) in the range 0,7627 ≤ K ≤ 2,993 A -1 . The broadening of the quasi-elastic peaks as function of momentum transfer (K) observed at various temperatures has been interpreted in terms of globular diffusion models. The results obtained at 30 deg C have been explained in a consistent way considering the translational and rotational globular diffusion movements. To describe the results obtained at 55 deg and 70 deg C only the translational globular diffusion model was sufficient. This analysis indicates the existence in water of globules with distance of the farest proton position to the center of gravity of the globule 4,5 A, corroborating the idea of quasi-crystalline structure for water. The Debye-Waller factor has been obtained through the analysis of the integrated intensity of quasi-elastic scattering peaks over the K 2 measured range. From this analysis an estimative of the mean square displacement was obtained. (author)
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.
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
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
The Proton Coulomb Form Factor from Polarized Inclusive e-p Scattering
Energy Technology Data Exchange (ETDEWEB)
Harris, Christopher Matthew [Univ. of Virginia, Charlottesville, VA (United States)
2001-05-01
The proton form factors provide information on the fundamental properties of the proton and provide a test for models based on QCD. In 1998 at Jefferson Lab (JLAB) in Newport News, VA, experiment E93026 measured the inclusive e-p scattering cross section from a polarized ammonia (^{15}NH_{3}) target at a four momentum transfer squared of Q^{2} = 0.5 (GeV/c)^{2}. Longitudinally polarized electrons were scattered from the polarized target and the scattered electron was detected. Data has been analyzed to obtain the asymmetry from elastically scattered electrons from hydrogen in ^{15}NH_{3}. The asymmetry, A_{p}, has been used to determine the proton elastic form factor G_{Ep}. The result is consistent with the dipole model and data from previous experiments. However, due to the choice of kinematics, the uncertainty in the measurement is large.
Investigation of {sup 17}F+p elastic scattering at near-barrier energies
Energy Technology Data Exchange (ETDEWEB)
El-Azab Farid, M. [Assiut University, Physics Department, Assiut (Egypt); Ibraheem, Awad A. [Al-Azhar University, Physics Department, Assiut (Egypt); King Khalid University, Physics Department, Abha (Saudi Arabia); Al-Hajjaji, Arwa S. [Taiz University, Physics Department, Taiz (Yemen)
2015-10-15
The {sup 17}F +p elastic scattering at two near-barrier energies of 3.5 and 4.3 MeV/nucleon, have been analyzed in the framework of the single folding approach. The folded potentials are constructed by folding the density-dependent (DDM3Y) effective nucleon-nucleon interaction over the nuclear density of the one-proton halo nucleus {sup 17}F. Two versions of the density are considered. In addition, two versions of the one-nucleon knock-on exchange potentials are introduced to construct the real microscopic potentials. The derived potentials supplemented by phenomenological Woods-Saxon imaginary and spin-orbit potentials produced excellent description of the differential elastic scattering cross sections at the higher energy without need to introduce any renormalization. At the lower energy, however, in order to successfully reproduce the data, it is necessary to reduce the strength of the constructed real DDM3Y potential by about 25% of its original value. Furthermore, good agreement with data is obtained using the extracted microscopic DDM3Y potentials for both real and imaginary parts. Moreover, the interesting notch test is applied to investigate the sensitivity of the elastic scattering cross section to the radial distribution of the constructed microscopic potentials. The extracted reaction (absorption) cross sections are, also, investigated. (orig.)
Investigation of 17F+p elastic scattering at near-barrier energies
International Nuclear Information System (INIS)
El-Azab Farid, M.; Ibraheem, Awad A.; Al-Hajjaji, Arwa S.
2015-01-01
The 17 F +p elastic scattering at two near-barrier energies of 3.5 and 4.3 MeV/nucleon, have been analyzed in the framework of the single folding approach. The folded potentials are constructed by folding the density-dependent (DDM3Y) effective nucleon-nucleon interaction over the nuclear density of the one-proton halo nucleus 17 F. Two versions of the density are considered. In addition, two versions of the one-nucleon knock-on exchange potentials are introduced to construct the real microscopic potentials. The derived potentials supplemented by phenomenological Woods-Saxon imaginary and spin-orbit potentials produced excellent description of the differential elastic scattering cross sections at the higher energy without need to introduce any renormalization. At the lower energy, however, in order to successfully reproduce the data, it is necessary to reduce the strength of the constructed real DDM3Y potential by about 25% of its original value. Furthermore, good agreement with data is obtained using the extracted microscopic DDM3Y potentials for both real and imaginary parts. Moreover, the interesting notch test is applied to investigate the sensitivity of the elastic scattering cross section to the radial distribution of the constructed microscopic potentials. The extracted reaction (absorption) cross sections are, also, investigated. (orig.)
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
Virtual compton scattering off protons at moderately large momentum transfer
Energy Technology Data Exchange (ETDEWEB)
Kroll, P; Schuermann, M [Wuppertal Univ. (Gesamthochschule) (Germany); Guichon, P A.M. [CEA Centre d` Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. d` Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l` Instrumentation Associee
1995-06-28
The amplitudes for virtual Compton scattering off protons are calculated within the framework of the diquark model in which protons are viewed as being built up by quarks and diquarks. The latter objects are treated as quasi-elementary constituents of the proton. Virtual Compton scattering, electroproduction of photons and the Bethe-Heitler contamination are discussed for various kinematical situations. We particularly emphasize the role of the electron asymmetry for measuring the relative phases between the virtual Compton and the Bethe-Heitler amplitudes. It is also shown that the model is able to describe very well the experimental data for real Compton scattering off protons. (authors). 35 refs., 8 figs., 1 tab.
Virtual compton scattering off protons at moderately large momentum transfer
International Nuclear Information System (INIS)
Kroll, P.; Schuermann, M.; Guichon, P.A.M.
1995-01-01
The amplitudes for virtual Compton scattering off protons are calculated within the framework of the diquark model in which protons are viewed as being built up by quarks and diquarks. The latter objects are treated as quasi-elementary constituents of the proton. Virtual Compton scattering, electroproduction of photons and the Bethe-Heitler contamination are discussed for various kinematical situations. We particularly emphasize the role of the electron asymmetry for measuring the relative phases between the virtual Compton and the Bethe-Heitler amplitudes. It is also shown that the model is able to describe very well the experimental data for real Compton scattering off protons. (authors). 35 refs., 8 figs., 1 tab
Forward elastic scattering and total cross-section at very high energies
International Nuclear Information System (INIS)
Castaldi, R.
1985-01-01
The successful cooling technique of antiproton beams at CERN has recently allowed the acceleration of proton and antiproton bunches simultaneously circulating in opposite directions in the SPS. Hadron-hadron collisions could so be produced at a centre-of-mass energy one order of magnitude higher than previously available, thus opening a new wide range of energies to experimentation. This technique also made it possible to replace one of the two proton beams in the ISR by a beam of antiprotons, allowing a direct precise comparison, by the same detectors, of pp and anti pp processes at the same energies. The recent results are summarized of the forward elastic scattering and total cross-section in this new energy domain. (Mori, K.)
Why the real part of the proton-proton forward scattering amplitude should be measured at the LHC
Energy Technology Data Exchange (ETDEWEB)
Bourrely, C.; Soffer, J. [Centre de Physique Theorique, UMR 6207 b, CNRS-Luminy, 13 - Marseille (France); Khuri, N.N. [Rockfeller Univ., (2) Physics Dept., New York, N.Y. (United States); Martin, A.; Tai Tsun Wu, J. [Conseil Europeen pour la recherche nucleaire, Theory Div., Geneve (Switzerland); Tai Tsun Wu, J. [Harvard Univ., Gordon Mc Kay Lab., Cambridge, MA (United States)
2005-07-01
For the energy of 14 TeV, to be reached at the Large Hadron Collider (LHC), we have had for some time accurate predictions for both the real and imaginary parts of the forward proton-proton elastic scattering amplitude. LHC is now scheduled to start operating in 2 years, and it is timely to discuss some of the important consequences of the measurements of both the total cross-section and the ratio of the real to the imaginary part ({rho}). An accurate prediction is given by the BSW model: {rho} = 0.122 with {sigma}(total) = 103.6 mb (at the LHC energy {radical}(s) = 14 TeV. If the experiment gives numbers compatible with those above, it will mean that the scale of violation is very much above the LHC energy or that the corresponding minimal size is much smaller. On the contrary a disagreement would give indication for new physics and we stress the importance of measuring the real part of the proton-proton forward scattering amplitude at LHC, because a deviation from existing theoretical predictions could be a strong sign for new physics.
Proton-proton Scattering Above 3 GeV/c
Energy Technology Data Exchange (ETDEWEB)
A. Sibirtsev, J. Haidenbauer, H.-W. Hammer S. Krewald ,Ulf-G. Meissner
2010-01-01
A large set of data on proton-proton differential cross sections, analyzing powers and the double-polarization parameter A{sub NN} is analyzed employing the Regge formalism. We find that the data available at proton beam momenta from 3 GeV/c to 50 GeV/c exhibit features that are very well in line with the general characteristics of Regge phenomenology and can be described with a model that includes the {rho}, {omega}, f{sub 2}, and a{sub 2} trajectories and single-Pomeron exchange. Additional data, specifically for spin-dependent observables at forward angles, would be very helpful for testing and refining our Regge model.
Universal fit to p-p elastic diffraction scattering from the Lorentz contracted geometrical model
International Nuclear Information System (INIS)
Hansen, P.H.; Krisch, A.D.
1976-01-01
The prediction of the Lorentz contracted geometical model for proton-proton elastic scattering at small angles is examined. The model assumes that when two high energy particles collide, each behaves as a geometrical object which has a Gaussian density and is spherically symmetric except for the Lorentz contraction in the incident direction. It is predicted that dsigma/dt should be independent of energy when plotted against the variable β 2 P 2 sub(perpendicular) sigmasub(TOT)(s)/38.3. Thus the energy dependence of the diffraction peak slope (b in an esup(-b mod(t))plot) is given by b(s)=A 2 β 2 sigmasub(TOT)(s)/38.3 where β is the proton's c.m. velocity and A is its radius. Recently measured values of sigmasub(TOT)(s) were used and an excellent fit obtained to the elastic slope in both t regions [-t 2 and 0.1 2 ] at all energies from s=6 to 4000(GeV/c) 2 . (Auth.)
Analysis of Quasi-Elastic e-n and e-p Scattering from Deuterium
Balsamo, Alexander; Gilfoyle, Gerard; CLAS12 Collaboration
2017-09-01
One of Jefferson Lab's goals is to unravel the quark-gluon structure of nuclei. We will use the ratio, R, of electron-neutron to electron-proton scattering on deuterium to probe the magnetic form factor of the neutron. We have developed an end-to-end analysis from simulation to extraction of R in quasi-elastic kinematics for an approved experiment with the CLAS12 detector. We focus on neutrons detected in the CLAS12 calorimeters and protons measured with the CLAS12 forward detector. Events were generated with the Quasi-Elastic Event Generator (QUEEG) and passed through the Monte Carlo code gemc to simulate the CLAS12 response. These simulated events were reconstructed using the latest CLAS12 Common Tools. We first match the solid angle for e-n and e-p events. The electron information is used to predict the path of both a neutron and proton through CLAS12. If both particles interact in CLAS12 the e-n and e-p events have the same solid angle. We select QE events by searching for nuclei near the predicted position. An angular cut between the predicted 3-momentum of the nucleon and the measured value, θpq, separates QE and inelastic events. We will show the simulated R as a function of the four-momentum transfer Q2. Work supported by the University of Richmond and the US Department of Energy.
Theoretical study of parity violating asymmetry in proton-proton (pp) scattering
International Nuclear Information System (INIS)
Singh, S.K.; Sajjad Athar, M.; Waris, Atiya
2000-01-01
Measurements of parity violating asymmetries in the pp scattering and proton-nucleus scattering with polarised protons provide a very useful tool to study the interplay of weak and strong interactions between the nucleons and within the nucleus. In order to understand these processes in terms of the conventional nucleon-nucleon interaction models, new experiments at the intermediate energies of 221 and 450 MeV and in the higher energy of multi GeV range are to be carried out
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...
Polarization measurements for P-12C elastic scattering between 40-75 MeV
International Nuclear Information System (INIS)
Kato, S.; Okada, K.; Kondo, M.; Shimizu, A.; Hosono, K.; Saito, T.; Matsuoka, N.; Nagamachi, S.; Nisimura, K.; Tamura, N.
1980-01-01
Absolute values of the polarization in p- 12 C elastic scattering have been measured at 60.0 and 64.5 MeV at 47.5 0 in the laboratory system using a double scattering method and a method to measure an asymmetry with a polarized beam. The results are P(60.0 MeV, 47.5 0 ) = 0.965 +- 0.011 and P(64.5 MeV, 47.5 0 ) = 0.975 +- 0.011. Based on these values, the polarization measurements have been extended to the energy range from 40-75 MeV at several angles around 47.5 0 using the polarized proton beam and the energy degrader. Differential cross sections and polarizations from 15-115 0 are also presented at 65 MeV. These data will be valuable for the monitoring of beam polarization in this energy region. (orig.)
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.
A model of quasi-free scattering with polarized protons
International Nuclear Information System (INIS)
Teodoro, M.R.
1976-01-01
A quantitative evaluation, based on a simple model for spin-free coplanar and asymmetric reaction in 16 O, for 215 MeV incoming polarized protons confirms the use of the strong effective polarization of the knocked-out proton by the spin-orbit coupling and of the strong dependence of free, medium energy, proton-proton cross section on the relative orientation of the proton spins. Effective polarizations, momentum distributions and correlation cross sections have been calculated for the 1p sub(1/2), 1 p sub(3/2) and 1s sub(1/2) states in 16 O, using protons totally polarized orthogonal to the scattering plane. Harmonic oscillator and square wells have been used to generate the bound state wave functions, whereas the optical potentials have been taken spin-independent and purely imaginary [pt
Directory of Open Access Journals (Sweden)
Shimizu Y.
2010-04-01
Full Text Available Measurements of a complete set of deuteron analyzing powers (iT11, T20, T21, T22 for elastic deuteron–proton scattering at 250 MeV/nucleon have been performed with polarized deuteron beams at RIKEN RI Beam Factory. The obtained data are compared with the Faddeev calculations based on the modern nucleon–nucleon forces together with the Tucson-Melbourne’99, and UrbanaIX three nucleon forces.
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
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
Inclusive proton spectra and total reaction cross sections for proton-nucleus scattering at 800 MeV
International Nuclear Information System (INIS)
McGill, J.A.
1981-08-01
Current applications of multiple scattering theory to describe the elastic scattering of medium energy protons from nuclei have been shown to be quite successful in reproducing the experimental cross sections. These calculations use the impulse approximation, wherein the scattering from individual nucleons in the nucleus is described by the scattering amplitude for a free nucleon. Such an approximation restricts the inelastic channels to those initiated by nucleon-nucleon scattering. As a first step in determining the nature of p + nucleus scattering at 800 MeV, both total reaction cross sections and (p,p') inclusive cross sections were measured and compared to the free p + p cross sections for hydrogen, deuterium, calcium 40, carbon 12, and lead 208. It is concluded that as much as 85% of all reactions in a nucleus proceed from interactions with a single nucleon in the nucleus, and that the impulse approximation is a good starting point for a microscopic description of p + nucleus interactions at 800 MeV
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
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
Spin dependence in high $p^{2}_{T}$ elastic pp and np scattering
Crabb, D G; Hansen, P.H.; Hauser, J.; Krisch, A.D.; Sandler, B.; Shima, T.; Terwilliger, K.M.; Crosbie, E.A.; Ratner, L.G.; Schultz, P.F.; Thomas, G.H.; O'Fallon, J.R.; Lin, A.D.; Salthouse, A.J.; Linn, S.L.; Perlmutter, A.; Karmakar, N.L.; Kyberd, P.
1979-01-01
Using the polarized proton capability of the Argonne ZGS the authors recently made 90 degrees /sub cm/ measurements of elastic pp scattering from 6 to 11.75 GeV/c, determining the parallel and anti- parallel pure initial spin state cross sections and the associated spin-spin parameter A/sub nn/ with the spins normal to the scattering plane. They find that the parallel to anti-parallel cross section ratio rises dramatically from 1.2+or-.06 at p/sub t//sup 2/=3.3 (GeV /c)/sup 2/ to 3.2+or-.4 at 4.8 (GeV/c)/sup 2/, similar to the p/sub T //sup 2/ dependence previously observed at the fixed laboratory momentum of 11.75 GeV/c. They have also extended the measurements at 6 GeV/c and find that A/sub nn/ has a small but sharp rise at 90 degrees /sub cm/. In addition a month of 12 GeV/c polarized deuteron acceleration in the ZGS enabled them to measure two A/sub nn/ at two points at 6 GeV/c for np elastic scattering: A/sub nn/=-.17+or-.04 at p/sub T//sup 2/=.8, A/sub nn/=-.19+or-.05 at P/sub T//sup 2/=1.0. These value...
Ambiguities of the phase analysis of the proton-proton scattering amplitude
International Nuclear Information System (INIS)
Grebenyuk, O.G.; Shklyarevskij, G.M.
1980-01-01
Ambiguities of the phase analysis of the proton-proton scattering amplitude are analysed. It is shown that for five measurements of polarization parameters sets there are ambiguities similar to the Gersten ambiguities in the phase analysis of πN scattering. A problem on additional experiments needed to eliminate these ambiguities is investigated. It is shown that for this purpose it suffices to measure three total cross sections with polarized and nonpolarized protons, thus determining the imaginary parts of amplitudes at THETA=0 and polarization parameters
Highlights of electron-proton deep inelastic scattering at HERA
International Nuclear Information System (INIS)
Feltesse, J.
1996-02-01
Salient results on deep inelastic scattering from the H1 and ZEUS collaborations are reviewed. These include preliminary measurements of the proton structure function F 2 extending to new regimes at both high Q 2 and low Q 2 and x, studies of the hadronic final states and discussion on QCD interpretations of low x data. New determination of α s from jet rates in deep inelastic scattering based on 1994 data are presented. A consistent picture of the gluon density in the proton at low x from a variety of processes is obtained. (author)
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.
Karlsson, Maths
2015-01-07
This article is concerned with the use of quasielastic neutron scattering as a technique for investigation of the dynamical properties of proton conducting oxides. Currently, the main interest in these materials comes from their promise as electrolytes in future electrochemical devices and particularly through their use as electrolytes in next-generation, intermediate-temperature, fuel cells. However, the realization of such devices depends critically on the development of new, more highly proton conducting oxides. Such a development depends on increasing the current understanding of proton conduction in oxides and for this purpose quasielastic neutron scattering is an important mean. The aim of this article is to introduce the non-specialist reader to the basic principles of quasielastic neutron scattering, its advantages and disadvantages, to summarize the work that has been done on proton conducting oxides using this technique, as well as to discuss future opportunities within this field of research.
Qattan, I. A.
2017-06-01
I present a prediction of the e± elastic scattering cross-section ratio, Re+e-, as determined using a new parametrization of the two-photon exchange (TPE) corrections to electron-proton elastic scattering cross section σR. The extracted ratio is compared to several previous phenomenological extractions, TPE hadronic calculations, and direct measurements from the comparison of electron and positron scattering. The TPE corrections and the ratio Re+e- show a clear change of sign at low Q2, which is necessary to explain the high-Q2 form factors discrepancy while being consistent with the known Q2→0 limit. While my predictions are in generally good agreement with previous extractions, TPE hadronic calculations, and existing world data including the recent two measurements from the CLAS and VEPP-3 Novosibirsk experiments, they are larger than the new OLYMPUS measurements at larger Q2 values.
Towards a Resolution of the Proton Form Factor Problem: New Electron and Positron Scattering Data
Adikaram, D.; Rimal, D.; Weinstein, L. B.; Raue, B.; Khetarpal, P.; Bennett, R. P.; Arrington, J.; Brooks, W. K.; Adhikari, K. P.; Afanasev, A. V.; Amaryan, M. J.; Anderson, M. D.; Anefalos Pereira, S.; Avakian, H.; Ball, J.; Battaglieri, M.; Bedlinskiy, I.; Biselli, A. S.; Bono, J.; Boiarinov, S.; Briscoe, W. J.; Burkert, V. D.; Carman, D. S.; Careccia, S.; Celentano, A.; Chandavar, S.; Charles, G.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Dodge, G. E.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Filippi, A.; Fleming, J. A.; Fradi, A.; Garillon, B.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Goetz, J. T.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guegan, B.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Harrison, N.; Hattawy, M.; Hicks, K.; Holtrop, M.; Hughes, S. M.; Hyde, C. E.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Jenkins, D.; Jiang, H.; Jo, H. S.; Joo, K.; Joosten, S.; Kalantarians, N.; Keller, D.; Khandaker, M.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Koirala, S.; Kubarovsky, V.; Kuhn, S. E.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; Mattione, P.; Mayer, M.; McKinnon, B.; Mestayer, M. D.; Meyer, C. A.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Moody, C. I.; Moutarde, H.; Movsisyan, A.; Camacho, C. Munoz; Nadel-Turonski, P.; Niccolai, S.; Niculescu, G.; Osipenko, M.; Ostrovidov, A. I.; Park, K.; Pasyuk, E.; Peña, C.; Pisano, S.; Pogorelko, O.; Price, J. W.; Procureur, S.; Prok, Y.; Protopopescu, D.; Puckett, A. J. R.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Sharabian, Y. G.; Simonyan, A.; Skorodumina, I.; Smith, E. S.; Smith, G. D.; Sober, D. I.; Sokhan, D.; Sparveris, N.; Stepanyan, S.; Stoler, P.; Strauch, S.; Sytnik, V.; Taiuti, M.; Tian, Ye; Trivedi, A.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.; CLAS Collaboration
2015-02-01
There is a significant discrepancy between the values of the proton electric form factor, GEp, extracted using unpolarized and polarized electron scattering. Calculations predict that small two-photon exchange (TPE) contributions can significantly affect the extraction of GEp from the unpolarized electron-proton cross sections. We determined the TPE contribution by measuring the ratio of positron-proton to electron-proton elastic scattering cross sections using a simultaneous, tertiary electron-positron beam incident on a liquid hydrogen target and detecting the scattered particles in the Jefferson Lab CLAS detector. This novel technique allowed us to cover a wide range in virtual photon polarization (ɛ ) and momentum transfer (Q2) simultaneously, as well as to cancel luminosity-related systematic errors. The cross section ratio increases with decreasing ɛ at Q2=1.45 GeV2 . This measurement is consistent with the size of the form factor discrepancy at Q2≈1.75 GeV2 and with hadronic calculations including nucleon and Δ intermediate states, which have been shown to resolve the discrepancy up to 2 - 3 GeV2 .
ELECTRON SCATTERING EXPERIMENTS ON THE NEUTRON AND PROTON
Energy Technology Data Exchange (ETDEWEB)
Berkelman, Karl
1963-06-15
The electric and magnetic helicity form factors of the proton are measured at 4-momentum transfers (squared) of 25 to 45 f/sup -2/, by means of electron scattering by protons at high energies. The results are combined with other e/sup -/--p and e/sup -/--d experimental findings in order to show the proton form fuctors from 0 to 45 f/sup -2/ and the neutron form factors from 0 to 25 f/sup -2/. (T.F.H.)
Parity nonconservation in proton scattering at higher energies
International Nuclear Information System (INIS)
Mischke, R.E.
1993-01-01
A parity-nonconservation experiment in the scattering of longitudinally-polarized protons at an incident proton momentum of 6 GeV/c is examined. This experiment indicates a sharp rise with energy of the total cross section correlated with proton helicity that was unexpected. This energy dependence is due to the strong part of the interaction and may indicate the role of a diquark component in the nucleon. New experiments at higher energies are needed to confirm such a model. Future experiment can benefit from an analysis of sources of systematic error that have been encountered in the experiment discussed here
Parity nonconservation in proton scattering at higher energies
International Nuclear Information System (INIS)
Mischke, R.E.
1987-01-01
Parity-nonconservation experiments in the scattering of longitudinally-polarized protons at incident proton momenta of 1.5 GeV/c and 6 GeV/c are examined. These experiments indicate a change with energy of the total cross section correlated with proton helicity that was unexpected. This energy dependence is due to the strong part of the interaction and may indicate the role of a diquark component in the nucleon. New experiments at higher energies are needed to confirm such a model. Future experiments can benefit from an analysis of sources of systematic error that have been encountered in the experiments discussed here. 43 refs., 3 figs
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.
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; R. Carr; Nicholas Chant; Yu-Chiu Chao; Swapan Chattopadhyay; Russell Clark; Silviu Covrig; Anthony Cowley; Daniel Dale; C. 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; R. Hasty; A. 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; J. Liu; Berenice Loupias; A. Lung; Glen MacLachlan; Dominique Marchand; J.W. Martin; Kenneth McFarlane; Daniella Mckee; Robert McKeown; Fernand Merchez; Hamlet Mkrtchyan; Bryan Moffit; M. Morlet; Itaru Nakagawa; Kazutaka Nakahara; Melissa Nakos; 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; G.R. Smith; Damon Spayde; Samuel Stepanyan; Marcy Stutzman; Vincent Sulkosky; Vardan Tadevosyan; Raphael Tieulent; Jacques Van de Wiele; Willem van Oers; Eric Voutier; William Vulcan; G. Warren; S.P. Wells; Steven Williamson; S.A. Wood; Chen Yan; Junho Yun; Valdis Zeps
2005-06-01
We have measured parity-violating asymmetries in elastic electron-proton scattering over the range of momentum transfers 0.12 < Q{sup 2} < 1.0 GeV{sup 2}. These asymmetries, arising from interference of the electromagnetic and neutral weak interactions, are sensitive to strange quark contributions to the currents of the proton. The measurements were made at JLab using a toroidal spectrometer to detect the recoiling protons from a liquid hydrogen target. The results indicate non-zero, Q{sup 2} dependent, strange quark contributions and provide new information beyond that obtained in previous experiments.
Geometry Survey of the Time-of-Flight Neutron-Elastic Scattering (Antonella) Experiment
Energy Technology Data Exchange (ETDEWEB)
Oshinowo, Babatunde O. [Fermilab; Izraelevitch, Federico [Buenos Aires U.
2016-10-17
The Antonella experiment is a measurement of the ionization efficiency of nuclear recoils in silicon at low energies [1]. It is a neutron elastic scattering experiment motivated by the search for dark matter particles. In this experiment, a proton beam hits a lithium target and neutrons are produced. The neutron shower passes through a collimator that produces a neutron beam. The beam illuminates a silicon detector. With a certain probability, a neutron interacts with a silicon nucleus of the detector producing elastic scattering. After the interaction, a fraction of the neutron energy is transferred to the silicon nucleus which acquires kinetic energy and recoils. This kinetic energy is then dissipated in the detector producing ionization and thermal energy. The ionization produced is measured with the silicon detector electronics. On the other hand, the neutron is scattered out of the beam. A neutron-detector array (made of scintillator bars) registers the neutron arrival time and the scattering angle to reconstruct the kinematics of the neutron-nucleus interaction with the time-of-flight technique [2]. In the reconstruction equations, the energy of the nuclear recoil is a function of the scattering angle with respect to the beam direction, the time-of-flight of the neutron and the geometric distances between components of the setup (neutron-production target, silicon detector, scintillator bars). This paper summarizes the survey of the different components of the experiment that made possible the off-line analysis of the collected data. Measurements were made with the API Radian Laser Tracker and I-360 Probe Wireless. The survey was completed at the University of Notre Dame, Indiana, USA in February 2015.
High Precision Measurement of the Proton Elastic Form Factor Ratio at Low Q^{2}
Energy Technology Data Exchange (ETDEWEB)
Zhan, Xiaohui [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
2010-01-01
Experiment E08-007 measured the proton elastic form factor ratio μ_{p}G_{E}/G_{M} in the range of Q^{2} = 0.3-0.7(GeV/c)^{2} by recoil polarimetry. Data were taken in 2008 at the Thomas Jefferson National Accelerator Facility in Virginia, USA. A 1.2 GeV polarized electron beam was scattered off a cryogenic hydrogen target. The recoil proton was detected in the left HRS in coincidence with the elasticly scattered electrons tagged by the BigBite spectrometer. The proton polarization was measured by the focal plane polarimeter (FPP). In this low Q^{2} region, previous measurement from Jefferson Lab Hall A (LEDEX) along with various fits and calculations indicate substantial deviations of the ratio from unity. For this new measurement, the proposed statistical uncertainty (< 1%) was achieved. These new results are a few percent lower than expected from previous world data and fits, which indicate a smaller G_{Ep} at this region. Beyond the intrinsic interest in nucleon structure, the new results also have implications in determining the proton Zemach radius and the strangeness form factors from parity violation experiments.
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
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
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
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)
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
Quasiparticle-phonon coupling in inelastic proton scattering
International Nuclear Information System (INIS)
Weissbach, B.
1980-01-01
Multistep-processes in inelastic proton scattering from 89 Y are analyzed by using CCBA and DWBA on a quasiparticle phonon nuclear structure model. Indirect excitations caused by quasiparticle phonon coupling effects are found to be very important for the transition strengths and the shape of angular distributions. Core excitations are dominant for the higher order steps of the reaction. (author)
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 ...
A CGC/saturation approach for angular correlations in proton-proton scattering
Energy Technology Data Exchange (ETDEWEB)
Gotsman, E. [Tel Aviv University, Department of Particle Physics, School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of Exact Science, Tel Aviv (Israel); Levin, E. [Tel Aviv University, Department of Particle Physics, School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of Exact Science, Tel Aviv (Israel); Universidad Tecnica Federico Santa Maria, Departamento de Fisica, Valparaiso (Chile); Centro Cientifico-Tecnologico de Valparaiso, Valparaiso (Chile); Potashnikova, I. [Universidad Tecnica Federico Santa Maria, Departamento de Fisica, Valparaiso (Chile); Centro Cientifico-Tecnologico de Valparaiso, Valparaiso (Chile)
2017-09-15
We generalized our model for the description of hard processes, and calculate the value of the azimuthal angular correlations (Fourier harmonics v{sub n}), for proton-proton scattering. The energy and multiplicity independence, as well as the value of v{sub n}, turns out to be in accord with the experimental data, or slightly larger. Therefore, before making extreme assumptions on proton-proton collisions, such as the production of a quark-gluon plasma in large multiplicity events, we need to understand how these affect the Bose-Einstein correlations, which have to be taken into account since the Bose-Einstein correlations are able to describe the angular correlations in proton-proton collisions, without including final state interactions. (orig.)
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.
Collaboration, T. Csörgő for the TOTEM; :; Antchev, G.; Aspell, P.; Atanassov, I.; Avati, V.; Baechler, J.; Berardi, V.; Berretti, M.; Bossini, E.; Bozzo, M.; Brogi, P.; Brücken, E.; Buzzo, A.; Cafagna, F. S.
2012-01-01
Proton-proton elastic scattering has been measured by the TOTEM experiment at the CERN Large Hadron Collider at $\\sqrt{s} = 7 $ TeV in special runs with the Roman Pot detectors placed as close to the outgoing beam as seven times the transverse beam size. The differential cross-section measurements are reported in the |t|-range of 0.36 to 2.5 GeV^2. Extending the range of data to low t values from 0.02 to 0.33 GeV^2,and utilizing the luminosity measurements of CMS, the total proton-proton cros...
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...
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
Parity violation in proton-proton scattering at 230 MEV
International Nuclear Information System (INIS)
Birchall, J.; Bowman, J.D.; Davis, C.A.
1988-01-01
Below /similar to/300 MeV six meson-nucleon coupling strengths are required to describe the weak interaction of nucleons. Many experiments have found parity-violating effects in nuclear systems, but only four significant, independent constraints exist. A new measurement is proposed where measurable effects are predicted with minimal dependence on nuclear interaction models, yielding information complementary to previous results. This is a measurement of the parity-violating analyzing power. A/sub z/ in p-p scattering at 230 MeV, which is shown to be sensitive to the weak rho-nucleon coupling. This measurement, at a precision of +- 2 x 10/sup -8/, together with a proposed measurement by the University of Washington group at I.L.L. of the parity-violating neutron spin rotation, will provide the fifth and sixth independent constraints needed to determine the weak meson-nucleon coupling constants
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
Cross section measurements of the elastic electron - deuteron scattering at MAMI
Energy Technology Data Exchange (ETDEWEB)
Kohl, Yvonne [Universitaet Mainz, Institut fuer Kernphysik (Germany); Collaboration: A1-Collaboration
2015-07-01
The electromagnetic form factors of light nuclei provide a sensitive test of our understanding of nuclei. Because the deuteron has spin one, three form factors are needed to fully describe the electromagnetic structure of the deuteron. Especially the deuteron charge radius is a favourite observable to compare experiment and calculation. Recently, an extensive measurement campaign has been performed at MAMI (Mainzer Microtron) to determine the deuteron charge radius using elastic electron scattering - with the aim to halve the error compared to previous such experiments. The experiment took place at the 3-spectrometer facility of the A1-collaboration. Cross section measurements of the elastic electron-deuteron scattering have been performed for 180 different kinematic settings in the low momentum transfer region. From these, the charge form factor can precisely be determined. Fitting the form factor with an appropiate fit function, the radius can then be determined from the slope at zero momentum transfer. The determined radius could then be used as a counterweight to the value obtained from the advanced atomic Lamb shift measurements, thus providing additional insight to the proton radius puzzle.
Triple parton scatterings in high-energy proton-proton collisions arXiv
d'Enterria, David
2017-01-01
A generic expression to compute triple parton scattering cross sections in high-energy proton-proton (pp) collisions is presented as a function of the corresponding single parton cross sections and the transverse parton profile of the proton encoded in an effective parameter σeff,TPS. The value of σeff,TPS is closely related to the similar effective cross section that characterizes double parton scatterings, and amounts to σeff,TPS=12.5±4.5 mb. Estimates for triple charm (cc¯) and bottom (bb¯) production in pp collisions at LHC and FCC energies are presented based on next-to-next-to-leading-order perturbative calculations for single cc¯, bb¯ cross sections. At s≈100 TeV, about 15% of the pp collisions produce three cc¯ pairs from three different parton-parton scatterings.
Study of forward elastic pp scattering at √ s = 8 TeV with the ALFA detector
DEFF Research Database (Denmark)
Stark, Simon Holm
The elastic proton-proton scattering data analyzed in this thesis was taken at the LHC with the ALFA detector at sqrt(s) = 8 TeV with a beta* collision optics which gave access to the Coulomb-Nuclear-Interference region. An improved procedure was used to fit the observed number of elastic events......_tot, and the ratio of the real to imaginary forward elastic scattering amplitude, rho, are: sigma_tot = 99.1 +/- 0.3 (stat.) +/- 1.6 (syst.) mb rho = 0.166 +/- 0.017 (stat.) +/- 0.019 (syst.) which are in agreement with previous measurements. As part of the analysis, the detector distance to the beam was determined...... with an improved method. A new background estimation procedure was developed and also implemented in the determination of the elastic track reconstruction efficiency. The experience gained in this thesis was used to optimize the experimental settings for a new data taking at sqrt(s) = 13 TeV with beta* = 2.5 km...
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
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.)
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
EDS'09: 13th International Conference on Elastic & Diffractive Scattering
CERN. Geneva
2009-01-01
The series of International Conferences on Elastic and Diffractive Scattering was founded in 1985 in the picturesque old French town of Blois, famous for its XIV - XVIIth century château, inside of which the first meeting took place. Since then, meetings have been organised every two years in different places of the world: New York (1987), Evanston (1989), Isola d'Elba (1991), Providence (1993), Blois (1995), Seoul (1997), Protvino (1999), Prague (2001), Helsinki (2003), Blois (2005) and Hamburg (2007). The conference will focus on the most recent experimental and theoretical results in particle physics with an emphasis on Quantum Chromodynamics (QCD). http://cern.ch/eds09/ The conference agenda is now full. No further contributions can be accepted.
Scattering phase shift for elastic two pion scattering and the rho resonance in lattice QCD
Energy Technology Data Exchange (ETDEWEB)
Gutzwiller, Simone
2012-10-08
In this thesis we use lattice QCD to compute scattering phase shifts for elastic two-pion scattering in the isospin I=1 channel. Using Luescher's formalism, we derive the scattering phase shifts for different total momenta of the two-pion system in a non-rest frame. Furthermore we analyse the symmetries of the non-rest frame lattices and construct 2-pion and rho operators transforming in accordance with these symmetries. The data was collected for a 32{sup 3} x 64 and a 40{sup 3} x 64 lattice with N{sub f}=2 clover improved Wilson fermions at a pion mass around 290 MeV and a lattice spacing of about 0.072 fm.
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.
Neutron-Proton Scattering Experiments at ANKE-COSY
Kacharava, A.; Chiladze, D.; Chiladze, B.; Keshelashvili, I.; Lomidze, N.; Macharashvili, G.; McHedlishvili, D.; Nioradze, M.; Rathmann, F.; Ströher, H.; Wilkin, C.
2010-04-01
The nucleon-nucleon interaction (NN) is fundamental for the whole of nuclear physics and hence to the composition of matter as we know it. It has been demonstrated that stored, polarised beams and polarised internal targets are experimental tools of choice to probe spin effects in NN-scattering experiments. While the EDDA experiment has dramatically improved the proton-proton date base, information on spin observables in neutron-proton scattering is very incomplete above 800 MeV, resulting in large uncertainties in isoscalar n p phase shifts. Experiments at COSY, using a polarised deuteron beam or target, can lead to significant improvements in the situation through the study of quasi-free reactions on the neutron in the deuteron. Such a measurements has already been started at ANKE by using polarised deuterons on an unpolarised target to study the dp → ppn deuteron charge-exchange reaction and the full program with a polarised storage cell target just has been conducted. At low excitation energies of the final pp system, the spin observables are directly related to the spin- dependent parts of the neutron-proton charge-exchange amplitudes. Our measurement of the deuteron-proton spin correlations will allow us to determine the relative phases of these amplitudes in addition to their overall magnitudes.
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
Measurement of charge symmetry breaking in np elastic scattering at 350 MeV
International Nuclear Information System (INIS)
Abegg, R.; Berdoz, A.R.; Birchall, J.
1994-10-01
TRIUMF experiment 369, a measurement of charge symmetry breaking in np elastic scattering at 350 MeV, has completed data taking. Scattering asymmetries were measured with a polarized (unpolarized) neutron beam incident on an unpolarized (polarized) frozen spin target. Coincident scattered neutrons and recoil protons were detected by a mirror symmetric detection system in the center-of-mass angle range from 50 deg - 90 deg. A preliminary result for the difference of the zero-crossing angles, where analyzing powers cross zero, is Δθ cm = 0.445 deg ± 0.054 deg (stat.) ± 0.051 deg (syst.) based on fits over the angle range 53.4 deg ≤ θ cm ≤ 86.9 deg. The difference of the analyzing powers ΔA ≡ A n - A p , where the subscripts denote polarized nucleons, was deduced with dA/dθ cm = (-1.35 ± 0.05) x 10 -2 deg -1 to be [60 ± 7(stat.) ± 7(syst.) ± 2(syst.)] x 10 -4 . (author). 11 refs., 6 figs
Experimental study of inclusive deep inelastic neutrino--proton scattering
International Nuclear Information System (INIS)
Berge, J.P.; Bogert, D.; DiBianca, F.A.; Cundy, D.C.; Dunaitsev, A.; Efremenko, V.; Ermolov, P.; Fowler, W.; Hanft, R.; Harigel, G.; Huson, F.R.; Kolganov, V.; Mukhin, A.; Nezrick, F.A.; Rjabov, Y.; Scott, W.G.; Smart, W.; Coffin, C.T.; Diamond, R.N.; French, H.; Louis, W.; Roe, B.P.; Seidl, A.A.; Velde, J.C.V.
1976-01-01
A neutrino--proton scattering experiment has been performed at Fermilab by using a wide-band horn-focused neutrino beam and the 15-ft bubble chamber filled with hydrogen. For the inclusive reaction ν/sub μ/ + p → μ - + hadrons, the mean value of Q 2 is found to increase linearly with energy, as is expected from Bjorken scaling, and a fit to the data gives 2 > = (0.18 +- 0.01) E. The distribution in the Bjorken scaling variable x shows evidence for deviations from predictions based on electron-scattering data and the quark-parton model
Polarization transfer in elastic p-d scattering at E sub. rho. = 22. 7 MeV
Energy Technology Data Exchange (ETDEWEB)
Gruebler, W.; Clajus, M.; Egun, P.M.; Hautle, P.; Weber, A. (Eidgenoessische Technische Hochschule, Zurich (CH). Inst. fuer Mittelenergiephysik); Schmelzbach, P.A. (Paul Scherrer Inst. (PSI), Villigen (CH)); Slaus, I. (Institut Ruder Boskovic, Zagreb. (YU)); Vuaridel, B. (Michigan Univ., Ann Arbor, MI (US)); Sperisen, F. (Indiana Univ. Cyclotron Facility, Bloomington, IN (US)); Kretschmer, W.; Karschnick, R.O.; Rauscher, A.; Weidmann, R.; Walter, T. (Erlangen-Nuernberg Univ., Erlangen (DE). Physikalisches Inst.); Bruno, M.; Cannata, F.; d' Agostino, M. (Istituto Nazionale di Fisica Nucleare, Bologna (IT))
1990-11-15
The proton-deuteron elastic scattering has been investigated at E{sub p}=22.7 MeV by comparison of rigorous Faddeev calculations with experimental results. From the calculations it was found that polarization transfer coefficients are more sensitive to details of the nucleon-nucleon potentials than the analyzing powers. Therefore we measured the proton to proton transfer coefficients K{sup y'}{sub y} and K{sup x'}{sub z}. The observable most sensitive to the tensor force is K{sup y'}{sub y}. The angular distributions of K{sup y'}{sub y} and, to a smaller extent, K{sup x'}{sub z} clearly favour the Bonn A potential.
Model independent dispersion approach to proton Compton scattering
International Nuclear Information System (INIS)
Caprini, I.; Radescu, E.E.
1980-12-01
The proton Compton scattering at low and intermediate energies is studied by means of a dispersion framework which exploits in an optimal way the (fixed momentum transfer) analyticity properties of the amplitudes in conjunction with the consequences of the (s-channel) unitarity. The mathematical background of the work consists of methods specific to boundary value problems for analytic vector-valued functions and interpolation theory. In comparison with previous related work, the external problems to be solved now are much more difficult because of the inclusion of the photoproduction input and also lead to additional computational complications. The lower bounds on the differential cross-section, obtained without any reference to subtractions and annihilation channel contributions, appear sufficiently restrictive to evidentiate rigorously some inconsistencies between results of single pion photoproduction multipole extractions and proton Compton scattering data. (author)
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
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.
International Nuclear Information System (INIS)
Sonika; Roy, B.J.; Parmar, A.; Jha, V.; Pal, U.K.; Pandit, S.K.; Parkar, V.V.; Ramachandran, K.; Mahata, K.; Pal, A.; Santra, S.; Mohanty, A.K.; Sinha, T.; Parihari, A.
2014-01-01
Measurement and detailed analysis of elastic scattering and inelastic excitations in 206 Pb( 18 O, 18 O) have been reported here. First, the elastic scattering cross-section was calculated with a bare double folded real potential. The DF potential consists of folding of a harmonic oscillator density distribution to simulate 18 O with the sum of two Fermi density distributions for the proton and neutron in 206 Pb with correct normalizations. Our measured higher energy data for the same system was first analyzed with this DF potential
Energy Technology Data Exchange (ETDEWEB)
Saleem, M.; Fazal-e-Aleem; Rifique, M.
1987-03-01
The recent experimental measurements for anti-pp and ..cap alpha cap alpha.. elastic scattering at high energies have shown that the Chou-Yang conjecture regarding the relationship between the electromagnetic and the hadronic form factor of a particle is only an approximation. A new ansatz has been proposed to obtain hadronic form factors of proton and the ..cap alpha..-particle. These form factors have been used to explain the various characteristics of anti-pp, ..cap alpha cap alpha.. and p..cap alpha.. elastic scattering at high energies.
Neutron–Proton Scattering Experiments at ANKE–COSY
Directory of Open Access Journals (Sweden)
Rathmann F.
2010-04-01
Full Text Available The nucleon–nucleon interaction (NN is fundamental for the whole of nuclear physics and hence to the composition of matter as we know it. It has been demonstrated that stored, polarised beams and polarised internal targets are experimental tools of choice to probe spin eﬀects in NN–scattering experiments. While the EDDA experiment has dramatically improved the proton–proton date base, information on spin observables in neutron–proton scattering is very incomplete above 800 MeV, resulting in large uncertainties in isoscalar n p phase shifts. Experiments at COSY, using a polarised deuteron beam or target, can lead to signiﬁcant improvements in the situation through the study of quasi–free reactions on the neutron in the deuteron. Such a measurements has already been started at ANKE by using polarised deuterons on an unpolarised target to study the dp → {pp}n deuteron charge–exchange reaction and the full program with a polarised storage cell target just has been conducted. At low excitation energies of the ﬁnal pp system, the spin observables are directly related to the spin– dependent parts of the neutron–proton charge–exchange amplitudes. Our measurement of the deuteron–proton spin correlations will allow us to determine the relative phases of these amplitudes in addition to their overall magnitudes.
Characterization of solar cell materials by Proton Back Scattering Spectroscopy
International Nuclear Information System (INIS)
Joynal Abedin, M.; Fazlul Hoque, A.K.M.; Firoz Hasan, S.M.
2001-01-01
The need for accurate chemical characterization of samples specially related to electronic and solar cell materials has assumed increasing importance in recent years. The importance of the study of the surfaces of materials of different origin also increased in recent years to a great extent. This need has created a worldwide spurt to develop rapid, accurate and sensitive tools for the characterization of materials. In recent years the proton backscattering spectrometry (PBS) method has been recognized as one of the useful analytical tool in several applications of material analysis and technology. The lack of information of the relevant scattering cross sections as a function of proton energy and the problems arising in conventional data analysis have so far rendered proton backscattering analysis of multielemental samples difficult at low energies. On the other hand advances in the computer evaluation of experimental data have, however, made it possible to utilize low-MeV protons as a sensitive probe for light elements in the μm range. The benefits of the method in comparison to alpha particle backscattering include the relatively higher non-Rutherford scattering cross sections of the light elements and to the lower proton stopping in the target material. These lead to higher sensitivity in detecting and profiling light elements in heavy targets and to significantly larger accessible depths and smaller straggling than with alpha particles. Research works on the development of methodologies of Proton Backscattering Spectrometry (PBS) for the analysis of thin films and surfaces has been in progress in the 3 MeV Van de Graaff Accelerator facilities of Atomic Energy Centre, Dhaka for some years. The PBS system comprises a target chamber with appropriate sample holders and a Surface Barrier Detector (SBD) with the associated electronics for data acquisition and reduction. For the evaluation of the PBS data RBS Universal Master Package, RUMP has been installed in the
Signature for g bosons from medium energy proton scattering experiments
International Nuclear Information System (INIS)
Kuyucak, S.
1993-01-01
We apply the recently developed algebraic (1/N expansion) scattering formalism to medium energy proton scattering from 154 Sm and 176 Yb. The nuclear structure effects in this formalism are described by the interacting boson model generalized to arbitrary interactions and types of bosons i.e. s,d,g, etc. We find that, in the sd boson model, a consistent description of cross sections is possible only for the 0 + and 2 + states. The failure of the model with regard to the 4 + states indicates that the effective hexadecapole operator used in the sd model is inadequate. In contrast, the data for scattering to the 0 + , 2 + and 4 + states could be consistently described in the sdg boson model. The spectroscopic data for the low-lying levels usually can not distinguish between the sd and sdg models due to renormalization of parameters, and one has to look at high spin or energy data for evidence of g bosons. The inelastic proton scattering experiments, on the other hand, directly probe the wave functions, and hence could provide a signature for g bosons even in the ground band states
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
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.
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
Elastic and Proton-Dissociative Photoproduction of J/psi Mesons at HERA
Alexa, C.; Baghdasaryan, A.; Baghdasaryan, S.; Bartel, W.; Begzsuren, K.; Belousov, A.; Belov, P.; Boudry, V.; Bozovic-Jelisavcic, I.; Brandt, G.; Brinkmann, M.; Brisson, V.; Britzger, D.; Buniatyan, A.; Bylinkin, A.; Bystritskaya, L.; Campbell, A.J.; Cantun Avila, K.B.; Ceccopieri, F.; Cerny, K.; Chekelian, V.; Contreras, J.G.; Cvach, J.; Dainton, J.B.; Daum, K.; De Wolf, E.A.; Diaconu, C.; Dobre, M.; Dodonov, V.; Dossanov, A.; Eckerlin, G.; Egli, S.; Elsen, E.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Fischer, D.J.; Fleischer, M.; Fomenko, A.; Gabathuler, E.; Gayler, J.; Ghazaryan, S.; Glazov, A.; Goerlich, L.; Gogitidze, N.; Gouzevitch, M.; Grab, C.; Grebenyuk, A.; Greenshaw, T.; Grindhammer, G.; Habib, S.; Haidt, D.; Henderson, R.C.W.; Hennekemper, E.; Herbst, M.; Herrera, G.; Hildebrandt, M.; Hiller, K.H.; Hladky, J.; Hoffmann, D.; Horisberger, R.; Hreus, T.; Huber, F.; Jacquet, M.; Janssen, X.; Jonsson, L.; Jung, H.; Kapichine, M.; Kiesling, C.; Klein, M.; Kleinwort, C.; Kogler, R.; Kostka, P.; Kramer, M.; Kretzschmar, J.; Kruger, K.; Landon, M.P.J.; Lange, W.; Laycock, P.; Lebedev, A.; Levonian, S.; Lipka, K.; List, B.; List, J.; Lobodzinski, B.; Lopez-Fernandez, R.; Lubimov, V.; Malinovski, E.; Martyn, H.U.; Maxfield, S.J.; Mehta, A.; Meyer, A.B.; Meyer, H.; Meyer, J.; Mikocki, S.; Milcewicz-Mika, I.; Morozov, A.; Morris, J.V.; Muller, K.; Naumann, Th.; Newman, P.R.; Niebuhr, C.; Nikitin, D.; Nowak, G.; Nowak, K.; Olsson, J.E.; Ozerov, D.; Pahl, P.; Palichik, V.; Pandurovic, M.; Pascaud, C.; Patel, G.D.; Perez, E.; Petrukhin, A.; Picuric, I.; Pirumov, H.; Pitzl, D.; Placakyte, R.; Pokorny, B.; Polifka, R.; Radescu, V.; Raicevic, N.; Ravdandorj, T.; Reimer, P.; Rizvi, E.; Robmann, P.; Roosen, R.; Rostovtsev, A.; Rotaru, M.; Ruiz Tabasco, J.E.; Rusakov, S.; Salek, D.; Sankey, D.P.C.; Sauter, M.; Sauvan, E.; Schmitt, S.; Schoeffel, L.; Schoning, A.; Schultz-Coulon, H.C.; Sefkow, F.; Shushkevich, S.; Soloviev, Y.; Sopicki, P.; South, D.; Spaskov, V.; Specka, A.; Staykova, Z.; Steder, M.; Stella, B.; Stoicea, G.; Straumann, U.; Sykora, T.; Thompson, P.D.; Traynor, D.; Truol, P.; Tsakov, I.; Tseepeldorj, B.; Turnau, J.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Vazdik, Y.; Wegener, D.; Wunsch, E.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zlebcik, R.; Zohrabyan, H.; Zomer, F.
2013-06-15
Cross sections for elastic and proton-dissociative photoproduction of J/psi mesons are measured with the H1 detector in positron-proton collisions at HERA. The data were collected at $ep$ centre-of-mass energies sqrt{s} approx 318 GeV and sqrt{s} approx 225 GeV, corresponding to integrated luminosities of L = 130 pb^{-1} and L = 10.8 pb^{-1}, respectively. The cross sections are measured as a function of the photon-proton centre-of-mass energy in the range 25< Wgp < 110 GeV. Differential cross sections $\\mathrm{d}\\sigma / \\mathrm{d}t$, where $t$ is the squared four-momentum transfer at the proton vertex, are measured in the range $|t| < 1.2 \\, \\gevsq$ for the elastic process and $|t| < 8 \\, \\gevsq$ for proton dissociation. The results are compared to other measurements. The $\\Wgp$ and $t$-dependences are parametrised using phenomenological fits.
Elastic electron scattering from 14N, 15N, 16O and 18O at small momentum transfer
International Nuclear Information System (INIS)
Schuetz, W.
1973-01-01
At the Darmstadt linear accelerator, cross-sections for the elastic scattering of electrons on 14 N and 16 O relative to the proton and on 15 N and 18 O relative to 14 N and 16 O were measured at energies 30 MeV 0 0 (q 2 -2 ). The experiments were done with gas targets, the target containers being thin-walled aluminium cylinders. The data were evaluated by means of the partial-wave method assuming a charge distribution according to the shell model. (orig./WL) [de
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.)
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
Energy Technology Data Exchange (ETDEWEB)
Kennedy, Robert D. [UC, San Diego
1992-01-01
The ratio of the neutron and proton structure functions $F_2$ has been measured to very low $X_{bj}$ using inelastic muon scattering. Data were taken in 1990 using 475 GeV muons incident on hydrogen and deuterium targets. Electromagnetic calorimetry has been used to remove radiative backgrounds and muon-electron elastic scattering. Results of the measurement are presented which cover the kinematic region 0.0001 $\\le$ $X_{bj} \\le$ 0.4 and 0.1 GeV$^2$ /$c^2$ $\\le$ $Q^2$ $\\le$ 100.0 GeV$^2$ /c$^2$.
Energy Technology Data Exchange (ETDEWEB)
Falk-Vairant, P; Valladas, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1961-07-01
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) [French] On presente brievement les donnees connues concernant la section efficace totale pour la diffusion des mesons pi par les protons dans le domaine d'energie de 400 MeV a 1,5 GeV. On a egalement rassemble tous les resultats concernant les sections efficaces totales pour des canaux particuliers: diffusion elastique, diffusion inelastique et echange de charge. En partant des nouveaux resultats sur la section efficace pour la diffusion elastique et inelastique dans l'etat T = 1/2. (auteurs)
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
International Nuclear Information System (INIS)
Pierrard, J.; Bruneton, C.; Bystricky, J.; Cozzika, G.; Deregel, J.; Ducros, Y.; Gaidot, A.; Khantine-Langlois, F.; Lehar, F.; Lesquen, A. de; Merlo, J.P.; Miyashita, S.; Movchet, J.; Raoul, J.C.; Van Rossum, L.; Kanavets, V.P.
1975-01-01
The spin rotation parameter R in pp and π + p elastic scattering at 45GeV/c has been measured at the Serpukhov accelerator, for /t/ ranging from 0.2 to 0.5(GeV/c) 2 . The results are presented, together with previous R measurements at 3.8, 6, 16 and 40GeV/c, and are compared with the predictions of Regge pole models. The equality of the values for R in proton-proton and pion-proton scattering, within the experimental errors, is a test of factorization of the residues. An s-channel helicity amplitude analysis for pion-nucleon scattering at 40GeV/c is made using all available data. Significant results are obtained for the non flip amplitude in isoscalar exchange and for flip amplitudes on both isovector and isoscalar exchanges. The helicity flip in isoscalar exchange is non negligible. The energy dependence of this amplitude, at 6, 16 and 40GeV/c, is compared with predictions of Regge pole models [fr
Nuclear spin response studies in inelastic polarized proton scattering
International Nuclear Information System (INIS)
Jones, K.W.
1988-01-01
Spin-flip probabilities S/sub nn/ have been measured for inelastic proton scattering at incident proton energies around 300 MeV from a number of nuclei. At low excitation energies S/sub nn/ is below the free value. For excitation energies above about 30 MeV for momentum transfers between about 0.35 fm/sup /minus/1/ and 0.65 fm/sup / minus/1/ S/sub nn/ exceeds free values significantly. These results suggest that the relative ΔS = 1(ΔS = 0 + ΔS = 1) nuclear spin response approaches about 90% in the region of the enhancement. Comparison of the data with slab response calculations are presented. Decomposition of the measured cross sections into σ(ΔS = 0) and σ(ΔS = 1) permit extraction of nonspin-flip and spin-flip dipole and quadrupole strengths. 29 refs., 11 figs
Precocious scaling in antiproton-proton scattering at low energies
International Nuclear Information System (INIS)
Ion, D.B.; Petrascu, C.; Topor Pop, V.; Popa, V.
1993-08-01
The scaling of the diffraction peak in antiproton-proton scattering has been investigated from nera threshold up to 3 GeV/c laboratory momenta. It was shown that the scaling of the differential cross sections are evidentiated with a surprising accuracy not only at high energies, but also at very low ones (e.g. p LAB = 0.1 - 0.5 GeV/c), beyond the resonance and exotic resonance regions. This precocious scaling strongly suggests that the s-channel helicity conservation (SCHC) can be a peculiar property that should be tested in antiproton-proton interaction not only at high energies but also at low energy even below p LAB = 1 GeV/c. (author). 36 refs, 9 figs
Energy Technology Data Exchange (ETDEWEB)
Park, Yang-Kyun, E-mail: ykpark@mgh.harvard.edu; Sharp, Gregory C.; Phillips, Justin; Winey, Brian A. [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114 (United States)
2015-08-15
Purpose: To demonstrate the feasibility of proton dose calculation on scatter-corrected cone-beam computed tomographic (CBCT) images for the purpose of adaptive proton therapy. Methods: CBCT projection images were acquired from anthropomorphic phantoms and a prostate patient using an on-board imaging system of an Elekta infinity linear accelerator. Two previously introduced techniques were used to correct the scattered x-rays in the raw projection images: uniform scatter correction (CBCT{sub us}) and a priori CT-based scatter correction (CBCT{sub ap}). CBCT images were reconstructed using a standard FDK algorithm and GPU-based reconstruction toolkit. Soft tissue ROI-based HU shifting was used to improve HU accuracy of the uncorrected CBCT images and CBCT{sub us}, while no HU change was applied to the CBCT{sub ap}. The degree of equivalence of the corrected CBCT images with respect to the reference CT image (CT{sub ref}) was evaluated by using angular profiles of water equivalent path length (WEPL) and passively scattered proton treatment plans. The CBCT{sub ap} was further evaluated in more realistic scenarios such as rectal filling and weight loss to assess the effect of mismatched prior information on the corrected images. Results: The uncorrected CBCT and CBCT{sub us} images demonstrated substantial WEPL discrepancies (7.3 ± 5.3 mm and 11.1 ± 6.6 mm, respectively) with respect to the CT{sub ref}, while the CBCT{sub ap} images showed substantially reduced WEPL errors (2.4 ± 2.0 mm). Similarly, the CBCT{sub ap}-based treatment plans demonstrated a high pass rate (96.0% ± 2.5% in 2 mm/2% criteria) in a 3D gamma analysis. Conclusions: A priori CT-based scatter correction technique was shown to be promising for adaptive proton therapy, as it achieved equivalent proton dose distributions and water equivalent path lengths compared to those of a reference CT in a selection of anthropomorphic phantoms.
Measurement of proton-proton inelastic scattering cross-section at $\\sqrt{s}$= 7 TeV
Antchev, G; Atanassov, I.; Avati, V.; Baechler, J.; Berardi, V.; Berretti, M.; Bossini, E.; Bozzo, M.; Brogi, P.; Brücken, E.; Buzzo, A.; Cafagna, F.S.; Calicchio, M.; Catanesi, M.G.; Covault, C.; Csanad, M.; Csörgö, T.; Deile, M.; Doubek, M.; Eggert, K.; Eremin, V.; Ferretti, R.; Ferro, F.; Fiergolski, A.; Garcia, F.; Giani, S.; Greco, V.; Grzanka, L.; Heino, J.; Hilden, T.; Intonti, R.A.; Kaspar, J.; Kopal, J.; Kundrat, V.; Kurvinen, K.; Lami, S.; Latino, G.; Lauhakangas, R.; Leszko, T.; Lippmaa, E.; Lokajicek, M.; Lo Vetere, M.; Lucas Rodriguez, F.; Macri, M.; Mäki, T.; Mercadante, A.; Minafra, N.; Minutoli, S.; Nemes, F.; Niewiadomski, H.; Oliveri, E.; Oljemark, F.; Orava, R.; Oriunno, M.; Österberg, K.; Palazzi, P.; Prochazka, J.; Quinto, M.; Radermacher, E.; Radicioni, E.; Ravotti, F.; Robutti, E.; Ropelewski, L.; Ruggiero, G.; Saarikko, H.; Santroni, A.; Scribano, A.; Smajek, J.; Snoeys, W.; Sziklai, J.; Taylor, C.; Turini, N.; Vacek, V.; Vitek, M.; Welti, J.; Whitmore, J.; Wyszkowski, P.
2013-01-01
The TOTEM experiment at the LHC has measured the inelastic proton-proton cross-section at $\\sqrt{s}$ = 7 TeV in a β* = 90 m run with low inelastic pile-up. The measurement was based on events with at least one charged particle in the T2 telescope acceptance of 5.3 < |η| < 6.5 in pseudorapidity. Combined with data from the T1 telescope, covering 3.1 < |η| < 4.7, the cross-section for inelastic events with at least one |η| < 6.5 final state particle was determined to be 70.5 2.9 mb. Based on models for low mass diffraction, the total inelastic cross-section was deduced to be 73.7 3.4 mb. An upper limit of 6.31 mb at 95 % confidence level on the cross-section for events with diffractive masses below 3.4 GeV was obtained from the difference between the overall inelastic cross-section obtained by TOTEM using elastic scattering and the cross-section for inelastic events with at least one |η| < 6.5 final state particle.
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
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.)
An analytic distorted wave approximation for intermediate energy proton scattering
International Nuclear Information System (INIS)
Di Marzio, F.; Amos, K.
1982-01-01
An analytic Distorted Wave approximation has been developed for use in analyses of intermediate energy proton inelastic scattering from nuclei. Applications are made to analyse 402 and 800 MeV data from the isoscalar and isovector 1 + and 2 + states in 12 C and to the 800 MeV data from the excitation of the 2 - (8.88MeV) state in 16 O. Comparisons of predictions made using different model two-nucleon t-matrices and different models of nuclear structure are given
Scattering of polarized protons by yttrium, iron and nickel nuclei
International Nuclear Information System (INIS)
Melssen, J.P.M.G.
1978-01-01
Results are presented of scattering experiments performed on yttrium and some iron and nickel isotopes with polarized proton beams at energies around 20 MeV. The angular distributions of the differential cross sections and analyzing powers have been measured and comparison of these with predictions from theoretical models has led to information about excited nuclear states like spin, parity and details of the wavefunctions. The DWBA has been mostly used to describe the reaction at the bombarding energies and for the target nuclei investigated. (C.F.)
Diffractive Deep-Inelastic Scattering with a Leading Proton at HERA
Aktas, A.; Andreev, V.; Anthonis, T.; Antunovic, B.; Aplin, S.; Asmone, A.; Astvatsatourov, A.; Babaev, A.; Backovic, S.; Baghdasaryan, A.; Baranov, P.; Barrelet, E.; Bartel, W.; Baudrand, S.; Baumgartner, S.
2006-01-01
The cross section for the diffractive deep-inelastic scattering process $ep \\to e X p$ is measured, with the leading final state proton detected in the H1 Forward Proton Spectrometer. The data analysed cover the range \\xpom
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
Resonance scattering of 12C nuclei on protons in the Maya active target
Khodery, Mohammad
This work is related to the realm of exotic nuclei. These are nuclei that exist far from the valley of stability. Study of these nuclei introduced many interesting phenomena and changed our understanding about the nuclear structure. As exotic nuclei are very short lived, their study has to be at the time of their production using radioactive beams of the exotic nuclei. The goal of the experiment was to study the $^{13}$Be low-lying energy levels. The experiment was performed at ISOLDE at CERN as $^{12}$Be beams are produced at this facility with suitable intensity and energy. The method used to study $^{13}$Be was elastic resonance reactions. This is a powerful tool to study unbound states. This thesis concentrates on the $^{12}$C nuclei that are present in the beam as isobaric contamination. $^{12}$C in the beam is scattered on the protons which is the target. The protons are introduced in the form of isobutene gas. The aim of this work is to prove the principle of the technique of elastic resonance scatteri...
Elastic and proton-dissociative photoproduction of J/ψ mesons at HERA
International Nuclear Information System (INIS)
Alexa, C.; Dobre, M.; Rotaru, M.; Stoicea, G.; Andreev, V.; Belousov, A.; Fomenko, A.; Gogitidze, N.; Lebedev, A.; Malinovski, E.; Rusakov, S.; Vazdik, Y.; Baghdasaryan, A.; Baghdasaryan, S.; Zohrabyan, H.; Bartel, W.; Belov, P.; Brinkmann, M.; Britzger, D.; Campbell, A.J.; Eckerlin, G.; Elsen, E.; Felst, R.; Fischer, D.J.; Fleischer, M.; Gayler, J.; Ghazaryan, S.; Glazov, A.; Gouzevitch, M.; Grebenyuk, A.; Habib, S.; Haidt, D.; Kleinwort, C.; Kraemer, M.; Krueger, K.; Levonian, S.; Lipka, K.; List, B.; List, J.; Lobodzinski, B.; Meyer, A.B.; Meyer, J.; Niebuhr, C.; Olsson, J.E.; Ozerov, D.; Pahl, P.; Petrukhin, A.; Pitzl, D.; Placakyte, R.; Radescu, V.; Schmitt, S.; Sefkow, F.; Shushkevich, S.; South, D.; Steder, M.; Wuensch, E.; Begzsuren, K.; Ravdandorj, T.; Tseepeldorj, B.; Boudry, V.; Specka, A.; Bozovic-Jelisavcic, I.; Pandurovic, M.; Brandt, G.; Brisson, V.; Jacquet, M.; Pascaud, C.; Zhang, Z.; Zomer, F.; Buniatyan, A.; Huber, F.; Pirumov, H.; Sauter, M.; Schoening, A.; Bylinkin, A.; Bystritskaya, L.; Fedotov, A.; Lubimov, V.; Rostovtsev, A.; Cantun Avila, K.B.; Contreras, J.G.; Ruiz Tabasco, J.E.; Ceccopieri, F.; Wolf, E.A. de; Favart, L.; Hreus, T.; Janssen, X.; Roosen, R.; Staykova, Z.; Mechelen, P. van; Cerny, K.; Pokorny, B.; Polifka, R.; Salek, D.; Valkarova, A.; Zacek, J.; Zlebcik, R.; Chekelian, V.; Grindhammer, G.; Kiesling, C.; Cvach, J.; Hladky, J.; Reimer, P.; Zalesak, J.; Dainton, J.B.; Gabathuler, E.; Greenshaw, T.; Klein, M.; Kretzschmar, J.; Laycock, P.; Maxfield, S.J.; Mehta, A.; Patel, G.D.; Daum, K.; Meyer, H.; Diaconu, C.; Hoffmann, D.; Sauvan, E.; Vallee, C.; Dodonov, V.; Dossanov, A.; Egli, S.; Hildebrandt, M.; Horisberger, R.; Feltesse, J.; Perez, E.; Schoeffel, L.; Ferencei, J.; Goerlich, L.; Mikocki, S.; Milcewicz-Mika, I.; Nowak, G.; Sopicki, P.; Turnau, J.; Grab, C.; Henderson, R.C.W.; Hennekemper, E.; Herbst, M.; Schultz-Coulon, H.C.; Herrera, G.; Lopez-Fernandez, R.; Hiller, K.H.; Kostka, P.; Lange, W.; Naumann, T.; Joensson, L.; Jung, H.; Kapichine, M.; Morozov, A.; Nikitin, D.; Palichik, V.; Spaskov, V.; Kogler, R.; Nowak, K.; Landon, M.P.J.; Rizvi, E.; Traynor, D.; Martyn, H.U.; Morris, J.V.; Sankey, D.P.C.; Mueller, K.; Robmann, P.; Straumann, U.; Truoel, P.; Newman, P.R.; Thompson, P.D.; Picuric, I.; Raicevic, N.; Soloviev, Y.; Stella, B.; Sykora, T.; Tsakov, I.; Wegener, D.
2013-01-01
Cross sections for elastic and proton-dissociative photoproduction of J/ψ mesons are measured with the H1 detector in positron-proton collisions at HERA. The data were collected at ep centre-of-mass energies √(s) ∼ 318 GeV and √(s) ∼ 225 GeV, corresponding to integrated luminosities of L = 130 pb -1 and L = 10.8 pb -1 , respectively. The cross sections are measured as a function of the photon-proton centre-of-mass energy in the range 25 γp 2 for the elastic process and vertical stroke t vertical stroke 2 for proton dissociation. The results are compared to other measurements. The W γp and t-dependences are parametrised using phenomenological fits. (orig.)
International Nuclear Information System (INIS)
Rolfe, R.M.
1976-12-01
The goal of the research was to investigate proton scattering on nuclei at intermediate energies and in particular to investigate proton scattering on helium. A theoretical investigation of the helium nucleus and the nature of the intermediate energy interaction, design and optimization of an energy-loss spectrometer facility for proton-nucleus scattering, and the unique superfluid helium target and experimental design are discussed
International Nuclear Information System (INIS)
Armour, E.A.G.; Beker, C.A.; Farina, J.E.G.
1981-01-01
P-wave phaseshifts for positron-hydrogen elastic scattering are calculated using a new adiabatic approximation in which the length of the radius vector from the proton to the positron is fixed but its direction is allowed to vary. This adiabatic approximation makes possible the full inclusion in the calculation of virtual states in which angular momentum is transferred to the target H atom. The results obtained agree qualitatively with the highly accurate results of Bhatia and co-workers (Phys. Rev.; A9:219 (1974)) and are much closer to them than the results obtained using the usual adiabatic approximation in which the radius vector from the proton to the positron is fixed. (author)
Quasi-elastic neutron scattering study of a re-entrant side-chain liquid-crystal polyacrylate
Benguigui, L.; Noirez, L.; Kahn, R.; Keller, P.; Lambert, M.; Cohen de Lara, E.
1991-04-01
We present a first investigation of the dynamics of a side chain liquid crystal polyacrylate in the isotropic (I), nematic (N), smectic A (SA), and re-entrant nematic (NRe) phases by means of quasi-elastic neutron scattering. The motion or/and the mobility of the mesogen protons decreases as soon as the temperature decreases after the isotropic-nematic transition. The I-N and SA-NRe transitions corrspond to a jump in the curve of the Elastic Incoherent Structure Factor (ratio: elastic scattering/ total scattering) versus temperature, on the other hand the transition N-SA occurs without any change of slope. We conclude that the local order is very similar in the nematic and the smectic A phases. Nous présentons une première étude dynamique par diffusion quasi-élastique des neutrons, d'un échantillon de polyacrylate mésomorphe en peigne dans chacune des phases : isotrope, nématique, smectique et nématique rentrante. On montre que le mouvement et/ou la mobilité des protons du mésogène se restreint à mesure que la température diminue après la transition isotrope-nématique. Contrairement à la transition N-SA, les transitions I-N et SA-NRe correspondent à une discontinuité dans la courbe du Facteur de Structure Incohérent Elastique (rapport : intensité élastique/intensité totale) en fonction de la température ; l'ordre local semble donc très proche pour les phases nématique et smectique.
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
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.
P-barp and pp elastic scattering from 10 GeV to 1000 GeV centre-of-mass energy
International Nuclear Information System (INIS)
Islam, M.M.; Fearnley, T.; Guillaud, J.P.
1984-01-01
Antiproton-proton and proton-proton elastic scattering are studied simultaneously over the energy range √s approx. (10-1000) GeV in a nucleon valence core model proposed earlier. The scattering is described as primarily due to two processes: diffraction and hard scattering. The latter originates from the scattering of a nucleon core off another core. Destructive interference between the two processes produces dips in p-barp and pp differential cross-sections. As energy increases beyond the ISR range (√s = (23-62) GeV), the dips get filled up, and eventually transform into shoulders or breaks at collider energies. Differences between p-barp and pp differential cross-sections persist even at collider energies. Comparison with ISR data shows that the model provides a quantitative description of pp elastic scattering in this energy range. Predictions of p-barp and pp differential cross-sections at future collider energies √s = 800 and 2000 GeV are given. In order to distinguish between competing models, need for measuring the p-barp differential cross-section at the ISR and SPS collider in the abs (t)-range (0.5-2.0) (GeV) 2 is stressed