Electron scattering from nucleons and deuterons at intermediate energies
International Nuclear Information System (INIS)
Burkert, V.
1985-04-01
Recent results from electron scattering of nucleons and deuterons are discussed. A tentative physics program for ELSA employing the polarized electron beams as well as the polarized nucleon and deuteron target facilities is outlined. (orig.)
Scattering of high energy electrons on deuteron
International Nuclear Information System (INIS)
Grossetete, B.
1964-12-01
The aim of this work is to obtain information on the neutron form factor from the study of the scattering of electrons on deuterium. The first part is dedicated to the theoretical study of the elastic and inelastic scattering. We introduce different form factors: Sachs form factor, the Pauli and Dirac form factors, they appear in the analytic expression of the scattering cross-section. We show how the deuteron form factors can be deduced from neutron's and proton's form factors. In the case of the inelastic scattering we show how the cross section can be broken into components associated to partial waves and we obtain different formulas for the inelastic cross-section based on the Breit formula or the Durand formalism. The second part is dedicated to the experiment setting of electron scattering on deuterium. The elastic scattering experiment has been made on solid or liquid CD 2 targets while inelastic scattering has been studied on a liquid target. We have used an electron beam produced by the Orsay linear accelerator and the scattered electrons have been analysed by a magnetic spectrometer and a Cerenkov detector. The results give a very low value (slightly positive)for the charge form factor of the neutron and a magnetic form factor for the neutron slightly below that of the proton [fr
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
THEORY OF ELECTRON-DEUTERON SCATTERING
Energy Technology Data Exchange (ETDEWEB)
Durand, L. III
1963-06-15
Information on the electromagnetic form factors of the neutron is obtained from the theory of inelastic electrondeuteron scattering. Problems in the analysis of these experiments that are related to the detailed structure of the deuteron and to the strong final state interactions between the emergent nucleons are considered. Problems arising from an ambiguity in the sign of the Dirac or charge form factor are also discussed. (C.E.S.)
Hadronic parity violation and inelastic electron-deuteron scattering
International Nuclear Information System (INIS)
Liu, C.-P.; Prezeau, G.; Ramsey-Musolf, M.J.
2003-01-01
We compute contributions to the parity-violating (PV) inelastic electron-deuteron scattering asymmetry arising from hadronic PV. While hadronic PV effects can be relatively important in PV threshold electrodisintegration, we find that they are highly suppressed at quasielastic kinematics. The interpretation of the PV quasielastic asymmetry is, thus, largely unaffected by hadronic PV
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
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
Electron-deuteron scattering in a relativistic theory of hadrons
International Nuclear Information System (INIS)
Phillips, D.
1998-11-01
The author reviews a three-dimensional formalism that provides a systematic way to include relativistic effects including relativistic kinematics, the effects of negative-energy states, and the boosts of the two-body system in calculations of two-body bound-states. He then explains how to construct a conserved current within this relativistic three-dimensional approach. This general theoretical framework is specifically applied to electron-deuteron scattering both in impulse approximation and when the ρπγ meson-exchange current is included. The experimentally-measured quantities A, B, and T 20 are calculated over the kinematic range that is probed in Jefferson Lab experiments. The role of both negative-energy states and meson retardation appears to be small in the region of interest
International Nuclear Information System (INIS)
David Abbott; Abdellah Ahmidouch; Heinz Anklin; Francois Arvieux; Jacques Ball; Beedoe, S.; Elizabeth Beise; Louis Bimbot; Werner Boeglin; Herbert Breuer; Roger Carlini; Nicholas Chant; Samuel Danagoulian; Dow, K.; Jean-Eric Ducret; James Dunne; Lars Ewell; Laurent Eyraud; Christophe Furget; Michel Garcon; Ronald Gilman; Charles Glashausser; Paul Gueye; Kenneth Gustafsson; Kawtar Hafidi; Adrian Honegger; Juerg Jourdan; Serge Kox; Gerfried Kumbartzki; Lu, L.; Allison Lung; David Mack; Pete Markowitz; Justin McIntyre; David Meekins; Fernand Merchez; Joseph Mitchell; Mohring, R.; Sekazi Mtingwa; Hamlet Mkrtchyan; David Pitz; Liming Qin; Ronald Ransome; Jean-Sebastien Real; Philip Roos; Paul Rutt; Reyad Sawafta; Samuel Stepanyan; Raphael Tieulent; Egle Tomasi-Gustafsson; William Turchinetz; Kelley Vansyoc; Jochen Volmer; Eric Voutier; William Vulcan; Claude Williamson; Stephen Wood; Chen Yan; Jie Zhao; Wenxia Zhao
2000-01-01
Tensor polarization observables (t20, t21 and t22) have been measured in elastic electron-deuteron scattering for six values of momentum transfer between 0.66 and 1.7 (GeV/c) 2 . The experiment was performed at the Jefferson Laboratory in Hall C using the electron HMS Spectrometer, a specially designed deuteron magnetic channel and the recoil deuteron polarimeter POLDER. The new data determine to much larger Q 2 the deuteron charge form factors G C and G Q . They are in good agreement with relativistic calculations and disagree with pQCD predictions
Measurement of Deuteron Tensor Polarization in Elastic Electron Scattering
Energy Technology Data Exchange (ETDEWEB)
Gustafsson, Kenneth K. [Univ. of Maryland, College Park, MD (United States)
2000-01-01
Nuclear physics traces it roots back to the very beginning of the last century. The concept of the nuclear atom was introduced by Rutherford around 1910. The discovery of the neutron Chadwick in 1932 gave us the concept of two nucleons: the proton and the neutron. The Jlab electron accelerator with its intermediate energy high current continuous wave beam combined with the Hall C high resolution electron spectrometer and a deutron recoil polarimeter provided experiment E94018 with the opportunity to study the deuteron electomagnetic structure, in particular to measure the tensor polarization observable t_{20}, at high four momentum transfers than ever before. This dissertation presents results of JLab experiment E94018.
International Nuclear Information System (INIS)
Simon, G.G.
1978-01-01
In this thesis results of measurements of the differential cross sections of the elastic and inelastic electron deuteron scattering are presented. The data were taken at several scattering angles and in the electron energy range of 150 MeV up to 320 MeV. The extracted form factors and structure functions are compared with theoretical results which are sensitive to details of nucleon structure and of the nucleon-nucleon forces. (FKS)
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.
Electron scattering from the deuteron using the Gross equation
Energy Technology Data Exchange (ETDEWEB)
J.W. Van Orden; N. Devine; F. Gross
1996-01-01
The elastic electromagnetic form factors for the deuteron are calculated in the context of a one-boson-exchange model using the Gross or Spectator equation [1]. The formalism is manifestly covariant and gauge invariant. Results are shown for the impulse approximation and for pxy exchange currents. The impulse approximation results are quite close to the available data which suggests that only a relatively small exchange current contribution is required. It is shown that by using a soft form factor for the exchange current, the model provides a very good representation of the data.
The SAMPLE experiment: Parity-violating electron scattering from the proton and deuteron
International Nuclear Information System (INIS)
Pitt, M.; Arrington, J.; Beck, D.; Beise, E.; Candell, E.; Cardman, L.; Carr, R.; Dodson, G.; Dow, K.; Duncan, F.; Farkhondeh, M.; Filippone, B.; Forest, T.; Gao, H.; Korsch, W.; Kowalski, S.; Lung, A.; McKeown, R.; Mohring, R.; Mueller, B.; Napolitano, J.; Simicevic, N.; Terburg, B.; Witkowski, M.
1995-01-01
Recent experimental evidence on nucleon structure has provided indications that some strange quark matrix elements can be comparable to those involving up and down quarks. The SAMPLE experiment will determine the strange magnetic form factor G s M at Q 2 =0.1 (GeV/c) 2 from a measurement of the asymmetry in the scattering of polarized electrons from the proton. The error on the extraction of G s M is ultimately limited by a theoretical uncertainty---the uncertain electroweak hadronic radiative correction to the axial form factor, R T=1 A . To address this issue, the collaboration is also approved to measure the asymmetry in parity-violating quasielastic electron scattering from the deuteron. The combination of the proton and deuteron measurements will yield a value of G s M that is almost completely free of the uncertainty in R T=1 A
Study of deep inelastic scattering of polarized electrons off polarized deuterons
International Nuclear Information System (INIS)
Kuriki, M.
1996-03-01
This thesis describes a 29GeV electron - nucleon scattering experiment carried out at Stanford Linear Accelerator Center (SLAC). Highly polarized electrons are scattered off a polarized ND 3 target. Scattered electrons are detected by two spectrometers located in End Station A (ESA) at angles of 4.5 degrees and 7 degrees with respect to the beam axis. We have measured the spin structure function g 1 of deuteron over the range of 0.029 2 2 . This integral indicates a discrepancy of more than three standard deviations from the prediction of the Ellis-Jaffe sum rule, 0.068±0.005 at Q 2 = 3.0(GeV/c) 2 while our result of g 1 d in good agreement with SMC results. Combined with g 1 of the proton, the measurement of ∫ 0 1 (g 1 d -g 1 n ) is 0.169±0.008. We also obtained the strong coupling constant at Q 2 = 3.0(GeV/c) 2 to be 0.417 -0.110 +0.086 , using the power correction for the sum rule up to third order of α s . This result is in agreement with the strong coupling constant α s (Q 2 ) = 3.0(GeV/c 2 ) obtained from various experiments. Using our deuteron results and the axial vector couplings of hyperon decays, the total quark polarization along the nucleon spin is found to be 0.286±.055, implying that quarks carry only 30% of the nucleon spin. The strange sea quark polarization is also determined to be -0.101 ± .023. These measurements are in agreement with other experiments and provide the world's most precise measurement of these quark polarizations. 80 refs., 151 figs., 23 tabs
Exclusive scattering off the deuteron
Energy Technology Data Exchange (ETDEWEB)
Amrath, D.
2007-12-15
Exclusive processes are a special class of processes giving insight into the inner structure of hadrons. In this thesis we consider two exclusive processes and compute their total cross sections as well as the beam charge and beam polarization asymmetries for different kinematical constraints. These calculations o er the opportunity to get access to the nonperturbative GPDs. Theoretically they can be described with the help of models. The rst process we investigate contains a GPD of the pion, which is basically unknown so far. We include different models and make predictions for observables that could in principle be measured at HERMES at DESY and CLAS at JLab. The second process we consider is electron-deuteron scattering in the kinematical range where the deuteron breaks up into a proton and a neutron. This can be used to investigate the neutron, which cannot be taken as a target due to its lifetime of approximately 15 minutes. For the calculation of the electron-deuteron cross section we implement models for the proton and neutron GPDs. Once there are experimental data available our calculations are ready for comparison. (orig.)
Parity-Violating Electron Deuteron Scattering and the Proton's Neutral Axial Vector Form Factor
International Nuclear Information System (INIS)
Ito, T.
2003-01-01
The authors report on a new measurement of the parity-violating asymmetry in quasielastic electron scattering from the deuteron at the backward angles at electron beam energy of 125 MeV [Q 2 =0.038 (GeV/c) 2 ]. This quantity provides a determination of the neutral weak axial vector form factor of the nucleon. In addition to the tree level amplitude associated with Z-exchange, the neutral weak axial vector form factor as measured in electron scattering can potentially receive large electroweak corrections, including the anapole moment, that are absent in neutrino scattering. The measured asymmetry A -3.51 ± 0.57 (stat) ± 0.58 (sys) ppm is consistent with theoretical predictions. We also report on updated results of the previous experiment at 200 MeV [Q 2 = 0.091 (GeV/c) 2 ] on a deuterium target. The updated results are also consistent with theoretical predictions on the neutral weal axial vector form factor
International Nuclear Information System (INIS)
Gakh, G.I.; Tomasi-Gustafsson, E.
2006-01-01
The general spin structure of the matrix element, taking into account the 2-photon exchange contribution, for the elastic electron (positron) - deuteron scattering has been derived using general symmetry properties of the hadron electromagnetic interaction, such as P-, C- and T-invariances as well as lepton helicity conservation in QED at high energy. Taking into account also crossing symmetry, the amplitudes of e ± d scattering can be parametrized in terms of fifteen real functions. The expressions for the differential cross section and for all polarization observables are given in terms of these functions. We consider the case of an arbitrary polarized deuteron target and polarized electron beam (both longitudinal and transverse). The transverse polarization of the electron beam induces a single-spin asymmetry which is non-zero in presence of 2-photon exchange. It is shown that elastic deuteron electromagnetic form factors can still be extracted in presence of 2 photon exchange, from the measurements of the differential cross sections and of one polarization observable (for example, the tensor asymmetry) for electron and positron deuteron elastic scattering, in the same kinematical conditions. (authors)
Strikman, M.; Weiss, C.
2018-03-01
We consider electron-deuteron deep-inelastic scattering (DIS) with detection of a proton in the nuclear fragmentation region ("spectator tagging") as a method for extracting the free neutron structure functions and studying their nuclear modifications. Such measurements could be performed at a future electron-ion collider (EIC) with suitable forward detectors. The measured proton recoil momentum (≲100 MeV in the deuteron rest frame) specifies the deuteron configuration during the high-energy process and permits a controlled theoretical treatment of nuclear effects. Nuclear and nucleonic structure are separated using methods of light-front quantum mechanics. The impulse approximation to the tagged DIS cross section contains the free neutron pole, which can be reached by on-shell extrapolation in the recoil momentum. Final-state interactions (FSIs) distort the recoil momentum distribution away from the pole. In the intermediate-x region 0.1 rest frame momenta ≲1 GeV , target fragmentation region). We construct a schematic model describing this effect, using final-state hadron distributions measured in nucleon DIS experiments and low-energy hadron scattering amplitudes. We investigate the magnitude of FSIs, their dependence on the recoil momentum (angular dependence, forward/backward regions), their analytic properties, and their effect on the on-shell extrapolation. We comment on the prospects for neutron structure extraction in tagged DIS with an EIC. We discuss possible extensions of the FSI model to other kinematic regions (large/small x ). In tagged DIS at x ≪0.1 FSIs resulting from diffractive scattering on the nucleons become important and require separate treatment.
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
Electron Scattering on deuterium
International Nuclear Information System (INIS)
Platchkov, S.
1987-01-01
Selected electron scattering experiments on the deuteron system are discussed. The main advantages of the electromagnetic probe are recalled. The deuteron A(q 2 ) structure function is analyzed and found to be very sensitive to the neutron electric form factor. Electrodisintegration of the deuteron near threshold is presented as evidence for the importance of meson exchange currents in nuclei [fr
International Nuclear Information System (INIS)
Hummel, E.; Tjon, J.A.
1989-01-01
Using the one-boson-exchange model a relativistic covariant analysis is carried out of the elastic electromagnetic form factors of the deuteron including the ρπγ and ωεγ mesonic-exchange-current contributions. The theoretical predictions are compared with the recent experimental data at high momentum transfer
Intermediate energy nucleon-deuteron scattering theory.
Wilson, J. W.
1973-01-01
Sloan's conclusion (1969) that terms of the multiple-scattering series beyond single scattering contribute only to S- and P-wave amplitudes in an S-wave separable model is examined. A comparison of experiments with the calculation at 146 MeV shows that the conclusion is valid in nucleon-deuteron scattering applications.
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
Electron-deuteron scattering in the equal-time formalism: beyond the impulse approximation
Energy Technology Data Exchange (ETDEWEB)
D.R. Phillips; Stephen Wallace; N.K. Devine
2004-11-01
Using a three-dimensional formalism that includes relativistic kinematics, the effects of negative-energy states, approximate boosts of the two-body system, and current conservation, we calculate the electromagnetic form factors of the deuteron up to Q{sup 2} of 4 GeV{sup 2}. This is done using a dynamical boost for two-body systems with spin. We first compute form factors in impulse approximation, but then also add an isoscalar meson-exchange current of pion range that involves the gamma-pi contact operator associated with pseudovector pi-N coupling. We also consider effects of the rho-pi-gamma meson-exchange current. The experimentally measured quantities A, B, and t20 are calculated over the kinematic range probed in recent Jefferson Laboratory experiments. The rho-pi-gamma meson-exchange current provides significant strength in A at large Q{sup 2} and the gamma-pi contact-term exchange current shifts t20, providing good agreement with the JLab data. Relativistic effects and the gamma-pi meson-exchange current do not provide an explanation of the B observable, but the rho-pi-gamma current could help to provide agreement if a nonstandard value is used for the tensor rho-N coupling that enters this contribution.
Deuteron Compton scattering below pion photoproduction threshold
Levchuk, M. I.; L'vov, A. I.
2000-07-01
Deuteron Compton scattering below pion photoproduction threshold is considered in the framework of the nonrelativistic diagrammatic approach with the Bonn OBE potential. A complete gauge-invariant set of diagrams is taken into account which includes resonance diagrams without and with NN-rescattering and diagrams with one- and two-body seagulls. The seagull operators are analyzed in detail, and their relations with free- and bound-nucleon polarizabilities are discussed. It is found that both dipole and higher-order polarizabilities of the nucleon are required for a quantitative description of recent experimental data. An estimate of the isospin-averaged dipole electromagnetic polarizabilities of the nucleon and the polarizabilities of the neutron is obtained from the data.
Deuteron Compton scattering below pion photoproduction threshold
International Nuclear Information System (INIS)
Levchuk, M.I.; L'vov, A.I.
2000-01-01
Deuteron Compton scattering below pion photoproduction threshold is considered in the framework of the nonrelativistic diagrammatic approach with the Bonn OBE potential. A complete gauge-invariant set of diagrams is taken into account which includes resonance diagrams without and with NN-rescattering and diagrams with one- and two-body seagulls. The seagull operators are analyzed in detail, and their relations with free- and bound-nucleon polarizabilities are discussed. It is found that both dipole and higher-order polarizabilities of the nucleon are required for a quantitative description of recent experimental data. An estimate of the isospin-averaged dipole electromagnetic polarizabilities of the nucleon and the polarizabilities of the neutron is obtained from the data
Deuteron Compton scattering below pion photoproduction threshold
Energy Technology Data Exchange (ETDEWEB)
Levchuk, M.I. E-mail: levchuk@dragon.bas-net.by; L' vov, A.I. E-mail: lvov@x4u.lebedev.ru
2000-07-17
Deuteron Compton scattering below pion photoproduction threshold is considered in the framework of the nonrelativistic diagrammatic approach with the Bonn OBE potential. A complete gauge-invariant set of diagrams is taken into account which includes resonance diagrams without and with NN-rescattering and diagrams with one- and two-body seagulls. The seagull operators are analyzed in detail, and their relations with free- and bound-nucleon polarizabilities are discussed. It is found that both dipole and higher-order polarizabilities of the nucleon are required for a quantitative description of recent experimental data. An estimate of the isospin-averaged dipole electromagnetic polarizabilities of the nucleon and the polarizabilities of the neutron is obtained from the data.
Shadowing in inelastic lepton-deuteron scattering
International Nuclear Information System (INIS)
Badelek, B.
1992-01-01
Shadowing in inelastic lepton-deuteron scattering is analysed using the double interaction formalism where we relate shadowing to inclusive diffractive processes. Both the vector meson and parton contributions are considered for low and high Q 2 values including QCD corrections with parton recombination for high Q 2 . These Q 2 values were chosen to correspond to existing experimental data and to the possible HERA measurements. Detailed discussion of various shadowing mechanisms is given. As expected the shadowing effects are found to be very small, less then 2% or so, in agreement with the recent precise measurements performed by the New Muon Collaboration. The contribution of shadowing term to the Gottfried sum the region x > 0.004 and for Q 2 = 4 GeV 2 is estimated to be equal to -0.025. (author). 10 refs, 4 figs
International Nuclear Information System (INIS)
Mantry, Sonny; Ramsey-Musolf, Michael J.; Sacco, Gian Franco
2010-01-01
We show that parity-violating deep-inelastic scattering (PVDIS) of longitudinally polarized electrons from deuterium can in principle be a relatively clean probe of higher twist quark-quark correlations beyond the parton model. As first observed by Bjorken and Wolfenstein, the dominant contribution to the electron polarization asymmetry, proportional to the axial vector electron coupling, receives corrections at twist four from the matrix element of a single four-quark operator. We reformulate the Bjorken-Wolfenstein argument in a matter suitable for the interpretation of experiments planned at the Thomas Jefferson National Accelerator Facility (JLab). In particular, we observe that because the contribution of the relevant twist-four operator satisfies the Callan-Gross relation, the ratio of parity-violating longitudinal and transverse cross sections, R γZ , is identical to that for purely electromagnetic scattering, R γ , up to perturbative and power-suppressed contributions. This result simplifies the interpretation of the asymmetry in terms of other possible novel hadronic and electroweak contributions. We use the results of MIT Bag Model calculations to estimate contributions of the relevant twist-four operator to the leading term in the asymmetry as a function of Bjorken x and Q 2 . We compare these estimates with possible leading twist corrections from violation of charge symmetry in the parton distribution functions.
International Nuclear Information System (INIS)
Schneider, H.
1978-06-01
The mechanism of the quasifree scattering (QFS) in the reaction dd → dpn has been investigated systematically by means of kinematically complete coincidence experiments using 52 MeV deuterons. In order to measure the angular distributions of the quasifree dp scattering and the quasifree dn scattering, the kinematical conditions were chosen to favour quasifree scattering of deuterons on bound nucleons of the target deuteron. (orig.) [de
Study of double scattering effect in antiproton--deuteron annihilation
International Nuclear Information System (INIS)
Zemany, P.D.
1975-01-01
The double scattering process in the deuteron is investigated for the reaction anti pd → p/sub s/ + mesons. About 30 percent of the apparent anti pn annihilations are involved in double scattering. A model which describes the properties of protons emerging from apparent anti pn annihilations is presented
Hadron--deuteron scattering at 50 GeV
International Nuclear Information System (INIS)
Levinson, L.J.
1978-06-01
The forward scattering of π + , π - , and protons on deuterons and protons was measured with a single arm spectrometer at the Fermi National Accelerator Laboratory. The energy was 50 GeV and the invariant 4-momentum transfer range was .06 2 for π + and p, and .06 - . The missing mass, determined by the spectrometer, selected proton elastic and deuteron elastic-plus-breakup scattering, rejecting particle and resonance production events. The measured proton and deuteron differential cross sections were analyzed in the context of the Glauber Theory of deuteron elastic-plus-breakup scattering and a neutron elastic differential cross section was extracted. The theory and analysis were tested by comparing the π + n cross section extracted from the π + d and n + p data with the π - p data; by I-spin symmetry the π + n cross section must equal the π - p. The same test was done for π - n. The proton--neutron elastic differential cross section was then extracted from the pd and pp data. The theory and the data were not found to be consistent within the random errors. Systematic errors are probably the cause; several possible systematic errors are discussed. Also an attempt to use recoil particle detectors to extract the deuteron elastic and the neutron cross sections is reported
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
Pion deuteron scattering at intermediate energies
International Nuclear Information System (INIS)
Ferreira, E.M.
1978-09-01
A comparison is made of results of calculations of πd elastic scattering cross section using multiple scattering and three-body equations, in relation to their ability to reproduce the experimental data at intermediate energies. It is shown that the two methods of theoretical calculation give quite similar curves for the elastic differential cross sections, and that both fail in reproducing backward scattering data above 200MeV. The new accurate experimental data on πd total cross section as a function of the energy are confronted with the theoretical values obtained from the multiple scattering calculation through the optical theorem. Comparison is made between the values of the real part of the forward amplitude evaluated using dispersion relations and using the multiple scattering method [pt
The Hilbert-Schmidt method for nucleon-deuteron scattering
International Nuclear Information System (INIS)
Moeller, K.; Narodetskii, I.M.
1984-01-01
The Hilbert-Schmidt technique is used for computing the divergent multiple-scattering series for scattering of nucleons by deuterons at energies above the deuteron breakup. We have found that for each partial amplitude a series of s-channel resonances diverges because of the logarithmic singularities which reflect the t-channel singularities of the total amplitude. However, the convergence of the Hilbert-Schmidt series may be improved by iterating the Faddeev equations thereby extracting the most strong logarithmic singularities. We show that the series for the amplitudes with the first two iteration subtracted converges rapidly. Our final results are in excellent agreement with exact results obtained by a direct matrix technique. (orig.)
Hilbert-Schmidt method for nucleon-deuteron scattering
International Nuclear Information System (INIS)
Moeller, K.; Narodetskij, I.M.
1983-01-01
The Hilbert-Schmidt technique is used for computing the divergent multiple-scattering series for scattering of nucleons by deuterons at energies above the deuteron breakup. It is found that for each partial amplitude a series of s-channel resonances diverges because of the logarithmic singularities which reflect the t-channel singularities of the total amplitude. However, the convergence of the Hilbert-Schmidt series may be improved by iterating the Faddeev equations thereby extracting the most strong logarithmic singularities. It is shown that the series for the amplitudes with first two iterations subtracted converges rapidly. Final results are in excellent agreement with exact results obtained by a direct matrix technique
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.)
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.)
On deformed tensor potential for inelastic deuteron scattering
International Nuclear Information System (INIS)
Raynal, Jacques.
1980-08-01
Tensor analysing powers for inelastic deuteron scattering have been measured around 12 to 15 MeV. There is no problem to use such a tensor potential for the excited states in coupled channel calculations. However, for transition potentials, form factors are very different. A fit has been done with the first order vibrational model for 64 Ni(d,d') 64 Ni*, 2 + at 1,344 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
International Nuclear Information System (INIS)
Holt, R.J.
1992-01-01
Two of the simplest nuclear reactions, electron deuteron elastic scattering and deuteron photodisintegration, will be discussed. In particular, measurements of the tensor analyzing power T 20 in e-d scattering performed with a polarized gas target in the VEPP-3 electron storage ring will be presented. In addition, measurements of deuteron photodisintegration at high energy performed at SLAC will be discussed. The meson-exchange calculations appear to agree well with al available data for electron-deuteron elastic scattering, while the constituent counting rules appear to describe the high-energy deuteron photodisintegration results at θcm = 90 degrees
International Nuclear Information System (INIS)
Bondarenko, S.G.; Burov, V.V.; Hamamoto, N.; Manabe, Y.; Hosaka, A.; Toki, H.
2005-01-01
Recent results obtained by the application of the Bethe-Salpeter approach to the analysis of elastic electron-deuteron scattering with the separable NN kernel are presented. We analyze the impact of the P waves (negative-energy components) on the electromagnetic properties of the deuteron and compare it with experimental data. It was shown that the contribution of the P waves must be taken into account to explain tensor polarization and charge form factor of the deuteron
Polarization of recoil deuteron in ed elastic scattering at medium energies
International Nuclear Information System (INIS)
Bhalerao, R. S.
1981-12-01
Vector and tensor polarizations of the recoil deuteron in ed elastic scattering are calculated for THETA=0deg-180deg and q 2 2 . A longitudinally polarized electron beam is assumed to scatter off an unpolarized deuteron target. Calculations are made in the relativistic impulse approximation using a recently described approach based on the Bethe-Salpeter equation. Results are different, at high q 2 even qualitatively so, from those of a non-relativistic calculation, and a relativistic calculation which takes the spectator nucleon on-mass-shell. In the light of these results a recent suggestion that the polarization measurements would throw new light on the off-shell behavior and tensor force strength of the NN interaction are reexamined. Results are also presented for the three deuteron form factors Gsub(C), Gsub(Q), and Gsub(M), and the often-needed related quantities Ssub(S), Ssub(Q), and Ssub(M). The latter results may have an important implication in high-momentum transfer reactions involving deuteron. (author)
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)
Local and non-local potentials for deuteron elastic scattering
International Nuclear Information System (INIS)
Ramirez, J.A.
1976-01-01
The nucleon--nucleus local potential (central and spin--orbit) and the deuteron--nucleus nonlocal potential (central, spin--orbit, spin--radial tensor) are calculated by the folding-model (FM). Simple analytic expressions are obtained for the nucleon--nucleus potential by the use of Gaussians to represent the nucleon--nucleus potential and the charge and mass densities of the target. The analytic expressions give qualitative descriptions of phenomenological nucleon--nucleus interactions. A systematic target--mass dependence of realistic local FM deueron potentials is also included. Local-equivalent, energy-dependent, deuteron potentials are obtained from the nonlocal FM deuteron potentials and the energy dependence of the local potential parameters are presented. The local FM deuteron potential is tested for 60 Ni(d,d) 60 Ni at E/sub α/ = 15 MeV by comparing the predictions of the FM potentials with data in which all five polarization moments were measured. A qualitative fit to the data is obtained, but it overestimates the volume integral of the central potential by 7%. Energy-dependence effects are estimated by evaluating the local-equivalent potentials at E/sub α/ = 30 MeV and comparing the predictions to the E/sub α/ = 15 MeV potentials. The energy dependence of the central potential dominates the angular dependence of all five observables while the energy dependence of the spin--orbit and tensor potentials produces only scale changes (approx. 3%) in the vector and tensor analyzing powers. The scattering formalism for a spin-1 on a spin-0 target nucleus, and a description of the coupled--channels computer code DDUNC1 which treats the spin--radial tensor potential exactly, are included
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
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
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
QED corrections in deep-inelastic scattering from tensor polarized deuteron target
Gakh, G I
2001-01-01
The QED correction in the deep inelastic scattering from the polarized tensor of the deuteron target is considered. The calculations are based on the covariant parametrization of the deuteron quadrupole polarization tensor. The Drell-Yan representations in the electrodynamics are used for describing the radiation real and virtual particles
Compton Scattering from the Deuteron at Low Energies
Energy Technology Data Exchange (ETDEWEB)
Lundin, Magnus [Lund Univ. (Sweden). Dept. of Physics
2002-05-01
A series of three Compton scattering experiments on deuterium have been performed at the high-resolution tagged-photon facility MAX-lab located in Lund, Sweden. The 50 < E{sub g} < 70 MeV tagged photons were scattered from a liquid deuterium target and detected simultaneously in three (10{sup x}10{sup )} NaI detectors. The average laboratory angles investigated were 45, 125 and 135 deg. The influence of the inelastic contribution was minimized by implementing a narrow elastic fit-region in the missing energy spectra. Absolute cross sections were extracted for average photon energies of 55 and 66 MeV at each angle and for each experiment. The extracted cross sections are in good agreement with those measured at Illinois by Lucas et al. The difference between the electric and magnetic isospin-averaged polarizabilities of the nucleon inside the deuteron, was varied within the calculations of Levchuk and L'vov to best reproduce the data, holding the sum fixed at 14.6 (10{sup -4} fm{sup 3}). The result implies that the electric polarizability of the neutron is the same as that of the proton within the experimental uncertainties. The result also indicates that the magnetic polarizability of the neutron is larger than that of the proton.
Coupled channel theory of pion--deuteron reaction applied to threshold scattering
International Nuclear Information System (INIS)
Mizutani, T.; Koltun, D.S.
1977-01-01
Scattering and absorption of pions by a nuclear target are treated together in a coupled channel theory. The theory is developed explicitly for the problem of pion scattering and absorption by a deuteron. The equations are presented in terms of the integral equations of three-body scattering theory. The method is then applied in an approximate from to calculate the contribution of pion absorption to the scattering length for pion--deuteron scattering. The sensitivity of the calculated results to the model assumptions and approximations is investigated
International Nuclear Information System (INIS)
Arnold, R.G.; Chertok, B.T.; Dally, E.B.; Grigorian, A.; Jordan, C.L.; Schuetz, W.P.; Zdarko, R.; Martin, F.; Mecking, B.A.
1975-06-01
Preliminary results of elastic eD scattering at large momentum transfer performed at the Stanford Linear Accelerator Center using two high resolution spectrometers in coincidence are reported. The deuteron structure function A(q 2 ) is deduced at 9 values of q 2 from a comparison of elastic eD and eP coincident yields and the world's eP cross sections. These measurements extend the range of q 2 by 4.5 over previous work, and in this new range A(q 2 ) is observed to approach 1/q 20 momentum dependence. Results are in sharp disagreement with the meson exchange calculations, and they are in rough agreement with the nonrelativistic potential models, and they are in agreement with the predictions of the quark dimensional scaling model which pictures the deuteron as a bound state of 6 quarks at large momentum transfer
Compton Scattering from the Deuteron at Low Energies
International Nuclear Information System (INIS)
Lundin, Magnus
2002-05-01
A series of three Compton scattering experiments on deuterium have been performed at the high-resolution tagged-photon facility MAX-lab located in Lund, Sweden. The 50 g x 10 ) NaI detectors. The average laboratory angles investigated were 45, 125 and 135 deg. The influence of the inelastic contribution was minimized by implementing a narrow elastic fit-region in the missing energy spectra. Absolute cross sections were extracted for average photon energies of 55 and 66 MeV at each angle and for each experiment. The extracted cross sections are in good agreement with those measured at Illinois by Lucas et al. The difference between the electric and magnetic isospin-averaged polarizabilities of the nucleon inside the deuteron, was varied within the calculations of Levchuk and L'vov to best reproduce the data, holding the sum fixed at 14.6 (10 -4 fm 3 ). The result implies that the electric polarizability of the neutron is the same as that of the proton within the experimental uncertainties. The result also indicates that the magnetic polarizability of the neutron is larger than that of the proton
International Nuclear Information System (INIS)
Ballot, J.L.; L'Huillier, M.; Combes, M.P.; Tatischeff, B.
1984-01-01
An analysis of deuteron-deuteron scattering data at 3.0, 3.4 and 3.7 GeV/c is given in the framework of the Glauber NN multiple scattering model. The model accounts qualitatively well for the larger momentum transfer data. The model cannot reproduce the observed experimental bump at small transfer in the region of missing mass 2GeV/c, because pionic processes have been considered. Nevertheless it shows that the nucleon background is important
The Kemmer-Duffin-Petiau formalism and intermediate-energy deuteron-nucleus scattering
International Nuclear Information System (INIS)
Kozack, R.E.; Clark, B.C.; Hama, S.; Mishra, V.K.; Kaelbermann, G.; Mercer, R.L.; Ray, L.
1988-01-01
The spin-1 Kemmer-Duffin-Petiau (KDP) equations are described and applied to deuteron-nucleus scattering. Comparison with d + 58 Ni elastic scattering data at 400 MeV shows that the KDP model; reproduces experimental spin observables very well. 11 refs., 1 fig
Study of the baryon-baryon interaction in nucleon-nucleon and pion-deuteron scattering
International Nuclear Information System (INIS)
Fuchs, M.
1993-01-01
After the definition of the Hamiltonian in general form by meson production and absorption the transition to operators pursued, which connect only spaces with definite meson numbers. In this approximation first the self-energy of a single baryon was calculated in its full energy and momentum dependence. Then the formal expressions for the T matrices of nucleon-nucleon and pion-deuteron scattering were derived. The essential components of these expressions are the baryon-baryon T matrix ant transition amplitudes from pion-deuteron channels to baryon-baryon states. The central chapter dealt with the calculation of the baryon-baryon interaction for the general form of the vertices, with the solution of the binding problem and the baryon-baryon T matrix. Finally followed the results on the nucleon-nucleon and pion-deuteron scattering. For this first the transition amplitudes from pion-deuteron states to intermediate baryon-baryon states and the Born graphs of the pion-deuteron scattering had to be calculated. After some remarks to the transition from partial-wave decomposed T matrices to scattering observables an extensive representation of the total, partial, and differential cross sections and a series of spin observables (analyzing powers and spin correlations) for the elastic proton-proton, neutron-proton, and pion-deuteron scattering as well for the fusion reaction pp→πd and the breakup reaction πd→pp follows. Thereby the energies reached from the nucleon-nucleon respectively pion-deuteron threshold up to 100 MeV above the delta resonance
Deuteron-nucleus scattering at Ed = 34 and 80 MeV
International Nuclear Information System (INIS)
Rahman, M.A.; Kumar Sarker, S.; Sen Gupta, H.M.
1992-03-01
34 and 80 MeV deuterons scattered elastically from some nuclei between 12 C and 208 Pb are analysed using the 3-parameter strong absorption model due to Frahn and Venter. The interaction radius, surface diffuseness and the reaction cross section have been determined from the best fit values of T,Δ and μ. The inelastic scattering of deuterons from even-even nuclei 12 C, 58 Ni, 68 Zn and 120 Sn exciting to 2 + state are also analysed giving the deformation parameter. (author). 9 refs, 5 figs, 3 tabs
Hilbert-Schmidt expansion for the nucleon-deuteron scattering amplitude
International Nuclear Information System (INIS)
Moeller, K.; Narodetskii, I.M.
1983-01-01
The Hilbert-Schmidt method is used to sum the divergent iterative series for the partial amplitudes of nucleon-deuteron scattering in the energy region above the deuteron breakup threshold. It is observed that the Hilbert-Schmidt series for the partial amplitudes themselves diverges, which is due to the closeness of the logarithmic singularities. But if the first iterations in the series for multiple scattering are subtracted from the amplitude, the Hilbert-Schmidt series for the remainder converges rapidly. The final answer obtained in the present paper is in excellent agreement with the results obtained in exact calculations
On theory of π-mesons low-energy scattering on the deuterons
International Nuclear Information System (INIS)
Zubarev, A.L.; Irgaziev, B.F.; Podkopaev, A.P.; Fridman, A.A.
1979-01-01
The pion-deuteron scattering length is calculated using the equations derived by application of Shwinger variational principle to the strongly coupled channel method. The dependence upon the πN-scattering lengths, effective radii and shape of the NN potential is studied. The πN interaction is described by local potentials. The contribution given by closed channels to the πd-scattering length is shown to be of 30 %
Anomalous heat evolution of deuteron implanted Al on electron bombardment
International Nuclear Information System (INIS)
Kamada, K.; Kinoshita, H.; Takahashi, H.
1994-05-01
Anomalous heat evolution was observed in deuteron implanted Al foils on 175 keV electron bombardment. Local regions with linear dimension of several 100nm showed simultaneous transformation from single crystalline to polycrystalline structure instantaneously on the electron bombardment, indicating the temperature rise up to more than melting point of Al from room temperature. The amount of energy evolved was more than 180 MeV for each transformed region. The transformation was never observed in proton implanted Al foils. The heat evolution was considered due to a nuclear reaction in D 2 molecular collections. (author)
International Nuclear Information System (INIS)
Moss, J.M.
1985-01-01
An overview of intermediate energy (80 to 1000 MeV) study contributions to the International Polarization Symposium in Osaka, Japan, August 1985 is presented in this report. Contributions fall into three categories: polarization transfer, polarized deuteron scattering and polarized (p,π +- ) reactions
Doublet channel neutron-deuteron scattering in leading order effective field theory
B. BlankleiderFlinders U.; J. Gegelia(INFN)
2015-01-01
The doublet channel neutron-deuteron scattering amplitude is calculated in leading order effective field theory (EFT). It is shown that this amplitude does not depend on a constant contact interaction three-body force. Satisfactory agreement with available data is obtained when only two-body forces are included.
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.
Measurement of the longitudinal deuteron spin-structure function in deep-inelastic scattering
International Nuclear Information System (INIS)
Bauer, J.M.
1996-09-01
Experiment E143 at SLAC performed deep-inelastic scattering measurements with polarized electrons incident on polarized protons and deuterons. The data for the beam energy of 29 GeV cover the kinematical range of x Bj > 0.03 and 1 2 2 . From these data, the spin-dependent structure functions g 1 were determined. This dissertation describes the experiment and its analysis and discusses the results. The measured integral of g 1 d over x from x = 0 to x = 1 is Γ 1 d = 0.046 ± 0.003 (stat)±0.004 (syst) at Q 2 = 3 GeV 2 and disagrees by more than three standard deviations with the prediction of the Ellis-Jaffe, sum rule. The data suggest that the quark contribution to the nucleon helicity is 0.35 ± 0.05. From the proton data of the same experiment, the integral over the proton spin-structure functional g 1 d was determined to be Γ 1 p = 0.127 ± 0.003(stat)±0.008(syst). By Combining the deuteron data with the proton data, the integral Γ 1 n was extracted as -0.027 ± 0.008 (stat)±0.010 (syst). The integral Γ 1 p - Γ 1 n is 0.154±0.010(stat) ±0.016 (syst) according to the E143 analysis. This result agrees with the important Bjorken sum rule of 0.171 ± 0.009 at Q 2 = 3 GeV 2 within less than one standard deviation. Furthermore, results of a separate analysis involving GLAP evolution equations are shown. Data were also collected for beam energies of 16.2 and 9.7 GeV, Results for g 1 at these energies are presented
Nucleon polarizabilities from deuteron Compton scattering within a Green's function hybrid approach
Energy Technology Data Exchange (ETDEWEB)
Hildebrandt, R.P.; Hemmert, T.R. [Technische Universitaet Muenchen, Institut fuer Theoretische Physik (T39), Physik-Department, Garching (Germany); Griesshammer, H.W. [Technische Universitaet Muenchen, Institut fuer Theoretische Physik (T39), Physik-Department, Garching (Germany); Universitaet Erlangen-Nuernberg, Institut fuer Theoretische Physik III, Naturwissenschaftliche Fakultaet I, Erlangen (Germany); The George Washington University, Center for Nuclear Studies, Department of Physics, Washington DC (United States)
2010-10-15
We examine elastic Compton scattering from the deuteron for photon energies ranging from zero to 100MeV, using state-of-the-art deuteron wave functions and NN potentials. Nucleon-nucleon rescattering between emission and absorption of the two photons is treated by Green's functions in order to ensure gauge invariance and the correct Thomson limit. With this Green's function hybrid approach, we fulfill the low-energy theorem of deuteron Compton scattering and there is no significant dependence on the deuteron wave function used. Concerning the nucleon structure, we use the chiral effective field theory with explicit {delta} (1232) degrees of freedom within the small-scale expansion up to leading-one-loop order. Agreement with available data is good at all energies. Our 2-parameter fit to all elastic {gamma} d data leads to values for the static isoscalar dipole polarizabilities which are in excellent agreement with the isoscalar Baldin sum rule. Taking this value as additional input, we find {alpha}{sub E}{sup s} = (11.3{+-}0.7(stat){+-}0.6(Baldin){+-}1(theory)){sup .}10{sup -4} fm{sup 3} and {beta}{sub M}{sup s} = (3.2{+-}0.7(stat){+-}0.6(Baldin){+-}1(theory)){sup .}10{sup -4} fm{sup 3} and conclude by comparison to the proton numbers that neutron and proton polarizabilities are the same within rather small errors. (orig.)
Electron scattering from tetrahydrofuran
International Nuclear Information System (INIS)
Fuss, M C; Sanz, A G; García, G; Muñoz, A; Oller, J C; Blanco, F; Do, T P T; Brunger, M J; Almeida, D; Limão-Vieira, P
2012-01-01
Electron scattering from Tetrahydrofuran (C 4 H 8 O) was investigated over a wide range of energies. Following a mixed experimental and theoretical approach, total scattering, elastic scattering and ionization cross sections as well as electron energy loss distributions were obtained.
A study on basic theory for CDCC method for three-body model of deuteron scattering
International Nuclear Information System (INIS)
Kawai, Mitsuji
1988-01-01
Recent studies have revealed that the CDCC method is valid for treating the decomposition process involved in deuteron scattering on the basis of a three-body model. However, theoretical support has not been developed for this method. The present study is aimed at determining whether a solution by the CDCC method can be obtained 'correctly' from a 'realistic' model Hamiltonian for deuteron scattering. Some researchers have recently pointed out that there are some problems with the conventional CDCC calculation procedure in view of the general scattering theory. These problems are associated with asymptotic froms of the wave functions, convergence of calculations, and boundary conditions. Considerations show that the problem with asymptotic forms of the wave function is not a fatal defect, though some compromise is necessary. The problem with the convergence of calculations is not very serious either. Discussions are made of the handling of boundary conditions. Thus, the present study indicates that the CDCC method can be applied satisfactorily to actual deuteron scattering, and that the model wave function for the CDCC method is consistent with the model Hamiltonian. (Nogami, K.)
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
International Nuclear Information System (INIS)
Clement, H.; Frick, R.; Graw, G.; Schiemenz, P.; Seichert, N.
1983-01-01
The 2 1 + -excitation of deformed nuclei by tensor polarized deuterons provides an alignment of both nuclei and thus a means to study specifically the quadrupole-quadrupole interaction between both nuclei. The tensor analyzing power Asub(xz)(theta) has been measured for the elastic and inelastic scattering on 24 Mg and 28 Si. The coupled channel analysis including a deformed tensor potential reveals a clear signature of the quadrupole-quadrupole part of the nuclear projectile-target interaction. (orig.)
Elastic scattering of polarized deuterons from 40Ca and 58Ni at intermediate energies
International Nuclear Information System (INIS)
Sen, N. van; Arvieux, J.; Yanlin, Y.; Gaillard, G.; Bonin, B.; Boudard, A.; Bruge, G.; Lugol, J.C.; Babinet, R.; Hasegawa, T.; Soga, F.; Cameron, J.M.; Neilson, G.C.; Sheppard, D.M.
1985-01-01
Angular distributions of cross section, and Asub(y) and Asub(yy) analyzing powers were measured for polarized deuteron elastic scattering from 58 Ni at 200, 400 and 700 MeV, and 40 Ca at 700 MeV. Phenomenological potentials were obtained from an optical model analysis of the data. The total reaction cross sections deduced were compared to predictions from the Glauber theory optical limit. (orig.)
Calculations on nucleon-deuteron scattering with realistic potentials
International Nuclear Information System (INIS)
Stolk, C.
1978-01-01
The purpose of this study is to find out how the three-nucleon observables are affected by details of the two-nucleon force. The theory of the perturbational treatment of the Faddeev equations for the three-particle transition matrix, for both elastic and breakup scattering is dealt with. Some details of the numerical treatment are discussed, results for the elastic and breakup scattering presented and conclusions drawn. (C.F.)
International Nuclear Information System (INIS)
Raynal, J.
1963-01-01
The optical model has been applied with success to the elastic scattering of particles of spin 0 and 1/2 and to a lesser degree to that of deuterons. For particles of spin l/2, an LS coupling term is ordinarily used; this term is necessary to obtain a polarization; for deuterons, this coupling has been already introduced, but the possible forms of potentials are more numerous (in this case, scalar products of a second rank spin tensor with a tensor of the same rank in space or momentum can occur). These terms which may be necessary are primarily important for the tensor polarization. This problem is of particular interest at Saclay since a beam of polarized deuterons has become available. The FORTRAN program SPM 037 permits the study of the effect of tensorial potentials constructed from the distance of the deuteron from the target and its angular momentum with respect to it. This report should make possible the use and even the modification of the program. It consists of: a description of the problem and of the notation employed, a presentation of the methods adopted, an indication of the necessary data and how they should be introduced, and finally tables of symbols which are in equivalence or common statements: these tables must be considered when making any modification. (author) [fr
Nucleon-deuteron scattering with Δ-isobar excitation: Perturbation theory
International Nuclear Information System (INIS)
Deltuva, A.; Chmielewski, K.; Sauer, P.U.
2003-01-01
A perturbative approach for the description of elastic and inelastic nucleon-deuteron scattering is developed. Its validity is discussed. The aim of the perturbative approach is the isolation of details of different reaction mechanisms. The dynamics is based on a two-baryon potential allowing for the excitation of a nucleon to a Δ isobar. The coupled-channel potential yields an effective three-nucleon force in three-nucleon scattering. The purely nucleonic reference potential is the charge-dependent CD-Bonn potential
Electron scattering from pyrimidine
International Nuclear Information System (INIS)
Colmenares, Rafael; Fuss, Martina C; García, Gustavo; Oller, Juan C; Muñoz, Antonio; Blanco, Francisco; Almeida, Diogo; Limão-Vieira, Paulo
2014-01-01
Electron scattering from pyrimidine (C 4 H 4 N 2 ) was investigated over a wide range of energies. Following different experimental and theoretical approaches, total, elastic and ionization cross sections as well as electron energy loss distributions were obtained.
Secondary electron emission from 0.5--2.5-MeV protons and deuterons
International Nuclear Information System (INIS)
Thornton, T.A.; Anno, J.N.
1977-01-01
Measurement of the secondary electron currents leaving Al, V, Fe, 316 stainless steel, Nb, and Mo foils undergoing 0.5--2.5-MeV proton and deuteron bombardment were made to determine the secondary electron emission ratios for these ions. The measured secondary electron yields were of the order of 1.0, with the deuterons producing generally higher yields than the protons
Deuterium microscopy using 17 MeV deuteron–deuteron scattering
Energy Technology Data Exchange (ETDEWEB)
Reichart, Patrick, E-mail: patrick.reichart@unibw.de; Moser, Marcus; Greubel, Christoph; Peeper, Katrin; Dollinger, Günther, E-mail: guenther.dollinger@unibw.de
2016-03-15
Using 17 MeV deuterons as a micrometer focused primary beam, we performed deuterium microscopy by using the deuteron–deuteron (dd) scattering reaction. We describe our new box like detector setup consisting of four double sided silicon strip detectors (DSSSD) with 16 strips on each side, each covering up to 0.5 sr solid angle for coincidence detection. This method becomes a valuable tool for studies of hydrogen incorporation or dynamic processes using deuterium tagging. The background from natural hydrocarbon or water contamination is reduced by the factor 150 ppm of natural abundance of deuterium in hydrogen. Deuterium energies of up to 25 MeV, available at the microprobe SNAKE, are ideal for the analysis of thin freestanding samples so that the scattered particles are transmitted to the detector. The differential cross section for the elastic scattering reaction is about the same as for pp-scattering (~100 mb/sr). The main background due to nuclear reactions is outside the energy window of interest. Deuteron–proton (dp) scattering events give an additional signal for hydrogen atoms, so the H/D-ratio can be monitored in parallel. A deuterium detection limit due to accidental coincidences of 3 at-ppm down to less than 1 at-ppm is demonstrated on deuterated polypropylen sheets as well as thick polycarbonate sheets after various stages of coincidence filtering that is possible with our granular detector.
Meson exchange corrections in deep inelastic scattering on deuteron
International Nuclear Information System (INIS)
Kaptari, L.P.; Titov, A.I.
1989-01-01
Starting with the general equations of motion of the nucleons interacting with the mesons the one-particle Schroedinger-like equation for the nucleon wave function and the deep inelastic scattering amplitude with the meson-exchange currents are obtained. Effective pion-, sigma-, and omega-meson exchanges are considered. It is found that the mesonic corrections only partially (about 60%) restore the energy sum rule breaking because of the nucleon off-mass-shell effects in nuclei. This results contradicts with the prediction based on the calculation of the energy sum rule limited by the second order of the nucleon-meson vertex and static approximation. 17 refs.; 3 figs
Tensor polarized deuteron targets for intermediate energy physics experiments
International Nuclear Information System (INIS)
Meyer, W.; Schilling, E.
1985-03-01
At intermediate energies measurements from a tensor polarized deuteron target are being prepared for the following reactions: the photodisintegration of the deuteron, the elastic pion-deuteron scattering and the elastic electron-deuteron scattering. The experimental situation of the polarization experiments for these reactions is briefly discussed in section 2. In section 3 the definitions of the deuteron polarization and the possibilities to determine the vector and tensor polarization are given. Present tensor polarization values and further improvements in this field are reported in section 4. (orig.)
Directory of Open Access Journals (Sweden)
Shimizu Y.
2010-04-01
Full Text Available Measurements of a complete set of deuteron analyzing powers (iT11, T20, T21, T22 for elastic deuteron–proton scattering at 250 MeV/nucleon have been performed with polarized deuteron beams at RIKEN RI Beam Factory. The obtained data are compared with the Faddeev calculations based on the modern nucleon–nucleon forces together with the Tucson-Melbourne’99, and UrbanaIX three nucleon forces.
Energy Technology Data Exchange (ETDEWEB)
Patel, D.; Garg, U. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Joint Institute for Nuclear Astrophysics, University of Notre Dame, Notre Dame, IN 46556 (United States); Itoh, M. [Cyclotron and Radioisotope Center, Tohoku University, Sendai 980-8578 (Japan); Akimune, H. [Department of Physics, Konan University, Kobe 568-8501 (Japan); Berg, G.P.A. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Joint Institute for Nuclear Astrophysics, University of Notre Dame, Notre Dame, IN 46556 (United States); Fujiwara, M. [Research Center for Nuclear Physics, Osaka University, Osaka 567-0047 (Japan); Harakeh, M.N. [Kernfysisch Versneller Instituut, University of Groningen, 9747 AA Groningen (Netherlands); GANIL, CEA/DSM-CNRS/IN2P3, 14076 Caen (France); Iwamoto, C. [Department of Physics, Konan University, Kobe 568-8501 (Japan); Kawabata, T. [Division of Physics and Astronomy, Kyoto University, Kyoto 606-8502 (Japan); Kawase, K. [Japan Atomic Energy Agency, Kyoto 619-0215 (Japan); Matta, J.T. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Joint Institute for Nuclear Astrophysics, University of Notre Dame, Notre Dame, IN 46556 (United States); Murakami, T. [Division of Physics and Astronomy, Kyoto University, Kyoto 606-8502 (Japan); Okamoto, A. [Department of Physics, Konan University, Kobe 568-8501 (Japan); Sako, T. [Japan Atomic Energy Agency, Kyoto 619-0215 (Japan); Schlax, K.W. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Takahashi, F. [Research Center for Nuclear Physics, Osaka University, Osaka 567-0047 (Japan); White, M. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Yosoi, M. [Research Center for Nuclear Physics, Osaka University, Osaka 567-0047 (Japan)
2014-07-30
The excitation of the isoscalar giant monopole resonance (ISGMR) in {sup 208}Pb and {sup 116}Sn has been investigated using small-angle (including 0°) inelastic scattering of 100 MeV/u deuteron and multipole-decomposition analysis (MDA). The extracted strength distributions agree well with those from inelastic scattering of 100 MeV/u α particles. These measurements establish deuteron inelastic scattering at E{sub d}∼100 MeV/u as a suitable probe for extraction of the ISGMR strength with MDA, making feasible the investigation of this resonance in radioactive isotopes in inverse kinematics.
International Nuclear Information System (INIS)
Peterson, G.A.
1989-01-01
We briefly review some of the motivations, early results, and techniques of magnetic elastic and inelastic electron-nucleus scattering. We then discuss recent results, especially those acquired at high momentum transfers. 50 refs., 19 figs
Neutron-deuteron scattering calculations with W-matrix representation of the two-body input
International Nuclear Information System (INIS)
Bartnik, E.A.; Haberzettl, H.; Januschke, T.; Kerwath, U.; Sandhas, W.
1987-05-01
Employing the W-matrix representation of the partial-wave T matrix introduced by Bartnik, Haberzettl, and Sandhas, we show for the example of the Malfliet-Tjon potentials I and III that the single-term separable part of the W-matrix representation, when used as input in three-nucleon neutron-deuteron scattering calculations, is fully capable of reproducing the exact results obtained by Kloet and Tjon. This approximate two-body input not only satisfies the two-body off-shell unitarity relation but, moreover, it also contains a parameter which may be used in optimizing the three-body data. We present numerical evidence that there exists a variational (minimum) principle for the determination of the three-body binding energy which allows one to choose this parameter also in the absence of an exact reference calculation. Our results for neutron-deuteron scattering show that it is precisely this choice of the parameter which provides optimal scattering data. We conclude that the W-matrix approach, despite its simplicity, is a remarkably efficient tool for high-quality three-nucleon calculations. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Franz Gross, Alfred Stadler
2010-09-01
We present the effective range expansions for the 1S0 and 3S1 scattering phase shifts, and the relativistic deuteron wave functions that accompany our recent high precision fits (with \\chi^2/N{data} \\simeq 1) to the 2007 world np data below 350 MeV. The wave functions are expanded in a series of analytical functions (with the correct asymptotic behavior at both large and small arguments) that can be Fourier-transformed from momentum to coordinate space and are convenient to use in any application. A fortran subroutine to compute these wave functions can be obtained from the authors.
Scattering length measurements from radiative pion capture and neutron-deuteron breakup
International Nuclear Information System (INIS)
Gibson, B.F.; Tornow, W.; Carman, T.S.
1997-07-01
The neutron-neutron and neutron-proton 1 S 0 scattering lengths a nn and a np , respectively, were determined simultaneously from the neutron-deuteron breakup reaction. Their comparison with the recommended values obtained from two body reactions gives a measure of the importance of three-nucleon force effects in the three-nucleon continuum. In order to check on the result obtained for a nn from the two-body π - -d capture reaction, a new measurement was performed at LANL. Preliminary results of the three experiments are given
Scattering length measurements from radiative pion capture and neutron-deuteron breakup
Energy Technology Data Exchange (ETDEWEB)
Tornow, W.; Chen, Q. [Duke Univ., Durham, NC (United States). Dept. of Physics; Carman, T.S. [Lawrence Livermore National Lab., CA (United States). Program for Climate Model Diagnosis and Intercomparison] [and others
1998-03-02
The neutron-neutron and neutron-proton {sup 1}S{sub 0} scattering lengths a{sub nn} and a{sub np}, respectively, were determined simultaneously from the neutron-deuteron breakup reaction. Their comparison with the recommended values obtained from ``two-body`` reactions gives a measure of the importance of three-nucleon force effects in the three-nucleon continuum. In order to check on the result obtained for a{sub nn} from the ``two-body`` {pi}{sup -}-d capture reaction, a new measurement was performed at LANL. Preliminary results of the three experiments are given. (orig.). 5 refs.
International Nuclear Information System (INIS)
Nardi, V.; Bostick, W.; Prior, W.; Feugeas, J.; Bortolotti, A.
1982-01-01
A detailed analysis has been completed on the internal structure of ions and electron beams which are efected, along the system axis, in opposite directions (0 0 and 180 0 ). An image (contact print) of plasmoids which emit MeV deuterons is formed by the deuteron emission and it is revealed by etching deuteron tracks in a target of plastic material (CR-39). Ion-imaging with different energy filters discriminates between tracks of plasmoid ions and tracks of charged products of D-D fusion reactions. Ions-imaging can also discriminate plasmoid deuterons from MeV deuterons of a directed beam. (L.C.) [pt
First-order neutron-deuteron scattering in a three-dimensional approach
International Nuclear Information System (INIS)
Topolnicki, K.; Golak, J.; Skibinski, R.; Witala, H.; Bertulani, C.A.
2015-01-01
The description of the neutron-deuteron scattering process has been possible using the partial wave approach since the 1980s (Few-Body Syst. 3, 123 (1988); Phys. Rep. 274, 107 (1996); Acta Phys. Pol. B 28, 1677 (1997)). In recent years the so-called ''three-dimensional'' formalism was developed, where the calculations are performed with operators acting directly on the three-dimensional degrees of freedom of the nucleons. This approach avoids a tedious step of the classical calculations, the partial wave decomposition of operators, and in this paper is applied to the neutron-deuteron scattering process. The calculations presented here are a first step toward a new calculation scheme that would make it possible to easily produce precise predictions for a wide range of nuclear force models. This paper is a continuation of the work presented in Eur. Phys. J. A 43, 339 (2010) where the breakup channel was considered in detail. The theoretical formulation used in this paper is very closely related to the formalism introduced in Eur. Phys. J. A 43, 339 (2010) and Phys. Rev. C 68, 054003 (2003), however, we work directly with the matrix representation of operators in the joined isospin-spin space of the three-nucleon system and use only the driving term of the three-nucleon Faddeev equations. This greatly simplifies the numerical realization of the calculation and allows us to consider also the elastic channel of the reaction. (orig.)
International Nuclear Information System (INIS)
Babenko, V. A.; Petrov, N. M.
2008-01-01
The correlation between the root-mean-square matter radius of the deuteron, r m , and its effective radius, ρ, is investigated. A parabolic relationship between these two quantities makes it possible to determine the root-mean-square radius r m to within 0.01% if the effective radius ρ is known. The matter (r m ), structural (r d ), and charge (r ch ) radii of the deuteron are found with the aid of modern experimental results for phase shifts from the SAID nucleon-nucleon database, and their values are fully consistent with their counterparts deduced by using the experimental value of the effective deuteron radius due to Borbely and his coauthors. The charge-radius value of 2.124(6) fm, which was obtained with the aid of the SAID nucleon-nucleon database, and the charge-radius value of 2.126(12) fm, which was obtained with the aid of the experimental value of the effective radius ρ, are in very good agreement with the present-day chargeradius value of 2.128(11) fm, which was deduced by Sick and Trautmann by processing world-average experimental data on elastic electron scattering by deuterons with allowance for Coulomb distortions.
International Nuclear Information System (INIS)
Peter Bosted; M. E. Christy
2007-01-01
An empirical fit is described to measurements of inclusive inelastic electron-deuteron cross sections in the kinematic range of four-momentum transfer 0 (le) Q 2 2 and final state invariant mass 1.2 p of longitudinal to transverse cross sections for the proton, and the assumption R p =R n . The underlying fit parameters describe the average cross section for proton and neutron, with a plane-wave impulse approximation (PWIA) used to fit to the deuteron data. Pseudo-data from MAID 2007 were used to constrain the average nucleon cross sections for W<1.2 GeV. The mean deviation of data from the fit is 3%, with less than 5% of the data points deviating from the fit by more than 10%
International Nuclear Information System (INIS)
Bosted, P. E.; Christy, M. E.
2008-01-01
An empirical fit is described to measurements of inclusive inelastic electron-deuteron cross sections in the kinematic range of four-momentum transfer 0≤Q 2 2 and final state invariant mass 1.1 p of longitudinal to transverse cross sections for the proton, and the assumption R p =R n . The underlying fit parameters describe the average cross section for a free proton and a free neutron, with a plane-wave impulse approximation used to fit to the deuteron data. Additional fit parameters are used to fill in the dip between the quasi-elastic peak and the Δ(1232) resonance. The mean deviation of data from the fit is 3%, with less than 4% of the data points deviating from the fit by more than 10%
Flavour Separation of Helicity Distributions from Deep Inelastic Muon-Deuteron Scattering
Alekseev, M.; Alexandrov, Yu.; Alexeev, G.D.; Amoroso, A.; Austregesilo, A.; Badelek, B.; Balestra, F.; Ball, J.; Barth, J.; Baum, G.; Bedfer, Y.; Bernhard, J.; Bertini, R.; Bettinelli, M.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, F.; Bravar, A.; Bressan, A.; Brona, G.; Burtin, E.; Bussa, M.P.; Chapiro, A.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Colantoni, M.; Crespo, M.L.; Dalla Torre, S.; Dafni, T.; Das, S.; Dasgupta, S.S.; Denisov, O.Yu.; Dhara, L.; Diaz, V.; Dinkelbach, A.M.; Donskov, S.V.; Doshita, N.; Duic, V.; Dunnweber, W.; Efremov, A.; El Alaoui, A.; Eversheim, P.D.; Eyrich, W.; Faessler, M.; Ferrero, A.; Finger, M.; Finger, M.; Fischer, H.; Franco, C.; Friedrich, J.M.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.P.; Gazda, R.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gobbo, B.; Goertz, S.; Grabmuller, S.; Grajek, O.A.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Haas, F.; Hagemann, R.; von Harrach, D.; Hasegawa, T.; Heckmann, J.; Heinsius, F.H.; Hermann, R.; Herrmann, F.; Hess, C.; Hinterberger, F.; Horikawa, N.; Hoppner, Ch.; d'Hose, N.; Ilgner, C.; Ishimoto, S.; Ivanov, O.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jasinski, P.; Jegou, G.; Joosten, R.; Kabuss, E.; Kafer, W.; Kang, D.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu.A.; Kiefer, J.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koblitz, S.; Koivuniemi, J.H.; Kolosov, V.N.; Komissarov, E.V.; Kondo, K.; Konigsmann, K.; Konopka, R.; Konorov, I.; Konstantinov, V.F.; Korzenev, A.; Kotzinian, A.M.; Kouznetsov, O.; Kowalik, K.; Kramer, M.; Kral, A.; Kroumchtein, Z.V.; Kuhn, R.; Kunne, F.; Kurek, K.; Le Goff, J.M.; Lednev, A.A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Liska, T.; Maggiora, A.; Maggiora, M.; Magnon, A.; Mallot, G.K.; Mann, A.; Marchand, C.; Marroncle, J.; Martin, A.; Marzec, J.; Massmann, F.; Matsuda, T.; Maximov, A.N.; Meyer, W.; Michigami, T.; Mikhailov, Yu.V.; Moinester, M.A.; Mutter, A.; Nagaytsev, A.; Nagel, T.; Nassalski, J.; Negrini, S.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.I.; Olshevsky, A.G.; Ostrick, M.; Padee, A.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Pawlukiewicz-Kaminska, B.; Perevalova, E.; Pesaro, G.; Peshekhonov, D.V.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.A.; Pontecorvo, G.; Pretz, J.; Quintans, C.; Rajotte, J.F.; Ramos, S.; Rapatsky, V.; Reicherz, G.; Reggiani, D.; Richter, A.; Robinet, F.; Rocco, E.; Rondio, E.; Ryabchikov, D.I.; Samoylenko, V.D.; Sandacz, A.; Santos, H.; Sapozhnikov, M.G.; Sarkar, S.; Savin, I.A.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schmitt, L.; Schroder, W.; Shevchenko, O.Yu.; Siebert, H.W.; Silva, L.; Sinha, L.; Sissakian, A.N.; Slunecka, M.; Smirnov, G.I.; Sosio, S.; Sozzi, F.; Srnka, A.; Stolarski, M.; Sulc, M.; Sulej, R.; Takekawa, S.; Tessaro, S.; Tessarotto, F.; Teufel, A.; Tkatchev, L.G.; Venugopal, G.; Virius, M.; Vlassov, N.V.; Vossen, A.; Weitzel, Q.; Wenzl, K.; Windmolders, R.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zhao, J.; Zhuravlev, N.; Zvyagin, A.
2009-01-01
We present a LO evaluation of helicity densities of valence, \\Delta u_v+\\Delta d_v, non-strange sea, \\Delta\\bar{u}+\\Delta\\bar{d}, and strange quarks, \\Delta s (assumed to be equal to \\Delta\\bar{s}). They have been obtained from the inclusive asymmetry A_{3,d} and the semi-inclusive asymmetries A^{\\pi+}_{1,d}, A^{\\pi-}_{1,d}, A^{K+}_{1,d}, A^{K-}_{1,d} measured in polarised deep inelastic muon-deuteron scattering. The full deuteron statistics of COMPASS (years 2002-2004 and 2006) has been used. The data cover the range Q^2 > 1 (GeV/c)^2 and 0.004
Adolph, C; Akhunzyanov, R; Alexeev, M G; Alexeev, G D; Amoroso, A; Andrieux, V; Anfimov, N V; Anosov, V; Augsten, K; Augustyniak, W; Austregesilo, A; Azevedo, C D R; Badełek, B; Balestra, F; Ball, M; Barth, J; Beck, R; Bedfer, Y; Bernhard, J; Bicker, K; Bielert, E R; Birsa, R; Bodlak, M; Bordalo, P; Bradamante, F; Braun, C; Bressan, A; Buchele, M; Chang, W-C; Chatterjee, C; Chiosso, M; Choi, I; Chung, S-U; Cicuttin, A; Crespo, M L; Curiel, Q; Dalla Torre, S; Dasgupta, S S; Dasgupta, S; Denisov, O Yu; Dhara, L; Donskov, S V; Doshita, N; Dreisbach, Ch; Duic, V; Dunnweber, W; Dziewiecki, M; Efremov, A; Eversheim, P D; Eyrich, W; Faessler, M; Ferrero, A; Finger, M; Finger jr, M; Fischer, H; Franco, C; du Fresne von Hohenesche, N; Friedrich, J M; Frolov, V; Fuchey, E; Gautheron, F; Gavrichtchouk, O P; Gerassimov, S; Giarra, J; Giordano, F; Gnesi, I; Gorzellik, M; Grabmuller, S; Grasso, A; Grosse Perdekamp, M; Grube, B; Grussenmeyer, T; Guskov, A; Haas, F; Hahne, D; Hamar, G; von Harrach, D; Heinsius, F H; Heitz, R; Herrmann, F; Horikawa, N; d’Hose, N; Hsieh, C-Y; Huber, S; Ishimoto, S; Ivanov, A; Ivanshin, Yu; Iwata, T; Jary, V; Joosten, R; Jorg, P; Kabuß, E; Ketzer, B; Khaustov, G V; Khokhlov, Yu A; Kisselev, Yu; Klein, F; Klimaszewski, K; Koivuniemi, J H; Kolosov, V N; Kondo, K; Konigsmann, K; Konorov, I; Konstantinov, V F; Kotzinian, A M; Kouznetsov, O M; Kramer, M; Kremser, P; Krinner, F; Kroumchtein, Z V; Kulinich, Y; Kunne, F; Kurek, K; Kurjata, R P; Lednev, A A; Lehmann, A; Levillain, M; Levorato, S; Lian, Y-S; Lichtenstadt, J; Longo, R; Maggiora, A; Magnon, A; Makins, N; Makke, N; Mallot, G K; Marianski, B; Martin, A; Marzec, J; Matousek, J; Matsuda, H; Matsuda, T; Meshcheryakov, G V; Meyer, M; Meyer, W; Mikhailov, Yu V; Mikhasenko, M; Mitrofanov, E; Mitrofanov, N; Miyachi, Y; Nagaytsev, A; Nerling, F; Neyret, D; Novy, J; Nowak, W-D; Nukazuka, G; Nunes, A S; Olshevsky, A G; Orlov, I; Ostrick, M; Panzieri, D; Parsamyan, B; Paul, S; Peng, J-C; Pereira, F; Pesek, M; Peshekhonov, D V; Pierre, N; Platchkov, S; Pochodzalla, J; Polyakov, V A; Pretz, J; Quaresma, M; Quintans, C; Ramos, S; Regali, C; Reicherz, G; Riedl, C; Roskot, M; Rossiyskaya, N S; Ryabchikov, D I; Rybnikov, A; Rychter, A; Salac, R; Samoylenko, V D; Sandacz, A; Santos, C; Sarkar, S; Savin, I A; Sawada, T; Sbrizzai, G; Schiavon, P; Schmidt, K; Schmieden, H; Schonning, K; Seder, E; Selyunin, A; Silva, L; Sinha, L; Sirtl, S; Slunecka, M; Smolik, J; Srnka, A; Steffen, D; Stolarski, M; Subrt, O; Sulc, M; Suzuki, H; Szabelski, A; Szameitat, T; Sznajder, P; Takekawa, S; Tasevsky, M; Tessaro, S; Tessarotto, F; Thibaud, F; Thiel, A; Tosello, F; Tskhay, V; Uhl, S; Veloso, J; Virius, M; Vondra, J; Wallner, S; Weisrock, T; Wilfert, M; ter Wolbeek, J; Zaremba, K; Zavada, P; Zavertyaev, M; Zemlyanichkina, E; Zhuravlev, N; Ziembicki, M; Zink, A
2016-01-01
Single hadron azimuthal asymmetries in the cross sections of positive and negative hadron production in muon semi-inclusive deep inelastic scattering off longitudinally polarised deuterons are determined using the 2006 COMPASS data and also all deuteron COMPASS data. For each hadron charge, the dependence of the azimuthal asymmetry on the hadron azimuthal angle $\\phi$ is obtained by means of a five-parameter fitting function that besides a $\\phi$-independent term includes four modulations predicted by theory: $\\sin\\phi$, $\\sin 2 \\phi$, $\\sin 3\\phi$ and $\\cos\\phi$. The amplitudes of the five terms have been first extracted for the data integrated over all kinematic variables. In further fits, the $\\phi$-dependence is determined as a function of one of three kinematic variables (Bjorken-$x$, fractional energy of virtual photon taken by the outgoing hadron and hadron transverse momentum), while disregarding the other two. Except the $\\phi$-independent term, all the modulation amplitudes are very small, and no cl...
Measurements of T20 in backward elastic dp scattering at deuteron momenta 3.5--6 GeV/c
International Nuclear Information System (INIS)
Azhgirey, L.S.; Borzunov, Y.T.; Chernykh, E.V.; Golovanov, L.B.; Ignatenko, M.A.; Kobushkin, A.P.; Ladygin, V.P.; Manyakov, P.K.; Moroz, N.S.; Nedev, S.; Penchev, L.; Perdrisat, C.F.; Piskunov, N.M.; Punjabi, V.; Rukoyatkin, P.A.; Sitnik, I.M.; Stoletov, G.D.; Strokovsky, E.A.; Svetov, A.L.; Syamtomov, A.I.; Tsvinev, A.P.; Vikhrov, V.V.; Vizireva, L.; Zaporozhets, S.A.
1995-01-01
Polarization phenomena in backward elastic dp scattering were studied with a view to reconstructing the deuteron wave-function components. Experimental data disagree with predictions based on the impulse approximation which suggests that the wave function may have more than two components. (AIP) copyright 1995 American Institute of Physics
International Nuclear Information System (INIS)
Santoso, B.
1976-01-01
Green Lippmann-Schwinger functions operator representations, derivation of perturbation method using Green function and atom electron scattering, are discussed. It is concluded that by using complex coordinate places where resonances occur, can be accurately identified. The resonance can be processed further for practical purposes, for example for the separation of atom. (RUW)
Parity violating electron scattering
International Nuclear Information System (INIS)
McKeown, R.D.
1990-01-01
Previous measurements of parity violation in electron scattering are reviewed with particular emphasis on experimental techniques. Significant progress in the attainment of higher precision is evident in these efforts. These pioneering experiments provide a basis for consideration of a future program of such measurements. In this paper some future plans and possibilities in this field are discussed
Deuteron disintegration in the neutrino scattering reaction ν + d → ν + p + n
International Nuclear Information System (INIS)
Rekalo, M.P.; Gakh, G.I.; Rekalo, A.P.
1984-01-01
General dependence on vector and tensor deutron polarizations of differential cross section of deuteron disintegration in the reaction of neutrino scattering V+d→ν+pν conditioned by neutral weak current is disclosed. Using locality of weak neutrino interaction with hadrons the dependence of differential cross section and their asymmetries conditioned by polarization of the target on two of five kinematic variables characterizing the ν+d→ν+p+n process and namely on azimuthal angle phi and parameter x associated with the degree of linear polarization of virtual Z-boson is established. Spin structure of vector and axial parts of neutral hadron currrent for the Z+d→p+n reaction is determined. It is shown that threshold amplitude of the Z+d→p+n reaction in the general case is characterized by five vector and five axial formfactors
Alekseev, M G; Alexandrov, Yu; Alexeev, G D; Amoroso, A; Austregesilo, A; Badełek, B; Balestra, F; Barth, J; Baum, G; Bedfer, Y; Bernhard, J; Bertini, R; Bettinelli, M; Birsa, R; Bisplinghoff, J; Bordalo, P; Bradamante, F; Bravar, A; Bressan, A; Brona, G; Burtin, E; Bussa, M P; Chaberny, D; Chiosso, M; Chung, S U; Cicuttin, A; Colantoni, M; Crespo, M L; Dalla Torre, S; Das, S; Dasgupta, S S; Denisov, O Yu; Dhara, L; Diaz, V; Donskov, S V; Doshita, N; Duic, V; Dünnweber, W; Efremov, A; El Alaoui, A; Eversheim, P D; Eyrich, W; Faessler, M; Ferrero, A; Filin, A; Finger, M; Finger, M Jr; Fischer, H; Franco, C; Friedrich, J M; Garfagnini, R; Gautheron, F; Gavrichtchouk, O P; Gazda, R; Gerassimov, S; Geyer, R; Giorgi, M; Gnesi, I; Gobbo, B; Goertz, S; Grabmüller, S; Grasso, A; Grube, B; Gushterski, R; Guskov, A; Haas, F; von Harrach, D; Hasegawa, T; Heinsius, F H; Herrmann, F; Heß, C; Hinterberger, F; Horikawa, N; Höppner, Ch; d’Hose, N; Ilgner, C; Ishimoto, S; Ivanov, O; Ivanshin, Yu; Iwata, T; Jahn, R; Jasinski, P; Jegou, G; Joosten, R; Kabuß, E; Kang, D; Ketzer, B; Khaustov, G V; Khokhlov, Yu A; Kisselev, Yu; Klein, F; Klimaszewski, K; Koblitz, S; Koivuniemi, J H; Kolosov, V N; Kondo, K; Königsmann, K; Konopka, R; Konorov, I; Konstantinov, V F; Korzenev, A; Kotzinian, A M; Kouznetsov, O; Kowalik, K; Krämer, M; Kral, A; Kroumchtein, Z V; Kuhn, R; Kunne, F; Kurek, K; Lauser, L; Le Goff, J M; Lednev, A A; Lehmann, A; Levorato, S; Lichtenstadt, J; Liska, T; Maggiora, A; Maggiora, M; Magnon, A; Mallot, G K; Mann, A; Marchand, C; Martin, A; Marzec, J; Massmann, F; Matsuda, T; Meyer, W; Michigami, T; Mikhailov, Yu V; Moinester, M A; Mutter, A; Nagaytsev, A; Nagel, T; Nassalski, J; Negrini, T; Nerling, F; Neubert, S; Neyret, D; Nikolaenko, V I; Nunes, A S; Olshevsky, A G; Ostrick, M; Padee, A; Panknin, R; Panzieri, D; Parsamyan, B; Paul, S; Pawlukiewicz-Kaminska, B; Perevalova, E; Pesaro, G; Peshekhonov, D V; Piragino, G; Platchkov, S; Pochodzalla, J; Polak, J; Polyakov, V A; Pontecorvo, G; Pretz, J; Quintans, C; Rajotte, J F; Ramos, S; Rapatsky, V; Reicherz, G; Richter, A; Robinet, F; Rocco, E; Rondio, E; Ryabchikov, D I; Samoylenko, V D; Sandacz, A; Santos, H; Sapozhnikov, M G; Sarkar, S; Savin, I A; Sbrizzai, G; Schiavon, P; Schill, C; Schlüter, T; Schmitt, L; Schopferer, S; Schröder, W; Shevchenko, O Yu; Siebert, H W; Silva, L; Sinha, L; Sissakian, A N; Slunecka, M; Smirnov, G I; Sosio, S; Sozzi, F; Srnka, A; Stolarski, M; Sulc, M; Sulej, R; Takekawa, S; Tessaro, S; Tessarotto, F; Teufel, A; Tkatchev, L G; Uhl, S; Uman, I; Virius, M; Vlassov, N V; Vossen, A; Weitzel, Q; Windmolders, R; Wislicki, W; Wollny, H; Zaremba, K; Zavertyaev, M; Zemlyanichkina, E; Ziembicki, M; Zhao, J; Zhuravlev, N; Zvyagin, A
2010-01-01
Azimuthal asymmetries in semi-inclusive production of positive (h^+) and negative hadrons (h^-) have been measured by scattering 160 GeV muons off longitudinally polarised deuterons at CERN. The asymmetries were decomposed in several terms according to their expected modulation in the azimuthal angle phi of the outgoing hadron. Each term receives contributions from one or several spin and transverse-momentum-dependent parton distribution and fragmentation functions. The amplitudes of all phi-modulation terms of the hadron asymmetries integrated over the kinematic variables are found to be consistent with zero within statistical errors, while the constant terms are nonzero and equal for h^+ and h^- within the statistical errors. The dependencies of the phi-modulated terms versus the Bjorken momentum fraction x, the hadron fractional momentum z, and the hadron transverse momentum p_h^T were studied. The x dependence of the constant terms for both positive and negative hadrons is in agreement with the longitudin...
Tagged spectator deep-inelastic scattering off the deuteron as a tool to study neutron structure
International Nuclear Information System (INIS)
Cosyn, W.; Sargsian, M.
2016-01-01
We give an overview of a model to describe deep-inelastic scattering (DIS) off the deuteron with a spectator proton (e+d → e'+X+p s ), based on the virtual nucleon approximation (VNA). The model accounts for the final-state interactions (FSI) of the DIS debris with the spectator proton. Values of the rescattering cross section are obtained by fits to high-momentum spectator data. By using the so-called 'pole extrapolation' method, free neutron structure functions can be obtained by extrapolating low-momentum spectator proton data to the on-shell neutron pole. We apply this method to the BONuS data set and find a surprising Bjorken x dependence, indicating a possible rise of the neutron to proton structure function ratio at high x. (authors)
International Nuclear Information System (INIS)
McCarthy, I.E.
1991-07-01
The coupled-channels-optical method has been implemented using two different approximations to the optical potential. The half-on-shell optical potential involves drastic approximations for numerical feasibility but still gives a good semiquantitative description of the effect of uncoupled channels on electron scattering from hydrogen, helium and sodium. The distorted-wave optical potential makes no approximations other than the weak coupling approximation for uncoupled channels. In applications to hydrogen and sodium it shows promise of describing scattering phenomena excellently at all energies. 27 refs., 5 figs
Deuteron polarizability and S-wave π+d scattering at energies below 1 keV
International Nuclear Information System (INIS)
Pupyshev, V.V.
1987-01-01
The influence of deuteron polarizability on the S-wave π + d-scattering in a low-energy limit is explored in the framework of the variable phase method. It is shown that the nonoscillating part of the S-wave cross section of π + d-scattering has a deep and sharp minimum in the energy region ∼ 0.4 keV
Effect of Δ-isobar excitation on spin-dependent observables of elastic nucleon-deuteron scattering
International Nuclear Information System (INIS)
Nemoto, S.; Oryu, S.; Chmielewski, K.; Sauer, P.U.
2000-01-01
Δ-isobar excitation in the nuclear medium yields an effective three-nucleon force. A coupled-channel formulation with Δ-isobar excitation developed previously is used. The three-particle scattering equations are solved by a separable expansion of the two-baryon transition matrix for elastic nucleon-deuteron scattering. The effect of Δ-isobar excitation on the spin-dependent observables is studied at energies above 50 MeV nucleon lab energy. (author)
Electron scattering off nuclei
International Nuclear Information System (INIS)
Gattone, A.O.
1989-01-01
Two recently developed aspects related to the scattering of electrons off nuclei are presented. On the one hand, a model is introduced which emphasizes the relativistic aspects of the problem in the impulse approximation, by demanding strict maintenance of the algebra of the Poincare group. On the other hand, the second model aims at a more sophisticated description of the nuclear response in the case of collective excitations. Basically, it utilizes the RPA formalism with a new development which enables a more careful treatment of the states in the continuum as is the case for the giant resonances. Applications of both models to the description of elastic scattering, inelastic scattering to discrete levels, giant resonances and the quasi-elastic region are discussed. (Author) [es
Neutron-deuteron elastic scattering and breakup reactions below 20 MeV
Energy Technology Data Exchange (ETDEWEB)
Howell, C.R.; Tornow, W.; Pfuetzner, H.G.; Roberts, M.L.; Murphy, K.; Felsher, P.D.; Weisel, G.J.; Mertens, G.; Walter, R.L. (Duke Univ. and Triangle Universities Nuclear Lab., Durham, NC (USA)); Lambert, J.M.; Treado, P.A. (Physics Dept., Georgetown Univ., Washington, DC (USA)); Slaus, I. (Rudjer Boskovic Inst., Zagreb (Yugoslavia))
1991-05-01
In this paper we review the results of a series of high-accuracy measurements on the neutron-deuteron (n-d) scattering system at incident neutron energies below 20 MeV. These measurements were designed to: 1) provide data of sufficient accuracy to be used to refine the parametrization of the nucleon-nucleon force, 2) to test the reaction dynamics in the ''rigorous'' calculations of three-nucleon (3N) breakup reactions, and 3) identify 3N scattering observables that are specifically sensitive to three-nucleus forces and/or off-shell effects. At TUNL we have measured vector analyzing powers A{sub y}({theta}) for n-d elastic scattering and the breakup reaction to an accuracy better than {+-}0.005 and {+-}0.020, respectively. Recent results on items 1) and 2) will be presented. Also, results of cross-section measurements for n-d and p-d breakup will be compared to a ''rigorous'' 3N calculation. (orig.).
Neutron-deuteron elastic scattering and breakup reactions below 20 MeV
International Nuclear Information System (INIS)
Howell, C.R.; Tornow, W.; Pfuetzner, H.G.; Roberts, M.L.; Murphy, K.; Felsher, P.D.; Weisel, G.J.; Mertens, G.; Walter, R.L.; Lambert, J.M.; Treado, P.A.; Slaus, I.
1991-01-01
In this paper we review the results of a series of high-accuracy measurements on the neutron-deuteron (n-d) scattering system at incident neutron energies below 20 MeV. These measurements were designed to: 1) provide data of sufficient accuracy to be used to refine the parametrization of the nucleon-nucleon force, 2) to test the reaction dynamics in the ''rigorous'' calculations of three-nucleon (3N) breakup reactions, and 3) identify 3N scattering observables that are specifically sensitive to three-nucleus forces and/or off-shell effects. At TUNL we have measured vector analyzing powers A y (θ) for n-d elastic scattering and the breakup reaction to an accuracy better than ±0.005 and ±0.020, respectively. Recent results on items 1) and 2) will be presented. Also, results of cross-section measurements for n-d and p-d breakup will be compared to a ''rigorous'' 3N calculation. (orig.)
Exclusive nuclear reactions: Can you count on the deuteron?
International Nuclear Information System (INIS)
Holt, R.J.
1991-01-01
Three of the simplest nuclear reactions -- (1) electron-deuteron elastic scattering, (2) electro-disintegration of the deuteron near threshold and at high momentum transfer, and (3) photodisintegration of the deuteron at high energy -- were believed to have unique signatures for OCD effects in nuclei. The progress in the past few years with regard to these reactions will be traced and the results will be compared with recent theoretical predictions. 36 refs., 12 figs., 1 tab
Electron scattering for exotic nuclei
Indian Academy of Sciences (India)
2014-11-04
Nov 4, 2014 ... A brand-new electron scattering facility, the SCRIT Electron Scattering Facility, will soon start its operation at RIKEN RI Beam Factory, Japan. This is the world's first electron scattering facility dedicated to the structure studies of short-lived nuclei. The goal of this facility is to determine the charge density ...
International Nuclear Information System (INIS)
Tornow, W.; Braun, R.T.; Witala, H.
1996-01-01
We review published analyses of the final-state-interaction enhancement observed in proton energy distributions obtained from kinematically incomplete neutron-deuteron breakup experiments. We compare the results derived from these analyses for the neutron-neutron scattering length, a nn with our results based on a rigorous treatment of the three-nucleon Faddeev equations in conjunction with the use of realistic nucleon-nucleon potentials. Our values for a nn deviate outside the quoted uncertainties from the ones obtained in the previous analyses where simplified nucleon-nucleon interaction models were employed. In contrast to the previous determinations, the present results for a nn are in clear disagreement with the values for a nn based on π - -deuteron capture experiments. Unless inconsistencies in the experimental neutron-deuteron breakup data at low energies can be resolved and the influence of possible three-nucleon-force effects can be reliably determined, we recommend that one not resort to the kinematically incomplete neutron-deuteron breakup reaction as a tool for determining a quantity as important for nuclear and particle physics as is the neutron-neutron scattering length a nn . (author)
Alekseev, M G; Alexandrov, Yu; Alexeev, G D; Amoroso, A; Austregesilo, A; Badelek, B; Balestra, F; Barth, J; Baum, G; Bedfer, Y; Bernhard, J; Bertini, R; Bettinelli, M; Birsa, R; Bisplinghoff, J; Bordalo, P; Bradamante, F; Bravar, A; Bressan, A; Brona, G; Burtin, E; Bussa, M P; Chaberny, D; Chiosso, M; Chung, S U; Cicuttin, A; Colantoni, M; Crespo, M L; Dalla Torre, S; Das, S; Dasgupta, S S; Denisov, O Yu; Dhara, L; Diaz, V; Donskov, S V; Doshita, N; Duic, V; Dunnweber, W; Efremov, A; El Alaoui, A; Eversheim, P D; Eyrich, W; Faessler, M; Ferrero, A; Filin, A; Finger, M; Finger, M., Jr; Fischer, H; Franco, C; Friedrich, J M; Garfagnini, R; Gautheron, F; Gavrichtchouk, O P; Gazda, R; Gerassimov, S; Geyer, R; Giorgi, M; Gnesi, I; Gobbo, B; Goertz, S; Grabmuller, S; Grasso, A; Grube, B; Gushterski, R; Guskov, A; Haas, F; von Harrach, D; Hasegawa, T; Heinsius, F H; Herrmann, F; Hess, C; Hinterberger, F; Horikawa, N; Hoppner, Ch; d'Hose, N; Ilgner, C; Ishimoto, S; Ivanov, O; Ivanshin, Yu; Iwata, T; Jahn, R; Jasinski, P; Jegou, G; Joosten, R; Kabuss, E; Kang, D; Ketzer, B; Khaustov, G V; Khokhlov, Yu.A; Kisselev, Yu; Klein, F; Klimaszewski, K; Koblitz, S; Koivuniemi, J H; Kolosov, V N; Kondo, K; Konigsmann, K; Konopka, R; Konorov, I; Konstantinov, V F; Korzenev, A; Kotzinian, A M; Kouznetsov, O; Kowalik, K; Kramer, M; Kral, A; Kroumchtein, Z V; Kuhn, R; Kunne, F; Kurek, K; Lauser, L; Le Goff, J M; Lednev, A A; Lehmann, A; Levorato, S; Lichtenstadt, J; Liska, T; Maggiora, A; Maggiora, M; Magnon, A; Makke, N; Mallot, G K; Mann, A; Marchand, C; Martin, A; Marzec, J; Massmann, F; Matsuda, T; Meyer, W; Michigami, T; Mikhailov, Yu.V; Moinester, M A; Mutter, A; Nagaytsev, A; Nagel, T; Nassalski, J; Negrini, T; Nerling, F; Neubert, S; Neyret, D; Nikolaenko, V I; Nunes, A S; Olshevsky, A G; Ostrick, M; Padee, A; Panknin, R; Panzieri, D; Parsamyan, B; Paul, S; Pawlukiewicz-Kaminska, B; Perevalova, E; Pesaro, G; Peshekhonov, D V; Piragino, G; Platchkov, S; Pochodzalla, J; Polak, J; Polyakov, V A; Pontecorvo, G; Pretz, J; Quintans, C; Rajotte, J F; Ramos, S; Rapatsky, V; Reicherz, G; Richter, A; Robinet, F; Rocco, E; Rondio, E; Ryabchikov, D I; Samoylenko, V D; Sandacz, A; Santos, H; Sapozhnikov, M G; Sarkar, S; Savin, I A; Sbrizzai, G; Schiavon, P; Schill, C; Schluter, T; Schmitt, L; Schopferer, S; Schroder, W; Shevchenko, O Yu; Siebert, H W; Silva, L; Sinha, L; Sissakian, A N; Slunecka, M; Smirnov, G I; Sosio, S; Sozzi, F; Srnka, A; Stolarski, M; Sulc, M; Sulej, R; Takekawa, S; Tessaro, S; Tessarotto, F; Teufel, A; Tkatchev, L G; Uhl, S; Uman, I; Virius, M; Vlassov, N V; Vossen, A; Weitzel, Q; Windmolders, R; Wislicki, W; Wollny, H; Zaremba, K; Zavertyaev, M; Zemlyanichkina, E; Ziembicki, M; Zhao, J; Zhuravlev, N; Zvyagin, A
2010-01-01
Double-spin asymmetries for production of charged pions and kaons in semi-inclusive deep-inelastic muon scattering have been measured by the COMPASS experiment at CERN. The data, obtained by scattering a 160 GeV muon beam off a longitudinally polarised NH_3 target, cover a range of the Bjorken variable x between 0.004 and 0.7. A leading order evaluation of the helicity distributions for the three lightest quarks and antiquark flavours derived from these asymmetries and from our previous deuteron data is presented. The resulting values of the sea quark distributions are small and do not show any sizable dependence on x in the range of the measurements. No significant difference is observed between the strange and antistrange helicity distributions, both compatible with zero. The integrated value of the flavour asymmetry of the helicity distribution of the light-quark sea, \\Delta u-bar - \\Delta d-bar, is found to be slightly positive, about 1.5 standard deviations away from zero.
International Nuclear Information System (INIS)
Alekseev, M.G.; Colantoni, M.; Maggiora, A.; Alexakhin, V.Yu.; Alexeev, G.D.; Efremov, A.; Finger, M.; Gavrichtchouk, O.P.; Gushterski, R.; Guskov, A.; Ivanov, O.; Ivanshin, Yu.; Kroumchtein, Z.V.; Nagaytsev, A.; Olshevsky, A.G.; Perevalova, E.; Peshekhonov, D.V.; Pontecorvo, G.; Rapatsky, V.; Sapozhnikov, M.G.; Savin, I.A.; Shevchenko, O.Yu.; Sissakian, A.N.; Slunecka, M.; Smirnov, G.I.; Tkatchev, L.G.; Vlassov, N.V.; Zemlyanichkina, E.; Zhuravlev, N.; Alexandrov, Yu.; Zavertyaev, M.; Amoroso, A.; Balestra, F.; Bertini, R.; Bussa, M.P.; Chiosso, M.; Garfagnini, R.; Gnesi, I.; Grasso, A.; Kotzinian, A.M.; Maggiora, M.; Parsamyan, B.; Piragino, G.; Rocco, E.; Sosio, S.; Austregesilo, A.; Badelek, B.; Gazda, R.; Klimaszewski, K.; Kurek, K.; Nassalski, J.; Pawlukiewicz-Kaminska, B.; Rondio, E.; Sandacz, A.; Wislicki, W.; Barth, J.; Klein, F.; Panknin, R.; Pretz, J.; Windmolders, R.; Baum, G.; Bedfer, Y.; Burtin, E.; El Alaoui, A.; Ferrero, A.; Hose, N. d'; Jegou, G.; Kunne, F.; Le Goff, J.M.; Magnon, A.; Marchand, C.; Neyret, D.; Platchkov, S.; Robinet, F.; Bernhard, J.; Chaberny, D.; Harrach, D. von; Jasinski, P.; Kabuss, E.; Koblitz, S.; Korzenev, A.; Ostrick, M.; Pochodzalla, J.; Siebert, H.W.; Bettinelli, M.; Duennweber, W.; Faessler, M.; Geyer, R.; Rajotte, J.F.; Schlueter, T.; Uman, I.; Zvyagin, A.; Birsa, R.; Bravar, A.; Dalla Torre, S.; Gobbo, B.; Tessaro, S.; Tessarotto, F.; Bisplinghoff, J.; Eversheim, P.D.; Hinterberger, F.; Jahn, R.; Joosten, R.; Massmann, F.; Negrini, T.; Bordalo, P.; Franco, C.; Nunes, A.S.; Quintans, C.; Ramos, S.; Santos, H.; Silva, L.; Bradamante, F.; Bressan, A.; Duic, V.; Giorgi, M.; Levorato, S.; Martin, A.; Pesaro, G.; Sbrizzai, G.; Schiavon, P.; Sozzi, F.; Takekawa, S.; Brona, G.; Chung, S.U.; Friedrich, J.M.; Grabmueller, S.; Grube, B.; Haas, F.; Hoeppner, C.; Ketzer, B.; Konopka, R.; Kraemer, M.; Kuhn, R.; Mann, A.; Nagel, T.; Neubert, S.; Paul, S.; Schmitt, L.; Uhl, S.; Weitzel, Q.; Cicuttin, A.; Crespo, M.L.; Diaz, V.; Das, S.; Dasgupta, S.S.; Dhara, L.; Sarkar, S.; Sinha, L.; Denisov, O.Yu.; Donskov, S.V.; Filin, A.; Khaustov, G.V.; Khokhlov, Yu.A.; Kolosov, V.N.; Konstantinov, V.F.; Lednev, A.A.; Mikhailov, Yu.V.; Nikolaenko, V.I.; Polyakov, V.A.; Ryabchikov, D.I.; Samoylenko, V.D.; Doshita, N.; Kondo, K.; Eyrich, W.; Lehmann, A.; Richter, A.; Schroeder, W.; Teufel, A.; Finger, M.; Fischer, H.; Heinsius, F.H.; Herrmann, F.; Kang, D.; Koenigsmann, K.; Lauser, L.; Nerling, F.; Schill, C.; Schopferer, S.; Vossen, A.; Wollny, H.; Gautheron, F.; Hess, C.; Kisselev, Yu.; Koivuniemi, J.H.; Meyer, W.; Reicherz, G.; Gerassimov, S.; Konorov, I.; Goertz, S.; Hasegawa, T.; Matsuda, T.; Horikawa, N.; Ishimoto, S.; Ilgner, C.; Iwata, T.; Michigami, T.; Kouznetsov, O.; CEA IRFU/SPhN Saclay, Gif-sur-Yvette; Soltan Institute for Nuclear Studies and University of Warsaw, Warsaw; Lichtenstadt, J.; Moinester, M.A.; Mallot, G.K.; Stolarski, M.; Marzec, J.; Padee, A.; Sulej, R.; Zaremba, K.; Ziembicki, M.; Mutter, A.; Panzieri, D.; Polak, J.; Srnka, A.; Sulc, M.; Zhao, J.
2010-01-01
Azimuthal asymmetries in semi-inclusive production of positive (h + ) and negative hadrons (h - ) have been measured by scattering 160 GeV muons off longitudinally polarised deuterons at CERN. The asymmetries were decomposed in several terms according to their expected modulation in the azimuthal angle φ of the outgoing hadron. Each term receives contributions from one or several spin and transverse-momentum-dependent parton distribution and fragmentation functions. The amplitudes of all φ-modulation terms of the hadron asymmetries integrated over the kinematic variables are found to be consistent with zero within statistical errors, while the constant terms are nonzero and equal for h + and h - within the statistical errors. The dependencies of the φ-modulated terms versus the Bjorken momentum fraction x, the hadron fractional momentum z, and the hadron transverse momentum p h T were studied. The x dependence of the constant terms for both positive and negative hadrons is in agreement with the longitudinal double-spin hadron asymmetries, measured in semi-inclusive deep-inelastic scattering. The x dependence of the sin φ-modulation term is less pronounced than that in the corresponding HERMES data. All other dependencies of the φ-modulation amplitudes are consistent with zero within the statistical errors. (orig.)
Electron scattering on molecular hydrogen
International Nuclear Information System (INIS)
Wingerden, B. van.
1980-01-01
The author considers scattering phenomena which occur when a beam of electrons interacts with a molecular hydrogen gas of low density. Depending on the energy loss of the scattered electrons one can distinguish elastic scattering, excitation and (auto)ionization of the H 2 -molecule. The latter processes may also lead to dissociation. These processes are investigated in four experiments in increasing detail. (Auth.)
International Nuclear Information System (INIS)
Gurchin, Yu.V.; Isupov, A.Yu.; Khrenov, A.N.; Kiselev, A.S.; Ladygin, V.P.; Reznikov, S.G.; Vasil'ev, T.A.; Janek, M.; Karachuk, J.T.
2011-01-01
A selection of dp-elastic scattering events at energies of 1.6 and 2.0 GeV by using scintillation counters has been performed. The procedure of the CH 2 -C subtraction has been established. The dependence of the elastic events yield on the filter thickness has been investigated. This method can be used to develop the efficient high-energy deuteron beam polarimetry
Precision measurements of g1 of the proton and of the deuteron with 6 GeV electrons
Prok, Y.; Bosted, P.; Kvaltine, N.; Adhikari, K. P.; Adikaram, D.; Aghasyan, M.; Amaryan, M. J.; Anderson, M. D.; Anefalos Pereira, S.; Avakian, H.; Baghdasaryan, H.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Biselli, A. S.; Bono, J.; Briscoe, W. J.; Brock, J.; Brooks, W. K.; Bültmann, S.; Burkert, V. D.; Carlin, C.; Carman, D. S.; Celentano, A.; Chandavar, S.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Cortes, O.; Crabb, D.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Dodge, G. E.; Doughty, D.; Dupre, R.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Fedotov, G.; Fegan, S.; Fersch, R.; Fleming, J. A.; Forest, T. A.; Garçon, M.; Garillon, B.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Girod, F. X.; Giovanetti, K. L.; Goetz, J. T.; Gohn, W.; Gothe, R. W.; Griffioen, K. A.; Guegan, B.; Guler, N.; Hafidi, K.; Hanretty, C.; Harrison, N.; Hattawy, M.; Hicks, K.; Ho, D.; Holtrop, M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jawalkar, S.; Jiang, X.; Jo, H. S.; Joo, K.; Kalantarians, N.; Keith, C.; Keller, D.; Khandaker, M.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Koirala, S.; Kubarovsky, V.; Kuhn, S. E.; Kuleshov, S. V.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; Mayer, M.; McKinnon, B.; Meekins, D.; Mineeva, T.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Moutarde, H.; Movsisyan, A.; Munevar, E.; Munoz Camacho, C.; Nadel-Turonski, P.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Pappalardo, L. L.; Paremuzyan, R.; Park, K.; Peng, P.; Phillips, J. J.; Pierce, J.; Pisano, S.; Pogorelko, O.; Pozdniakov, S.; Price, J. W.; Procureur, S.; Protopopescu, D.; Puckett, A. J. R.; Raue, B. A.; Rimal, D.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Saini, M. S.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Sharabian, Y. G.; Simonyan, A.; Smith, C.; Smith, G.; Sober, D. I.; Sokhan, D.; Stepanyan, S. S.; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Sytnik, V.; Taiuti, M.; Tang, W.; Tkachenko, S.; Ungaro, M.; Vernarsky, B.; Vlassov, A. V.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Weinstein, L. B.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, B.; Zhao, Z. W.; Zonta, I.; CLAS Collaboration
2014-08-01
The inclusive polarized structure functions of the proton and deuteron, g1p and g1d, were measured with high statistical precision using polarized 6 GeV electrons incident on a polarized ammonia target in Hall B at Jefferson Laboratory. Electrons scattered at laboratory angles between 18 and 45 degrees were detected using the CEBAF Large Acceptance Spectrometer (CLAS). For the usual deep inelastic region kinematics, Q2>1 GeV2 and the final-state invariant mass W >2 GeV, the ratio of polarized to unpolarized structure functions g1/F1 is found to be nearly independent of Q2 at fixed x. Significant resonant structure is apparent at values of W up to 2.3 GeV. In the framework of perturbative quantum chromodynamics, the high-W results can be used to better constrain the polarization of quarks and gluons in the nucleon, as well as high-twist contributions.
Precision measurements of g1 of the proton and the deuteron with 6 GeV electrons
Energy Technology Data Exchange (ETDEWEB)
Prok, Yelena; Bosted, Peter; Kvaltine, Nicholas; Adhikari, Krishna; Adikaram-Mudiyanselage, Dasuni; Aghasyan, Mher; Amaryan, Moskov; Anderson, Mark; Anefalos Pereira, Sergio; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Ball, Jacques; Baltzell, Nathan; Battaglieri, Marco; Biselli, Angela; Bono, Jason; Briscoe, William; Brock, Joseph; Brooks, William; Bueltmann, Stephen; Burkert, Volker; Carlin, Christopher; Carman, Daniel; Celentano, Andrea; Chandavar, Shloka; Colaneri, Luca; Cole, Philip; Contalbrigo, Marco; Cortes, Olga; Crabb, Donald; Crede, Volker; D' Angelo, Annalisa; Dashyan, Natalya; De Vita, Raffaella; De Sanctis, Enzo; Deur, Alexandre; Djalali, Chaden; Dodge, Gail; Doughty, David; Dupre, Raphael; El Alaoui, Ahmed; El Fassi, Lamiaa; Elouadrhiri, Latifa; Fedotov, Gleb; Fegan, Stuart; Fersch, Robert; Fleming, Jamie; Forest, Tony; Garcon, Michel; Gevorgyan, Nerses; Ghandilyan, Yeranuhi; Gilfoyle, Gerard; Girod-Gard, Francois-Xavier; Giovanetti, Kevin; Goetz, John; Gohn, Wesley; Gothe, Ralf; Griffioen, Keith; Guegan, Baptiste; Guler, Nevzat; Hafidi, Kawtar; Hanretty, Charles; Harrison, Nathan; Hattawy, Mohammad; Hicks, Kenneth; Ho, Dao; Holtrop, Maurik; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Jawalkar, Sucheta; Jiang, Xiaodong; Jo, Hyon-Suk; Joo, Kyungseon; Kalantarians, Narbe; Keith, Christopher; Keller, Daniel; Khandaker, Mahbubul; Kim, Andrey; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Koirala, Suman; Kubarovsky, Valery; Kuhn, Sebastian; Kuleshov, Sergey; Lenisa, Paolo; Livingston, Kenneth; Lu, Haiyun; MacGregor, Ian; Markov, Nikolai; Mayer, Michael; McKinnon, Bryan; Meekins, David; Mineeva, Taisiya; Mirazita, Marco; Mokeev, Viktor; Montgomery, Rachel; MOUTARDE, Herve; Movsisyan, Aram; Munevar Espitia, Edwin; Munoz Camacho, Carlos; Nadel-Turonski, Pawel; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria; Osipenko, Mikhail; Ostrovidov, Alexander; Pappalardo, Luciano; Paremuzyan, Rafayel; Park, K; Peng, Peng; Phillips, J J; Pierce, Joshua; Pisano, Silvia; Pogorelko, Oleg; Pozdniakov, Serguei; Price, John; Procureur, Sebastien; Protopopescu, Dan; Puckett, Andrew; Raue, Brian; Rimal, Dipak; Ripani, Marco; Rizzo, Alessandro; Rosner, Guenther; Rossi, Patrizia; Roy, Priyashree; Sabatie, Franck; Saini, Mukesh; Salgado, Carlos; Schott, Diane; Schumacher, Reinhard; Seder, Erin; Sharabian, Youri; Simonyan, Ani; Smith, Claude; Smith, Gregory; Sober, Daniel; Sokhan, Daria; Stepanyan, Stepan; Stepanyan, Samuel; Strakovski, Igor; Strauch, Steffen; Sytnik, Valeriy; Taiuti, Mauro; Tang, Wei; Tkachenko, Svyatoslav; Ungaro, Maurizio; Vernarsky, Brian; Vlasov, Alexander; Voskanyan, Hakob; Voutier, Eric; Walford, Natalie; Watts, Daniel; Weinstein, Lawrence; Zachariou, Nicholas; Zana, Lorenzo; Zhang, Jixie; Zhao, Bo; Zhao, Zhiwen; Zonta, Irene
2014-08-01
The inclusive polarized structure functions of the proton and deuteron, g1p and g1d, were measured with high statistical precision using polarized 6 GeV electrons incident on a polarized ammonia target in Hall B at Jefferson Laboratory. Electrons scattered at lab angles between 18 and 45 degrees were detected using the CEBAF Large Acceptance Spectrometer (CLAS). For the usual DIS kinematics, Q^2>1 GeV^2 and the final-state invariant mass W>2 GeV, the ratio of polarized to unpolarized structure functions g1/F1 is found to be nearly independent of Q^2 at fixed x. Significant resonant structure is apparent at values of W up to 2.3 GeV. In the framework of perturbative QCD, the high-W results can be used to better constrain the polarization of quarks and gluons in the nucleon, as well as high-twist contributions.
Deep inelastic scattering on the deuteron in the Bethe-Salpeter formalism
International Nuclear Information System (INIS)
Kaptari, L.P.; Kazakov, K.Yu.; Umnikov, A.Yu.; Khanna, F.C.
1996-01-01
The nuclear effects in the spin structure functions of the deuteron g 1 and b 2 are estimated in a fully covariant approach of the Bethe-Salpeter formalism. The construction of the relativistic wave function of the deuteron is discussed in detail. Numerical results for g 1 and b 2 are compared with nonrelativistic results and relativistic corrections are discussed [ru
Electroweak physics and electron scattering
International Nuclear Information System (INIS)
Henley, E.M.; Hwang, W.Y.P.
1988-01-01
The electroweak theory is developed and applied to electron scattering from nucleons and light nuclei. It is shown that these scatterings can be used to test the standard theory and probe structure effects. 33 refs., 5 figs
Precise Measurement of the Deuteron Elastic structure Function A(Q2)
International Nuclear Information System (INIS)
D. Abbott; A. Ahmidouch; H. Anklin; J. Arvieux; J. Bail; S. Beedoe; E. J. Beise; L. Bimbot; W. Boeglin; H. Breuer; R. Carlini; N. S. Chant; S. Danagoulian; K. Dow; J.E. Ducret; J. Dunne; R. Ent; L. Ewell; L. Eyraud; C. Furget; M. Garcon; R. Gilman; C. Glashausser; P. Gucye; K. Gustafsson; K. Hafidi; A. Honegger; J. Jourdan; S. Kox; G. Kumbartzki; L. Lu; A. Lung; D. Mack; P. Markowitz; J. McIntyre; D. Meekins; F. Merchez; J. Mitchell; R. Mohring; S. Mtingwa; H. Mrktchyan; D. Pitz; L. Qin; R. Ransome; J.S. Real; P. G. Roos; P. Rutt; R. Sawafta; S. Stepanyan; R. Tieulent; E. Tomasi-Gustafsson; W. Turchinetz; K. Vansyoc; J. Volmer; E. Voutier; W. Vulcan; C. Williamson; S. A. Wood; C. Yan; J. Zhao; W. Zhao
1999-01-01
The A(Q 2 ) structure function in elastic electron-deuteron scattering was measured at six momentum transfers Q 2 between 0.66 and 1.80 (GeV/c) 2 in Hall C at Jefferson Laboratory. The scattered electrons and recoil deuterons were detected in coincidence, at a fixed deuteron angle of 60.5 o . These new precise measurements resolve discrepancies between older sets of data. They put significant constraints on existing models of the deuteron electromagnetic structure, and on the strength of isoscalar meson exchange currents
Precise Measurement of the Deuteron Elastic Structure Function A(Q2 )
International Nuclear Information System (INIS)
Ball, J.; Ducret, J.; Garcon, M.; Hafidi, K.; Pitz, D.; Tomasi-Gustafsson, E.; Honegger, A.; Jourdan, J.; Zhao, J.; Beise, E.J.; Breuer, H.; Chant, N.S.; Ewell, L.; Gustafsson, K.; Lung, A.; Mohring, R.; Pitz, D.; Roos, P.G.; Eyraud, L.; Furget, C.; Kox, S.; Lu, L.; Merchez, F.; Real, J.; Tieulent, R.; Voutier, E.; Abbott, D.; Carlini, R.; Dunne, J.; Ent, R.; Gilman, R.; Gueye, P.; Mack, D.; Meekins, D.; Mitchell, J.; Pitz, D.; Qin, L.; Vansyoc, K.; Volmer, J.; Vulcan, W.; Wood, S.A.; Yan, C.; Gilman, R.; Glashausser, C.; Kumbartzki, G.; McIntyre, J.; Ransome, R.; Rutt, P.; Ahmidouch, A.; Dow, K.; Turchinetz, W.; Williamson, C.; Zhao, W.; Anklin, H.; Boeglin, W.; Markowitz, P.; Mrktchyan, H.; Stepanyan, S.; Ahmidouch, A.; Beedoe, S.; Danagoulian, S.; Mtingwa, S.; Sawafta, R.; Arvieux, J.; Ball, J.; Tomasi-Gustafsson, E.; Arvieux, J.; Bimbot, L.
1999-01-01
The A(Q 2 ) structure function in elastic electron-deuteron scattering was measured at six momentum transfers Q 2 between 0.66 and 1.80 (GeV/c) 2 in Hall C at Jefferson Laboratory. The scattered electrons and recoil deuterons were detected in coincidence, at a fixed deuteron angle of 60.5 degree. These new precise measurements resolve discrepancies between older sets of data. They put significant constraints on existing models of the deuteron electromagnetic structure, and on the strength of isoscalar meson exchange currents. copyright 1999 The American Physical Society
International Nuclear Information System (INIS)
Gruebler, W.; Koenig, V.; Schmelzbach, P.A.; Stammbach, T.
A double scatter experiment is proposed in which the tensor polarization of the recoil deuterons is measured in the forwards direction. It is noted that using a relatively simple measurement arrangement and a short measurement time, the D-state admixture in deuterons can be determined very precisely. The experimental facilities and arrangments, structural predictions, estimate of collision rates and measurement time, background, possible improvements, and the equipment and financing are discussed. 3 references
Electron scattering for exotic nuclei
International Nuclear Information System (INIS)
Suda, T.
2013-01-01
An electron scattering facility is under construction in RIKEN RI Beam Factory, Japan, which is dedicated to the structure studies of short-lived nuclei. This is the world's first and currently only facility of its type. The construction is nearly completed, and the first electron scattering experiment off short-lived nuclei will be carried out in the beginning of next year. The charge density distributions of short-lived nuclei will be precisely determined by elastic electron scattering for the first time. Physics pursued at this facility including future perspectives are explained
Electron scattering for exotic nuclei
Indian Academy of Sciences (India)
2014-11-04
Nov 4, 2014 ... Research Center for Electron-Photon Science, Tohoku University, 1-2-1 ... nuclei precisely determined by elastic scattering [1]. .... In order to fulfill these requirements, a window-frame shaped dipole magnet with a gap.
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.)
On the meson exchange currents contribution in deep inelastic scattering on deuteron
International Nuclear Information System (INIS)
Kaptar', L.P.; Titov, A.I.; Umnikov, A.Yu.
1988-01-01
The contribution of the one- and two-pion exchange currents to the deep inelastic deuteron structure function F 2 D (x) is considered. It is shown that the mesonic corrections do not restore the energy sum rule violated by the off-mass-shell properties of the bound nucleons
[Inelastic electron scattering from surfaces
International Nuclear Information System (INIS)
1993-01-01
This program uses ab-initio and multiple scattering to study surface dynamical processes; high-resolution electron-energy loss spectroscopy is used in particular. Off-specular excitation cross sections are much larger if electron energies are in the LEED range (50--300 eV). The analyses have been extended to surfaces of ordered alloys. Phonon eigenvectors and eigenfrequencies were used as inputs to electron-energy-loss multiple scattering cross section calculations. Work on low-energy electron and positron holography is mentioned
Measurements of T20 in backward elastic d p scattering at deuteron momenta 3.5 - 6 GeV/c
International Nuclear Information System (INIS)
Azhgirej, L.S.; Borzunov, Yu.T.; Chernykh, E.V.
1994-01-01
We present results of measurements of the tensor analyzing power T 20 in d p backward elastic scattering at initial deuterons momenta 3.5-6.0 GeV/c, which corresponds to the range of internal momentum of the deuteron constituents k = 0.5 - 0.8 GeV/c. New structure was observed at k = 0.65 GeV/c. Difference between behavior of T 20 for d p backward elastic scattering and for breakup reaction, which have a smooth behavior of T 20 at high k, is discussed. 12 refs.; 3 figs. (author)
Electron scattering violates parity
2004-01-01
Parity violation has been observed in collisions between electrons at the Stanford Linear Accelerator Center (SLAC) in the US. The resuls, which are in agreement with the Stanford Model of particle physics, also provide a new measurement of the weak charge of the electron (½ page)
Electron scattering by hydrogen atoms
International Nuclear Information System (INIS)
Fujii, D.H.
1981-02-01
A variational method to calculate the differential cross section of the electron-hydrogen atom scattering process is presented. The second Born approximation is calculated, through a variational calculation using the energy and electronic charge simultaneously as parameters, in order to calculate the differential cross section which is written in a fractional form according to the Schwinger variational principle. Effects due to the electron change are included in the calculations. (L.C.) [pt
Adams, D; Adeva, B; Akdogan, T; Arik, E; Arvidson, A; Badelek, B; Ballintijn, M K; Bardin, Dimitri Yuri; Bardin, G; Baum, G; Berglund, P; Betev, L; Bird, I G; Birsa, R; Björkholm, P; Bonner, B E; De Botton, N R; Boutemeur, M; Bradamante, Franco; Bravar, A; Bressan, A; Bültmann, S; Burtin, E; Cavata, C; Crabb, D; Cranshaw, J; Çuhadar-Dönszelmann, T; Dalla Torre, S; Van Dantzig, R; Derro, B R; Deshpande, A A; Dhawan, S K; Dulya, C M; Dyring, A; Eichblatt, S; Faivre, Jean-Claude; Fasching, D; Feinstein, F; Fernández, C; Frois, Bernard; Gallas, A; Garzón, J A; Gaussiran, T; Giorgi, M A; von Goeler, E; Gómez, F; Gracia, G; De Groot, N; Grosse-Perdekamp, M; Von Harrach, D; Hasegawa, T; Hautle, P; Hayashi, N; Heusch, C A; Horikawa, N; Hughes, V W; Igo, G; Ishimoto, S; Iwata, T; Kabuss, E M; Kageya, T; Kalinovskaya, L V; Karev, A G; Kessler, H J; Ketel, T; Kiryluk, J; Kishi, A; Kiselev, Yu F; Klostermann, L; Krämer, Dietrich; Krivokhizhin, V G; Kröger, W; Kukhtin, V V; Kurek, K; Kyynäräinen, J; Lamanna, M; Landgraf, U; Le Goff, J M; Lehár, F; de Lesquen, A; Lichtenstadt, J; Lindqvist, T; Litmaath, M; Loewe, M; Magnon, A; Mallot, G K; Marie, F; Martin, A; Martino, J; Matsuda, T; Mayes, B W; McCarthy, J S; Medved, K S; Van Middelkoop, G; Miller, D; Mori, K; Moromisato, J H; Nagaitsev, A P; Nassalski, J P; Naumann, Lutz; Niinikoski, T O; Oberski, J; Ogawa, A; Ozben, C; Parks, D P; Perrot-Kunne, F; Peshekhonov, V D; Piegaia, R; Pinsky, L; Platchkov, S K; Pló, M; Polec, J; Pose, D; Postma, H; Pretz, J; Puntaferro, R; Pussieux, T; Pyrlik, J; Rädel, G; Rijllart, A; Roberts, J B; Rock, S E; Rodríguez, M; Rondio, Ewa; Rosado, A; Sabo, I; Saborido, J; Sandacz, A; Savin, I A; Schiavon, R P; Schüler, K P; Seitz, R; Semertzidis, Y K; Sever, F; Shanahan, P; Sichtermann, E P; Simeoni, F; Smirnov, G I; Staude, A; Steinmetz, A; Steigler, U; Stuhrmann, H B; Szleper, M; Teichert, K M; Tessarotto, F; Tlaczala, W; Trentalange, S; Tripet, A; Ünel, G; Velasco, M; Vogt, J; Voss, Rüdiger; Weinstein, R; Whitten, C; Windmolders, R; Willumeit, R; Wislicki, W; Witzmann, A; Yañez, A; Ylöstalo, J; Zanetti, A M; Zaremba, K; Zhao, J
1997-01-01
We present a new measurement of the spin-dependent structure function $g_{1}^{\\rm d}$ of the deuteron from deep inelastic scattering of 190 GeV polarized muons on polarized deuterons. The results are combined with our previous measurements of $g_{1}^{\\rm d}$. A perturbative QCD evolution in next-to-leading order is used to compute $g_{1}^{\\rm d}(x)$ at a constant $Q^{2}$. At $Q^{2} = 10$ GeV$^{2}$, we obtain a first moment $\\Gamma_{1}^{\\rm d} = \\int_{0}^{1} g_{1}^{\\rm d}{\\rm d}x = 0.041 \\pm 0.008$, a flavour-singlet axial charge of the nucleon $a_{0} = 0.30 \\pm 0.08$, and an axial charge of the strange quark $a_{s} = -0.09 \\pm 0.03$. Using our earlier determination of $\\Gamma_{1}^{\\rm p}$, we obtain $\\Gamma_1^{\\rm p} - \\Gamma_1^{\\rm n} = 0.183 \\pm 0.035$ at $Q^2 = 10\\,\\mbox{GeV}^2$. This result is in agreement with the Bjorken sum rule which predicts $\\Gamma_1^{\\rm p} - \\Gamma_1^{\\rm n} = 0.186 \\pm 0.002$ at the same $Q^2$.
Wavepacket electron scattering
International Nuclear Information System (INIS)
Marks, L.D.
1986-01-01
In this note, the formal analysis of the electron wavepacket produced by a STEM instrument is sketched, and some of the diffraction effects briefly described. It is hoped that this will encourage some needed analysis of the complicated inelastic processes occurring in this experimental geometry. 21 references, 3 figures
Particle interaction with the deuteron
International Nuclear Information System (INIS)
Rosa, L.P.
1974-09-01
A study of the particle deuteron interactions at low, intermediate and high energies is presented. The differential cross section for pion deuteron scattering, near the 33 resonance, is calculated considering the Fermi motion and the off energy shell effects. We present formulae for the calculation of correction to the incoherent production cross section on deuteron arising from the multiple scattering and interference; we apply them to the case K + → K 0 π + between 1. and 5 Gev/c. is introduced. A relativistic correction to the double scattering Glauber formula and is done an application to the rho photoproduction on deuteron at high energies
Electron scattering off palladium isotopes
International Nuclear Information System (INIS)
Laan, J.B. van der.
1986-01-01
The low-lying states of the even Pd isotopes are characterized by vibrator-like properties. In this thesis the results of an electron scattering experiment on the Pd isotopes, designed to study the description of such nuclei in the Anharmonic Vibrator Model (AVM) and the Interacting Boson Approximation (IBA), are presented and discussed. Data have been taken at the high-resolution electron scattering facility of NIKHEF-K and covered a momentum-transfer range of 0.4 to 2.5 fm -1 . (Auth.)
Electron scattering by molecular oxygen
International Nuclear Information System (INIS)
Duddy, P.E.
1999-03-01
Collisions of electrons with molecules is one of the fundamental processes which occur both in atomic and molecular physics and also in chemistry. These collisions are vital in determining the energy balance and transport properties of electrons in gases and plasmas at low temperatures. There are many important applications for the basic understanding of these collision processes. For example, the study of planetary atmospheres and the interstellar medium involves electron collisions with both molecules and molecular ions. In particular, two of the major cooling mechanisms of electrons in the Earth's ionosphere are (i) the fine structure changing transitions of oxygen atoms by electron impact and (ii) the resonant electron-impact vibrational excitation of N 2 . Other applications include magnetohydrodynamic power generation and laser physics. A molecule, by definition, will contain more than one nucleus and consequently the effect of nuclear motion in the molecule leads to many extra processes in electron scattering by molecules which cannot occur in electron-atom scattering. As for atoms, both elastic and inelastic scattering occur, but in the case of inelastic electron scattering by molecules, the target molecule is excited to a different state by the process. The excitation may be one, or some combination, of rotational, vibrational and electronic transitions. Other reactions which may occur include dissociation of the molecule into its constituent atoms or ionisation. Another difficulty arises when considering the interactions between the electron and the molecule, This interaction, which considerably complicates the calculation, is non-spherical and various methods have been developed over the years to represent this interaction. This thesis considers electron scattering by molecular oxygen in the low energy range i.e. 0-15eV. These collisions are of considerable interest in atmospheric physics and chemistry where the electron impact excitation of O 2 has
Giant quadrupole resonance in 12C, 24Mg, and 27Al observed via deuteron inelastic scattering
International Nuclear Information System (INIS)
Chang, C.C.; Didelez, J.P.; Kwiatowski, K.; Wo, J.R.
1977-06-01
Giant quadrupole resonance in 12 C, 24 Mg, and 27 Al was studied using 70 MeV deuteron beam. The results clearly show, in all three targets, resonance-like structures peaked at E/sub x/ approximately 63A/sup -1/3/ MeV, with a width of about 10 MeV. The experimental angular distributions for these resonances agree well with the l = 2 DWBA prediction. For 12 C, a binary splitting was observed, and for 24 Mg, there are indications of finer structure in the main giant quadrupole resonance region
International Nuclear Information System (INIS)
Witala, H.; Hueber, D.; Gloeckle, W.; Tornow, W.; Gonzalez Trotter, D.E.
1996-01-01
Data for the neutron-neutron final-state-interaction cross section obtained recently in a kinematically complete neutron-deuteron breakup experiment have been reanalyzed using rigorous solutions of the three-nucleon Faddeev equations with realistic nucleon-nucleon interactions. A discrepancy was found with respect to a recent analysis based on the W-matrix approximation to the Paris potential. We also estimate theoretical uncertainties in extracting the neutron-neutron scattering length resulting from the use of different nucleon-nucleon interactions and the possible action of the two pion-exchange three-nucleon force. We find that there exists a certain production angle for the interacting neutron-neutron pair where the uncertainties become minimal. (author)
Transition densities with electron scattering
International Nuclear Information System (INIS)
Heisenberg, J.
1985-01-01
This paper reviews the ground state and transition charge densities in nuclei via electron scattering. Using electrons as a spectroscopic tool in nuclear physics, these transition densities can be determined with high precision, also in the nuclear interior. These densities generally ask for a microscopic interpretation in terms of contributions from individual nucleons. The results for single particle transitions confirm the picture of particle-phonon coupling. (Auth.)
Deuteron form factor measurements at low momentum transfers
Directory of Open Access Journals (Sweden)
Schlimme B. S.
2016-01-01
Full Text Available A precise measurement of the elastic electron-deuteron scattering cross section at four-momentum transfers of 0.24 fm−1 ≤ Q ≤ 2.7 fm−1 has been performed at the Mainz Microtron. In this paper we describe the utilized experimental setup and the necessary analysis procedure to precisely determine the deuteron charge form factor from these data. Finally, the deuteron charge radius rd can be extracted from an extrapolation of that form factor to Q2 = 0.
Nuclear matter and electron scattering
Energy Technology Data Exchange (ETDEWEB)
Sick, I [Dept. fuer Physik und Astronomie, Univ. Basel (Switzerland)
1998-06-01
We show that inclusive electron scattering at large momentum transfer allows a measurement of short-range properties of nuclear matter. This provides a very valuable constraint in selecting the calculations appropriate for predicting nuclear matter properties at the densities of astrophysical interest. (orig.)
Deuteron microscopic optical model potential
International Nuclear Information System (INIS)
Guo Hairui; Han Yinlu; Shen Qingbiao; Xu Yongli
2010-01-01
A deuteron microscopic optical model potential is obtained by the Green function method through nuclear-matter approximation and local-density approximation based on the effective Skyrme interaction. The microscopic optical model potential is used to calculate the deuteron reaction cross sections and the elastic scattering angular distributions for some target nuclei in the mass range 6≤A≤208 with incident deuteron energies up to 200 MeV. The calculated results are compared with the experimental data.
International Nuclear Information System (INIS)
Rekalo, M.P.; Tomasi-Gustafsson, E.
1996-01-01
The microscopic structure of the nucleon N and its excited states N* can be determined through the (elastic or inelastic) electromagnetic form factors. These form factors should help to understand the nature of the transition regime from soft physics of the confinement region to the hard physics of the perturbative QCD. The authors show that hadron induced reactions with isospin zero projectiles, could be an effective method for the study of the nucleon structure, in particular through the measurement of polarization observables. They analyzed the properties of the inclusive d + p reactions, with particular interest in the domain of nucleonic resonances excitation. The calculated cross section and polarization observables show that it is possible to disentangle the different reaction mechanisms (omega, sigma and eta exchange) and bring new information about the electromagnetic form factors of the deuteron as well as of the nucleonic resonances. Existing data on the tensor analyzing power are in agreement with the prediction based on the omega exchange model. (authors)
Electron scattering and nuclear structure
International Nuclear Information System (INIS)
Frois, B.
1987-01-01
The search for the appropriate degrees of freedom to describe nuclei is the central focus of nuclear physics today. Therefore the authors explore in this review their current understanding of nuclear structure as defined by electromagnetic data. The precision of the electromagnetic probe allows us to define accurately the limits of present theoretical descriptions. The authors review here a broad range of subjects that have been addressed by recent experiments, from the study of meson exchange currents and single-particle distributions to collective excitations in heavy nuclei. However, they do not discuss elastic magnetic scattering, inelastic excitation of discrete states, or single-nucleon knockout reactions since these reactions were recently reviewed. The principal aim of this review is to offer a fresh perspective on nuclear structure, based on the new generation of electron scattering data presented here and in the above-mentioned articles
Czech Academy of Sciences Publication Activity Database
Alekseev, M.; Alexakhin, V. Yu.; Alexandrov, Yu.; Alexeev, G. D.; Amoroso, A.; Austregisilio, A.; Badelek, B.; Balestra, F.; Barth, J.; Baum, G.; Bedfer, Y.; Bernhard, J.; Bertini, R.; Bettinelli, M.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, F.; Bravar, A.; Bressan, A.; Brona, G.; Burtin, E.; Bussa, M.; Chaberny, D.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Colantoni, M.; Crespo, M.; Dalla Torre, S.; Das, S.; Dasgupta, S. S.; Denisov, O.; Dhara, L.; Diaz, V.; Donskov, S.; Doshita, N.; Duic, V.; Dünnweber, W.; Efremov, A.V.; El Alaoui, A.; Eversheim, P.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Finger jr., M.; Fischer, H.; Franco, C.; Friedrich, J.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.; Gazda, R.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Grabmüller, S.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Haas, F.; von Harrach, D.; Hasegawa, T.; Heinsius, F.; Herrmann, F.; Hess, C.; Hinterberger, F.; Horikawa, N.; Höppner, Ch.; d'Hose, N.; Ilgner, C.; Ishimoto, S.; Ivanov, O.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jasinski, P.; Jegou, G.; Joosten, R.; Jouravlev, N. I.; Kabuss, E.; Kang, D.; Ketzer, B.; Khaustov, G.; Khokhlov, Y.; Kisselev, Y.; Klein, F.; Klimaszewski, K.; Koblitz, S.; Koivuniemi, J.; Kolosov, V.; Kondo, K.; Königsmann, K.; Konopka, R.; Konorov, I.; Konstantinov, V.; Korzenev, A.; Kotzinian, A.; Kouznetsov, O.; Kowalik, K.; Krämer, M.; Kral, A.; Kroumchtein, Z.; Kuhn, R.; Kunne, F.; Kurek, K.; Lauser, L.; Le Goff, J.; Lednev, A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Liska, T.; Maggiora, A.; Maggiora, M.; Magnon, A.; Mallot, G.; Mann, A.; Marchand, C.; Martin, A.; Marzec, J.; Massmann, F.; Matsuda, T.; Meyer, W.; Michigami, T.; Mikhailov, Y.; Moinester, M.; Mutter, A.; Nagaytsev, A.; Nagel, T.; Nassalski, J.; Negrini, S.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.; Nunes, A.S.; Olshevsky, A.; Ostrick, M.; Padee, A.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Pawlukiewicz-Kaminska, B.; Perevalova, E.; Pesaro, G.; Peshekhonov, D.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.; Pontecorvo, G.; Pretz, J.; Quintans, C.; Rajotte, J.; Ramos, S.; Rapatsky, V.; Reicherz, G.; Richter, A.; Robinet, F.; Rocco, E.; Rondio, E.; Ryabchikov, D.; Samoylenko, V.; Sandacz, A.; Santos, H.; Sapozhnikov, M.; Sarkar, S.; Savin, I.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schlütter, T.; Schmitt, L.; Schopferer, S.; Schröder, W.; Shevchenko, O.; Siebert, H.; Silva, L.; Sinha, L.; Sissakian, A.; Slunecka, M.; Smirnov, G.; Sosio, S.; Sozzi, F.; Srnka, Aleš; Stolarski, M.; Sulc, M.; Sulej, R.; Takekawa, S.; Tessaro, S.; Tessarotto, F.; Teufel, A.; Tkatchev, L.; Uhl, S.; Uman, I.; Virius, M.; Vlassov, N.; Vossen, A.; Weitzel, Q.; Windmolders, R.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zhao, J.; Zhuravlev, N.; Zvyagin, A.
2010-01-01
Roč. 70, 1-2 (2010), s. 39-49 ISSN 1434-6044 R&D Projects: GA MŠk ME 492 Institutional research plan: CEZ:AV0Z20650511 Keywords : deep-inelastic-scattering * dependent structure-function * single-spin asymmetries * semiinclusive electroproduction * proton-scattering * distributions * leptoproduction * target * dis * nucleons Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 3.248, year: 2010
High-intensity-laser-electron scattering
International Nuclear Information System (INIS)
Meyerhofer, D.D.
1997-01-01
In the field of an intense laser, photon-electron scattering becomes nonlinear when the oscillatory energy of the electron approaches its rest mass. The electron wave function is dressed by the field with a concomitant increase in the effective electron mass. When the photon energy in the electron rest frame is comparable to the electron rest mass, multiphoton Compton scattering occurs. When the photon energy is significantly lower than the electron rest mass, the electron acquires momentum from the photon field and emits harmonics. This paper reviews nonlinear photon-electron scattering processes and results from two recent experiments where they have been observed
Photons emission processes in electron scattering
International Nuclear Information System (INIS)
Soto Vargas, C.W.
1996-01-01
The investigations involving the scattering sections arising in virtual an real photon emission processes of electron and positron scattering by an atomic nucleus, have the need for thorough and complete calculations of the virtual photon spectrum and then introduce the distorted wave formulation, which is mathematically involved an numerically elaborated, but accessible to its use in experimental electron scattering facilities. (author) [es
Correlations among observables in the neutron-deuteron elastic scattering at low energies
International Nuclear Information System (INIS)
Frederico, T.; Goldman, I.D.
1984-01-01
The 2 S amplitude of the n-d elastic scattering appears like function of the dublet ( 2 a) scattering length in the three nucleons calculations. The correlation of Kcotg 2 δ o with 2 a, with separable N-N potential calculations, is obtained and the result is independent of the N-N potential. The 2 δ o (n-d) values obtained with these lines, using 2 a=.65F (experimental value), agree with p-d data. 2 S and 4 S scattering amplitude and tritium energy (E T ) calculations are performed with the zero-range model and an alternative deduction is proposed. These results for the E T and Kcotg 2 δ o correlation with 2 a show the limitations of this model. (L.C.) [pt
Pion-deuteron scattering in the range of the Delta resonance
International Nuclear Information System (INIS)
Conrads, A.
1988-10-01
The author calculates the observables for elastic πd scattering at intermediate energies in the framework of a model which is based on an effective meson field theory, whereby also the Δ isobar is regarded. The calculation is reduced to the determination of the four two-body T matrices for the processes NN→NN, NN→NΔ, and NΔ→NΔ in the framework of a Tamm-Dancoff approximation. After a calculation of the p-wave πN scattering phase shift results are presented on differential cross sections and polarization asymmetries in the energy range from 116 MeV to 292 MeV. (HSI)
Czech Academy of Sciences Publication Activity Database
Alekseev, M.; Alexakhin, V. Yu.; Alexandrov, Yu.; Alexeev, G. D.; Amoroso, A.; Austregisilio, A.; Badelek, B.; Balestra, F.; Barth, J.; Baum, G.; Bedfer, Y.; Bernhard, J.; Bertini, R.; Bettinelli, M.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, F.; Bravar, A.; Bressan, A.; Brona, G.; Burtin, E.; Bussa, M.; Chaberny, D.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Colantoni, M.; Crespo, M.; Dalla Torre, S.; Das, S.; Dasgupta, S. S.; Denisov, O.; Dhara, L.; Diaz, V.; Donskov, S.; Doshita, N.; Duic, V.; Dünnweber, W.; Efremov, A.V.; El Alaoui, A.; Eversheim, P.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Finger jr., M.; Fischer, H.; Franco, C.; Friedrich, J.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.; Gazda, R.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Grabmüller, S.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Haas, F.; von Harrach, D.; Hasegawa, T.; Heinsius, F.; Herrmann, F.; Hess, C.; Hinterberger, F.; Horikawa, N.; Höppner, Ch.; d'Hose, N.; Ilgner, C.; Ishimoto, S.; Ivanov, O.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jasinski, P.; Jegou, G.; Joosten, R.; Kabuss, E.; Kang, D.; Ketzer, B.; Khaustov, G.; Khokhlov, Y.; Kisselev, Y.; Klein, F.; Klimaszewski, K.; Koblitz, S.; Koivuniemi, J.; Kolosov, V.; Kondo, K.; Königsmann, K.; Konopka, R.; Konorov, I.; Konstantinov, V.; Korzenev, A.; Kotzinian, A.; Kouznetsov, O.; Kowalik, K.; Krämer, M.; Kral, A.; Kroumchtein, Z.; Kuhn, R.; Kunne, F.; Kurek, K.; Lauser, L.; Le Goff, J.; Lednev, A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Liska, T.; Maggiora, A.; Maggiora, M.; Magnon, A.; Makke, N.; Mallot, G.; Mann, A.; Marchand, C.; Martin, A.; Marzec, J.; Massmann, F.; Matsuda, T.; Meyer, W.; Michigami, T.; Mikhailov, Y.; Moinester, M.; Mutter, A.; Nagaytsev, A.; Nagel, T.; Nassalski, J.; Negrini, S.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.; Nunes, A.S.; Olshevsky, A.; Ostrick, M.; Padee, A.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Pawlukiewicz-Kaminska, B.; Perevalova, E.; Pesaro, G.; Peshekhonov, D.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.; Pontecorvo, G.; Pretz, J.; Quintans, C.; Rajotte, J.; Ramos, S.; Rapatsky, V.; Reicherz, G.; Richter, A.; Robinet, F.; Rocco, E.; Rondio, E.; Ryabchikov, D.; Samoylenko, V.; Sandacz, A.; Santos, H.; Sapozhnikov, M.; Sarkar, S.; Savin, I.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schlütter, T.; Schmitt, L.; Schopferer, S.; Schröder, W.; Shevchenko, O.; Siebert, H.; Silva, L.; Sinha, L.; Sissakian, A.; Slunecka, M.; Smirnov, G.; Sosio, S.; Sozzi, F.; Srnka, Aleš; Stolarski, M.; Sulc, M.; Sulej, R.; Takekawa, S.; Tessaro, S.; Tessarotto, F.; Teufel, A.; Tkatchev, L.; Uhl, S.; Uman, I.; Virius, M.; Vlassov, N.; Vossen, A.; Weitzel, Q.; Windmolders, R.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zhao, J.; Zhuravlev, N.; Zvyagin, A.
2010-01-01
Roč. 693, č. 3 (2010), s. 227-235 ISSN 0370-2693 R&D Projects: GA MŠk ME 492 Institutional research plan: CEZ:AV0Z20650511 Keywords : semi-inclusive deep inelastic scattering * structure function * parton distribution functions Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 5.255, year: 2010
International Nuclear Information System (INIS)
Korovin, P.P.; Malinina, L.V.; Strokovskij, E.A.
1998-01-01
We suggest a new dimensionless relativistic invariant variable R Δm X / ν which may be interpreted as the ratio of the excitation energy to the full transferred energy; therefore this variable measures a 'degree of inelasticity' of the scattering. Existing data on the tensor analyzing power of the p(d polarized, d ' )X and 12 C(d polarized, d ' )X inelastic scattering at momenta from 4.2 to 9 GeV/c are analyzed in terms of this variable. We observe that A yy taken as a function of R does not depend upon the incident energy, the scattering angle (up to the angles of θ cm ∼ 30 deg), and there is no noticeable difference between the proton and nuclear targets as well. It is remarkable that A yy is maximal (of ∼ 0.5) when R ∼ 0.5 - 0.6 and is small in absolute value when R is close to its limiting values of 0 and 1
Bremsstrahlung in electron-positronium scattering
International Nuclear Information System (INIS)
Amusia, M.Ya.; Korol, A.V.; Solovyov, A.V.
1986-01-01
The spectrum of radiation formed in the fast nonrelativistic electron scattering on positronium is calculated. It is shown that all the radiation proceeds via virtual positronium deformations during the collision. An essential difference of bremsstrahlung spectra in electron on positronium and electron on hydrogen scattering is demonstrated. (orig.)
[Inelastic electron scattering from surfaces
International Nuclear Information System (INIS)
1993-01-01
This program is aimed at the quantitative study of surface dynamical processes (vibrational, magnetic excitations) in crystalline slabs, ultrathin-layered materials, and chemisorbed systems on substrates, and of the geometric structure connected to these dynamical excitations. High-resolution electron-energy loss spectroscopy (HREELS) is a powerful probe. Off-specular excitation cross sections are much larger if electron energies are in the LEED range (50-300 eV). The analyses has been used to study surfaces of ordered alloys (NiAl). Ab-initio surface lattice dynamical results were combined with phonon-loss cross sections to achieve a more accurate microscopic description. First-principles phonon eigenvectors and eigenfrequencies were used as inputs to electron-energy-loss multiple scattering cross-section calculations. The combined microscopic approach was used to analyze EELS data of Cu(0001) and Ag(001) at two points. Positron diffraction is discussed as a structural and imaging tool. The relation between geometric structure of a film and its local magnetic properties will be studied in the future, along with other things
International Nuclear Information System (INIS)
Kim, J.C.; Hicks, R.S.; Yen, R.; Auer, I.P.; Caplan, H.S.; Bergstrom, J.C.
1978-01-01
Cross sections for elastic and inelastic scattering of electrons from 17 O have been measured for momentum transfers up to 1.2 fm -1 . The elastic cross section indicates that the rms charge radii of 17 O and 16 O are equal to within a few parts in a thousand: 2 17 >sup(1/2)/ 2 16 >sub(1/2)=1.0015+-0.0025. Reduced transition probabilities and ground-state radiative widths are deduced for 17 O excited states below 9 MeV. Various aspects of the inelastic spectrum are discussed, with emphasis on the 'single-particle' levels at 0.871 (1/2 + ) and 5.083 (3/2 + ) MeV, the levels at 7.569 (7/2 - ) and 7.378 (5/2 + ) MeV, and the spectrum of electric octupole excitations. (Auth.)
Energy Technology Data Exchange (ETDEWEB)
Anon.
1992-05-15
At the end of January, the 12 GeV Proton Synchrotron (PS) at the Japanese KEK Laboratory successfully accelerated deuterons to 11.2 GeV (5.6 GeV/nucleon), the limiting energy for deuterons with this ring. Beam intensity in this test exceeded 3 x 10{sup 11} particles per pulse.
Parity violating asymmetries in polarized electron scattering
International Nuclear Information System (INIS)
Derman, E.; Marciano, W.J.
1979-01-01
We discuss parity violating asymmetries between the scattering of right and left-handed electrons on a variety of targets. Implications for gauge theories from recent SLAC results on deep-inelastic electron-deuterium and electron-proton scattering are examined. A derivation of the asymmetry for electron-electron scattering is given, its advantages are pointed out, and the feasibility of such a measurement is discussed. Other proposed or contemplated asymmetry experiments are reviewed and the necessity of including the Collins-Wilczek-Zee hadronic axial isoscalar current contribution in asymmetry predictions is noted
New approach to a global description of the deuteron electromagnetic structure
International Nuclear Information System (INIS)
Dubnickova, A.Z.; Dubnicka, S.
1991-07-01
A new approach to a global description of the deuteron electro-magnetic (EM) structure is developed on the bases of a modification of the well known vector-meson-dominance (VMD) model of EM hadron interactions by incorporating the true deuteron form factor (FF) analytic properties, non-zero vector meson widths and the correct power asymptotic behaviour as predicted by QCD. As a result, the experimental data on elastic electron-deuteron scattering structure functions A(t) and B(t) are described quite well, the deuteron EM FF's in the space-like region are reproduced and their behaviour in the time- like region is predicted. At the same time the couplings of the ω-mesons to deuteron are evaluated and the total cross section of e + e - → dd-bar process is determined for the first time. (author). 47 refs, 5 figs
Parity violation in electron scattering
International Nuclear Information System (INIS)
Lhuillier, D.
2007-09-01
The elaboration of the electroweak standard model from the discovery of parity violation to the weak neutral current is described in the first chapter. In the second chapter the author discusses the 2 experimental approaches of the parity violation experiments. In the first approach the weak neutral current can be assumed to be well known and can be used as a probe for the hadronic matter. The second approach consists in measuring the weak neutral current between 2 particles with known internal structure in order to test the predictions of the standard model in the low energy range. The chapters 3 and 4 are an illustration of the first approach through the HAPPEx series of experiments that took place in the Jefferson Laboratory from 1998 to 2005. The HAPPEx experiments aimed at measuring the contribution of strange quarks in the electromagnetic form factors of the nucleon through the violation of parity in the elastic scattering at forward angles. The last chapter is dedicated to the E158 experiment that was performed at the Slac (California) between 2000 and 2003. The weak neutral current was measured between 2 electrons and the high accuracy obtained allowed the physics beyond the standard model to be indirectly constraint up to a few TeV. (A.C.)
International Nuclear Information System (INIS)
Azhgirej, L.S.; Afanas'ev, S.V.; Isupov, A.Yu.
2004-01-01
Tensor A yy and vector A y analyzing powers in the inelastic scattering of deuterons with a momentum of 5.0 GeV/c on beryllium at an angle of 178 mrad in the vicinity of the excitation of baryonic resonances with masses up to ∼ 1.8 GeV/c 2 have been measured. The A yy data are in good agreement with the previous data obtained at 4.5 and 5.5 GeV/c. The results of the experiment are compared with the predictions of the plane-wave impulse approximation and ω-meson exchange model
AUTHOR|(CDS)2067425; Arvidson, A; Badelek, B; Baum, G; Berglund, P; Betev, L; De Botton, N R; Bradamante, Franco; Bravar, A; Bültmann, S; Burtin, E; Crabb, D; Cranshaw, J; Çuhadar-Dönszelmann, T; Dalla Torre, S; Van Dantzig, R; Derro, B R; Deshpande, A A; Dhawan, S K; Dulya, C M; Eichblatt, S; Fasching, D; Feinstein, F; Fernández, C; Frois, Bernard; Gallas, A; Garzón, J A; Gilly, H; Giorgi, M A; von Goeler, E; Görtz, S; Gracia, G; De Groot, N; Grosse-Perdekamp, M; Haft, K; Von Harrach, D; Hasegawa, T; Hautle, P; Hayashi, N; Heusch, C A; Horikawa, N; Hughes, V W; Igo, G; Ishimoto, S; Iwata, T; Kabuss, E M; Karev, A G; Kessler, H J; Ketel, T; Kiryluk, J; Kiselev, Yu F; Krämer, Dietrich; Kröger, W; Kurek, K; Kyynäräinen, J; Lamanna, M; Landgraf, U; Le Goff, J M; Lehár, F; de Lesquen, A; Lichtenstadt, J; Litmaath, M; Magnon, A; Mallot, G K; Marie, F; Martin, A; Martino, J; Matsuda, T; Mayes, B W; McCarthy, J S; Medved, K S; Meyer, W T; Van Middelkoop, G; Miller, D; Miyachi, Y; Mori, K; Moromisato, J H; Nassalski, J P; Niinikoski, T O; Oberski, J; Ogawa, A; Ozben, C; Pereira, H; Perrot-Kunne, F; Peshekhonov, V D; Piegaia, R; Pinsky, L; Platchkov, S K; Pló, M; Pose, D; Postma, H; Pretz, J; Puntaferro, R; Rädel, G; Reicherz, G; Roberts, J; Rodríguez, M; Rondio, Ewa; Sabo, I; Saborido, J; Sandacz, A; Savin, I A; Schiavon, R P; Sichtermann, E P; Simeoni, F; Smirnov, G I; Staude, A; Steinmetz, A; Stiegler, U; Stuhrmann, H B; Tessarotto, F; Thers, D; Tlaczala, W; Tripet, A; Ünel, G; Velasco, M; Vogt, J; Voss, Rüdiger; Whitten, C; Willumeit, R; Windmolders, R; Wislicki, W; Witzmann, A; Zanetti, A M; Zaremba, K; Zhao, J
1999-01-01
We present the results of the spin asymmetries $A_1$ of the proton and the deuteron in the kinematic region extending down to $x=6\\cdot 10^{-5}$ and $Q^2=0.01$ GeV$^2$. The data were taken with a dedicated low $x$ trigger, which required hadron detection in addition to the scattered muon, so as to reduce the background at low $x$. The results complement our previous measurements and the two sets are consistent in the overlap region. No sig\\-ni\\-fi\\-cant spin effects are found in the newly explored region.
Measurements of the Deuteron Elastic Structure Function A(Q2) for 0.7
International Nuclear Information System (INIS)
L. C. Alexa; B. D. Anderson; K. A. Aniol; K. Arundell; L. Auerbach; F. T. Baker; J. Berthot; P. Y. Bertin; W. Bertozzi; L. Bimbot; W. U. Boeglin; E. J. Brash; V. Breton; H. Breuer; E. Burtin; J. R. Calarco; L. S. Cardman; C. Cavata; C.-C. Chang; J.-P. Chen; E. Chudakov; E. Cisbani; D. S. Dale; N. Degrande; R. De Leo; A. Deur; N. d'Hose; B. Diederich; J. J. Domingo; M. B. Epstein; L. A. Ewell; J. M. Finn; K. G. Fissum; H. Fonvieille; B. Frois; S. Frullani; H. Gao; J. Gao; F. Garibaldi; A. Gasparian,; S. Gilad; R. Gilman; A. Glamazdin; C. Glashausser; J. Gomez; V. Gorbenko; J.-O. Hansen; R. Holmes; M. Holtrop; C. Howell; G. M. Huber; C. Hyde-Wright; M. Iodice; C. W. de Jager; S. Jaminion; J. Jardillier; M. K. Jones; C. Jutier,; W. Kahl; S. Kato; A. T. Katramatou; J. J. Kelly; S. Kerhoas; A. Ketikyan; M. Khayat; K. Kino; L. H. Kramer; K. S. Kumar; G. Kumbartzki; M. Kuss; G. Lavessiere; A. Leone; J. J. LeRose; M. Liang; R. A. Lindgren; N. Liyanage; G. J. Lolos; R. W. Lourie; R. Madey,; K. Maeda; S. Malov; D. M. Manley; D. J. Margaziotis; P. Markowitz; J. Marroncle; J. Martino; C. J. Martoff; K. McCormick; J. McIntyre; R. L. J. van der Meer; S. Mehrabyan; Z.-E. Meziani; R. Michaels; G. W. Miller; J. Y. Mougey; S. K. Nanda; D. Neyret; E. A. J. M. Offermann; Z. Papandreou; C. F. Perdrisat; R. Perrino; G. G. Petratos; S. Platchkov; R. Pomatsalyuk; D. L. Prout; V. A. Punjabi; T. Pussieux; G. Quemener; R. D. Ransome; O. Ravel; Y. Roblin; D. Rowntree; G. Rutledge; P. M. Rutt; A. Saha; T. Saito; A. J. Sarty; A. Serdarevic,; T. Smith; K. Soldi; P. Sorokin; P. A. Souder; R. Suleiman; J. A. Templon; T. Terasawa; L. Todor; H. Tsubota; H. Ueno; P. E. Ulmer; G. M. Urciuoli; L. Van Hoorebeke; P. Vernin; B. Vlahovic; H. Voskanyan; J. W. Watson; L. B. Weinstein; K. Wijesooriya; R. Wilson; B. B. Wojtsekhowski; D. G. Zainea; W-M. Zhang; J. Zhao; Z.-L. Zhou
1999-01-01
The deuteron elastic structure function A(Q 2 ) has been extracted in the range 0.7 2 2 from cross section measurements of elastic electron-deuteron scattering in coincidence using the Hall A Facility of Jefferson Laboratory. The data are compared to theoretical models, based on the impulse approximation with the inclusion of meson-exchange currents, and to predictions of quark dimensional scaling and perturbative quantum chromodynamics
Relativistic analysis of the electromagnetic properties of the deuteron
International Nuclear Information System (INIS)
Hummel, E.
1991-01-01
In this thesis the electromagnetic properties of the deuteron are studied. A relativistic description is constructed starting from a quasi-potential approach of the bethe-Salpeter equation, which treats dynamical and electromagnetical properties in a consistent way. This is applied on elastic as well as inelastic electron-deuteron scattering. In ch. 2 the formalism of electromagnetic scattering in the one-photon exchange approximation is described. The general form of the electromagnetic deuteron current operator and the consequences of current conservation are discussed. The deuteron current operator is constructed in a simple quasipotential approximation model. Ch. 3 discusses elastic electron-deuteron scattering. The ρπγ and ωεγ MEC contributions are taken into account and the results are compared to the experimental data for both the electric and magnetic form factor. In particular, the usual non-relativistic reduction of the two-body current operators is studied. In ch. 4 some improvements are made on the simple approximation model. In this improved model at the same time both elastic and breakup processes can be treated. The differences with the simple model are the treatment of the initial and final states and the propagator structure. The isovector two-body currents are constructed using the OBE-model, where the complications due to the use of strong form factors at the meson-nucleon vertices are accounted for. The results for elastic scattering using the improved model are compared with the results of ch. 3. Finally in ch. 5 the model developed in ch. 4 is used to describe the electro-desintegration of the deuteron. The recent experiments at NIKHEF are discussed in the PWIA approximation also with FSI included. In the analysis of the threshold experiments the π-MEC are included. In both experiments relativistic effects and in the threshold experiment also the controversy about the form factor in the MEC, are discussed. (author). 61 refs.; 40 figs
Inelastic scattering of fast electrons by crystals
International Nuclear Information System (INIS)
Allen, L.J.; Josefsson, T.W.
1995-01-01
Generalized fundamental equations for electron diffraction in crystals, which include the effect of inelastic scattering described by a nonlocal interaction, are derived. An expression is obtained for the cross section for any specific type of inelastic scattering (e.g. inner-shell ionization, Rutherford backscattering). This result takes into account all other (background) inelastic scattering in the crystal leading to absorption from the dynamical Bragg-reflected beams, in practice mainly due to thermal diffuse scattering. There is a contribution to the cross section from all absorbed electrons, which form a diffuse background, as well as from the dynamical electrons. The approximations involved, assuming that the interactions leading to inelastic scattering can be described by a local potential are discussed, together with the corresponding expression for the cross section. It is demonstrated by means of an example for K-shell electron energy loss spectroscopy that nonlocal effects can be significant. 47 refs., 4 figs
Petrovici, Alex; Adhikary, Amitava; Kumar, Anil; Sevilla, Michael D.
2015-01-01
Radiation-produced electrons initiate various reaction processes that are important to radiation damage to biomolecules. In this work, the site of attachment of the prehydrated electrons with methylacetoacetate (MAA, CH3-CO-CH2-CO-OCH3) at 77 K and subsequent reactions of the anion radical (CH3-CO•−-CH2-CO-OCH3) in the temperature range (77 to ca. 170 K) have been investigated in homogeneous H2O and D2O aqueous glasses by electron spin resonance (ESR) spectroscopy. At 77 K, the prehydrated electron attaches to MAA forming the anion radical in which the electron is delocalized over the two carbonyl groups. This species readily protonates to produce the protonated electron adduct radical CH3-C(•)OH-CH2-CO-OCH3. The ESR spectrum of CH3-C(•)OH-CH2-CO-OCH3 in H2O shows line components due to proton hyperfine couplings of the methyl and methylene groups. Whereas, the ESR spectrum of CH3-C(•)OH-CH2-CO-OCH3 in D2O glass shows only the line components due to proton hyperfine couplings of CH3 group. This is expected since the methylen protons in MAA are readily exchangeable in D2O. On stepwise annealing to higher temperatures (ca. 150 to 170 K), CH3-C(•)OH-CH2-CO-OCH3 undergoes bimolecular H-atom abstraction from MAA to form the more stable radical, CH3-CO-CH•-CO-OCH3. Theoretical calculations using density functional theory (DFT) support the radical assignments. PMID:25255751
Calculation of electron-helium scattering
International Nuclear Information System (INIS)
Fursa, D.V.; Bray, I.
1994-11-01
We present the Convergent Close-Coupling (CCC) theory for the calculation of electron-helium scattering. We demonstrate its applicability at a range of projectile energies of 1.5 to 500 eV to scattering from the ground state to n ≤3 states. Excellent agreement with experiment is obtained with the available differential, integrated, ionization, and total cross sections, as well as with the electron-impact coherence parameters up to and including the 3 3 D state excitation. Comparison with other theories demonstrates that the CCC theory is the only general reliable method for the calculation of electron helium scattering. (authors). 66 refs., 2 tabs., 24 figs
Large enhancement of deuteron polarization with frequency modulated microwaves
AUTHOR|(CDS)2067425; Arik, S; Arvidson, A; Badelek, B; Ballintijn, M K; Bardin,; Baum, G; Berglund, P; Betev, L; Birda, I G; Birsa, R; Bjrkholm, P; Bonner, B E; de Botton, N; Boutemeur, M; Bradamante, Franco; Bressan, A; Brullc, A; Buchanan, J; Bültmann, S; Burtin, E; Cavata, C; Chen, J P; Clement, J; Clocchiatti, M; Corcoran, M D; Crabb, D; Cranshaw, J; Çuhadar-Dönszelmann, T; Deshpande, S; Dalla Torre, A; Van Dantzig, R; Dhawan, S; Dulya, C; Dyring, A; Eichblatt, S; Faivre, Jean-Claude; Fasching, D; Day, D; Feinstein, F; Fernández, C; Frois, B; Garabatos, C; Garzón, J A; Gaussiran, T; Giorgi, M; von Goeler, E; Goloutvin, Igor A; Gómez, A; Gracia, G; De Groot, N; Grosse-Perdekamp, M; Gülmez, E; Hasegawa, T; Hautle, P; Hayashi, N; Heusch, C A; Horikawa, D; von Harrach, N; Hughes, V W; Igo, G; Ishimoto, S; Iwata, T; De Jong, M; Kabu, E M; Kageya, T; Kaiser, R; Karev, A; Kessler, H J; Ketel, T J; Kiryushin, Yu T; Kishi, A; Kisselev, Yu; Klostermann, L; Krämer, Dietrich; Kukhtin, V; Kyynarinen, J; Lamanna, M; Landgraf, U; Lau, V; Krivokhijinea, K; Layda, T; Le Go, J M; Lehár, F; de Lesquen, A; Lichtenstadt, J; Lindqvist, T; Litmaath, M; López-Ponte, S; Loewe, M; Magnon, A; Mallot, G K; Marie, F; Martin, A; Martino, J; Matsuda, T; Mayes, B; McCarthy, J S; van Middelkoop, K; Medved, G; Miller, D; Mitchell, J; Mori, K; Moromisato, J; Mutchler, G S; Nagaitsev, A; Nassalski, J; Naumann, Lutz; Neganov, B; Niinikoski, T O; Oberski, J E J; Ogawa, A; Okumi, S; Ozben, C S; Penzo, Aldo L; Pérez, C A; Perrot-Kunne, F; Piegaia, R; Pinsky, L; Platchkov, S; Pló, M; Pose, D; Postma, D; Peshekhonov, H; Pretz, J; Pussieux, T; Pyrlik, J; Reyhancan, I; Rieubland, Jean Michel; Rijllart, A; Roberts, J B; Rock, S E; Rodríguez, M; Rondio, E; Rondon, O; Ropelewski, Leszek; Rosado, A; Sabo, I; Saborido, J; Salvato, G; Sandacz, A; Sanders, D; Savin, I; Schiavon, Paolo; Schüler, K P; Segel, R; Seitz, R; Semertzidis, Y; Sergeev, S; Sever, F; Shanahan, P; Sichtermann, E P; Smirnov, G; Staude, A; Steinmetz, A; Stuhrmann, H; Teichert, K M; Tessarotto, F; Thiel, W; Velasco, M; Vogt, J; Voss, R; Weinstein, R; Whitten, C; Willumeit, R; Windmolders, R; Wislicki, W; Witzmann, A; Yañez, A; Zanetti, A M; Zhao, J; Zamiatin, N I
1996-01-01
We report a large enhancement of 1.7 in deuteron polarization up to values of 0.6 due to frequency modulation of the polarizing microwaves in a two liters polarized target using the method of dynamic nuclear polarization. This target was used during a deep inelastic polarized muon-deuteron scattering experiment at CERN. Measurements of the electron paramagnetic resonance absorption spectra show that frequency modulation gives rise to additional microwave absorption in the spectral wings. Although these results are not understood theoretically, they may provide a useful testing ground for the deeper understanding of dynamic nuclear polarization.
Electron scattering on metal clusters and fullerenes
International Nuclear Information System (INIS)
Solov'yov, A.V.
2001-01-01
This paper gives a survey of physical phenomena manifesting themselves in electron scattering on atomic clusters. The main emphasis is made on electron scattering on fullerenes and metal clusters, however some results are applicable to other types of clusters as well. This work is addressed to theoretical aspects of electron-cluster scattering, however some experimental results are also discussed. It is demonstrated that the electron diffraction plays important role in the formation of both elastic and inelastic electron scattering cross sections. It is elucidated the essential role of the multipole surface and volume plasmon excitations in the formation of electron energy loss spectra on clusters (differential and total, above and below ionization potential) as well as the total inelastic scattering cross sections. Particular attention is paid to the elucidation of the role of the polarization interaction in low energy electron-cluster collisions. This problem is considered for electron attachment to metallic clusters and the plasmon enhanced photon emission. Finally, mechanisms of electron excitation widths formation and relaxation of electron excitations in metal clusters and fullerenes are discussed. (authors)
Diffusive scattering of electrons by electron holes around injection fronts
Vasko, I. Y.; Agapitov, O. V.; Mozer, F. S.; Artemyev, A. V.; Krasnoselskikh, V. V.; Bonnell, J. W.
2017-03-01
Van Allen Probes have detected nonlinear electrostatic spikes around injection fronts in the outer radiation belt. These spikes include electron holes (EH), double layers, and more complicated solitary waves. We show that EHs can efficiently scatter electrons due to their substantial transverse electric fields. Although the electron scattering driven by EHs is diffusive, it cannot be evaluated via the standard quasi-linear theory. We derive analytical formulas describing local electron scattering by a single EH and verify them via test particle simulations. We show that the most efficiently scattered are gyroresonant electrons (crossing EH on a time scale comparable to the local electron gyroperiod). We compute bounce-averaged diffusion coefficients and demonstrate their dependence on the EH spatial distribution (latitudinal extent and spatial filling factor) and individual EH parameters (amplitude of electrostatic potential, velocity, and spatial scales). We show that EHs can drive pitch angle scattering of ≲5 keV electrons at rates 10-2-10-4 s-1 and, hence, can contribute to electron losses and conjugated diffuse aurora brightenings. The momentum and pitch angle scattering rates can be comparable, so that EHs can also provide efficient electron heating. The scattering rates driven by EHs at L shells L ˜ 5-8 are comparable to those due to chorus waves and may exceed those due to electron cyclotron harmonics.
Electron scattering in the interacting boson model
Dieperink, AEL; Iachello, F; Rinat, A; Creswell, C
1978-01-01
It is suggested that the interacting boson model be used in the analysis of electron scattering data. Qualitative features of the expected behavior of the inelastic excitation of some 2 ÷ states inthe transitional Sm-Nd region are discussed
3He electron scattering sum rules
International Nuclear Information System (INIS)
Kim, Y.E.; Tornow, V.
1982-01-01
Electron scattering sum rules for 3 He are derived with a realistic ground-state wave function. The theoretical results are compared with the experimentally measured integrated cross sections. (author)
Energy Technology Data Exchange (ETDEWEB)
Airapetian, A. [Giessen Univ. (Germany). Physikalisches Inst.; Michigan Univ., Ann Arbor, MI (United States). Randall Lab. of Physics; Akopov, N. [Yerevan Physics Institute (Armenia); Akopov, Z. [DESY Hamburg (Germany)] [and others; Collaboration: HERMES Collaboration
2012-12-15
Multiplicities in semi-inclusive deep-inelastic scattering are presented for each charge state of {pi}{sup {+-}} and K{sup {+-}} mesons. The data were collected by the HERMES experiment at the HERA storage ring using 27.6 GeV electron and positron beams incident on a hydrogen or deuterium gas target. The results are presented as a function of the kinematic quantities x{sub B}, Q{sup 2}, z, and P{sub h} {sub perpendicular} {sub to}. They represent a unique data set for identified hadrons that will significantly enhance our understanding of the fragmentation of quarks into final-state hadrons in deep-inelastic scattering.
35 years of electron scattering
International Nuclear Information System (INIS)
Walecka, J.D.
1986-01-01
Historical aspects of electron reaction physics are presented. The presently understood picture of nuclear structure and the electron-nucleus interactions are discussed within the framework of the standard model
Effective exchange potentials for electronically inelastic scattering
International Nuclear Information System (INIS)
Schwenke, D.W.; Staszewska, G.; Truhlar, D.G.
1983-01-01
We propose new methods for solving the electron scattering close coupling equations employing equivalent local exchange potentials in place of the continuum-multiconfiguration-Hartree--Fock-type exchange kernels. The local exchange potentials are Hermitian. They have the correct symmetry for any symmetries of excited electronic states included in the close coupling expansion, and they have the same limit at very high energy as previously employed exchange potentials. Comparison of numerical calculations employing the new exchange potentials with the results obtained with the standard nonlocal exchange kernels shows that the new exchange potentials are more accurate than the local exchange approximations previously available for electronically inelastic scattering. We anticipate that the new approximations will be most useful for intermediate-energy electronically inelastic electron--molecule scattering
Energy Technology Data Exchange (ETDEWEB)
Airapetian, A. [Giessen Univ. (Germany). Physikalisches Inst.; Michigan Univ., Ann Arbor, MI (United States). Randall Laboratory of Physics; Akopov, N. [Yerevan Physics Institute (Armenia); Akopov, Z. [DESY Hamburg (DE)] (and others)
2012-04-15
The azimuthal cos {phi} and cos 2{phi} modulations of the distribution of hadrons produced in unpolarized semi-inclusive deep-inelastic scattering of electrons and positrons off hydrogen and deuterium targets have been measured in the Hermes experiment. For the first time these modulations were determined in a four-dimensional kinematic space for positively and negatively charged pions and kaons separately, as well as for unidentified hadrons. These azimuthal dependences are sensitive to the transverse motion and polarization of the quarks within the nucleon via, e.g., the Cahn, Boer-Mulders and Collins effects.
International Nuclear Information System (INIS)
Gonzalez Trotter, D.E.; Meneses, F. Salinas; Tornow, W.; Howell, C.R.; Chen, Q.; Crowell, A.S.; Roper, C.D.; Walter, R.L.; Schmidt, D.; Witala, H.; Gloeckle, W.; Tang, H.; Zhou, Z.; Slaus, I.
2006-01-01
We report on results of a kinematically complete neutron-deuteron breakup experiment performed at Triangle Universities Nuclear Laboratory using an E n =13 MeV incident neutron beam. The 1 S 0 neutron-neutron scattering length a nn has been determined for four production angles of the neutron-neutron final-state interaction configuration. The absolute cross-section data were analyzed with rigorous three-nucleon calculations. Our average value of a nn =-18.7±0.7 fm is in excellent agreement with a nn =-18.6±0.4 fm obtained from capture experiments of negative pions on deuterons. We also performed a shape analysis of the final-state interaction cross-section enhancements by allowing the normalization of the data to float. From these relative data, we obtained an average value of a nn =-18.8±0.5 fm, in agreement with the result obtained from the absolute cross-section measurements. Our result deviates from the world average of a nn =-16.7±0.5 fm determined from previous kinematically complete neutron-deuteron breakup experiments, including the most recent one carried out at Bonn. However, this low value for a nn is at variance with theoretical expectation and other experimental information about the sign of charge-symmetry breaking of the nucleon-nucleon interaction. In agreement with theoretical predictions, no evidence was found of significant three-nucleon force effects on the neutron-neutron final-state interaction cross sections
Indirect processes in electron-ion scattering
International Nuclear Information System (INIS)
Bottcher, C.; Griffin, D.C.; Pindzola, M.S.; Phaneuf, R.A.
1983-10-01
A summary is given of an informal workshop held at Oak Ridge National Laboratory on June 22-23, 1983, in which the current status of theoretical calculations of indirect processes in electron-ion scattering was reviewed. Processes of particular interest in astrophysical and fusion plasmas were emphasized. Topics discussed include atomic structure effects, electron-impact ionization, and dielectronic recombination
Pygmy resonances probed with electron scattering
International Nuclear Information System (INIS)
Bertulani, C.A.
2007-01-01
Pygmy resonances in light nuclei excited in electron scattering are discussed. These collective modes will be explored in future electron-ion colliders such as ELISe/FAIR (spokesperson: Haik Simon - GSI). Response functions for direct breakup are explored with few-body and hydrodynamical models, including the dependence upon final state interactions
Indirect processes in electron-ion scattering
Energy Technology Data Exchange (ETDEWEB)
Bottcher, C.; Griffin, D.C.; Pindzola, M.S.; Phaneuf, R.A.
1983-10-01
A summary is given of an informal workshop held at Oak Ridge National Laboratory on June 22-23, 1983, in which the current status of theoretical calculations of indirect processes in electron-ion scattering was reviewed. Processes of particular interest in astrophysical and fusion plasmas were emphasized. Topics discussed include atomic structure effects, electron-impact ionization, and dielectronic recombination.
Nonelastic electron scattering in mercury telluride
Malik, O P
2002-01-01
By exact solution of the Boltzmann equation, the nonequilibrium charge carrier distribution function is obtained. In the temperature range 4.2 - 300 K, main electron scattering mechanisms are considered by taking into account the nonelastic electron interaction with optical vibrations of the crystal lattice.
Electron Raman scattering in quantum well wires
International Nuclear Information System (INIS)
Zhao Xiangfu; Liu Cuihong
2007-01-01
Electron Raman scattering (ERS) is investigated in a semiconductor quantum well wire (QWW) of cylindrical geometry for T=0K and neglecting phonon-assisted transitions. The differential cross-section (DCS) involved in this process is calculated as a function of a scattering frequency and the cylindrical radius. Electron states are confined within a QWW. Single parabolic conduction and valence bands are assumed. The selection rules are studied. Singularities in the spectra are interpreted for various cylindrical radii. ERS discussed here can provide direct information about the electron band structure of the system
Electron scattering by trapped fermionic atoms
International Nuclear Information System (INIS)
Wang Haijun; Jhe, Wonho
2002-01-01
Considering the Fermi gases of alkali-metal atoms that are trapped in a harmonic potential, we study theoretically the elastic and inelastic scattering of the electrons by the trapped Fermi atoms and present the corresponding differential cross sections. We also obtain the stopping power for the cases that the electronic state as well as the center-of-mass state are excited both separately and simultaneously. It is shown that the elastic scattering process is no longer coherent in contrast to the electron scattering by the atomic Bose-Einstein condensate (BEC). For the inelastic scattering process, on the other hand, the differential cross section is found to be proportional to the 2/3 power of the number of the trapped atoms. In particular, the trapped fermionic atoms display the effect of ''Fermi surface,'' that is, only the energy levels near the Fermi energy have dominant contributions to the scattering process. Moreover, it is found that the stopping power scales as the 7/6 power of the atomic number. These results are fundamentally different from those of the electron scattering by the atomic BEC, mainly due to the different statistics obeyed by the trapped atomic systems
Parity violation in deep inelastic electron scattering
International Nuclear Information System (INIS)
Taylor, R.E.
1979-11-01
Neutral currents in electron scattering and the Weinberg-Salam model are reviewed. This generally accepted model is consistent with experimental results from neutrino interactions; an appropriate deep inelastic electron scattering experiment would measure couplings that don't involve neutrinos to see if they are also correctly described by the theory. The SLAC-Yale experiment measures a difference in the e-d inelastic cross section for right- and left-handed electrons. The polarized source, beam monitors, scattering experiment, checks of helicity dependence, and results are described. It is concluded that the data obtained are in agreement with the Weinberg-Salam model, and that the best value of sin 2 theta/sub W/ for these data is in excellent agreement with the average values of that parameter deduced from neutrino experiments. Future experiments with polarized electrons are discussed. 12 figures, 2 tables
Tornow, W.; Howell, C. R.; Crowell, A. S.
2013-12-01
In order to confirm or refute the present discrepancy between data and calculation for the neutron-neutron quasi-free scattering cross section in the neutron-deuteron breakup reaction, we describe a new experimental approach currently being pursued at TUNL.
International Nuclear Information System (INIS)
Tornow, W.; Howell, C. R.; Crowell, A. S.
2013-01-01
In order to confirm or refute the present discrepancy between data and calculation for the neutron–neutron quasi-free scattering cross section in the neutron–deuteron breakup reaction, we describe a new experimental approach currently being pursued at TUNL. (author)
International Nuclear Information System (INIS)
Oka, Takamitsu.
1979-03-01
We make analyses of the parity-violating asymmetries of electron-deuteron and electron-proton deep inelastic scatterings including sea quark contribution and adopting three different kinds of parton distribution functions. Both results from electron-deuteron and from electron-proton scatterings coincide with the prediction of the Weinberg-Salam model. Our results are found to be insensitive to the difference among the three kinds of parton distribution functions. We also study the x-, y-, and sin 2 theta sub(w)-dependences of A/Q 2 in the Weinberg-Salam model. Experiments at higher y value will be useful for more precise determination of the Weinberg angle theta sub(w). (author)
Deep inelastic electron and muon scattering
International Nuclear Information System (INIS)
Taylor, R.E.
1975-07-01
From the review of deep inelastic electron and muon scattering it is concluded that the puzzle of deep inelastic scattering versus annihilation was replaced with the challenge of the new particles, that the evidence for the simplest quark-algebra models of deep inelastic processes is weaker than a year ago. Definite evidence of scale breaking was found but the specific form of that scale breaking is difficult to extract from the data. 59 references
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
Electron Scattering From Atoms, Molecules, Nuclei, and Bulk Matter
Whelan, Colm T
2005-01-01
Topics that are covered include electron scattering in the scanning TEM; basic theory of inelastic electron imaging; study of confined atoms by electron excitation; helium bubbles created in extreme pressure with application to nuclear safety; lithium ion implantation; electron and positron scattering from clusters; electron scattering from physi- and chemi-absorbed molecules on surfaces; coincidence studies; electron scattering from biological molecules; electron spectroscopy as a tool for environmental science; electron scattering in the presence of intense fields; electron scattering from astrophysical molecules; electon interatctions an detection of x-ray radiation.
Modern topics in electron scattering
Frois, Bernard
1991-01-01
This book summarizes the considerable progress recently achieved in the understanding of nucleon and nuclear structure by using high energy electrons as a probe. A collection of papers discusses in detail the new frontiers of this field. Experimental and theoretical articles cover topics such as the structure of the nucleon, nucleon distributions, many-body correlations, non-nucleonic degrees of freedom and few-body systems. This book is an up-to-date introduction to the research planned with continuous beam electron accelerators.
AUTHOR|(CDS)2067425; Arik, E; Arvidson, A; Badelek, B; Bardin, G; Baum, G; Berglund, P; Betev, L; Birsa, R; Björkholm, P; De Botton, N R; Boutemeur, M; Bradamante, Franco; Bravar, A; Bressan, A; Bültmann, S; Burtin, E; Cavata, C; Crabb, D; Cranshaw, J; Çuhadar-Dönszelmann, T; Dalla Torre, S; Van Dantzig, R; Derro, B R; Deshpande, A A; Dhawan, S K; Dulya, C M; Dyring, A; Eichblatt, S; Faivre, Jean-Claude; Fasching, D; Feinstein, F; Fernández, C; Forthmann, S; Frois, Bernard; Gallas, A; Garzón, J A; Gilly, H; Giorgi, M A; von Goeler, E; Görtz, S; Golutvin, I A; Gracia, G; De Groot, N; Grosse-Perdekamp, M; Haft, K; Von Harrach, D; Hasegawa, T; Hautle, P; Hayashi, N; Heusch, C A; Horikawa, N; Hughes, V W; Igo, G; Ishimoto, S; Iwata, T; Kabuss, E M; Kageya, T; Karev, A G; Kessler, H J; Ketel, T; Kiryluk, J; Kiryushin, Yu T; Kishi, A; Kiselev, Yu F; Klostermann, L; Krämer, Dietrich; Krivokhizhin, V G; Kröger, W; Kukhtin, V V; Kurek, K; Kyynäräinen, J; Lamanna, M; Landgraf, U; Le Goff, J M; Lehár, F; de Lesquen, A; Lichtenstadt, J; Lindqvist, T; Litmaath, M; Loewe, M; Magnon, A; Mallot, G K; Marie, F; Martin, A; Martino, J; Matsuda, T; Mayes, B W; McCarthy, J S; Medved, K S; Meyer, W T; Van Middelkoop, G; Miller, D; Miyachi, Y; Mori, K; Moromisato, J H; Nagaitsev, A P; Nassalski, J P; Naumann, Lutz; Niinikoski, T O; Oberski, J; Ogawa, A; Ozben, C; Pereira, H; Perrot-Kunne, F; Peshekhonov, V D; Piegia, R; Pinsky, L; Platchkov, S K; Pló, M; Pose, D; Postma, H; Pretz, J; Puntaferro, R; Pussieux, T; Rädel, G; Rijllart, A; Reicherz, G; Roberts, J; Rock, S E; Rodríguez, M; Rondio, Ewa; Ropelewski, Leszek; Sabo, I; Saborido, J; Sandacz, A; Savin, I A; Schiavon, R P; Schiller, A; Schüler, K P; Seitz, R; Semertzidis, Y K; Sergeev, S; Shanahan, P; Sichtermann, E P; Simeoni, F; Smirnov, G I; Staude, A; Steinmetz, A; Stiegler, U; Stuhrmann, H B; Szleper, M; Tessarotto, F; Thers, D; Tlaczala, W; Tripet, A; Ünel, G; Velasco, M; Vogt, J; Voss, Rüdiger; Whitten, C; Windmolders, R; Willumeit, R; Wislicki, W; Witzmann, A; Ylöstalo, J; Zanetti, A M; Zaremba, K; Zamiatin, N I; Zhao, J
1998-01-01
We present the final results of the spin asymmetries $A_1$ and the spin structure functions $g_1$ of the proton and the deuteron in the kinematic range $0.0008
Electron scattering from sodium at intermediate energies
International Nuclear Information System (INIS)
Mitroy, J.; McCarthy, I.E.
1986-10-01
A comprehensive comparison is made between theoretical calculations and experimental data for intermediate energy (≥ 10 eV) electron scattering from sodium vapour. The theoretical predictions of coupled-channels calculations (including one, two or four channels) do not agree with experimental values of the differential cross sections for elastic scattering or the resonant 3s to 3p excitation. Increasingly-more-sophisticated calculations, incorporating electron correlations in the target states, and also including core-excited states in the close-coupling expansion, are done at a few selected energies in an attempt to isolate the cause of the discrepancies between theory and experiment. It is found that these more-sophisticated calculations give essentially the same results as the two- and four-channel calculations using Hartree-Fock wavefunctions. Comparison of the sodium high-energy elastic differential cross sections with those of neon suggests that the sodium differential cross section experiments may suffer from systematic errors. There is also disagreement, at the higher energies, between theoretical values for the scattering parameters and those that are derived from laser-excited superelastic scattering and electron photon coincidence experiments. When allowance is made for the finite acceptance angle of the electron spectrometers used in the experiments by convoluting the theory with a function representing the distribution of electrons entering the electron spectrometer it is found that the magnitudes of the differences between theory and experiment are reduced
Electron scattering and nuclear structure
International Nuclear Information System (INIS)
Wolynec, E.
1985-01-01
A review of the historical development and the theory necessary to the interpretation of the experimental results is made. Some measurement techniques, experimental results and the technique of analysis of these data are presented. Future perspectives, due to the appearence of continous electron current accelerators, in this field of study are discussed. (L.C.) [pt
Inelastic electron scattering from surfaces
International Nuclear Information System (INIS)
Tong, S.Y.; Mills, D.L.
1992-01-01
This report contains highlights of accomplishments of the past year, for the University of California, Irvine and the University of Wisconsin, Milwaukee collaboration on surface excitations, and their interactions with low energy electrons. In addition, we present a summary of future research to be carried out in the coming grant year
Dynamic properties of electrons in solids by neutron scattering
International Nuclear Information System (INIS)
Lovesey, S.W.
1980-12-01
Illustrative cases of the use of neutron scattering in the study of the electronic properties of materials discussed here include scattering by localised electrons, narrow band materials and electron plasmas. (U.K.)
Neutrino oscillations and neutrino-electron scattering
International Nuclear Information System (INIS)
Kayser, B.; Rosen, S.P.
1980-10-01
Neutrino flavor oscillations can significantly alter the cross section for neutrino-electron scattering. As a result, such oscillations can affect the comparison between existing reactor data and theories of neutral-current processes. They may also lead to strikingly large effects in high-energy accelerator experiments
Electron scattering in the interacting boson model
International Nuclear Information System (INIS)
Dieperink, A.E.L.; Iachello, F.; Creswell, C.
1978-01-01
It is suggested that the interacting boson model be used in the analysis of electron scattering data. Qualitative features of the expected behavior of the inelastic excitation of some 2 + states in the transitional Sm-Nd region are discussed. (Auth.)
Electron scattering and reactions from exotic nuclei
International Nuclear Information System (INIS)
Karataglidis, S.
2017-01-01
The SCRIT and FAIR/ELISe experiments are the first to attempt to measure directly electron scattering form factors from nuclei far from stability. This will give direct information for the (one-body) charge densities of those systems, about which there is little information available. The SCRIT experiment will be taking data for medium-mass exotic nuclei, while the electron-ion collider at ELISe, when constructed, will be able to measure form factors for a wide range of exotic nuclei, as available from the radioactive ion beams produced by the FAIR experiment. Other facilities are now being proposed, which will also consider electron scattering from exotic nuclei at higher energies, to study short-range correlations in exclusive reactions. This review will consider all available information concerning the current status (largely theoretical) of electron scattering from exotic nuclei and, where possible, complement such information with equivalent information concerning the neutron densities of those exotic systems, as obtained from intermediate energy proton scattering. The issue of long- and short-range correlations will be discussed, and whether extending such studies to the exotic sector will elicit new information. (orig.)
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
Electron scattering and reactions from exotic nuclei
Energy Technology Data Exchange (ETDEWEB)
Karataglidis, S. [University of Johannesburg, Department of Physics, Auckland Park (South Africa); University of Melbourne, School of Physics, Victoria (Australia)
2017-04-15
The SCRIT and FAIR/ELISe experiments are the first to attempt to measure directly electron scattering form factors from nuclei far from stability. This will give direct information for the (one-body) charge densities of those systems, about which there is little information available. The SCRIT experiment will be taking data for medium-mass exotic nuclei, while the electron-ion collider at ELISe, when constructed, will be able to measure form factors for a wide range of exotic nuclei, as available from the radioactive ion beams produced by the FAIR experiment. Other facilities are now being proposed, which will also consider electron scattering from exotic nuclei at higher energies, to study short-range correlations in exclusive reactions. This review will consider all available information concerning the current status (largely theoretical) of electron scattering from exotic nuclei and, where possible, complement such information with equivalent information concerning the neutron densities of those exotic systems, as obtained from intermediate energy proton scattering. The issue of long- and short-range correlations will be discussed, and whether extending such studies to the exotic sector will elicit new information. (orig.)
T-odd polarization observables in deuteron electrodisintegration
International Nuclear Information System (INIS)
Rekalo, M.P.; Gakh, G.I.; Rekalo, A.P.
1996-01-01
It is considered such simplest T-odd polarization observables of the deuteron disintegration as proton polarization in d(e, e' p-bar)n and the asymmetry in the scattering of unpolarized electrons by a vector-polarized target, d-bar (e, e' p)n. The θ dependence of theses observables has been studied. The procedure of making the conserved electromagnetic current has an essential influence on the final θ dependence of the T-odd polarization observables [ru
Scattering of ultrarelativistic electrons in ultrathin crystals
Directory of Open Access Journals (Sweden)
N.F. Shul'ga
2017-06-01
Full Text Available Quantum theory is proposed of high energy electrons scattering in ultrathin crystals. This theory is based upon a special representation of the scattering amplitude in the form of an integral over the surface surrounding the crystal, and on the spectral method of determination of the wave function. The comparison is performed of quantum and classical differential scattering cross-sections in the transitional range of crystal thicknesses, from those at which the channeling phenomenon is not developed up to those at which it is established. It is shown that in this thickness range the quantum scattering cross-section, unlike the classical one, contains sharp peaks corresponding to some specific scattering angles, that is connected with the diffraction of the incident plane wave onto the periodically distributed crystal atomic strings. It is shown that the value of the scattering cross-section in the peaks varies periodically with the change of the target thickness. We note that this must lead to a new interference effect in radiation that is connected with the rearrangement of incident wave packet in transitional area of crystal thicknesses.
Scattering of ultrarelativistic electrons in ultrathin crystals
Energy Technology Data Exchange (ETDEWEB)
Shul' ga, N.F., E-mail: shulga@kipt.kharkov.ua [National Science Center “Kharkov Institute of Physics and Technology”, 1, Akademichna str., Kharkiv, 61108 (Ukraine); Karazin Kharkiv National University, 4, Svobody sq., Kharkiv, 61000 (Ukraine); Shulga, S.N. [National Science Center “Kharkov Institute of Physics and Technology”, 1, Akademichna str., Kharkiv, 61108 (Ukraine); Karazin Kharkiv National University, 4, Svobody sq., Kharkiv, 61000 (Ukraine)
2017-06-10
Quantum theory is proposed of high energy electrons scattering in ultrathin crystals. This theory is based upon a special representation of the scattering amplitude in the form of an integral over the surface surrounding the crystal, and on the spectral method of determination of the wave function. The comparison is performed of quantum and classical differential scattering cross-sections in the transitional range of crystal thicknesses, from those at which the channeling phenomenon is not developed up to those at which it is established. It is shown that in this thickness range the quantum scattering cross-section, unlike the classical one, contains sharp peaks corresponding to some specific scattering angles, that is connected with the diffraction of the incident plane wave onto the periodically distributed crystal atomic strings. It is shown that the value of the scattering cross-section in the peaks varies periodically with the change of the target thickness. We note that this must lead to a new interference effect in radiation that is connected with the rearrangement of incident wave packet in transitional area of crystal thicknesses.
Electron-helium scattering in Debye plasmas
International Nuclear Information System (INIS)
Zammit, Mark C.; Fursa, Dmitry V.; Bray, Igor; Janev, R. K.
2011-01-01
Electron-helium scattering in weakly coupled hot-dense (Debye) plasma has been investigated using the convergent close-coupling method. The Yukawa-type Debye-Hueckel potential has been used to describe plasma Coulomb screening effects. Benchmark results are presented for momentum transfer cross sections, excitation, ionization, and total cross sections for scattering from the ground and metastable states of helium. Calculations cover the entire energy range up to 1000 eV for the no screening case and various Debye lengths (5-100 a 0 ). We find that as the screening interaction increases, the excitation and total cross sections decrease, while the total ionization cross sections increase.
Quasielastic electron scattering from 40Ca
International Nuclear Information System (INIS)
Williamson, C.F.; Yates, T.C.; Schmitt, W.M.; Osborn, M.; Deady, M.; Zimmerman, P.D.; Blatchley, C.C.; Seth, K.K.; Sarmiento, M.; Parker, B.; Jin, Y.; Wright, L.E.; Onley, D.S.
1997-01-01
Differential cross sections for quasielastic electron scattering on 40 Ca have been measured at laboratory scattering angles of 45.5 degree, 90 degree, and 140 degree with bombarding energies ranging from 130 to 840 MeV. Transverse and longitudinal response functions have been extracted for momentum transfers from 300 to 500 MeV/c. Contrary to some previously reported results, the total observed longitudinal strength agrees with the relativistic Fermi gas prediction to within ±18%. copyright 1997 The American Physical Society
Low energy electron scattering from fuels
International Nuclear Information System (INIS)
Lopes, M. Cristina A.; Silva, Daniel G.M.; Coelho, Rafael F.; Duque, Humberto V.; Santos, Rodrigo R. dos; Ribeiro, Thiago M.
2011-01-01
Full text. Accurate and precise values of absolute total cross section (TCS) represent important information in many scientific and technological applications. In our case, for example, we are motivated to provide such information for electron-fuel collision processes which are specifically relevant to modeling spark ignition in alcohol-fuelled internal combustion engines. Many electron scattering TCS measurements are presently available for a diverse range of atomic and molecular targets. However, lack of data for important bio-molecular targets still remains. Disagreements between the available TCS data for the alcohols have prompted several studies of electron scattering collision of slow electrons with these molecules which are currently important in applications as bio- fuels. This relevance, which has attracted much attention, has been one of the subjects of a recent collaboration between experimental and theoretical groups in the USA and Brazil. Recently this collaboration reported first measurements and calculations of differential cross sections for elastic low-energy (rotationally unresolved) electron scattering by several primary alcohols. In this work we address methanol and ethanol TCSs at low energy range and report additional studies of resonant structure in ethanol using the detection of metastable states produced by electron impact excitation with high energy resolution. We have recently constructed a TCS apparatus in our laboratory at Universidade Federal de Juiz de Fora, Brazil, based on the well-known linear transmission technique. The experimental setup is based on the measurement of the attenuation of a collimated electron beam through a gas cell containing the atoms or molecules to be studied at a given pressure. It consists essentially of an electron gun, a gas cell and an electron energy analyzer composed of an array of decelerating electrostatic lenses, a cylindrical dispersive 127o analyzer and a Faraday cup. To our knowledge, there exist
Low energy electron scattering from fuels
Energy Technology Data Exchange (ETDEWEB)
Lopes, M. Cristina A.; Silva, Daniel G.M.; Coelho, Rafael F.; Duque, Humberto V.; Santos, Rodrigo R. dos; Ribeiro, Thiago M. [Universidade Federal de Juiz de Fora (UFJF), MG (Brazil). Dept. de Fisica; Yates, Brent; Hong, Ling; Khakoo, Murtadha A. [California State University at Fullerton, CA (US). Physics Department; Bettega, Marcio H.F. [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Fisica; Costa, Romarly F. da [Universidade Federal do ABC (UFABC), Santo Andre, SP (Brazil). Centro de Ciencias Naturais e Humanas; Lima, Marco A.P. [Laboratorio Nacional de Ciencia e Tecnologia do Bioetanol (CTBE/CNPEM), Campinas, SP (Brazil)
2011-07-01
Full text. Accurate and precise values of absolute total cross section (TCS) represent important information in many scientific and technological applications. In our case, for example, we are motivated to provide such information for electron-fuel collision processes which are specifically relevant to modeling spark ignition in alcohol-fuelled internal combustion engines. Many electron scattering TCS measurements are presently available for a diverse range of atomic and molecular targets. However, lack of data for important bio-molecular targets still remains. Disagreements between the available TCS data for the alcohols have prompted several studies of electron scattering collision of slow electrons with these molecules which are currently important in applications as bio- fuels. This relevance, which has attracted much attention, has been one of the subjects of a recent collaboration between experimental and theoretical groups in the USA and Brazil. Recently this collaboration reported first measurements and calculations of differential cross sections for elastic low-energy (rotationally unresolved) electron scattering by several primary alcohols. In this work we address methanol and ethanol TCSs at low energy range and report additional studies of resonant structure in ethanol using the detection of metastable states produced by electron impact excitation with high energy resolution. We have recently constructed a TCS apparatus in our laboratory at Universidade Federal de Juiz de Fora, Brazil, based on the well-known linear transmission technique. The experimental setup is based on the measurement of the attenuation of a collimated electron beam through a gas cell containing the atoms or molecules to be studied at a given pressure. It consists essentially of an electron gun, a gas cell and an electron energy analyzer composed of an array of decelerating electrostatic lenses, a cylindrical dispersive 127o analyzer and a Faraday cup. To our knowledge, there exist
International Nuclear Information System (INIS)
Howell, C.R.; Tornow, W.; Murphy, K.; Pfuetzner, H.G.; Roberts, M.L.; Li, A.; Felsher, P.D.; Walter, R.L.; Slaus, I.; Treado, P.A.; Koike, Y.
1987-01-01
High-accuracy analyzing-power A y (θ) data for n-d elastic scattering at 12 MeV have been measured using the polarized-neutron facilities at the Triangle Universities Nuclear Laboratory (TUNL). The present data have been combined with previous n-d measurements at 10, 12, and 14.1 MeV to form the highest-accuracy A y (θ) data set for n-d elastic scattering below 20 MeV. These data are compared to recent Faddeev-based neutron-deuteron (n-d) calculations which use the Paris and Bonn equivalent separable potentials PEST and BEST, as well as Doleschall's representation of the P- and D-wave nucleon-nucleon interactions. None of these models adequately describe the data in the angular region around the maximum of A y (θ). Possible reasons for the discrepancies are discussed. The sensitivity of the present Faddeev-based calculations to various angular momentum components of the nucleon-nucleon interaction are examined. (Auth.)
Incoherent imaging using dynamically scattered coherent electrons
International Nuclear Information System (INIS)
Nellist, P.D.; Pennycook, S.J.
1999-01-01
We use a Bloch wave approach to show that, even for coherent dynamical scattering from a stationary lattice with no absorption, annular dark-field imaging in a scanning transmission electron microscope gives a direct incoherent structure image of the atomic-column positions of a zone-axis-aligned crystal. Although many Bloch waves may be excited by the probe, the detector provides a filtering effect so that the 1s-type bound states are found to dominate the image contrast for typical experimental conditions. We also find that the column intensity is related to the transverse kinetic energy of the 1s states, which gives atomic number, Z, contrast. The additional effects of phonon scattering are discussed, in particular the reasons why phonon scattering is not a prerequisite for transverse incoherence. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)
Electromagnetic Structure of the Deuteron
International Nuclear Information System (INIS)
Franz Gross
2002-01-01
Recent high energy measurements of elastic ed scattering support the use of a relativistic theory based on an accurate description of the NN channel, but theory needed for an understanding of the high energy deuteron photodisintegration cross sections and polarized observables is not yet mature
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
Electron scattering and collective excitations in nuclei
International Nuclear Information System (INIS)
Goutte, D.
1989-01-01
Nuclear collective degrees of freedom are investigated through the study of the radial dependance of their wave function. Inelastic electron scattering is shown to be the appropriate tool to extract such a detailed information. Some recent results on spherical as well as deformed nuclei are discussed and the most recent extensions to the mean field approach are compared to these data in order to clarify the present status of our understanding of the dynamical properties of complex nuclei
Measurement of the Proton and Deuteron Spin Structure Functions G1 and G2
Energy Technology Data Exchange (ETDEWEB)
Tobias, Al
2003-04-02
The SLAC experiment E155 was a deep-inelastic scattering experiment that scattered polarized electrons off polarized proton and deuteron targets in the effort to measure precisely the proton and deuteron spin structure functions. The nucleon structure functions g{sub 1} and g{sub 2} are important quantities that help test our present models of nucleon structure. Such information can help quantify the constituent contributions to the nucleon spin. The structure functions g{sub 1}{sup p} and G{sub 1}{sup d} have been measured over the kinematic range 0.01 {le} x {le} 0.9 and 1 {le} Q{sup 2} {le} 40 GeV{sup 2} by scattering 48.4 GeV longitudinally polarized electrons off longitudinally polarized protons and deuterons. In addition, the structure functions g{sub 2}{sup p} and g{sub 2}{sup d} have been measured over the kinematic range 0.01 {le} x {le} 0.7 and 1 {le} Q{sup 2} {le} 17 GeV{sup 2} by scattering 38.8 GeV longitudinally polarized electrons off transversely polarized protons and deuterons. The measurements of g{sub 1} confirm the Bjorken sum rule and find the net quark polarization to be {Delta}{Sigma} = 0.23 {+-} 0.04 {+-} 0.6 while g{sub 2} is found to be consistent with the g{sub 2}{sup WW} model.
Electronic isotope shifts, muonic atoms, and electron scattering
International Nuclear Information System (INIS)
Shera, E.B.
1982-01-01
The roles of electronic isotope shift, muonic atom, and electron scattering experiments in studying the nuclear charge distribution are discussed in terms of the potentials of each probe. Barium isotope shift data are presented as an example of a combined muonic-optical analysis and the results are compared with droplet and IBA model predictions. A survey of muonic and (e,e) results is presented with emphasis on shell-structure related features
Thermal diffuse scattering in transmission electron microscopy
Energy Technology Data Exchange (ETDEWEB)
Forbes, B.D.; D' Alfonso, A.J. [School of Physics, University of Melbourne, Parkville, Victoria 3010 (Australia); Findlay, S.D. [School of Physics, Monash University, Victoria 3800 (Australia); Van Dyck, D. [EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); LeBeau, J.M. [North Carolina State University, Raleigh, NC 27695-7907 (United States); Stemmer, S. [Materials Department, University of California, Santa Barbara, CA 93106-5050 (United States); Allen, L.J., E-mail: lja@unimelb.edu.au [School of Physics, University of Melbourne, Parkville, Victoria 3010 (Australia)
2011-12-15
In conventional transmission electron microscopy, thermal scattering significantly affects the image contrast. It has been suggested that not accounting for this correctly is the main cause of the Stobbs factor, the ubiquitous, large contrast mismatch found between theory and experiment. In the case where a hard aperture is applied, we show that previous conclusions drawn from work using bright field scanning transmission electron microscopy and invoking the principle of reciprocity are reliable in the presence of thermal scattering. In the aperture-free case it has been suggested that even the most sophisticated mathematical models for thermal diffuse scattering lack in their numerical implementation, specifically that there may be issues in sampling, including that of the contrast transfer function of the objective lens. We show that these concerns can be satisfactorily overcome with modest computing resources; thermal scattering can be modelled accurately enough for the purpose of making quantitative comparison between simulation and experiment. Spatial incoherence of the source is also investigated. Neglect or inadequate handling of thermal scattering in simulation can have an appreciable effect on the predicted contrast and can be a significant contribution to the Stobbs factor problem. -- Highlights: Black-Right-Pointing-Pointer We determine the numerical requirements for accurate simulation of TDS in CTEM. Black-Right-Pointing-Pointer TDS can be simulated to high precision using the Born-Oppenheimer model. Black-Right-Pointing-Pointer Such calculations establish the contribution of TDS to the Stobbs factor problem. Black-Right-Pointing-Pointer Treating spatial incoherence using envelope functions increases image contrast. Black-Right-Pointing-Pointer Rigorous treatment of spatial incoherence significantly reduces image contrast.
Electron scattering cross sections pertinent to electron microscopy
International Nuclear Information System (INIS)
Inokuti, M.
1978-01-01
Some elements of the physics that determine cross sections are discussed, and various sources of data are indicated that should be useful for analytical microscopy. Atoms, molecules, and to some extent, solids are considered. Inelastic and elastic scattering of electrons and some solid-state effects are treated. 30 references
Electron distortion effects in quasi-eleastic electron scattering
International Nuclear Information System (INIS)
Jin, Yanhe.
1991-03-01
This report discusses the following topics: dirac single particle shell model; dirac free states in Coulomb and optical potentials; deep inelastic electron scattering; plane wave born approximation and Rosenbluth separation; analysis of the 40 Ca(e,e') experimental data; and analysis of the exclusive (e,e'p) experimental data
Future of Electron Scattering and Diffraction
Energy Technology Data Exchange (ETDEWEB)
Hall, Ernest [GE Global Research, Niskayuna, New York (United States); Stemmer, Susanne [Univ. of California, Santa Barbara, CA (United States); Zheng, Haimei [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Zhu, Yimei [Brookhaven National Lab. (BNL), Upton, NY (United States); Maracas, George [Dept. of Energy (DOE), Washington DC (United States). Office of Science
2014-02-25
The ability to correlate the atomic- and nanoscale-structure of condensed matter with physical properties (e.g., mechanical, electrical, catalytic, and optical) and functionality forms the core of many disciplines. Directing and controlling materials at the quantum-, atomic-, and molecular-levels creates enormous challenges and opportunities across a wide spectrum of critical technologies, including those involving the generation and use of energy. The workshop identified next generation electron scattering and diffraction instruments that are uniquely positioned to address these grand challenges. The workshop participants identified four key areas where the next generation of such instrumentation would have major impact: A – Multidimensional Visualization of Real Materials B – Atomic-scale Molecular Processes C – Photonic Control of Emergence in Quantum Materials D – Evolving Interfaces, Nucleation, and Mass Transport Real materials are comprised of complex three-dimensional arrangements of atoms and defects that directly determine their potential for energy applications. Understanding real materials requires new capabilities for three-dimensional atomic scale tomography and spectroscopy of atomic and electronic structures with unprecedented sensitivity, and with simultaneous spatial and energy resolution. Many molecules are able to selectively and efficiently convert sunlight into other forms of energy, like heat and electric current, or store it in altered chemical bonds. Understanding and controlling such process at the atomic scale require unprecedented time resolution. One of the grand challenges in condensed matter physics is to understand, and ultimately control, emergent phenomena in novel quantum materials that necessitate developing a new generation of instruments that probe the interplay among spin, charge, orbital, and lattice degrees of freedom with intrinsic time- and length-scale resolutions. Molecules and soft matter require imaging and
Electron scattering and transport in liquid argon
International Nuclear Information System (INIS)
Boyle, G. J.; Cocks, D. G.; White, R. D.; McEachran, R. P.
2015-01-01
The transport of excess electrons in liquid argon driven out of equilibrium by an applied electric field is revisited using a multi-term solution of Boltzmann’s equation together with ab initio liquid phase cross-sections calculated using the Dirac-Fock scattering equations. The calculation of liquid phase cross-sections extends previous treatments to consider multipole polarisabilities and a non-local treatment of exchange, while the accuracy of the electron-argon potential is validated through comparison of the calculated gas phase cross-sections with experiment. The results presented highlight the inadequacy of local treatments of exchange that are commonly used in liquid and cluster phase cross-section calculations. The multi-term Boltzmann equation framework accounting for coherent scattering enables the inclusion of the full anisotropy in the differential cross-section arising from the interaction and the structure factor, without an a priori assumption of quasi-isotropy in the velocity distribution function. The model, which contains no free parameters and accounts for both coherent scattering and liquid phase screening effects, was found to reproduce well the experimental drift velocities and characteristic energies
Electron scattering and transport in liquid argon
Energy Technology Data Exchange (ETDEWEB)
Boyle, G. J.; Cocks, D. G.; White, R. D. [College of Science, Technology and Engineering, James Cook University, Townsville 4810 (Australia); McEachran, R. P. [Research School of Physical Sciences and Engineering, Australian National University, Canberra ACT 0200 (Australia)
2015-04-21
The transport of excess electrons in liquid argon driven out of equilibrium by an applied electric field is revisited using a multi-term solution of Boltzmann’s equation together with ab initio liquid phase cross-sections calculated using the Dirac-Fock scattering equations. The calculation of liquid phase cross-sections extends previous treatments to consider multipole polarisabilities and a non-local treatment of exchange, while the accuracy of the electron-argon potential is validated through comparison of the calculated gas phase cross-sections with experiment. The results presented highlight the inadequacy of local treatments of exchange that are commonly used in liquid and cluster phase cross-section calculations. The multi-term Boltzmann equation framework accounting for coherent scattering enables the inclusion of the full anisotropy in the differential cross-section arising from the interaction and the structure factor, without an a priori assumption of quasi-isotropy in the velocity distribution function. The model, which contains no free parameters and accounts for both coherent scattering and liquid phase screening effects, was found to reproduce well the experimental drift velocities and characteristic energies.
Boson structure functions from inelastic electron scattering
International Nuclear Information System (INIS)
De Jager, C.W.
1986-01-01
The even /sup 104-110/Pd isotopes and /sup 196/Pt have been investigated at NIKHEF-K by high-resolution inelastic electron scattering. A new IBA-2 calculation has been performed for the Pd isotopes, in which the ratio of the proton and neutron coupling constants is taken from pion scattering. One set of boson structure functions sufficed for the description of the first and second E2-excitations in all Pd isotopes. The data showed no sensitivity for different structure functions for proton and neutron bosons. A preliminary analysis of a number of negative parity states (3/sup -/,5/sup -/ and 7/sup -/), observed in /sup 196/Pt, was performed through the introduction of an f-boson. The first E4-excitation in the palladium isotopes can be reasonably described with a β-structure function, but all other E4-excitations require the introduction of g-boson admixtures
Electron-atom scattering at intermediate energies
International Nuclear Information System (INIS)
Kingston, A.E.; Walters, H.R.J.
1982-01-01
The problems of intermediate energy scattering are approached from the low and high energy ends. At low intermediate energies difficulties associated with the use of pseudostates and correlation terms are discussed, special consideration being given to nonphysical pseudoresonances. Perturbation methods appropriate to high intermediate energies are described and attempts to extend these high energy approximations down to low intermediate energies are studied. It is shown how the importance of electron exchange effects develops with decreasing energy. The problem of assessing the 'effective completeness' of pseudostate sets at intermediate energies is mentioned and an instructive analysis of a 2p pseudostate approximation to elastic e - -H scattering is given. It is suggested that at low energies the Pauli Exclusion Principle can act to hide short range defects in pseudostate approximations. (author)
Electron--molecule scattering in momentum space
International Nuclear Information System (INIS)
Ritchie, B.
1979-01-01
We examine the Fourier transform of the Schroedinger equation for electron--molecule scattering, treated as potential scattering from a multicenter distribution of charged fixed in space. When the angle theta between R,the internuclear vector of a diatomic target, and q, the momentum transfer, is held fixed during the collision, then the directions of incidence and scattering are fixed relative to R. The process is then described as having a dynamical dependence on the magnitude of q, q, from which the scattering angle is determined, and a parametric dependence on q's direction relative to R. This approximation is used routinely at high energies in the calculation of the Born amplitude. Fixed--nuclei coordinate--space studies suggest that this approximation can be extended to low energies, provided the amplitude is taken from the solution of the integral equation of momentum space rather than from its inhomogeneity, proportional to the Born amplitude. We constrain R to be in the same direction relative to q', a virtual momentum transfer belonging to the kernel, as it is to q.Calculations are performed for the e, H 2 scattering in the static approximation, and cross sections averaged over theta/sub R/ are shown to be in good agreement with cross sections calculated by use of coupled spherical and coupled spheroidal partial wave theories. The angular distribution in the static approximation is also calculated at an incident energy close to 7 eV, where exchange is relatively unimportant. This result is in reasonably good agreement with that of R matrix theory in the static--exchange approximation. The extension of the theory to treat exchange is formulated and discussed. Also its extension to treat more complicated molecular targets is discussed
Advances in positron and electron scattering*
Limão-Vieira, Paulo; García, Gustavo; Krishnakumar, E.; Petrović, Zoran; Sullivan, James; Tanuma, Hajime
2016-10-01
The topical issue on Advances in Positron and Electron Scattering" combines contributions from POSMOL 2015 together with others devoted to celebrate the unprecedented scientific careers of our loyal colleagues and trusted friends Steve Buckman (Australian National University, Australia) and Michael Allan (University of Fribourg, Switzerland) on the occasion of their retirements. POSMOL 2015, the XVIII International Workshop on Low-Energy Positron and Positronium Physics and the XIX International Symposium on Electron-Molecule Collisions and Swarms, was held at Universidade NOVA de Lisboa, Lisboa, Portugal, from 17-20 July 2015. The international workshop and symposium allowed to achieve a very privileged forum of sharing and developing our scientific expertise on current aspects of positron, positronium and antiproton interactions with electrons, atoms, molecules and solid surfaces, and related topics, as well as electron interactions with molecules in both gaseous and condensed phases. Particular topics include studies of electron interactions with biomolecules, electron induced surface chemistry and the study of plasma processes. Recent developments in the study of swarms are also fully addressed.
Electron scattering and few nucleon systems
International Nuclear Information System (INIS)
Frois, B.
1983-08-01
Recent result obtained by electron scattering in the few-nucleon systems (A 3 He charge and magnetic form factors are discussed. New theoretical results indicate that three body forces improve considerably the saturation properties of 3 He, 4 He and nuclear matter, but are not able to reconcile experiment and theory for the charge form factors of 3 He and 4 He. Calculations of meson exchange effects with different theoretical approaches bring the theory into reasonable agreement with the experimental charge and magnetic form factor fo 3 He. Recent results of the measurements of the two and three body break-up of 3 He are discussed
Model potential for electron scattering from rubidium
Energy Technology Data Exchange (ETDEWEB)
Gien, T.E. (Memorial Univ. of Newfoundland, St. John' s, NF (Canada). Dept. of Physics)
1992-11-28
An analytic model potential for the e[sup -]-Rb[sup +] system is generated from experimental data, using an iteration method. The potential obtained can reproduce rather accurately the energy levels of rubidium. We employed it in the calculation of elastic differential cross sections for electron (and positron) scatterings from rubidium in the conventional Glauber approximation. The differential cross sections calculated in the model potential approach are compared to those in the frozen-core approach, employing either the Clementi-Roetti or the Szasz-McGinn wavefunctions. The core correlation and polarization effects are found to significantly affect the cross section results. (author).
Model potential for electron scattering from rubidium
International Nuclear Information System (INIS)
Gien, T.E.
1992-01-01
An analytic model potential for the e - -Rb + system is generated from experimental data, using an iteration method. The potential obtained can reproduce rather accurately the energy levels of rubidium. We employed it in the calculation of elastic differential cross sections for electron (and positron) scatterings from rubidium in the conventional Glauber approximation. The differential cross sections calculated in the model potential approach are compared to those in the frozen-core approach, employing either the Clementi-Roetti or the Szasz-McGinn wavefunctions. The core correlation and polarization effects are found to significantly affect the cross section results. (author)
Hadron production from $\\mu-Deuteron$ scattering at $\\sqrt{s}=17 GeV$ at COMPASS
Morreale, Astrid
2011-01-01
Hadrons proceeding from quasi-real photo-production are one of the many probes accesible at the Common Muon Proton Apparatus for Structure and Spectroscopy (COMPASS) at CERN. These hadrons provide information on the scattering between photon and partons through $\\gamma$-gluon($g$) direct channels as well as $q-g$ resolved processes. Comparisons of unpolarized differential cross section measurements to next-to-leading order (NLO) pQCD calculations are essential to develop our understanding of proton-proton and lepton-nucleon scattering at varying center of mass energies. These measurements are important to asses the applicability of NLO pQCD in interpreting polarized processes. In this talk we will present the unidentified charged separated hadron cross-sections measured by the COMPASS experiment at center of mass energy of $\\sqrt{s}$ = 17 $GeV$, low $Q^{2}$ (Q$^{2}$ 1.0 $GeV/c$.)
Alexakhin, V.Yu.; Alexeev, G.D.; Amoroso, A.; Badelek, B.; Balestra, F.; Ball, J.; Baum, G.; Bedfer, Y.; Berglund, P.; Bernet, C.; Bertini, R.; Birsa, R.; Bisplinghoff, J.; Bradamante, F.; Bravar, A.; Bressan, A.; Burtin, E.; Bussa, M.P.; Cerini, L.; Chapiro, A.; Cicuttin, A.; Colantoni, M.; Colavita, A.A.; Costa, S.; Crespo, M.L.; d'Hose, N.; Dalla Torre, S.; Dasgupta, S.S.; De Masi, R.; Dedek, N.; Denisov, O.Yu.; Dhara, L.; Diaz Kavka, V.; Dolgopolov, A.V.; Donskov, S.V.; Dorofeev, V.A.; Doshita, N.; Duic, V.; Dunnweber, W.; Efremov, A.; Ehlers, J.; Eversheim, P.D.; Eyrich, W.; Fabro, M.; Faessler, M.; Fauland, P.; Ferrero, A.; Ferrero, L.; Finger, M.; Fischer, H.; Franz, J.; Friedrich, J.M.; Frolov, V.; Fuchs, U.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.P.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gobbo, B.; Goertz, S.; Grajek, O.A.; Grasso, A.; Grube, B.; Grunemaier, A.; Gustafsson, K.; Hannappel, J.; von Harrach, D.; Hasegawa, T.; Hedicke, S.; Heinsius, F.H.; Hinterberger, F.; von Hodenberg, M.; Horikawa, N.; Horikawa, S.; Ijaduola, R.B.; Ilgner, C.; Ishimoto, S.; Iwata, T.; Jahn, R.; Janata, A.; Joosten, R.; Jouravlev, N.I.; Kabuss, E.; Kalinnikov, V.; Kang, D.; Karstens, F.; Kastaun, W.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu.A.; Kisselev, Yu.; Klein, F.; Koivuniemi, J.H.; Kolosov, V.N.; Komissarov, E.V.; Kondo, K.; Konigsmann, K.; Konoplyannikov, A.K.; Konorov, I.; Konstantinov, V.F.; Korentchenko, A.S.; Korzenev, A.; Kotzinian, A.M.; Koutchinski, N.A.; Kowalik, K.; Kravchuk, N.P.; Krivokhizhin, G.V.; Kroumchtein, Z.V.; Kuhn, R.; Kunne, F.; Kurek, K.; Lamanna, M.; Le Goff, J.M.; Leberig, M.; Lichtenstadt, J.; Maggiora, A.; Maggiora, M.; Magnon, A.; Mallot, G.K.; Manuilov, I.V.; Marchand, C.; Marroncle, J.; Martin, A.; Marzec, J.; Matsuda, T.; Maximov, A.N.; Medved, K.S.; Meyer, W.; Mielech, A.; Mikhailov, Yu.V.; Moinester, M.A.; Nahle, O.; Nassalski, J.; Neyret, D.P.; Nikolaenko, V.I.; Nozdrin, A.A.; Obraztsov, V.F.; Olshevsky, A.G.; Ostrick, M.; Padee, A.; Pagano, P.; Panebianco, S.; Panzieri, D.; Paul, S.; Pereira, H.D.; Peshekhonov, D.V.; Peshekhonov, V.D.; Piragino, G.; Platchkov, S.; Platzer, K.; Pochodzalla, J.; Polyakov, V.A.; Popov, A.A.; Pretz, J.; Rebourgeard, P.C.; Reicherz, G.; Reymann, J.; Rozhdestvensky, A.M.; Rondio, E.; Sadovski, A.B.; Saller, E.; Samoylenko, V.D.; Sandacz, A.; Sans, M.; Sapozhnikov, M.G.; Savin, I.A.; Schiavon, P.; Schmidt, T.; Schmitt, H.; Schmitt, L.; Shishkin, A.A.; Siebert, H.; Sinha, L.; Sissakian, A.N.; Skachkova, A.; Slunecka, M.; Smirnov, G.I.; Sugonyaev, V.P.; Stinzing, F.; Sulej, R.; Takabayashi, N.; Tchalishev, V.V.; Tessarotto, F.; Teufel, A.; Thers, D.; Tkatchev, L.G.; Toeda, T.; Tretyak, V.I.; Trousov, S.; Vlassov, N.V.; Webb, R.; Weise, E.; Wiesmann, M.; Windmolders, R.; Wirth, S.; Wislicki, W.; Zanetti, A.M.; Zaremba, K.; Zhao, J.; Ziegler, R.; Zvyagin, A.
2005-01-01
First measurements of the Collins and Sivers asymmetries of charged hadrons produced in deep-inelastic scattering of muons on a transversely polarized 6-LiD target are presented. The data were taken in 2002 with the COMPASS spectrometer using the muon beam of the CERN SPS at 160 GeV/c. The Collins asymmetry turns out to be compatible with zero, as does the measured Sivers asymmetry within the present statistical errors.
Study of nuclei by electron scattering
International Nuclear Information System (INIS)
Torizuka, Yoshiharu; Saito, Teijiro; Ito, Kohei; Terasawa, Tatsuo; Hosoyama, Kenji.
1974-01-01
It is urgently required to clarify the physical meaning of the quasi-elastic scattering associated with the background, in order to develop rapidly the study of giant resonance. The experimental works performed in the present term aimed at the synthetic understanding of both giant resonance and quasi-elastic scattering, and presented the possibility of the separability of giant resonance from quasi-elastic scattering. The object of this experiment was to measure higher order multi-pole moment of 51 V by using relatively high energy electron beam. Targets of chemically pure 51 V had thickness of 68.2 or 100.5 mg/cm 2 . The measurement was made at the position where scattering angle was 155 0 . The state of M7 can be well explained by the model with (fsub(7/2)) 3 coordination. This may be because the nuclei with stretched configuration such as 51 V do not have any contribution of orbital motion, but have the contribution of eigen magnetic moment to the highest multiplicity. States of M3 and M5 are a little complicated. Since in the experimental equipment used, the contribution of charge distribution was so large, that it was difficult to make the precision measurement of M3 and M5. In 51 V, however, it can be considered that M3 and M5 decreased by the contribution of 2Psub(3/2) and 1fsub(5/2). On the other hand, there is no contribution from these energy states to M7. (Tai, I.)
Inelastic electron scattering from a moving nucleon
Energy Technology Data Exchange (ETDEWEB)
Kuhn, S.E. [Old Dominion Univ., Norfolk, VA (United States); Griffioen, K. [College of William and Mary, Williamsburg, VA (United States)
1994-04-01
The authors propose to measure inelastically scattered electrons in coincidence with spectator protons emitted backwards relative to the virtual photon direction in the reaction d(e, e{prime}p{sub s})X. In a simple spectator model, the backward proton has equal and opposite momentum to the neutron before it is struck, allowing the authors to study the dependence on kinematics and off-shell behaviour of the electron-nucleon inelastic cross section. If the photon couples to a quark in a 6-quark bag, a different dependence of the cross section on the kinematic variables (x, Q{sup 2}, and p{sub s}) can be observed. This proposed experiment requires large acceptance and beam energies above 6 GeV. It is ideally suited for the CEBAF Large Acceptance Spectrometer (CLAS).
Parity violation in polarized electron scattering
International Nuclear Information System (INIS)
Prescott, C.Y.
1980-10-01
The weak forces are responsible for the decay of radioactive nuclei, and it was in these decay processes where parity non-conservation was first observed. Beta decay occurs through emission of e + or e - particles, indicating that the weak force can carry charge of both signs, and it was natural to speculate on the existence of a neutral component of the weak force. Even though weak neutral forces had not been observed it was conjectured that a neutral component of weak decay could exist, and Zel'dovich in 1957 suggested that parity violating effects may be observable in electron scattering and in atomic spectra. More than twenty years have passed since the early conjectures, and a great deal has been learned. Progress in quantum field theory led to the development of the SU(2) x U(1) gauge theory of weak and electromagnetic interactions and provided a renormalizable theory with a minimum of additional assumptions. Gauge theories predicted the existence of a new force, the neutral current interaction. This new interaction was first seen in 1973 in the Gargamelle bubble chamber at CERN. Today the neutral currents are accepted as well established, and it is the details of the neutral current structure that occupy attention. In particular the role that electrons play cannot be tested readily in neutrino beams (recent neutrino-electron scattering experiments are, however, rapidly improving this situation) and therefore interest in electron-hadron neutral current effects has been high. Parity violation is a unique signature of weak currents, and measurements of its size are a particularly important and sensitive means for determining the neutral current structure
Compton scattering on the proton, neutron, and deuteron in chiral perturbation theory to O(Q{sup 4})
Energy Technology Data Exchange (ETDEWEB)
S.R. Beane; M. Malheiro; J.A. McGovern; D.R. Phillips; U. van Kolck
2004-03-01
We study Compton scattering in systems with A=1 and 2 using chiral perturbation theory up to fourth order. For the proton we fit the two undetermined parameters in the O(Q{sup 4}) {gamma}p amplitude of McGovern to experimental data in the region {omega}, {radical}|t| {le} 180 MeV, obtaining a {chi}{sup 2}/d.o.f. of 133/113. This yields a model-independent extraction of proton polarizabilities based solely on low-energy data: {alpha}{sub p} = (12.1 {+-} 1.1 (stat.)){sub -0.5}{sup +0.5} (theory) and {beta}{sub p} = (3.4 {+-} 1.1 (stat.)){sub -0.1}{sup +0.1} (theory), both in units of 10{sup -4} fm{sup 3}. We also compute Compton scattering on deuterium to O(Q{sup 4}). The {gamma}d amplitude is a sum of one- and two-nucleon mechanisms, and contains two undetermined parameters, which are related to the isoscalar nucleon polarizabilities. We fit data points from three recent {gamma}d scattering experiments with a {chi}{sup 2}/d.o.f. = 26.3/20, and find {alpha}{sub N} = 8.9 {+-} 1.5 (stat.){sub -0.9}{sup +4.7} (theory) and {beta}{sub N} = 2.2 {+-} 1.5 (stat.){sub -0.9}{sup +1.2} (theory), again in units of 10{sup -4} fm{sup 3}.
Implementation of electron and deuteron accelerators in medicine, science and industry in Belarus
International Nuclear Information System (INIS)
Chigrinov, S.; Salnikov, L.
2001-01-01
Full text: Research in the field of radiation chemistry, studying the peculiarities of interaction of ionizing irradiation with polymer materials, application of studying for production of medicinal preparations, sterilization of medical products and so on was started in Belarus in the late 60s on the basis of Co-60 source, 400 kCi and are being continued from 1993 with using linear electron accelerator installed at the Radiation Physics and Chemistry Problems Institute. The nominal average beam power is 10 kW with electron energy 10 MeV. The accelerators are equipped with a conveyer with the regulator velocity. The electron scheme for the conveyer's control is applied to carry boxes with the sizes of 45x75 cm 2 to the electron accelerator with the velocity from 0.5 cm/s up to 5.0 cm/s. This industrial type facility allows to carry out investigations not only in the field of radiation chemistry, but also in medicine, industry and agriculture. Till today the only facility in Belarus where the radiation treatment of foodstuffs, medical herbs, sterilization of different types of medical devices, pharmaceuticals and raw materials, wound dressing, some food products are performed in a commercial scale. The Ministry of Health of the Republic has given permission for radiation treatment of the following food products: lactose, egg powder, spices, gelatin, meat of poultry, medical herbs. For radiation sterilization of medical devices and for radiation treatment of solid pharmaceuticals the dose 25 kGy was specified by the National State Authority.The project 'The Pilot-Scale Production of Hydrogel Dressings for Medical Purposes' (BYE/8/003) was approved within the framework of TC Program IAEA for 2001-2002 and was started in January. The project will be performed using electron accelerator. In the practice of radiation treatment EGS4 computer code is used to calculate the absorbed dose distribution in the boxes with the products to be irradiated. In 1998 the Institute
Electron-electron scattering in the Weinberg-Salam theory
International Nuclear Information System (INIS)
Hirashima, Hideharu
1988-01-01
The Weinberg theory is generally believed to have been established in recent years. At distances smaller than 10 -16 cm, the strength of weak interactions becomes almost equal to that of the electromagnetic interactions. The grand unified theories proposed so far are based on the idea that the coupling constants for the Abelian U(1) field, the non-Abelian SU(2) field and the non-Abelian SU(3) color field depend on momentum transfer, or distance. At distances smaller than 10 -29 cm, weak electromagnetic and strong interactions are assumed to become almost the same strength. The question here is whether nature has no new features in the vast range from 10 -16 cm (10 2 GeV) to 10 -29 cm (10 15 GeV) and whether the substructure of quark or lepton can be expected to be revealed at the next accelerator energy region. The Weinberger-Salam theory may lose its validity even in near future experiments. In any case, it must be overhauled from various aspects. From this point of view, by using the Weinberger-Salam theory, calculation of the differential cross section for elastic electron-electron scattering is re-examined to make clear the difference with the results of QED. In addition, as an example of experiments which could investigate the Weinberger-Salam theory more in detail, a short account is given of the elastic scattering of polarized electrons from a polarized electron target. (Nogami, K.)
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
Density-dependent electron scattering in photoexcited GaAs
DEFF Research Database (Denmark)
Mics, Zoltán; D'Angio, Andrea; Jensen, Søren A.
2013-01-01
—In a series of systematic optical pump - terahertz probe experiments we study the density-dependent electron scattering rate in photoexcited GaAs in a large range of carrier densities. The electron scattering time decreases by as much as a factor of 4, from 320 to 60 fs, as the electron density...
Measurement of the Deuteron Spin Structure Function g_1^d(x) for 1 (GeV/c)^2 < Q^2 < 40 (GeV/c)^2
E155 Collaboration
1999-01-01
New measurements are reported on the deuteron spin structure function g_1^d. These results were obtained from deep inelastic scattering of 48.3 GeV electrons on polarized deuterons in the kinematic range 0.01 < x < 0.9 and 1 < Q^2 < 40 (GeV/c)^2. These are the first high dose electron scattering data obtained using lithium deuteride (6Li2H) as the target material. Extrapolations of the data were performed to obtain moments of g_1^d, including Gamma_1^d, and the net quark polarization Delta Si...
Anthony , P.L.; Arnold , R.G.; Averett , T.; Band , H.R.; Berisso , M.C.; Borel , H.; Bosted , P.E.; Bultmann , S.L.; Buenerd , M.; Chupp , T.; Churchwell , S.; Court , G.R.; Crabb , D.; Day , D.; Decowski , P.
1999-01-01
New measurements are reported on the deuteron spin structure function g_1^d. These results were obtained from deep inelastic scattering of 48.3 GeV electrons on polarized deuterons in the kinematic range 0.01 < x < 0.9 and 1 < Q^2 < 40 (GeV/c)^2. These are the first high dose electron scattering data obtained using lithium deuteride (6Li2H) as the target material. Extrapolations of the data were performed to obtain moments of g_1^d, including Gamma_1^d, and the net quark polarization Delta Si...
Quark-Hadron Duality in Electron Scattering
Energy Technology Data Exchange (ETDEWEB)
Wally Melnitchouk; Rolf Ent; Cynthia Keppel
2004-08-01
The duality between partonic and hadronic descriptions of physical phenomena is one of the most remarkable features of strong interaction physics. A classic example of this is in electron-nucleon scattering, in which low-energy cross sections, when averaged over appropriate energy intervals, are found to exhibit the scaling behavior expected from perturbative QCD. We present a comprehensive review of data on structure functions in the resonance region, from which the global and local aspects of duality are quantified, including its flavor, spin and nuclear medium dependence. To interpret the experimental findings, we discuss various theoretical approaches which have been developed to understand the microscopic origins of quark-hadron duality in QCD. Examples from other reactions are used to place duality in a broader context, and future experimental and theoretical challenges are identified.
Exotic components of the deuteron wave function
International Nuclear Information System (INIS)
Kobushkin, A.P.; Syamtonov, A.I.
1996-01-01
Problems of quark exchange effects in cross sections and polarization observables of d p elastic backward scattering and (d, p) deuteron breakup at high and intermediate energy are considered. Theoretical predictions for new polarization observables of the d p elastic backward scattering are given [ru
Compton profiles by inelastic ion-electron scattering
International Nuclear Information System (INIS)
Boeckl, H.; Bell, F.
1983-01-01
It is shown that Compton profiles (CP) can be measured by inelastic ion-electron scattering. Within the impulse approximation the binary-encounter peak (BEP) reflects the CP of the target atom whereas the electron-loss peak (ELP) is given by projectile CP's. Evaluation of experimental data reveals that inelastic ion-electron scattering might be a promising method to supply inelastic electron or photon scattering for the determination of target CP's. The measurement of projectile CP's is unique to ion scattering since one gains knowledge about wave-function effects because of the high excitation degree of fast heavy-ion projectiles
International Nuclear Information System (INIS)
Peterson, G.A.
1981-08-01
Electron scattering experiments are in progress at the Bates Linear Accelerator in Middleton, Massachusetts. Both magnetic elastic and transverse inelastic scattering cross sections have been measured at 180 0 by the apparatus constructed and brought into operation in late 1977 by the University of Massachusetts. A liquid-nitrogen-cooled gas target is being used in a study of deuteron elastic magnetic scattering and electrodisintegration over a large energy range. A measurement of elastic magnetic and transverse inelastic scattering from 14 N has been started. Measurements of the elastic magnetic scattering from 13 C, 15 N, 27 Al, 29 Si, and 31 P have been completed. The data set on 15 N inelastic scattering are now complete and analysis of the data is in progress. A study of M8 transitions in 54 Fe and 60 Ni is nearing completion. Several papers are being written on these subjects. A measurement of the transverse quasi-elastic scattering from 56 Fe has been started. Planning for an experiment utilizing radioactive 14 C is underway. Large-basis shell model calculations pertaining to the above nuclei and others have been made. Theoretical calculations of exchange currents, nuclear convection currents, and other nuclear phenomena are in progress. Finally, considerations are being given to the design of an integrated storage-ring-experimental system
International Nuclear Information System (INIS)
Peterson, G.A.
1981-08-01
Electron scattering experiments are in progress at the Bates Linear Accelerator in Middleton, Massachusetts. Both magnetic elastic and transverse inelastic scattering cross sections have been measured at 180 0 by the apparatus constructed and brought into operation in late 1977 by the University of Massachusetts. A liquid-nitrogen-cooled gas target is being used in a study of deuteron elastic scattering and electrodisintegration over a large energy range. A measurement of elastic magnetic and transverse inelastic scattering from 14 N has been started. Measurements of the elastic magnetic scattering from 13 C, 15 N, 27 Al, 29 Si, and 31 P have been completed. The data set on 15 N inelastic scattering are now complete and analysis of the data is in progress. A study of M8 transitions in 54 Fe and 60 Ni is nearing completion. A measurement of the transverse quasielastic scattering from 56 Fe has been started. Planning for an experiment utilizing radioactive 14 C is underway. Large-basis shell model calculations pertaining to the above nuclei and others have been made. Theoretical calculations of exchange currents, nuclear convection currents, and other nuclear phenomena are in progress. Finally, considerations are being given to the design of an integrated storage-ring-experimental system
Compton scattering of photons from electrons bound in light elements
International Nuclear Information System (INIS)
Bergstrom, P.M. Jr.
1994-01-01
A brief introduction to the topic of Compton scattering from bound electrons is presented. The fundamental nature of this process in understanding quantum phenomena is reviewed. Methods for accurate theoretical evaluation of the Compton scattering cross section are presented. Examples are presented for scattering of several keV photons from helium
Some remarks on electron scattering in a laser field
International Nuclear Information System (INIS)
Ehlotzky, F.
1988-01-01
Potential scattering of electrons in a quantized radiation field is reconsidered. Some remarks are made on the validity of the Kroll-Watson scattering formula and on the close connection of this formula with the classical transition rate of scattering in a radiation field. (17 refs.)
Electron scattering with polarized targets at TESLA
International Nuclear Information System (INIS)
Anselmino, M.; Aschenauer, E.C.; Belostotski, S.
2000-11-01
Measurements of polarized electron-nucleon scattering can be realized at the TESLA linear collider facility with projected luminosities that are about two orders of magnitude higher than those expected of other experiments at comparable energies. Longitudinally polarized electrons, accelerated as a small fraction of the total current in the e + arm of TESLA, can be directed onto a solid state target that may be either longitudinally or transversely polarized. A large variety of polarized parton distribution and fragmentation functions can be determined with unprecedented accuracy, many of them for the first time. A main goal of the experiment is the precise measurement of the x- and Q 2 -dependence of the experimentally totally unknown quark transversity distributions that will complete the information on the nucleon's quark spin structure as relevant for high energy processes. Comparing their Q 2 -evolution to that of the corresponding helicity distributions constitutes an important precision test of the predictive power of QCD in the spin sector. Measuring transversity distributions and tensor charges allows access to the hitherto unmeasured chirally odd operators in QCD which are of great importance to understand the role of chiral symmetry. The possibilities of using unpolarized targets and of experiments with a real photon beam turn TESLA-N into a versatile next-generation facility at the intersection of particle and nuclear physics. (orig.)
Electron scattering studies by means of various nuclear models
International Nuclear Information System (INIS)
Essaniyazov, Sh.; Juraev, Sh.; Ismatov, E.I.
2006-01-01
Full text: Let us consider a general case of various interaction processes of electrons with nuclei. The study of the scattering o electrons of nuclei is the source of information on the structure of nuclei. At collision of fast electrons with nuclei, both elastic and inelastic scattering can be observed. Elastic scattering gives information on the sizes of nuclei, whereas the electrons inelastic scattering processes give important information on the dynamical properties of nuclei. In the first case, the characteristics of excited states, energy levels, their widths and others, and in the second case, momentum distribution of nucleons and other particles in nuclei are studied. Let us denote the momentum and the energy of the incident electron before and after the scattering as k and ε, and k' and ε', respectively. The angle between the vectors k and k' is denoted as θ. The scattering process is characterized by three parameters: k, k' and θ. However, it is convenient to introduce three other parameters instead of the indicated above. They are: energy ω ε - ε' and momentum q = k - k', transferred by electron at scattering, and the scattering angle θ. It is worth of mentioning the two reasons why the study of electron scattering is very effective tool to study the nuclear structure. First of all, the character of electron interaction with nucleus is a well-known electromagnetic interaction of electron with current and charge in nucleus. Secondly, this interaction is relatively weak (e 2 /ℎc) 2 = ω 2 is possible (since the photon mass is zero). In case of electrons, at fixed energy transfer ω various momentum transfer are possible. Therefore, at electron scattering study one can establish the dependence of the matrix elements of q, which are the Fourier-representations of the charge and current densities. Thus, it is possible to determine directly the spatial distribution of charge and current in nucleus. The inelastic scattering is accompanied by
Electron scattering studies of nitrogen dioxide
Energy Technology Data Exchange (ETDEWEB)
Gupta, Dhanoj; Naghma, Rahla [Department of Applied Physics, Indian School of Mines, Dhanbad 826004, Jharkhand (India); Vinodkumar, Minaxi [V. P. and R. P. T. P. Science College, Vallabh Vidyanagar 388120, Gujarat (India); Antony, Bobby, E-mail: bka.ism@gmail.com [Department of Applied Physics, Indian School of Mines, Dhanbad 826004, Jharkhand (India)
2013-12-15
Highlights: •Two quantum mechanical models used to find TCS for e-NO{sub 2} from 0.5 to 2000 eV. •R-matrix method at low energies (<15 eV) and SCOP at high energies (16 to 2000 eV). •Besides CS, R-matrix method predicts resonances and possibility of DEA formation. •SCOP formalism is used to find total inelastic and elastic CS at high energies. •Resonances detected at 1.33, 3 and 8.41 eV is associated with O{sup −} anion formation by DEA. -- Abstract: Present work reports total cross sections for e-NO{sub 2} scattering over an extensive range of impact energy from 0.5 eV to 2000 eV, through a composite formalism. The ab initio R-matrix method is employed for calculations up to 15 eV while the spherical complex optical potential formalism is used beyond that energy. The electronic excitation cross sections are computed from ground state X{sup 2}A{sub 1} to seven electronically allowed excited states {sup 2}B{sub 1}, {sup 2}B{sub 2}, {sup 2}A{sub 2}, {sup 4}A{sub 2}, {sup 4}B{sub 2}, {sup 4}A{sub 1}, {sup 4}A{sub 1} and {sup 4}B{sub 1}. The eigenphase diagrams presented here reproduces the resonances identified earlier. The structures detected at 1.33, 3 and 8.41 eV can be associated with the observed O{sup −} anion formation through dissociative electron attachment process.
No surprise in the first Born approximation for electron scattering
International Nuclear Information System (INIS)
Lentzen, M.
2014-01-01
In a recent article it is argued that the far-field expansion of electron scattering, a pillar of electron diffraction theory, is wrong (Treacy and Van Dyck, 2012 [1]). It is further argued that in the first Born approximation of electron scattering the intensity of the electron wave is not conserved to first order in the scattering potential. Thus a “mystery of the missing phase” is investigated, and the supposed flaw in scattering theory is seeked to be resolved by postulating a standing spherical electron wave (Treacy and Van Dyck, 2012 [1]). In this work we show, however, that these theses are wrong. A review of the essential parts of scattering theory with careful checks of the underlying assumptions and limitations for high-energy electron scattering yields: (1) the traditional form of the far-field expansion, comprising a propagating spherical wave, is correct; (2) there is no room for a missing phase; (3) in the first Born approximation the intensity of the scattered wave is conserved to first order in the scattering potential. The various features of high-energy electron scattering are illustrated by wave-mechanical calculations for an explicit target model, a Gaussian phase object, and for a Si atom, considering the geometric conditions in high-resolution transmission electron microscopy. - Highlights: Treacy and Van Dyck (2012) argue that the far-field expansion of electron scattering is wrong. The chief theses of that former work are wrong. There is no room for the missing phase proposed by Treacy and Van Dyck. There is no violation of the intensity conservation to first order in the scattering potential. Calculations for a phase object and an atomic target confirm traditional scattering theory
Spin dependence in superelastic electron scattering from Na(3P)
International Nuclear Information System (INIS)
McClelland, J.J.; Kelley, M.H.; Celotta, R.J.
1985-01-01
Measurements are presented of spin asymmetries for superelastic scattering of 10-eV spin polarized electrons from the excited Na(3P/sub 3/2/) state created by linearly polarized laser optical pumping. Asymmetries as large as 16% are observed in scattering from a state which is not spin-polarized. Results are shown both as a function of scattering angle with fixed laser polarization direction, and as a function of the laser polarization direction at a fixed scattering angle
Role of electron-electron scattering on spin transport in single layer graphene
Directory of Open Access Journals (Sweden)
Bahniman Ghosh
2014-01-01
Full Text Available In this work, the effect of electron-electron scattering on spin transport in single layer graphene is studied using semi-classical Monte Carlo simulation. The D’yakonov-P’erel mechanism is considered for spin relaxation. It is found that electron-electron scattering causes spin relaxation length to decrease by 35% at 300 K. The reason for this decrease in spin relaxation length is that the ensemble spin is modified upon an e-e collision and also e-e scattering rate is greater than phonon scattering rate at room temperature, which causes change in spin relaxation profile due to electron-electron scattering.
Inelastic electron scattering at low momentum transfer
International Nuclear Information System (INIS)
Richter, A.
1979-01-01
Recent advances of high energy resolution (ΔE approx. 30 keV FWHM) inelastic electron scattering at low momentum transfer (q -1 ) using selected experimental data from the Darmstadt electron linear accelerator are discussed. Strong emphasis is given to a comparison of the data with theoretical nuclear model predictions. Of the low multipolarity electric transitions investigated, as examples only E1 transitions to unnatural parity states in 11 B and E2 transitions of the very fragmented isoscalar quadrupole giant resonance in 208 Pb are considered. In 11 B the role of the Os hole in the configuration of the 1/2 + , 3/2 + and 5/2 + states is quantitatively determined via an interference mechanism in the transition probability. By comparison of the high resolution data with RPA calculations the E2 EWSR in 208 Pb is found to be much less exhausted than anticipated from previous medium energy resolution (e,e) and hadron scattering experiments. In the case of M1 transitions it is shown that the simplest idealized independent particle shell-model prediction breaks down badly. In 28 Si, ground-state correlations influence largely the detected M1 strength and such ground-state correlations are also responsible for the occurence of a strong M1 transition to a state at Ex = 10.319 MeV in 40 Ca. In 90 Zr only about 10% of the theoretically expected M1 strength is seen in (e,e) and in 140 Ce and 208 Pb none (detection limit 1-2 μ 2 K). In the case of 208 Pb high resolution spectra exist now up to an excitation energy of Ex = approx. 12MeV. The continuous decrease of the M1 strength with mass number is corroborated by the behaviour of strong but very fragmented M2 transitions which are detected in 28 Si, 90 Zr, 140 Ce and 208 Pb concentrated at an excitation energy E x approx. 44A -1 / 3 MeV. In 90 Zr, the distribution of spacings and widths of the many Jπ = 2 states are consistent with a Wigner and Porter-Thomas distribution, respectively. (orig.) 891 KBE/orig. 892 ARA
Directory of Open Access Journals (Sweden)
Alex Petrovici
2014-09-01
Full Text Available Radiation-produced electrons initiate various reaction processes that are important to radiation damage to biomolecules. In this work, the site of attachment of the prehydrated electrons with methyl acetoacetate (MAA, CH3-CO-CH2-COOCH3 at 77 K and subsequent reactions of the anion radical (CH3-CO•−-CH2-COOCH3 in the 77 to ca. 170 K temperature range have been investigated in homogeneous H2O and D2O aqueous glasses by electron spin resonance (ESR spectroscopy. At 77 K, the prehydrated electron attaches to MAA forming the anion radical in which the electron is delocalized over the two carbonyl groups. This species readily protonates to produce the protonated electron adduct radical CH3-C(•OH-CH2-COOCH3. The ESR spectrum of CH3-C(•OH-CH2-COOCH3 in H2O shows line components due to proton hyperfine couplings of the methyl and methylene groups. Whereas, the ESR spectrum of CH3-C(•OH-CH2-COOCH3 in D2O glass shows only the line components due to proton hyperfine couplings of CH3 group. This is expected since the methylene protons in MAA are readily exchangeable in D2O. On stepwise annealing to higher temperatures (ca. 150 to 170 K, CH3-C(•OH-CH2-COOCH3 undergoes bimolecular H-atom abstraction from MAA to form the more stable radical, CH3-CO-CH•-COOCH3. Theoretical calculations using density functional theory (DFT support the radical assignments.
Petrovici, Alex; Adhikary, Amitava; Kumar, Anil; Sevilla, Michael D
2014-09-01
Radiation-produced electrons initiate various reaction processes that are important to radiation damage to biomolecules. In this work, the site of attachment of the prehydrated electrons with methyl acetoacetate (MAA, CH3-CO-CH2-COOCH3) at 77 K and subsequent reactions of the anion radical (CH3-CO•--CH2-COOCH3) in the 77 to ca. 170 K temperature range have been investigated in homogeneous H2O and D2O aqueous glasses by electron spin resonance (ESR) spectroscopy. At 77 K, the prehydrated electron attaches to MAA forming the anion radical in which the electron is delocalized over the two carbonyl groups. This species readily protonates to produce the protonated electron adduct radical CH3-C(•)OH-CH2-COOCH3. The ESR spectrum of CH3-C(•)OH-CH2-COOCH3 in H2O shows line components due to proton hyperfine couplings of the methyl and methylene groups. Whereas, the ESR spectrum of CH3-C(•)OH-CH2-COOCH3 in D2O glass shows only the line components due to proton hyperfine couplings of CH3 group. This is expected since the methylene protons in MAA are readily exchangeable in D2O. On stepwise annealing to higher temperatures (ca. 150 to 170 K), CH3-C(•)OH-CH2-COOCH3 undergoes bimolecular H-atom abstraction from MAA to form the more stable radical, CH3-CO-CH•-COOCH3. Theoretical calculations using density functional theory (DFT) support the radical assignments.
Electron Scattering by biomass molecular fragments
Lima, Marco
2015-09-01
The replacement of fossil fuels by biofuels from renewable sources may not be a definite answer for greenhouse gas emissions problems, but it is a good step towards a sustainable energy strategy. Few per cent of ethanol is being mixed to gasoline in many countries and in some of them, like Brazil, a very aggressive program has been developed, using, in large scale, flex fuel engines that can run with any mixture of gasoline and ethanol, including 100% ethanol. Important points are how to produce ethanol in a sustainable way and with which technology? Biomass is a good candidate to enhance the first generation (produced from Corn in USA and from sugarcane in Brazil) production towards the so-called second-generation ethanol, since it has cellulose and hemicellulose as source of sugars. In order to liberate these sugars for fermentation, it is important to learn how to separate the main components. Chemical routes (acid treatment) and biological routes (enzymatic hydrolysis) are combined and used for these purposes. Atmospheric plasmas can be useful for attacking the biomass in a controlled manner and low energy electrons may have an important role in the process. Recently, we have been studying the interaction of electrons with lignin subunits (phenol, guaiacol, p-coumaryl alcohol), cellulose components, β-D-glucose and cellobiose (β(1-4) linked glucose dimer) and hemicellulose components [2] (β-D-xylose). We also obtained results for the amylose subunits α-D-glucose and maltose (α(1-4) linked glucose dimer). Altogether, the resonance spectra of lignin, cellulose and hemicellulose components establish a physical-chemical basis for electron-induced biomass pretreatment that could be applied to biofuel production. In order to describe a more realistic system (where molecules are ``wet''), we have obtained the shape resonance spectra of phenol-water clusters, as obtained previously from elastic electron scattering calculations. Our results, obtained in a simple
Scattering of electrons from argon atoms
International Nuclear Information System (INIS)
Dasgupta, A.; Bhatia, A.K.
1985-01-01
The scattering of electrons from argon atoms is studied by the method of polarized orbitals. The 3p→d perturbed orbital calculated using the Sternheimer approximation gives the polarizability 14.29a 0 3 . The perturbation of the orbitals 1s, 2s, 2p, and 3s is taken into account by renormalizing the 3p→d orbitals to give the experimental value 11.06a 0 3 . Using only the modified orbital in the total wave function, phase shifts for various partial waves have been calculated in the exchange, exchange-adiabatic, and polarized-orbital approximations. They are compared with the results of the previous calculations. The calculated total elastic, differential, and momentum-transfer cross sections are compared with the experimental results. The elastic total cross sections obtained in the polarized-orbital approximation agree very closely with the recently measured cross sections by Jost et al. and Nickel et al. The critical point (the value of k 2 and theta at which the differential cross section is minimum) is at 0.306 eV and 80 0 , in good agreement with the measurements of Weyhreter et al
Electron-electron scattering and mobilities in semiconductors and quantum wells
International Nuclear Information System (INIS)
Lyo, S.K.
1986-01-01
The effect of electron-electron scattering on the mobility in semiconductors and semiconductor quantum wells is examined. A general exact formula is derived for the mobility, when the electron-electron collision rate is much faster than other scattering rates such as those by ionized impurities and phonons. In this limit, the transport relaxation rate is independent of the carrier's energy and contributions to the inverse mobility from individual scattering mechanism add up. The mobility becomes significantly reduced from its value in the absence of electron-electron scattering. When the collision rates are not necessarily dominated by electron-electron scattering, the mobility is calculated by the Kohler-Sondheimer variational method in the presence of ionized-impurity scattering and acoustic-phonon scattering in a nondegenerate two-dimensional quantum well
The 270 MeV deuteron beam polarimeter at the Nuclotron Internal Target Station
Energy Technology Data Exchange (ETDEWEB)
Kurilkin, P.K. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Moscow State Institute of Radio-engineering Electronics and Automation (Technical University), Moscow (Russian Federation); Ladygin, V.P., E-mail: vladygin@jinr.ru [Joint Institute for Nuclear Research, Dubna (Russian Federation); Moscow State Institute of Radio-engineering Electronics and Automation (Technical University), Moscow (Russian Federation); Uesaka, T. [Center for Nuclear Study, University of Tokyo, Tokyo 113-0033 (Japan); Suda, K. [RIKEN Nishina Center, Saitama (Japan); Gurchin, Yu.V.; Isupov, A.Yu. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Itoh, K. [Department of Physics, Saitama University, Saitama (Japan); Janek, M. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Physics Department, University of Zilina, 010 26 Zilina (Slovakia); Karachuk, J.-T. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Advanced Research Institute for Electrical Engineering, Bucharest (Romania); Kawabata, T. [Center for Nuclear Study, University of Tokyo, Tokyo 113-0033 (Japan); Khrenov, A.N.; Kiselev, A.S.; Kizka, V.A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Kliman, J. [Institute of Physics of Slovak Academy of Sciences, Bratislava (Slovakia); Krasnov, V.A.; Livanov, A.N. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Institute for Nuclear Research, Moscow (Russian Federation); Maeda, Y. [Kyushi University, Hakozaki (Japan); Malakhov, A.I. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Matousek, V.; Morhach, M. [Institute of Physics of Slovak Academy of Sciences, Bratislava (Slovakia)
2011-06-21
A deuteron beam polarimeter has been constructed at the Internal Target Station at the Nuclotron of JINR. The polarimeter is based on spin-asymmetry measurements in the d-p elastic scattering at large angles and the deuteron kinetic energy of 270 MeV. It allows to measure vector and tensor components of the deuteron beam polarization simultaneously.
Scattering of photons from atomic electrons
International Nuclear Information System (INIS)
Pratt, R.H.; Zhou, B.; Bergstrom, P.M. Jr.; Pisk, K.; Suric, T.
1990-01-01
Validity of simpler approaches for elastic and inelastic photon scattering by atoms and ions is assessed by comparison with second-order S-matrix predictions. A simple scheme for elastic scattering based on angle-independent anomalous scattering factors has been found to give useful predictions near and below photoeffect thresholds. In inelastic scattering, major deviations are found from A 2 -based calculations. Extension of free-atom and free-ion cross sections to the dense plasma regime is discussed. 20 refs., 6 figs
International Nuclear Information System (INIS)
Rupnik, K.; Asaf, U.; McGlynn, S.P.
1990-01-01
A linear correlation exists between the electron scattering length, as measured by a pressure shift method, and the polarizabilities for He, Ne, Ar, Kr, and Xe gases. The correlative algorithm has excellent predictive capability for the electron scattering lengths of mixtures of rare gases, simple molecular gases such as H 2 and N 2 and even complex molecular entities such as methane, CH 4
Theory of Raman scattering in coupled electron-phonon systems
Itai, K.
1992-01-01
The Raman spectrum is calculated for a coupled conduction-electron-phonon system in the zero-momentum-transfer limit. The Raman scattering is due to electron-hole excitations and phonons as well. The phonons of those branches that contribute to the electron self-energy and the correction of the electron-phonon vertex are assumed to have flat energy dispersion (the Einstein phonons). The effect of electron-impurity scattering is also incorporated. Both the electron-phonon interaction and the electron-impurity interaction cause the fluctuation of the electron distribution between different parts of the Fermi surface, which results in overdamped zero-sound modes of various symmetries. The scattering cross section is obtained by solving the Bethe-Salpeter equation. The spectrum shows a lower threshold at the smallest Einstein phonon energy when only the electron-phonon interaction is taken into consideration. When impurities are also taken into consideration, the threshold disappears.
RAMAN LIGHT SCATTERING IN PSEUDOSPIN-ELECTRON MODEL AT STRONG PSEUDOSPIN-ELECTRON INTERACTION
Directory of Open Access Journals (Sweden)
T.S.Mysakovych
2004-01-01
Full Text Available Anharmonic phonon contributions to Raman scattering in locally anharmonic crystal systems in the framework of the pseudospin-electron model with tunneling splitting of levels are investigated. The case of strong pseudospin-electron coupling is considered. Pseudospin and electron contributions to scattering are taken into account. Frequency dependences of Raman scattering intensity for different values of model parameters and for different polarization of scattering and incident light are investigated.
Schwinger–Keldysh canonical formalism for electronic Raman scattering
Energy Technology Data Exchange (ETDEWEB)
Su, Yuehua, E-mail: suyh@ytu.edu.cn
2016-03-01
Inelastic low-energy Raman and high-energy X-ray scatterings have made great progress in instrumentation to investigate the strong electronic correlations in matter. However, theoretical study of the relevant scattering spectrum is still a challenge. In this paper, we present a Schwinger–Keldysh canonical perturbation formalism for the electronic Raman scattering, where all the resonant, non-resonant and mixed responses are considered uniformly. We show how to use this formalism to evaluate the cross section of the electronic Raman scattering off an one-band superconductor. All the two-photon scattering processes from electrons, the non-resonant charge density response, the elastic Rayleigh scattering, the fluorescence, the intrinsic energy-shift Raman scattering and the mixed response, are included. In the mean-field superconducting state, Cooper pairs contribute only to the non-resonant response. All the other responses are dominated by the single-particle excitations and are strongly suppressed due to the opening of the superconducting gap. Our formalism for the electronic Raman scattering can be easily extended to study the high-energy resonant inelastic X-ray scattering.
A surprise in the first Born approximation for electron scattering
International Nuclear Information System (INIS)
Treacy, M.M.J.; Van Dyck, D.
2012-01-01
A standard textbook derivation for the scattering of electrons by a weak potential under the first Born approximation suggests that the far-field scattered wave should be in phase with the incident wave. However, it is well known that waves scattered from a weak phase object should be phase-shifted by π/2 relative to the incident wave. A disturbing consequence of this missing phase is that, according to the Optical Theorem, the total scattering cross section would be zero in the first Born approximation. We resolve this mystery pedagogically by showing that the first Born approximation fails to conserve electrons even to first order. Modifying the derivation to conserve electrons introduces the correct phase without changing the scattering amplitude. We also show that the far-field expansion for the scattered waves used in many texts is inappropriate for computing an exit wave from a sample, and that the near-field expansion also give the appropriately phase-shifted result. -- Highlights: ► The first Born approximation is usually invoked as the theoretical physical basis for kinematical electron scattering theory. ► Although it predicts the correct scattering amplitude, it predicts the wrong phase; the scattered wave is missing a prefactor of i. ► We show that this arises because the standard textbook version of the first Born approximation does not conserve electrons. ► We show how this can be fixed.
Recent progress in electron scattering from atoms and molecules
Energy Technology Data Exchange (ETDEWEB)
Brunger, M. J. [Centre for Antimatter-Matter Studies, CAPS, Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia and Institute of Mathematical Sciences, University of Malaya, Kuala Lumpur (Malaysia); Buckman, S. J. [Institute of Mathematical Sciences, University of Malaya, Kuala Lumpur, Malaysia and Centre for Antimatter-Matter Studies, AMPL, Australian National University, Canberra, ACT 0200 (Australia); Sullivan, J. P.; Palihawadana, P. [Centre for Antimatter-Matter Studies, AMPL, Australian National University, Canberra, ACT 0200 (Australia); Jones, D. B. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, SA 5001 (Australia); Chiari, L.; Pettifer, Z. [Centre for Antimatter-Matter Studies, CAPS, Flinders University, GPO Box 2100, Adelaide, SA 5001 (Australia); Silva, G. B. da [Centre for Antimatter-Matter Studies, CAPS, Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia and Universidade Federal de Mato Grosso, Barra do Garças, Mato Grosso (Brazil); Lopes, M. C. A. [Centre for Antimatter-Matter Studies, CAPS, Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia and Departamento de Fisica, Universidade Federal de Juiz de Fora, Juiz de Fora, MG (Brazil); Duque, H. V. [Departamento de Fisica, Universidade Federal de Juiz de Fora, Juiz de Fora, MG (Brazil); Masin, Z.; Gorfinkiel, J. D. [Department of Physical Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA (United Kingdom); Garcia, G. [Instituto de Fisica Fundamental, CSIC, Madrid E-28006 (Spain); Hoshino, M.; Tanaka, H. [Department of Physics, Sophia University, Tokyo, 102-8554 (Japan); Limão-Vieira, P. [Laboratório de Colisões Atómicas e Moleculares, CEFITEC, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)
2014-03-05
We present and discuss recent results, both experimental and theoretical (where possible), for electron impact excitation of the 3s[3/2 ]{sub 1} and 3s′[1/2 ]{sub 1} electronic states in neon, elastic electron scattering from the structurally similar molecules benzene, pyrazine, and 1,4-dioxane and excitation of the electronic states of the important bio-molecule analogue α-tetrahydrofurfuryl alcohol. While comparison between theoretical and experimental results suggests that benchmarked cross sections for electron scattering from atoms is feasible in the near-term, significant further theoretical development for electron-molecule collisions, particularly in respect to discrete excitation processes, is still required.
International Nuclear Information System (INIS)
Burtin, Etienne
1996-01-01
This research thesis reports the development of a muon-based polarimeter which implements elastic scattering of muons on a target of polarised electrons. In its first part, it describes the deeply inelastic scattering process, and presents the theoretical framework for the interpretation of experimental results. The author describes the experimental installation, and the measurement of the beam polarisation by elastic scattering on a target of polarised electrons. He reports the analysis of data obtained with a 190 GeV beam, the discussion and assessment of error sources, the comparison of these results with other measurements using the muon in-flight disintegration, and with the prediction obtained by the beam line simulation. He finally reports the results of the SMC experiment obtained for the proton and the deuteron, and demonstrates the verification of the Bjorken sum rule
Determination of deuteron beam polarizations at COSY
Directory of Open Access Journals (Sweden)
D. Chiladze
2006-05-01
Full Text Available The vector (P_{z} and tensor (P_{zz} polarizations of a deuteron beam have been measured using elastic deuteron–carbon scattering at 75.6 MeV and deuteron-proton scattering at 270 MeV. After acceleration to 1170 MeV inside the COSY storage ring, the polarizations of the deuterons were remeasured by studying the analyzing powers of a variety of nuclear reactions. For this purpose a hydrogen cluster target was employed at the ANKE magnetic spectrometer, which is situated at an internal target position in the ring. The overall precisions obtained were about 4% for both P_{z} and P_{zz}. Though all the measurements were consistent with the absence of depolarization during acceleration, only an upper limit of about 6% could be placed on such an effect.
Electron Raman scattering in asymmetrical multiple quantum wells
International Nuclear Information System (INIS)
Betancourt-Riera, R; Rosas, R; Marin-Enriquez, I; Riera, R; Marin, J L
2005-01-01
Optical properties of asymmetrical multiple quantum wells for the construction of quantum cascade lasers are calculated, and expressions for the electronic states of asymmetrical multiple quantum wells are presented. The gain and differential cross-section for an electron Raman scattering process are obtained. Also, the emission spectra for several scattering configurations are discussed, and the corresponding selection rules for the processes involved are studied; an interpretation of the singularities found in the spectra is given. The electron Raman scattering studied here can be used to provide direct information about the efficiency of the lasers
Stimulated Raman scattering and hot-electron production
International Nuclear Information System (INIS)
Drake, R.P.; Turner, R.E.; Lasinski, B.F.; Estabrook, K.G.; Campbell, E.M.; Wang, C.L.; Phillion, D.W.; Williams, E.A.; Kruer, W.L.
1985-01-01
High-intensity laser light can excite parametric instabilities that scatter or absorb it. One instability that can arise when laser light penetrates a plasma is sub-quarter-critical stimulated Raman (SQSR) scattering. It occurs below the quarter-critical density of the incident light and involves the decay of the incident light wave into a scattered light wave and electron plasma wave. The scattered-light wavelength ranges from 1 to 2 times that of the incident light, depending on the plasma density and temperature. This article reports studies of SQSR scattering and hot-electron production in plasmas produced by irradiating thick gold targets with up to 4 kJ of 0.53-μm light in 1-ns (FWHM) pulses. These studies have important implications for laser fusion. Hot electrons attributed to the SQSR instability can increase the difficulty of achieving high-gain implosions by penetrating and preheating the fusion fuel
Scattering of polarized low-energy electrons by ferromagnetic metals
International Nuclear Information System (INIS)
Helman, J.S.
1981-01-01
A source of spin polarized electrons with remarkable characteristics based on negative electron affinity (NEA) GaAs has recently been developed. It constitutes a unique tool to investigate spin dependent interactions in electron scattering processes. The characteristics and working principles of the source are briefly described. Some theoretical aspects of the scattering of polarized low-energy electrons by ferromagnetic metals are discussed. Finally, the results of the first polarized low-energy electron diffraction experiment using the NEA GaAs source are reviewed; they give information about the surface magnetization of ferromagnetic Ni (110). (Author) [pt
Electron Dynamics by Inelastic X-Ray Scattering
Schülke, Winfried
2007-01-01
The book offers the first comprehensive review of experimental methods, theory, and successful applications of synchrotron radiation based inelastic X-ray scattering (IXS) spectroscopy, which enables the investigation of electron dynamics in condensed matter (correlated motion and excitation).
Electron scattering from the octupole band in 238U
International Nuclear Information System (INIS)
Hirsch, A.; Creswell, C.; Bertozzi, W.; Heisenberg, J.; Hynes, M.V.; Kowalski, S.; Miska, H.; Norum, B.; Rad, F.N.; Sargent, C.P.; Sasanuma, T.; Turchinetz, W.
1978-01-01
A simple model for nuclear surface vibrations in permanently deformed nuclei does well in reproducing electron scattering cross sections of rotational levels built on a K/sup π/= 0 - intrinsic octupole vibration in 238 U
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.
Expansions for model-independent analyses of inelastic electron scattering
International Nuclear Information System (INIS)
Jackson, D.F.; Hilton, J.M.; Roberts, A.C.M.
1977-01-01
It is noted that the commonly-used Fourier-Bessel expansion for the transition density for inelastic electron scattering depends sensitively on an arbitrary parameter and is not realistic at large distances. Alternative expansions are suggested. (author)
Structure functions in electron-nucleon deep inelastic scattering
Energy Technology Data Exchange (ETDEWEB)
Saleem, M.; Fazal-E-Aleem (University of the Punjab, Lahore (Pakistan). Dept. of Physics)
1982-06-26
The phenomenological expressions for the structure functions in electron-nucleon deep inelastic scattering are proposed and are shown to satisfy the experimental data as well as a number of sum rules.
Significance of matrix diagonalization in modelling inelastic electron scattering
Energy Technology Data Exchange (ETDEWEB)
Lee, Z. [University of Ulm, Ulm 89081 (Germany); Hambach, R. [University of Ulm, Ulm 89081 (Germany); University of Jena, Jena 07743 (Germany); Kaiser, U.; Rose, H. [University of Ulm, Ulm 89081 (Germany)
2017-04-15
Electron scattering is always applied as one of the routines to investigate nanostructures. Nowadays the development of hardware offers more and more prospect for this technique. For example imaging nanostructures with inelastic scattered electrons may allow to produce component-sensitive images with atomic resolution. Modelling inelastic electron scattering is therefore essential for interpreting these images. The main obstacle to study inelastic scattering problem is its complexity. During inelastic scattering, incident electrons entangle with objects, and the description of this process involves a multidimensional array. Since the simulation usually involves fourdimensional Fourier transforms, the computation is highly inefficient. In this work we have offered one solution to handle the multidimensional problem. By transforming a high dimensional array into twodimensional array, we are able to perform matrix diagonalization and approximate the original multidimensional array with its twodimensional eigenvectors. Our procedure reduces the complicated multidimensional problem to a twodimensional problem. In addition, it minimizes the number of twodimensional problems. This method is very useful for studying multiple inelastic scattering. - Highlights: • 4D problems are involved in modelling inelastic electron scattering. • By means of matrix diagonalization, the 4D problems can be simplified as 2D problems. • The number of 2D problems is minimized by using this approach.
Runaway relativistic electron scattering on the plazma oscillations in tokamak
International Nuclear Information System (INIS)
Krasovitskij, V.B.; Razdorski, V.G.
1980-01-01
The dynamics of fast electrons in a tolamak plasma with the presence of the constant external electric field have been inveatigated. It is shown that the occurrence of the relativistic electrons ''tail'' of the distribution function is followed by an intensive plasma oscillation swinging under conditions of the anomalous Doppler effect and their large angle scattering in the momentum space. A part of scattered electrons is captured by tokamak inhomogeneous magnetic field and causes the occurrence of a new low frequency alfven instability under conditions of magnetic drift resonance followed by quasilinear diffusion of relativistic electrons along the small radius of the torus. The flux of runaway electrons scattered on plasma oscillations has been found. A nonlinear diffusion equation has been derived for the flux of captured electrons. The equation defines the carrying out of fast particles from the plasma filament center to its periphery depending on the external magnetic field and plasma parameters
Inelastic electron photon scattering at moderate four momentum transfers
International Nuclear Information System (INIS)
Berger, C.; Genzel, H.; Grigull, R.; Lackas, W.; Raupach, F.; Klovning, A.; Lillestoel, E.; Skard, J.A.; Ackermann, H.; Buerger, J.
1980-10-01
We present new high statistics data on hadron production in photon photon reactions. The data are analyzed in terms of an electron photon scattering formalism. The dependence of the total cross section on Q 2 , the four momentum transfer squared of the scattered electron, and on the mass W of the hadronic system is investigated. The data are compared to predictions from Vector Dominance and the quark model. (orig.)
Analytical fits to Fink's electron scattering amplitudes, 1
International Nuclear Information System (INIS)
Hayashi, Shigeo
1984-01-01
Numerical data of the direct and spin-flip amplitudes for elastic electron scattering, calculated previously by Fink and co-workers, were expressed in the form Σc 1 exp(-c 2 x+ic 3 +ic 4 ), where x=1-cos theta,theta being a scattering angle. The adjustable c-parameters were determined by the use of a simplex method. Results are reported for carbon at incident electron energies of 25-1000eV. (author)
Electron Raman scattering in a cylindrical quantum dot
International Nuclear Information System (INIS)
Zhong Qinghu; Yi Xuehua
2012-01-01
Electron Raman scattering (ERS) is investigated in a CdS cylindrical quantum dot (QD). The differential cross section is calculated as a function of the scattering frequency and the size of the QD. Single parabolic conduction and valence bands are assumed, and singularities in the spectrum are found and interpreted. The selection rules for the processes are also studied. The ERS studied here can be used to provide direct information about the electron band structure of these systems. (semiconductor physics)
Multiple pole in the electron--hydrogen-atom scattering amplitude
International Nuclear Information System (INIS)
Amusia, M.Y.; Kuchiev, M.Y.
1982-01-01
It is demonstrated that the amplitude for electron--hydrogen-atom forward scattering has the third-order pole at the point E = -13.6 eV, E being the energy of the incident electron. The coefficients which characterize the pole are calculated exactly. The invalidity of the Born approximation is proved. The contribution of the pole singularity to the dispersion relation for the scattering amplitude is discussed
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
Jacob's ladder of approximations to paraxial dynamic electron scattering
Lubk, A.; Rusz, Jan
2015-01-01
Dynamical scattering theory describes the dominant scattering process of beam electrons at targets in the transmission electron microscope (TEM). Hence, practically every quantitative TEM study has to consider its ramifications, typically by some approximate modeling. Here, we elaborate on a hierarchy within the various approximations focusing on the two principal approaches used in practice, Bloch wave and multislice. We reveal characteristic differences in the capability of these methods to...
Scattered radiation from applicators in clinical electron beams
International Nuclear Information System (INIS)
Battum, L J van; Zee, W van der; Huizenga, H
2003-01-01
In radiotherapy with high-energy (4-25 MeV) electron beams, scattered radiation from the electron applicator influences the dose distribution in the patient. In most currently available treatment planning systems for radiotherapy this component is not explicitly included and handled only by a slight change of the intensity of the primary beam. The scattered radiation from an applicator changes with the field size and distance from the applicator. The amount of scattered radiation is dependent on the applicator design and on the formation of the electron beam in the treatment head. Electron applicators currently applied in most treatment machines are essentially a set of diaphragms, but still do produce scattered radiation. This paper investigates the present level of scattered dose from electron applicators, and as such provides an extensive set of measured data. The data provided could for instance serve as example input data or benchmark data for advanced treatment planning algorithms which employ a parametrized initial phase space to characterize the clinical electron beam. Central axis depth dose curves of the electron beams have been measured with and without applicators in place, for various applicator sizes and energies, for a Siemens Primus, a Varian 2300 C/D and an Elekta SLi accelerator. Scattered radiation generated by the applicator has been found by subtraction of the central axis depth dose curves, obtained with and without applicator. Scattered radiation from Siemens, Varian and Elekta electron applicators is still significant and cannot be neglected in advanced treatment planning. Scattered radiation at the surface of a water phantom can be as high as 12%. Scattered radiation decreases almost linearly with depth. Scattered radiation from Varian applicators shows clear dependence on beam energy. The Elekta applicators produce less scattered radiation than those of Varian and Siemens, but feature a higher effective angular variance. The scattered
Total cross sections for electron scattering by He
International Nuclear Information System (INIS)
De Heer, F.J.; Jansen, R.H.J.
1977-01-01
A set of total cross sections for scattering of electrons by He has been evaluated over the energy range of zero to 3000 eV by means of the analysis of experiments and theories on total cross sections for elastic scattering, ionisation and excitation, and on differential cross sections for elastic and inelastic scattering. Between 0 and 19.8 eV, where no inelastic processes occur, the total cross sections for scattering are equal to those for elastic scattering. Above 19.8 eV total cross sections for scattering of electrons have been evaluated by adding those for ionisation, excitation and elastic scattering. The total cross sections thus obtained are probably accurate to about 5% over a large part of the energy range. They appear to be in very good agreement with the recent experimental results of Blaauw et al. (J. Phys. B.; 10:L299 (1977)). The present results have already proved useful for application in the dispersion relation for forward scattering in electron-helium collisions. (author)
A multislice theory of electron inelastic scattering in a solid
International Nuclear Information System (INIS)
Wang, Z.L.
1989-01-01
A multislice theory is proposed to solve Yoshioka's coupling equations for elastic and inelastic scattered high-energy electrons in a solid. This method is capable, in principle, of including the non-periodic crystal structures and the electron multiple scattering among all the excited states in the calculations. It is proved that the proposed theory for calculating the energy-filtered inelastic images, based on the physical optics approach, is equivalent to the quantum-mechanical theory under some approximations. The basic theory of simulating the energy-filtered inelastic image of core-shell losses and thermal diffuse scattering is outlined. (orig.)
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)
Energy Technology Data Exchange (ETDEWEB)
Raynal, J. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1963-07-01
The optical model has been applied with success to the elastic scattering of particles of spin 0 and 1/2 and to a lesser degree to that of deuterons. For particles of spin l/2, an LS coupling term is ordinarily used; this term is necessary to obtain a polarization; for deuterons, this coupling has been already introduced, but the possible forms of potentials are more numerous (in this case, scalar products of a second rank spin tensor with a tensor of the same rank in space or momentum can occur). These terms which may be necessary are primarily important for the tensor polarization. This problem is of particular interest at Saclay since a beam of polarized deuterons has become available. The FORTRAN program SPM 037 permits the study of the effect of tensorial potentials constructed from the distance of the deuteron from the target and its angular momentum with respect to it. This report should make possible the use and even the modification of the program. It consists of: a description of the problem and of the notation employed, a presentation of the methods adopted, an indication of the necessary data and how they should be introduced, and finally tables of symbols which are in equivalence or common statements: these tables must be considered when making any modification. (author) [French] Le modele optique a ete applique avec succes a la diffusion elastique des particules de spin nul et 1/2 et dans une moindre mesure a celle des deutons. Pour les particules de spin 1/2, on utilise habituellement un couplage LS, necessaire pour calculer la polarisation; pour les deutons, ce couplage a deja ete introduit, mais les formes de potentiel possibles sont plus nombreuses (intervention de produits scalaires d'un tenseur d'ordre 2 de spin avec un tenseur du meme ordre d'espace ou d'impulsion) et celles qui peuvent etre eventuellement necessaires ont une importance capitale pour la polarisation tensorielle. Ce probleme revet a Saclay un interet
Energy Technology Data Exchange (ETDEWEB)
Raynal, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1963-07-01
The optical model has been applied with success to the elastic scattering of particles of spin 0 and 1/2 and to a lesser degree to that of deuterons. For particles of spin l/2, an LS coupling term is ordinarily used; this term is necessary to obtain a polarization; for deuterons, this coupling has been already introduced, but the possible forms of potentials are more numerous (in this case, scalar products of a second rank spin tensor with a tensor of the same rank in space or momentum can occur). These terms which may be necessary are primarily important for the tensor polarization. This problem is of particular interest at Saclay since a beam of polarized deuterons has become available. The FORTRAN program SPM 037 permits the study of the effect of tensorial potentials constructed from the distance of the deuteron from the target and its angular momentum with respect to it. This report should make possible the use and even the modification of the program. It consists of: a description of the problem and of the notation employed, a presentation of the methods adopted, an indication of the necessary data and how they should be introduced, and finally tables of symbols which are in equivalence or common statements: these tables must be considered when making any modification. (author) [French] Le modele optique a ete applique avec succes a la diffusion elastique des particules de spin nul et 1/2 et dans une moindre mesure a celle des deutons. Pour les particules de spin 1/2, on utilise habituellement un couplage LS, necessaire pour calculer la polarisation; pour les deutons, ce couplage a deja ete introduit, mais les formes de potentiel possibles sont plus nombreuses (intervention de produits scalaires d'un tenseur d'ordre 2 de spin avec un tenseur du meme ordre d'espace ou d'impulsion) et celles qui peuvent etre eventuellement necessaires ont une importance capitale pour la polarisation tensorielle. Ce probleme revet a Saclay un interet particulier depuis la mise
Study of the electrons elastic scattering by atoms through pseudopotentials
International Nuclear Information System (INIS)
Bettega, M.H.F.
1990-01-01
Pseudopotentials allow an extraordinary simplification in the calculation of the electronic structure of atoms, molecules and crystals. Though they have been used extensively for electronic structure calculations, little is known of their applicability to scattering. A study of the pseudopotentials of Bachelet, Hamann and Schuter in the electron scattering by atoms was made, calculating phase-shifts and cross sections for angular momenta 1=0,1 and 2 and energy up to 5 R y. The results for the pseudopotential were compared all-electron calculations. The agreement is very good in a broad energy band. A simplification of the calculation of scattering by complex molecules where an all-electron calculation is impossible is aimed. (author)
Inelastic scattering of quasifree electrons on O7+ projectiles
International Nuclear Information System (INIS)
Toth, G.; Grabbe, S.; Richard, P.; Bhalla, C.P.
1996-01-01
Absolute doubly differential cross sections (DDCS close-quote s) for the resonant inelastic scattering of quasifree target electrons on H-like projectiles have been measured. Electron spectra for 20.25-MeV O 7+ projectiles on an H 2 target were measured. The spectra contain a resonant contribution from the 3l3l ' doubly excited states of O 6+ , which decay predominantly to the 2l states of the O 7+ via autoionization, and a nonresonant contribution from the direct excitation of the projectiles to the O 7+ (2l) state by the quasifree target electrons. Close-coupling R-matrix calculations for the inelastic scattering of free electrons on O 7+ ions were performed. The relation between the electron-ion inelastic scattering calculation and the electron DDCS close-quote s for the ion-atom collision was established by using the inelastic scattering model (ISM). We found excellent agreement between the theoretical and measured resonant peak positions and relative peak heights. The calculated absolute double differential cross sections for the resonance processes are also in good agreement with the measured data. The implication is that collisions of highly charged ions on hydrogen can be used to obtain high-resolution, angle- resolved differential inelastic electron-scattering cross section. copyright 1996 The American Physical Society
Path integral approach to electron scattering in classical electromagnetic potential
International Nuclear Information System (INIS)
Xu Chuang; Feng Feng; Li Ying-Jun
2016-01-01
As is known to all, the electron scattering in classical electromagnetic potential is one of the most widespread applications of quantum theory. Nevertheless, many discussions about electron scattering are based upon single-particle Schrodinger equation or Dirac equation in quantum mechanics rather than the method of quantum field theory. In this paper, by using the path integral approach of quantum field theory, we perturbatively evaluate the scattering amplitude up to the second order for the electron scattering by the classical electromagnetic potential. The results we derive are convenient to apply to all sorts of potential forms. Furthermore, by means of the obtained results, we give explicit calculations for the one-dimensional electric potential. (paper)
Scattering of electrons in copper by a Frenkel pair defect
Energy Technology Data Exchange (ETDEWEB)
Lodder, A.; Rijsdijk, G.A.; Bukman, D.J.; Baratta, A.J.; Molenaar, J.
1988-06-01
The Korringa-Kohn-Rostoker (KKR) Green function extended-defect formalism, used to describe the scattering of Bloch electrons in a dilute alloy, is generalised to include an asymmetric defect centred on a lattice site. The revised theory is then used to investigate conduction electron scattering from Frenkel pairs in Cu. Such defects consist of two self-interstitial atoms centred on a vacant lattice site forming a dumb-bell oriented along the <100> axis. The generalised formalism allows one to calculate the cluster t matrix T for the Frenkel pair cluster including the surrounding displaced nearest neighbours. It was found that the interstitials at the vacant lattice site could still be treated within the muffin-tin potential as a central scatterer characterised by a t matrix which is non-diagonal in the angular momentum. Electron scattering rates and Dingle temperatures are calculated and discussed in view of preliminary experimental results.
Scattering of electrons in copper by a Frenkel pair defect
International Nuclear Information System (INIS)
Lodder, A.; Rijsdijk, G.A.; Bukman, D.J.; Baratta, A.J.; Molenaar, J.
1988-01-01
The Korringa-Kohn-Rostoker (KKR) Green function extended-defect formalism, used to describe the scattering of Bloch electrons in a dilute alloy, is generalised to include an asymmetric defect centred on a lattice site. The revised theory is then used to investigate conduction electron scattering from Frenkel pairs in Cu. Such defects consist of two self-interstitial atoms centred on a vacant lattice site forming a dumb-bell oriented along the axis. The generalised formalism allows one to calculate the cluster t matrix T for the Frenkel pair cluster including the surrounding displaced nearest neighbours. It was found that the interstitials at the vacant lattice site could still be treated within the muffin-tin potential as a central scatterer characterised by a t matrix which is non-diagonal in the angular momentum. Electron scattering rates and Dingle temperatures are calculated and discussed in view of preliminary experimental results. (author)
Nucleon-deuteron low energy parameters
International Nuclear Information System (INIS)
Zankel, H.; Mathelitsch, L.
1983-01-01
Momentum space Fadeev equations are solved for nucleon-deuteron scattering and effective range parameters are calculated. A reverse trend is found in the two spin states by 4 asub(nd) 4 asub(pd) and 2 asub(pd) 2 asub(nd) which is in agreement with a configuration space calculation, but in conflict with all existing experiments. The Coulomb contributions to the effective range are small in quartet but sizeable in doublet scattering. (Author)
Angular momentum effects in electron scattering from atoms
International Nuclear Information System (INIS)
Williams, J F; Cvejanovie, D; Samarin, S; Pravica, L; Napier, S; Sergeant, A
2007-01-01
This paper concerns angular momentum-dependent phenomena in excited gas-phase atoms using incident photons or electrons in scattering experiments. A brief overview indicates the main capabilities of experimental techniques and the information which can be deduced about atomic structure and dynamics from conservation of momenta with measurement of polarization and detection of the number of emerging electrons, photons and ions. Maximum information may be obtained when the incident particles and the targets are state-selected both before and after scattering. The fundamental scattering amplitudes and their relative phases, and consequently derived quantities such as the parameters describing the electron charge cloud of the atomic target, have enabled significant advances of understanding of collision mechanisms. The angular momentum-dependent scattering probabilities change when, for example, the spin-orbit interaction for the target electrons becomes large compared with the Coulomb electron-electron interactions and also when electron exchange and the relative orientation of the electron spins change. Several examples are discussed to indicate significant principles and recent advances. Major contributions to this field from the technology associated with electron spin production and detection time, as well as time-coincidence detection, are discussed. New results from the authors' laboratory are presented
Nucleon momentum distribution in deuteron and other nuclei within the light-front dynamics method
International Nuclear Information System (INIS)
Antonov, A.N.; Gaidarov, M.K.; Ivanov, M.V.; Kadrev, D.N.; Krumova, G.Z.; Hodgson, P.E.; Geramb, H.V. von
2002-01-01
The relativistic light-front dynamics (LFD) method has been shown to give a correct description of the most recent data for the deuteron monopole and quadrupole charge form factors obtained at the Jefferson Laboratory for elastic electron-deuteron scattering for six values of the squared momentum transfer between 0.66 and 1.7 (GeV/c) 2 . The good agreement with the data is in contrast with the results of the existing nonrelativistic approaches. In this work we first make a complementary test of the LFD applying it to calculate another important characteristic, the nucleon momentum distribution n(q) of the deuteron, using six invariant functions f i (i=1,...,6) instead of two (S and D waves) in the nonrelativistic case. The comparison with the y-scaling data shows the decisive role of the function f 5 which at q≥500 MeV/c exceeds all other f functions (as well as the S and D waves) for the correct description of n(q) of the deuteron in the high-momentum region. Comparison with other calculations using S and D waves corresponding to various nucleon-nucleon potentials is made. Second, using clear indications that the high-momentum components of n(q) in heavier nuclei are related to those in the deuteron, we develop an approach within the natural orbital representation to calculate n(q) in (A,Z) nuclei on the basis of the deuteron momentum distribution. As examples, n(q) in 4 He, 12 C, and 56 Fe are calculated and good agreement with the y-scaling data is obtained
Scattered radiation from applicators in clinical electron beams.
Battum, L.J. van; Zee, W. van der; Huizenga, H.
2003-01-01
In radiotherapy with high-energy (4-25 MeV) electron beams, scattered radiation from the electron applicator influences the dose distribution in the patient. In most currently available treatment planning systems for radiotherapy this component is not explicitly included and handled only by a slight
Inclusive and exclusive deep-inelastic electron scattering
International Nuclear Information System (INIS)
Morgenstern, J.
1985-11-01
In this talk, I will present some deep inelastic electron scattering experiments done recently at Saclay with the purpose of studying high momentum components in the nucleus, many body effects as correlations, exchange currents, and the electron-nucleon interaction inside the nuclear medium. For that purpose we have performed (e,e') and (ee'p) experiments. When we detect only the scattered electron, we get some average properties less sensitive to final state interaction; in ee'p measurements we are more specific
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.)
Influence of scattering processes on electron quantum states in nanowires
Directory of Open Access Journals (Sweden)
Pozdnyakov Dmitry
2007-01-01
Full Text Available AbstractIn the framework of quantum perturbation theory the self-consistent method of calculation of electron scattering rates in nanowires with the one-dimensional electron gas in the quantum limit is worked out. The developed method allows both the collisional broadening and the quantum correlations between scattering events to be taken into account. It is an alternativeper seto the Fock approximation for the self-energy approach based on Green’s function formalism. However this approach is free of mathematical difficulties typical to the Fock approximation. Moreover, the developed method is simpler than the Fock approximation from the computational point of view. Using the approximation of stable one-particle quantum states it is proved that the electron scattering processes determine the dependence of electron energy versus its wave vector.
Neutrino-electron scattering. Progress report
International Nuclear Information System (INIS)
White, D.H.
1982-01-01
We present here a progress report on an experiment to measure the cross section for nu/sub μ/e scattering at the Brookhaven AGS. A wide band focussing horn is used with a neutrino beam energy centered at 1.5 GeV. We have in hand measurements with nu/sub μ/ and anti nu/sub μ/ beams but we present preliminary data on the nu/sub μ/ beam running only. We also measure the reactions: nu/sub μ/ + n → μ - + p and nu/sub e/ + n → e - + p which will be used in normalization and in background estimation
New approximation for Glauber theory on stripping of relativistic deuterons
International Nuclear Information System (INIS)
Nissen-Meyer, S.A.
1978-03-01
The momentum distribution of forward protons from relativistic collisions of deuterons with nuclei is computed from a Glauber theoretical Ansatz of Bertocchi and Tekou. The outgoing proton-neutron scattering state (disintegrated deuteron) with a plane wave minus the components of this plane wave along the deuteron bound state vector is approximated. With no fitted parameters good agreement is found with data from the reaction d + C 12 → p + X in the region corresponding to nonrelativistic Fermi momenta in the forward direction. At more relativistic Fermi momenta, the model deviates more from the data, which can be due to incorrect choice of the short distance part of the deuteron wave function as well as off-shell effects in the deuteron
Characterization of Deuteron-Deuteron Neutron Generators
Waltz, Cory Scott
A facility based on a next-generation, high-flux D-D neutron generator (HFNG) was commissioned at the University of California Berkeley. The characterization of the HFNG is presented in the following study. The current generator design produces near mono-energetic 2.45 MeV neutrons at outputs of 108 n/s. Calculations provided show that future conditioning at higher currents and voltages will allow for a production rate over 1010 n/s. Characteristics that effect the operational stability include the suppression of the target-emitted back streaming electrons, target sputtering and cooling, and ion beam optics. Suppression of secondary electrons resulting from the deuterium beam striking the target was achieved via the implementation of an electrostatic shroud with a voltage offset of greater than -400 V relative to the target. Ion beam optics analysis resulted in the creation of a defocussing extraction nozzle, allowing for cooler target temperatures and a more compact design. To calculate the target temperatures, a finite difference method (FDM) solver incorporating the additional heat removal effects of subcooled boiling was developed. Validation of the energy balance results from the finite difference method calculations showed the iterative solver converged to heat removal results within about 3% of the expected value. Testing of the extraction nozzle at 1.43 mA and 100 kV determined that overheating of the target did not occur as the measured neutron flux of the generator was near predicted values. Many factors, including the target stopping power, deuterium atomic species, and target loading ratio, affect the flux distribution of the HFNG neutron generator. A detailed analysis to understand these factors effects is presented. Comparison of the calculated flux of the neutron generator using deuteron depth implantation data, neutron flux distribution data, and deuterium atomic species data matched the experimentally calculated flux determined from indium foil
Variational methods in electron-atom scattering theory
Nesbet, Robert K
1980-01-01
The investigation of scattering phenomena is a major theme of modern physics. A scattered particle provides a dynamical probe of the target system. The practical problem of interest here is the scattering of a low energy electron by an N-electron atom. It has been difficult in this area of study to achieve theoretical results that are even qualitatively correct, yet quantitative accuracy is often needed as an adjunct to experiment. The present book describes a quantitative theoretical method, or class of methods, that has been applied effectively to this problem. Quantum mechanical theory relevant to the scattering of an electron by an N-electron atom, which may gain or lose energy in the process, is summarized in Chapter 1. The variational theory itself is presented in Chapter 2, both as currently used and in forms that may facilitate future applications. The theory of multichannel resonance and threshold effects, which provide a rich structure to observed electron-atom scattering data, is presented in Cha...
Continuum multiple-scattering approach to electron-molecule scattering and molecular photoionization
International Nuclear Information System (INIS)
Dehmer, J.L.; Dill, D.
1979-01-01
The multiple-scattering approach to the electronic continuum of molecules is described. The continuum multiple-scattering model (CMSM) was developed as a survey tool and, as such was required to satisfy two requirements. First, it had to have a very broad scope, which means (i) molecules of arbitrary geometry and complexity containing any atom in the periodic system, (ii) continuum electron energies from 0-1000 eV, and (iii) capability to treat a large range of processes involving both photoionization and electron scattering. Second, the structure of the theory was required to lend itself to transparent, physical interpretation of major spectral features such as shape resonances. A comprehensive theoretical framework for the continuum multiple scattering method is presented, as well as its applications to electron-molecule scattering and molecular photoionization. Highlights of recent applications in these two areas are reviewed. The major impact of the resulting studies over the last few years has been to establish the importance of shape resonances in electron collisions and photoionization of practically all (non-hydride) molecules
Parity nonconservation in polarized electron scattering at high energies
International Nuclear Information System (INIS)
Prescott, C.Y.
1979-10-01
Recent observations of parity violation in inelastic scattering of electrons at high energy is discussed with reference to the process e(polarized) + D(unpolarized) → e + X. The kinetics of this process, the idealized case of scattering from free quark targets, experimental techniques and results, and relations to atomic physics of parity violation in bismuth and thallium atoms with a model independent analysis. 17 references
Resonance electronic Raman scattering in rare earth crystals
International Nuclear Information System (INIS)
Williams, G.M.
1988-01-01
The intensities of Raman scattering transitions between electronic energy levels of trivalent rare earth ions doped into transparent crystals were measured and compared to theory. A particle emphasis was placed on the examination of the effect of intermediate state resonances on the Raman scattering intensities. Two specific systems were studied: Ce 3+ (4f 1 ) in single crystals of LuPO 4 and Er 3+ (4f 11 ) in single crystals of ErPO 4 . 134 refs., 92 figs., 33 tabs
Inclusive quasielastic and deep inelastic electron scattering at high energies
International Nuclear Information System (INIS)
Day, D.B.
1990-01-01
With high electron energies a kinematic regime can be reached where it will be possible to separate quasielastic and deep inelastic scattering. We present a short description of these processes which dominate the inclusive spectrum. Using the highest momentum transfer data available to guide our estimates, we give the kinematic requirements and the cross sections expected. These results indicate that inclusive scattering at high q has a yet unfilled potential. 18 refs., 13 figs
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.)
Nucleons, mesons and quarks: the electron scattering approach
International Nuclear Information System (INIS)
Frois, B.
1985-05-01
A few examples of the research carried out by electron scattering in order to elucidate the relevant degrees of freedom for nuclear physics. Is considered first quasielastic scattering from 3 He which gives some insight into the properties of the nucleon in the nuclear medium. Then examples of meson exchange currents are presented. Finally, the present status of our understanding of shorter range effects is discussed
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.
Terahertz Plasma Waves in Two Dimensional Quantum Electron Gas with Electron Scattering
International Nuclear Information System (INIS)
Zhang Liping
2015-01-01
We investigate the Terahertz (THz) plasma waves in a two-dimensional (2D) electron gas in a nanometer field effect transistor (FET) with quantum effects, the electron scattering, the thermal motion of electrons and electron exchange-correlation. We find that, while the electron scattering, the wave number along y direction and the electron exchange-correlation suppress the radiation power, but the thermal motion of electrons and the quantum effects can amplify the radiation power. The radiation frequency decreases with electron exchange-correlation contributions, but increases with quantum effects, the wave number along y direction and thermal motion of electrons. It is worth mentioning that the electron scattering has scarce influence on the radiation frequency. These properties could be of great help to the realization of practical THz plasma oscillations in nanometer FET. (paper)
Electromagnetic structure of the deuteron
International Nuclear Information System (INIS)
Gilman, R.; Gross, Franz
2001-01-01
Recent measurements of the deuteron electromagnetic structure functions A, B, and T 20 extracted from high energy elastic ed scattering, and the cross sections and asymmetries extracted from high energy photodisintegration gamma + d to n + p, are reviewed and compared to theory. The theoretical calculations range from nonrelativistic and relativistic models using the traditional meson and baryon degrees of freedom, to effective field theories, to models based on the underlying quark and gluon degrees of freedom of QCD, including nonperturbative quark cluster models and perturbative QCD. We review what has been learned from these experiments, and discuss why elastic ed scattering and photodisintegration seem to require very different theoretical approaches, even though they are closely related experimentally
P-odd effects in the e-d scattering in the vector-like theories
International Nuclear Information System (INIS)
Gakh, G.I.
1979-01-01
P-odd effects in elastic electron-deuteron scattering, due to the weak neutral currents, are analyzed in the framework of the vector-like theories. Considered is the case of the most general form of the P-invariance breaking in the elastic e - d scattering amplitude in both the leptonic and hadronic vertices. It is found that in the vector-like theories the parity violation in the electro-deuteron elastic scattering is confined in the hadronic vertex, while in the Weinberg-Salam model it is confined in the leptonic vertex. In the vector-like theories the asymmetry in the scattering of longitudinally polarized electrons by nonpolarized deuterons depends on the electromagnetic and weak form factors of a deuteron, whereas in the Weinberg-Salam model it does not depend on the structure of the deuteron. In the Weinberg-Salam model the asymmetry is independent on the T-violating form factors of the deuteron, whereas such a dependence is present in the vector-like theories
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
Experimental study of intensive electron beam scattering in melting channel
International Nuclear Information System (INIS)
Balagura, V.S.; Kurilko, V.I.; Safronov, B.G.
1988-01-01
Multiple scattering of an intensive electron beam at 28 keV energy passing through a melting channel in iron targets is experimentally studied. The dependence of scattering on the melting current value is established. The material density in the channel on the basis of the binary collision method is evaluated. It is shown that these density values are of three orders less than the estimations made on the basis of the data on energy losses of electrons in the channel. 6 refs.; 4 figs
Optical-potential model for electron-atom scattering
International Nuclear Information System (INIS)
Callaway, J.; Oza, D.H.
1985-01-01
It is proposed that the addition of a matrix optical potential to a close-coupling calculation should lead to improved results in studies of electron-atom scattering. This procedure is described with use of a pseudostate expansion to evaluate the optical potential. The integro-differential equations are solved by a linear-algebraic method. As a test case, applications are made to electron-hydrogen scattering, and the results are compared with those obtained by other calculational procedures, and with experiment
Electron scattering and correlation structure of light nuclei
International Nuclear Information System (INIS)
Lodhi, M.A.K.
1976-01-01
It has been known for some time that the short-range correlations due to the repulsive part of the nuclear interaction is exhibited in the nuclear form factors as obtained from high energy electron scattering. In this work the harmonic oscillator basis functions are used. The nuclear form factors as obtained from elastic electron scattering are calculated, with Jastrow's technique by means of the cluster expansion of Iwamoto Yamada, in the Born approximation. The correlated wave function is given. The results for nuclear form factors calculated with the wave function are presented for some light nuclei. (Auth.)
Hybrid Theory of Electron-Hydrogenic Systems Elastic Scattering
Bhatia, A. K.
2007-01-01
Accurate electron-hydrogen and electron-hydrogenic cross sections are required to interpret fusion experiments, laboratory plasma physics and properties of the solar and astrophysical plasmas. We have developed a method in which the short-range and long-range correlations can be included at the same time in the scattering equations. The phase shifts have rigorous lower bounds and the scattering lengths have rigorous upper bounds. The phase shifts in the resonance region can be used to calculate very accurately the resonance parameters.
Study of Compton broadening due to electron-photon scattering
Directory of Open Access Journals (Sweden)
Srinivasa Rao M.
2010-01-01
Full Text Available We have investigated the effects of Compton broadening due to electron-photon scattering in hot stellar atmospheres. A purely electron-photon scattering media is assumed to have plane parallel geometry with an input radiation field localized on one side of the slab. The method is based on the discrete space theory of radiative transfer for the intensity of emitted radiation. The solution is developed to study the importance of scattering of radiation by free electrons in high temperature stellar atmospheres which produces a brodening and shift in spectral lines because of the Compton effect and the Doppler effect arising from mass and thermal motions of scattering electrons. It is noticed that the Comptonized spectrum depends on three parameters: the optical depth of the medium, the temperature of the thermal electrons and the viewing angle. We also showed that the Compton effect produces red shift and asymmetry in the line. These two effects increase as the optical depth increases. It is also noticed that the emergent specific intensities become completely asymmetric for higher optical depths.
Study of Compton Broadening Due to Electron-Photon Scattering
Directory of Open Access Journals (Sweden)
Srinivasa Rao, M.
2010-06-01
Full Text Available We have investigated the effects of Compton broadening due to electron-photon scattering in hot stellar atmospheres. A purely electron-photon scattering media is assumed to have plane parallel geometry with an input radiation field localized on one side of the slab. The method is based on the discrete space theory of radiative transfer for the intensity of emitted radiation.The solution is developed to study the importance of scattering of radiation by free electrons in high temperature stellar atmospheres which produces a brodening and shift in spectral lines because of the Compton effect and the Doppler effect arising from mass and thermal motions of scattering electrons.It is noticed that the Comptonized spectrum depends on three parameters: the optical depth of the medium, the temperature of the thermal electrons and the viewing angle.We also showed that the Compton effect produces red shift and asymmetry in the line. These two effects increase as the optical depth increases. It is also noticed that the emergent specific intensities become completely asymmetric for higher optical depths.
Directory of Open Access Journals (Sweden)
Manvir S. Kushwaha
2012-09-01
Full Text Available The most fundamental approach to an understanding of electronic, optical, and transport phenomena which the condensed matter physics (of conventional as well as nonconventional systems offers is generally founded on two experiments: the inelastic electron scattering and the inelastic light scattering. This work embarks on providing a systematic framework for the theory of inelastic electron scattering and of inelastic light scattering from the electronic excitations in GaAs/Ga1−xAlxAs quantum wells. To this end, we start with the Kubo's correlation function to derive the generalized nonlocal, dynamic dielectric function, and the inverse dielectric function within the framework of Bohm-Pines’ random-phase approximation. This is followed by a thorough development of the theory of inelastic electron scattering and of inelastic light scattering. The methodological part is then subjected to the analytical diagnoses which allow us to sense the subtlety of the analytical results and the importance of their applications. The general analytical results, which know no bounds regarding, e.g., the subband occupancy, are then specified so as to make them applicable to practicality. After trying and testing the eigenfunctions, we compute the density of states, the Fermi energy, the full excitation spectrum made up of intrasubband and intersubband – single-particle and collective (plasmon – excitations, the loss functions for all the principal geometries envisioned for the inelastic electron scattering, and the Raman intensity, which provides a measure of the real transitions induced by the (laser probe, for the inelastic light scattering. It is found that the dominant contribution to both the loss peaks and the Raman peaks comes from the collective (plasmon excitations. As to the single-particle peaks, the analysis indicates a long-lasting lack of quantitative comparison between theory and experiments. It is inferred that the inelastic electron
Electron-translation effects in heavy-ion scattering
International Nuclear Information System (INIS)
Heinz, U.; Greiner, W.; Mueller, B.
1981-01-01
The origin and importance of electron-translation effects within a molecular description of electronic excitations in heavy-ion collisions is investigated. First, a fully consistent quantum-mechanical description of the scattering process is developed; the electrons are described by relativistic molecular orbitals, while the nuclear motion is approximated nonrelativistically. Leaving the quantum-mechanical level by using the semiclassical approximation for the nuclear motion, a set of coupled differential equations for the occupation amplitudes of the molecular orbitals is derived. In these coupled-channel equations the spurious asymptotic dynamical couplings are corrected for by additional matrix elements stemming from the electron translation. Hence, a molecular description of electronic excitations in heavy-ion scattering has been achieved, which is free from the spurious asymptotic couplings of the conventional perturbated stationary-state approach. The importance of electron-translation effects for continuum electrons and positrons is investigated. To this end an algorithm for the description of continuum electrons is proposed, which for the first time should allow for the calculation of angular distributions for delta electrons. Finally, the practical consequences of electron-translation effects are studied by calculating the corrected coupling matrix elements for the Pb-Cm system and comparing the corresponding K-vacancy probabilities with conventional calculations. We critically discuss conventional methods for cutting off the coupling matrix elements in coupled-channel calculations
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
Electron scattering off short-lived radioactive nuclei
International Nuclear Information System (INIS)
Wang, S.; Emoto, T.; Furukawa, Y.
2009-01-01
We have established a novel method which make electron scattering off short-lived radioactive nuclei come into being. This novel method was named SCRIT (Self-Confining RI ion Target). It was based on the well known "ion trapping" phenomenon in electron storage rings. Stable nucleus, 133 Cs, was used as target nucleus in the R&D experiment. The luminosity of interaction between stored electrons and Cs ions was about 1.02(0.06) × 10 26 cm -2 s -1 at beam current around 80 mA. The angular distribution of elastically scattered electrons from trapped Cs ions was measured. And an online luminosity monitor was used to monitor the change of luminosity during the experiment. (author)
Electronic properties of Be and Al by Compton scattering technique
International Nuclear Information System (INIS)
Aguiar, J.C.; Di Rocco, H.O.
2011-01-01
In this work, electronic properties of beryllium and aluminum are examined by using Compton scattering technique. The method is based on the irradiation of samples using a beam narrow of mono- energetic photons of 59.54 keV product of radioactive decay of Am -241 . Scattered radiation is collected by a high resolution semiconductor detector positioned at an angle of 90°. The measured spectrum is commonly called Compton profile and contains useful information about the electronic structure of the material. The experimental results are compared with theoretical calculations such as density functional theory showing a good agreement. However, these results show some discrepancies with many libraries used in codes such as Monte Carlo simulation. Since these libraries are based on the values tabulated by Biggs, Mendelsohn and Mann 1975 thus overestimating the scattered radiation on the material. (authors) [es
Resonant inelastic scattering of quasifree electrons on ions
International Nuclear Information System (INIS)
Grabbe, S.
1994-01-01
Several studies of resonant-transfer excitation (RTE) have been reported in ion-atom collisions where the doubly excited autoionizing states are produced. Such a complex collision can be approximated as the scattering of quasifree electrons of the target from the projectile ion. Most of the investigations have been restricted to the deexcitation of the autoionizing states to the ground state by Auger electron emission. It has been shown that there is a strong interference between the elastic scattering amplitude and the resonance amplitude. The authors present here the cases where the corresponding interference is between the inelastic scattering and the resonance process. Recent work on 3 ell 3 ell ' resonances that decay predominantly to n=2 states will be presented for C 5+ -molecular hydrogen collisions
Threshold behavior in electron-atom scattering
International Nuclear Information System (INIS)
Sadeghpour, H.R.; Greene, C.H.
1996-01-01
Ever since the classic work of Wannier in 1953, the process of treating two threshold electrons in the continuum of a positively charged ion has been an active field of study. The authors have developed a treatment motivated by the physics below the double ionization threshold. By modeling the double ionization as a series of Landau-Zener transitions, they obtain an analytical formulation of the absolute threshold probability which has a leading power law behavior, akin to Wannier's law. Some of the noteworthy aspects of this derivation are that the derivation can be conveniently continued below threshold giving rise to a open-quotes cuspclose quotes at threshold, and that on both sides of the threshold, absolute values of the cross sections are obtained
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
MAGNETIC SPECTROMETER DESIGN FOR ELECTRON SCATTERING ABOVE 1 Bev
Energy Technology Data Exchange (ETDEWEB)
Schopper, H.
1963-06-15
Design considerations are discussed for magnetic spectrometer electron scattering investigations with the higher energy (above 1 Bev) electron sources which are being developed. The spectrometers are to be used to discriminate between elastic and inelastic processes. A momentum resolution of the order of one per cent is required for these experiments. Various spectrometers are compared according to their optical properties and the number of magnets they consist of. (R.E.U.)
Observation of Electronic Raman Scattering in Metallic Carbon Nanotubes
Czech Academy of Sciences Publication Activity Database
Farhat, H.; Berciaud, S.; Kalbáč, Martin; Saito, R.; Heinz, T. F.; Dresselhaus, M. S.; Kong, J.
2011-01-01
Roč. 107, č. 15 (2011), s. 157401 ISSN 0031-9007 R&D Projects: GA MŠk ME09060 Institutional research plan: CEZ:AV0Z40400503 Keywords : spectroscopy * electronic Raman scattering * metallic carbon nanotubes Subject RIV: CG - Electrochemistry Impact factor: 7.370, year: 2011
On neutrino and antineutrino scattering by electrons, and by partons
Bell, J S
1975-01-01
Assuming a non-derivative point interaction, and Born approximation, there are some simple relations between neutrino and antineutrino scattering on electrons or partons. They have been observed already, for some special cases, in the results of explicit calculations. Here they are obtained from simple and general considerations. (8 refs).
Properties of the scattering amplitude for electron-atom collisions
International Nuclear Information System (INIS)
Combes, J.M.; Tip, A.
1983-02-01
For the scattering of an electron by an atom finiteness of the amplitude at non threshold energies is proved in the framework of the N-body Schroedinger equation. It is also shown that both the direct and exchange amplitudes have analytic continuations for complex values of incident momentum, with pole or cut singularities on the imaginary axis
On neutrino and antineutrino scattering by electrons, and by partons
International Nuclear Information System (INIS)
Bell, J.S.; Dass, G.V.
1975-09-01
Assuming a non-derivative point interaction, and Born approximation, there are some simple relations between neutrino and antineutrino scattering on electrons or partons. They have been observed already, for some special cases, in the results of explicit calculations. Here they are obtained from simple general considerations. (author)
Electron scattering from CO in the 2Pi resonance region
International Nuclear Information System (INIS)
Buckman, S.J.; Lohmann, B.
1986-01-01
The total cross section for electron scattering from CO in the energy range 0.5--5 eV has been measured with use of a time-of-flight spectrometer. This energy region encompasses the 2 π shape resonance, and a comparison is made with other experimental and theoretical results with regard to the magnitude and position of this structure
Quasielastic electron scattering: effect of relativistic nuclear potentials
International Nuclear Information System (INIS)
Do Dang, G.; Nguyen Van Giai.
1983-11-01
It is shown that a solution to the difficulty encountered in reproducing simultaneously the experimental longitudinal and transverse response functions deduced from deep inelastic electron scattering may be found in a consistent treatment of the electromagnetic interaction in a Dirac equation in which Lorentz scalar and vector potentials are explicitly introduced. Results for 12 C and 40 Ca are given and compared with experiments
Experimental study of the deuteron induced deuteron break-up at low energy
Energy Technology Data Exchange (ETDEWEB)
Cocu, F.; Ambrosino, G.; Guerreau, D.; Lachkar, J.
1974-07-01
The quasi-free scattering process has been studied from the d + D -> n + p + D reaction at 6 deuteron energies between 6.77 MeV to 11.7 MeV in steps of 1 MeV. Coincident events between neutron and charged-particle pulses (emitted protons or deuterons) have been recorded at angles of {theta}{sub p} = {theta}{sub d} = 19 deg 5 and {theta}{sub n} = 330 deg. Some calculations using the plane wave approximation account for the shape of the experimental cross sections but not for their magnitude. Two kinds of nucleon-nucleon forces are used and discussed.
Deuteron color degrees of freedom and deuteron break-up at high energy
International Nuclear Information System (INIS)
Kobushkin, A.P.
1992-01-01
Deuteron break-up reactions are analysed from a QCD-motivated point of view. Production of a nucleon with hard momentum is considered as a result of high gluon exchange between three quark clusters in hidden-color component of deuteron wave function. It is shown that the model reproduces well the nucleon momentum distribution extracted from (d,p)-reaction at high energy as well as the tensor analysing powers T 20 of this reaction and of the reaction of elastic pd-backward scattering. 19 refs.; 2 figs.; 1 tab. (author)
Electrons scattered inside small dust grains of various materials
International Nuclear Information System (INIS)
Richterova, Ivana; Beranek, Martin; Pavlu, Jiri; Nemecek, Zdenek; Safrankova, Jana
2010-01-01
The dust grain charge in an electron beam is given by a difference in numbers of electrons that fall onto the grain and those leaving it. Electrons with energies exceeding 1 keV can penetrate through submicron-sized dust grains. If the grain is small enough, a yield of these electrons reaches unity but they leave a part of their energy inside the grain and this energy excites secondary electrons. The paper presents a hybrid Monte Carlo code that simulates paths of the primary electrons inside a spherical grain and provides the yield of scattered electrons and their energy spectrum as a function of the grain size and material. This code is based on the Richterovaet al. [Phys. Rev. B 74, 235430 (2006)] model but it includes several corrections important for light materials like carbon or ice. The model was verified using experimental results obtained on large planar samples. For spherical samples, we have found that the yield of scattered electrons reaches unity for 50 nm Au grains illuminated by 5 keV electrons, whereas the same effect can be observed on ≅1000 nm carbon grains.
A P + DEUTERON PROTON POLARIMETER AT 200 MEV.
Energy Technology Data Exchange (ETDEWEB)
HUANG,H.; ROSER,T.; ZELENSKI,A.; KURITA,K.; STEPHENSON,E.; TOOLE,R.
2002-06-02
There has been concern about the analyzing power of the p-Carbon polarimeter at the end of 200 MeV LINAC of BNL. A new polarimeter based on proton-deuteron scattering was installed and we have repeated the calibration of proton-Carbon scattering at 12 degrees and 200 MeV against proton-deuteron scattering. The result is consistent with the value of A=0.62 now used to measure the beam polarization at the end of the LINAC.
Electron-electron scattering in linear transport in two-dimensional systems
DEFF Research Database (Denmark)
Hu, Ben Yu-Kuang; Flensberg, Karsten
1996-01-01
We describe a method for numerically incorporating electron-electron scattering in quantum wells for small deviations of the distribution function from equilibrium, within the framework of the Boltzmann equation. For a given temperature T and density n, a symmetric matrix needs to be evaluated only...... once, and henceforth it can be used to describe electron-electron scattering in any Boltzmann equation linear-response calculation for that particular T and n. Using this method, we calculate the distribution function and mobility for electrons in a quantum well, including full finite...
Measurement of the deuteron elastic structure functions up to large momentum transfers
International Nuclear Information System (INIS)
Jager, K. De
1999-01-01
The cross section for elastic electron-deuteron scattering was measured in JLab experiment 91-026. The deuteron elastic structure functions A(Q 2 ) and B(Q 2 ) have been extracted from this data. The final results for the ''electric'' structure function A(Q 2 ), in the range of 0.7 less than or equal to Q 2 less than or equal to 6.0 (GeV/c) 2 are presented. Preliminary results for the ''magnetic'' structure function B(Q 2 ) are presented in the range of 0.7 less than or equal to Q 2 less than or equal to 1.35 (GeV/c) 2 . These data are compared with theoretical predictions of both meson-nucleon and quark-gluon based models
Electron enhanced Raman scattering and its applications in solution chemistry
International Nuclear Information System (INIS)
Yui, Hiroharu
2007-01-01
The present review describes a new enhancement technique for Raman scattering in aqueous solutions. Raman scattering spectroscopy has an inherent ability to distinguish between molecules with great similarity and provides useful information on local physical and chemical environments at their functional groups' level. Since the Raman scattering signals from water molecules are quite weak, Raman spectroscopy has great advantage for detection or discrimination of a trace amount of analytes in aqueous environments. However, Raman scattering cross-sections are inherently small and it generally requires high power excitation and long acquisition times to obtain high-quality Raman spectra. These conditions create disadvantages for the analyses for living cells and real-time monitoring for environmental analyses. Here, I describe a new Raman enhancement technique, namely electron enhanced Raman scattering (EERS)', where artificially generated electrons additionally affect the polarizability of target molecular systems and enhance their inherent Raman cross-section. Principles of the EERS and its applications to aqueous solution are presented. (author)
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)
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
NESKA, Electron and Positron Scattering from Point Nuclei
International Nuclear Information System (INIS)
Idoeta, R.; Legarda, F.
2002-01-01
1 - Description of program or function: The Mott's differential cross section for the scattering of electrons and positrons by point nuclei without screening is calculated for any energy, atomic number and angle of scattering. 2 - Method of solution: We have summed the conditionally convergent series appearing in Mott's cross section using two consecutive transformations: the one of Yennie, Ravenhall and Wilson and that of Euler till we have seven times six significant figures repeated in the ratio of the Mott cross section to the classical Rutherford cross section. 3 - Restrictions on the complexity of the problem: Those appearing in the use of Mott's cross section for unscreened point nuclei
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
Electron states and electron Raman scattering in semiconductor double cylindrical quantum well wire
International Nuclear Information System (INIS)
Munguía-Rodríguez, M; Riera, R; Betancourt-Riera, Ri; Betancourt-Riera, Re; Nieto Jalil, J M
2016-01-01
The differential cross section for an electron Raman scattering process in a semiconductor GaAs/AlGaAs double quantum well wire is calculated, and expressions for the electronic states are presented. The system is modeled by considering T = 0 K and also with a single parabolic conduction band, which is split into a subband system due to the confinement. The gain and differential cross-section for an electron Raman scattering process are obtained. In addition, the emission spectra for several scattering configurations are discussed, and interpretations of the singularities found in the spectra are given. The electron Raman scattering studied here can be used to provide direct information about the efficiency of the lasers. (paper)
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
International Nuclear Information System (INIS)
Gladkikh, P.I.; Telegin, Yu.N.; Karnaukhov, I.M.
2002-01-01
The feasibility of the development of intense X-ray sources based on Compton scattering in laser-electron storage rings is discussed. The results of the electron beam dynamics simulation involving Compton and intrabeam scattering are presented
Gladkikh, P I; Karnaukhov, I M
2002-01-01
The feasibility of the development of intense X-ray sources based on Compton scattering in laser-electron storage rings is discussed. The results of the electron beam dynamics simulation involving Compton and intrabeam scattering are presented.
International Nuclear Information System (INIS)
Kurennoy, S.S.; O'Hara, J.F.; Rybarcyk, L.J.
2008-01-01
We are developing a compact deuteron-beam accelerator up to the deuteron energy of a few MeV based on room-temperature inter-digital H-mode (IH) accelerating structures with the transverse beam focusing using permanent-magnet quadrupoles (PMQ). Combining electromagnetic 3-D modeling with beam dynamics simulations and thermal-stress analysis, we show that IHPMQ structures provide very efficient and practical accelerators for light-ion beams of considerable currents at the beam velocities around a few percent of the speed of light. IH-structures with PMQ focusing following a short RFQ can also be beneficial in the front end of ion linacs.
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
Coherent Electron Scattering Captured by an Attosecond Quantum Stroboscope
International Nuclear Information System (INIS)
Mauritsson, J.; Johnsson, P.; Mansten, E.; Swoboda, M.; Ruchon, T.; L'Huillier, A.; Schafer, K. J.
2008-01-01
We demonstrate a quantum stroboscope based on a sequence of identical attosecond pulses that are used to release electrons into a strong infrared (IR) laser field exactly once per laser cycle. The resulting electron momentum distributions are recorded as a function of time delay between the IR laser and the attosecond pulse train using a velocity map imaging spectrometer. Because our train of attosecond pulses creates a train of identical electron wave packets, a single ionization event can be studied stroboscopically. This technique has enabled us to image the coherent electron scattering that takes place when the IR field is sufficiently strong to reverse the initial direction of the electron motion causing it to rescatter from its parent ion
Laser-Compton Scattering as a Potential Electron Beam Monitor
International Nuclear Information System (INIS)
Chouffani, K.; Wells, D.; Harmon, F.; Lancaster, G.; Jones, J.
2002-01-01
LCS experiments were carried out at the Idaho Accelerator Center (IAC); sharp monochromatic x-ray lines were observed. These are produced using the so-called inverse Compton effect, whereby optical laser photons are collided with a relativistic electron beam. The back-scattered photons are then kinematically boosted to keV x-ray energies. We have first demonstrated these beams using a 20 MeV electron beam collided with a 100 MW, 7 ns Nd; YAG laser. We observed narrow LCS x-ray spectral peaks resulting from the interaction of the electron beam with the Nd; YAG laser second harmonic (532 nm). The LCS x-ray energy lines and energy deviations were measured as a function of the electron beam energy and energy-spread respectively. The results showed good agreement with the predicted valves. LCS could provide an excellent probe of electron beam energy, energy spread, transverse and longitudinal distribution and direction
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
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
Generalized Hartree-Fock method for electron-atom scattering
International Nuclear Information System (INIS)
Rosenberg, L.
1997-01-01
In the widely used Hartree-Fock procedure for atomic structure calculations, trial functions in the form of linear combinations of Slater determinants are constructed and the Rayleigh-Ritz minimum principle is applied to determine the best in that class. A generalization of this approach, applicable to low-energy electron-atom scattering, is developed here. The method is based on a unique decomposition of the scattering wave function into open- and closed-channel components, so chosen that an approximation to the closed-channel component may be obtained by adopting it as a trial function in a minimum principle, whose rigor can be maintained even when the target wave functions are imprecisely known. Given a closed-channel trial function, the full scattering function may be determined from the solution of an effective one-body Schroedinger equation. Alternatively, in a generalized Hartree-Fock approach, the minimum principle leads to coupled integrodifferential equations to be satisfied by the basis functions appearing in a Slater-determinant representation of the closed-channel wave function; it also provides a procedure for optimizing the choice of nonlinear parameters in a variational determination of these basis functions. Inclusion of additional Slater determinants in the closed-channel trial function allows for systematic improvement of that function, as well as the calculated scattering parameters, with the possibility of spurious singularities avoided. Electron-electron correlations can be important in accounting for long-range forces and resonances. These correlation effects can be included explicitly by suitable choice of one component of the closed-channel wave function; the remaining component may then be determined by the generalized Hartree-Fock procedure. As a simple test, the method is applied to s-wave scattering of positrons by hydrogen. copyright 1997 The American Physical Society
Low-energy positron and electron scattering from nitrogen dioxide
International Nuclear Information System (INIS)
Chiari, Luca; Brunger, M J; Zecca, Antonio; García, Gustavo; Blanco, Francisco
2013-01-01
Total cross section (TCS) measurements for positron scattering from nitrogen dioxide (NO 2 ) are presented in the energy range 0.2–40 eV. The TCS, the elastic integral and differential cross sections, and the integral cross section accounting of all the inelastic processes (including positronium formation) have also been computed using the independent atom model with screening corrected additivity rule (IAM-SCAR) for incident energies from 1 to 1000 eV. A qualitative level of agreement is found between the present TCS experiment and theory at the common energies. As no previous measurements or calculations for positron–NO 2 scattering exist in the literature, we also computed the TCS for electron collisions with NO 2 employing the IAM-SCAR method. A comparison of those results to the present positron cross sections and the earlier electron-impact data and calculations is provided. To investigate the role that chemical substitution plays in positron scattering phenomena, we also compare the present positron–NO 2 data with the TCSs measured at the University of Trento for positron scattering from N 2 O and CO 2 . (paper)
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.
Total cross sections for positron and electron scattering from pyrimidine
International Nuclear Information System (INIS)
Zecca, A; Chiari, L; Trainotti, E; GarcIa, G; Blanco, F; Brunger, M J
2010-01-01
In this paper we report original measurements of total cross sections for positron scattering from the important biomolecule pyrimidine. The energy range of these measurements was 0.3-45 eV, while the energy resolution was ∼260 meV. In addition, we report theoretical results, calculated within the independent atom-screened additivity rule (IAM-SCAR) formalism, for the corresponding electron impact total cross sections. In that case the energy range is 1-10 000 eV. Total cross sections are very important input data for codes that seek to simulate charged-particle tracks in matter, as they define the mean-free path between collisions. As the present data and computations are to the best of our knowledge the first total cross sections to be reported for either positron or electron scattering from pyrimidine, they fill an important void in our available knowledge in the literature.
Recent single ARM electron scattering experiments at Saclay
International Nuclear Information System (INIS)
Frois, B.
1981-07-01
Some recent electron scattering experiments at intermediate energies performed at the Saclay linear accelerator (ALS) are presented. First the definitive results of the measurements of the size of valence orbits by magnetic elastic electron scattering are discussed and followed by an overview of the study of charge distributions in closed shell nuclei. These results are among the most stringent experimental tests of nuclear theory because they probe without ambiguity the shape of nuclei. Then, it is shown how the details of the transition densities of the first excited states of 152 Sm have been brought out by very high momentum transfer experiments. Finally, the results of the investigation of mesonic degrees of freedom in deuterium and helium-3 are presented
Inverse electronic scattering by Green's functions and singular values decomposition
International Nuclear Information System (INIS)
Mayer, A.; Vigneron, J.-P.
2000-01-01
An inverse scattering technique is developed to enable a sample reconstruction from the diffraction figures obtained by electronic projection microscopy. In its Green's functions formulation, this technique takes account of all orders of diffraction by performing an iterative reconstruction of the wave function on the observation screen. This scattered wave function is then backpropagated to the sample to determine the potential-energy distribution, which is assumed real valued. The method relies on the use of singular values decomposition techniques, thus providing the best least-squares solutions and enabling a reduction of noise. The technique is applied to the analysis of a two-dimensional nanometric sample that is observed in Fresnel conditions with an electronic energy of 25 eV. The algorithm turns out to provide results with a mean relative error of the order of 5% and to be very stable against random noise
Magnetic spectrometer of the DEUTERON-2 set-up
International Nuclear Information System (INIS)
Ajvazyan, R.V.; Alanakyan, K.V.; Amaryan, M.J.
1989-01-01
A magnetic spectrometer of the two-arm DEUTERON-2 set-up of the Erevan Physical Institute is described. It is shown that the rejection factor for electrons and pions is 10 -2 - 10 -3 . The positively charged particles in the momentum range up to 1.5 GeV/c are identified by momentum and time-of-flight measurements. The main characteristics of the spectrometer are: momentum and angular acceptance δp/p = 46%, Δθ = 4 deg, solid angle ΔΩ = 2.75 msr, momentum resolution δp/p = 1.5%, angular resolutions δθ = 0.6 deg, δφ = 2 deg. The intervals of measured momentum and the polar scattering anlge are 0.5-3 GeV/c and 10-30 deg, 68-90 deg respectively. 7 refs.; 11 figs
Parity Violation in Atoms and Polarized Electron Scattering
Bouchiat, Marie-Anne; PAVI'97
1999-01-01
This work is an extensive review of the advances in the field of parity violation experiments in electron scattering at high energy and and in atomic physics. The results are a challenge to the standard electroweak theory and the understanding of hadron structure. The theoretical framework is presented at a pedagogical level, experiments and future projects are reviewed, and the results and their interpretation are discussed.
Magnetic electron scattering from deuterium at low-momentum transfer
International Nuclear Information System (INIS)
Jones, E.C. Jr.; Bendel, W.L.; Fagg, L.W.; Lindgren, R.A.
1980-01-01
The elastic and inelastic cross sections of deuterium for 56.4 MeV electrons scattered at 180 0 , have been measured up to an excitation energy of 19 MeV. The experimental cross sections are compared with those calculated by Miller, by Durand, and by Arenhoevel and Fabian, and also with the sum rules of O'Connell. The results indicate that the contribution of meson exchange currents at this low-momentum transfer is significant
180° electron scattering at the S-DALINAC
International Nuclear Information System (INIS)
Neumann-Cosel, Peter von
2016-01-01
The contribution discusses features of the 180deg system at the S-DALINAC its experimental program on transverse electron scattering with emphasis on topics of relevance for the description of neutrino interaction with nuclei. Examples discussed include the quenching of spin-isospin modes common to vector and axial coupling and M1 strength distributions for the modeling of neutral-current neutrino-nucleus interactions. (author)
Electron scattering in graphene with adsorbed NaCl nanoparticles
Energy Technology Data Exchange (ETDEWEB)
Drabińska, Aneta, E-mail: Aneta.Drabinska@fuw.edu.pl; Kaźmierczak, Piotr; Bożek, Rafał; Karpierz, Ewelina; Wysmołek, Andrzej; Kamińska, Maria [Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw (Poland); Wołoś, Agnieszka [Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw (Poland); Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw (Poland); Pasternak, Iwona; Strupiński, Włodek [Institute of Electronic Materials Technology, Wólczyńska 133, 01-919 Warsaw (Poland); Krajewska, Aleksandra [Institute of Electronic Materials Technology, Wólczyńska 133, 01-919 Warsaw (Poland); Institute of Optoelectronics, Military University of Technology, Kaliskiego 2, 00-908 Warsaw (Poland)
2015-01-07
In this work, the results of contactless magnetoconductance and Raman spectroscopy measurements performed for a graphene sample after its immersion in NaCl solution were presented. The properties of the immersed sample were compared with those of a non-immersed reference sample. Atomic force microscopy and electron spin resonance experiments confirmed the deposition of NaCl nanoparticles on the graphene surface. A weak localization signal observed using contactless magnetoconductance showed the reduction of the coherence length after NaCl treatment of graphene. Temperature dependence of the coherence length indicated a change from ballistic to diffusive regime in electron transport after NaCl treatment. The main inelastic scattering process was of the electron-electron type but the major reason for the reduction of the coherence length at low temperatures was additional, temperature independent, inelastic scattering. We associate it with spin flip scattering, caused by NaCl nanoparticles present on the graphene surface. Raman spectroscopy showed an increase in the D and D′ bands intensities for graphene after its immersion in NaCl solution. An analysis of the D, D′, and G bands intensities proved that this additional scattering is related to the decoration of vacancies and grain boundaries with NaCl nanoparticles, as well as generation of new on-site defects as a result of the decoration of the graphene surface with NaCl nanoparticles. The observed energy shifts of 2D and G bands indicated that NaCl deposition on the graphene surface did not change carrier concentration, but reduced compressive biaxial strain in the graphene layer.
Electron scattering in graphene with adsorbed NaCl nanoparticles
International Nuclear Information System (INIS)
Drabińska, Aneta; Kaźmierczak, Piotr; Bożek, Rafał; Karpierz, Ewelina; Wysmołek, Andrzej; Kamińska, Maria; Wołoś, Agnieszka; Pasternak, Iwona; Strupiński, Włodek; Krajewska, Aleksandra
2015-01-01
In this work, the results of contactless magnetoconductance and Raman spectroscopy measurements performed for a graphene sample after its immersion in NaCl solution were presented. The properties of the immersed sample were compared with those of a non-immersed reference sample. Atomic force microscopy and electron spin resonance experiments confirmed the deposition of NaCl nanoparticles on the graphene surface. A weak localization signal observed using contactless magnetoconductance showed the reduction of the coherence length after NaCl treatment of graphene. Temperature dependence of the coherence length indicated a change from ballistic to diffusive regime in electron transport after NaCl treatment. The main inelastic scattering process was of the electron-electron type but the major reason for the reduction of the coherence length at low temperatures was additional, temperature independent, inelastic scattering. We associate it with spin flip scattering, caused by NaCl nanoparticles present on the graphene surface. Raman spectroscopy showed an increase in the D and D′ bands intensities for graphene after its immersion in NaCl solution. An analysis of the D, D′, and G bands intensities proved that this additional scattering is related to the decoration of vacancies and grain boundaries with NaCl nanoparticles, as well as generation of new on-site defects as a result of the decoration of the graphene surface with NaCl nanoparticles. The observed energy shifts of 2D and G bands indicated that NaCl deposition on the graphene surface did not change carrier concentration, but reduced compressive biaxial strain in the graphene layer
Forming of electron beams from a betatron by foils scatterers
Energy Technology Data Exchange (ETDEWEB)
Kozlov, A P; Shishov, V A [N.N. Petrov Research Inst. of Oncology, Leningrad (USSR). Laboratory of High Energics
1976-12-01
The technique of forming electron beams by one scattering foil and one compensating foil is discussed. This method provides a means for producing large-size uniform dose distributions with much smaller losses in dose rate as compared with conventional beam forming by ine foil. Moreover, the energy losses involved in this process and the background of concomitant bremsstrahlung are much less. A techinque of calculation to determine approximate parameters of the compensating foils is described.
Electron scattering in the presence of an intense electromagnetic field
International Nuclear Information System (INIS)
Mohan, M.; Chand, P.
1977-03-01
The general theory of electron scattering in the presence of an external electromagnetic field, provided by an intense laser beam, accompanied by absorption of n photons, each with energy hω, is discussed. The calculation leads to many summations over intermediate states. A general method for exactly evaluating several sums is described in detail. Numerical results show that the cross-section varies with intensity in a power law fashion
Electron scattering. Lectures given at Argonne National Laboratory
International Nuclear Information System (INIS)
Walecka, J.D.
1984-01-01
This report is an almost verbatim copy of lectures on Electron Scattering given at Argonne National Laboratory in the Fall of 1982 by John Dirk Walecka. Professor Walecka was an Argonne Fellow in the Physics Division from October 1982 to January 1983. Broad headings include general considerations, coincidence cross section (e,e'x), quantum electrodynamics and radiative corrections, unification of electroweak interactions, relativistic models of nuclear structure, electroproduction of pions and nucleon resonances, and deep inelastic (e,e')
Neutron production by deuteron breakup on 4He
International Nuclear Information System (INIS)
Schmidt, D.
1994-10-01
Neutron spectra of the deuteron breakup on 4 He have been measured at eight deuteron incident energies between 4.7 MeV and 12.1 MeV using the TOF method. The measurements carried out at angles of 0 deg, 5 deg and 10 deg were completed by measurements at 2.5 deg and 7.5 deg at some energies. The cross sections for these angles were reliably interpolated for the other energies. The normalization to absolute cross sections was carried out by reference to the well known data of the DD reaction. When a relative energy scale is introduced the spectral shape is almost angle-independent. It is shown that the use of the deuteron breakup on 4 He can considerably refine the correction for the deuteron breakup on deuterium in scattering experiments made with Monte Carlo simulations. (orig.)
Dual scattering foil design for poly-energetic electron beams
International Nuclear Information System (INIS)
Kainz, K K; Antolak, J A; Almond, P R; Bloch, C D; Hogstrom, K R
2005-01-01
The laser wakefield acceleration (LWFA) mechanism can accelerate electrons to energies within the 6-20 MeV range desired for therapy application. However, the energy spectrum of LWFA-generated electrons is broad, on the order of tens of MeV. Using existing laser technology, the therapeutic beam might require a significant energy spread to achieve clinically acceptable dose rates. The purpose of this work was to test the assumption that a scattering foil system designed for a mono-energetic beam would be suitable for a poly-energetic beam with a significant energy spread. Dual scattering foil systems were designed for mono-energetic beams using an existing analytical formalism based on Gaussian multiple-Coulomb scattering theory. The design criterion was to create a flat beam that would be suitable for fields up to 25 x 25 cm 2 at 100 cm from the primary scattering foil. Radial planar fluence profiles for poly-energetic beams with energy spreads ranging from 0.5 MeV to 6.5 MeV were calculated using two methods: (a) analytically by summing beam profiles for a range of mono-energetic beams through the scattering foil system, and (b) by Monte Carlo using the EGS/BEAM code. The analytic calculations facilitated fine adjustments to the foil design, and the Monte Carlo calculations enabled us to verify the results of the analytic calculation and to determine the phase-space characteristics of the broadened beam. Results showed that the flatness of the scattered beam is fairly insensitive to the width of the input energy spectrum. Also, results showed that dose calculated by the analytical and Monte Carlo methods agreed very well in the central portion of the beam. Outside the useable field area, the differences between the analytical and Monte Carlo results were small but significant, possibly due to the small angle approximation. However, these did not affect the conclusion that a scattering foil system designed for a mono-energetic beam will be suitable for a poly
Electron inelastic scattering by compound nuclei and giant multipole resonances
International Nuclear Information System (INIS)
Dzhavadov, A.V.; Mukhtarov, A.I.; Mirabutalybov, M.M.
1980-01-01
Multipole giant resonances in heavy nuclei have been investigated with the application of the Danos-Greiner dynamic collective theory to the Tassi model. The monopole giant resonance has been studied in 158 Gd, 166 Er, 184 W, 232 Th and 238 V nuclei at the incident electron energy E=200 MeV. Dependences of the form factor square of electron scattering by a 166 Er nucleus on the scattering angle obtained in the distorted-wave high-energy approximation (DWHEA) are presented. Giant dipole and quadrupole resonances in 60 Ni and 90 Zr nuclei have been studied. A comparison has been made of theoretical results obtained in the DWHEA for the dependence of the form factor square on the effective momentum transfer with the experimental data. The analysis of the obtained results led to the following conclusions. To draw a conclusion about the validity of one or another nuclear model and methods for calculating form factors, it is necessary to investigate, both theoretically and experimentally, electron scattering at great angles (THETA>=70 deg). To obtain a good agreement it is necessary to take account of the actual proton and neutron distributions in the ground state and their dynamic properties in an excited state [ru
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.
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.
Low-energy electron scattering from molecules, biomolecules and surfaces
Carsky, Petr
2011-01-01
Since the turn of the 21st century, the field of electron molecule collisions has undergone a renaissance. The importance of such collisions in applications from radiation chemistry to astrochemistry has flowered, and their role in industrial processes such as plasma technology and lighting are vital to the advancement of next generation devices. Furthermore, the development of the scanning tunneling microscope highlights the role of such collisions in the condensed phase, in surface processing, and in the development of nanotechnology.Low-Energy Electron Scattering from Molecules, Biomolecule
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.
Path-integral approach to resonant electron-molecule scattering
International Nuclear Information System (INIS)
Winterstetter, M.; Domcke, W.
1993-01-01
A path-integral formulation of resonant electron-molecule scattering is developed within the framework of the projection-operator formalism of scattering theory. The formation and decay of resonances is treated in real time as a quantum-mechanical electronic-tunneling process, modified by the coupling of the electronic motion with the nuclear degrees of freedom. It is shown that the electronic continuum can be summed over in the path-integral formulation, resulting formally in the path integral for an effective two-state system with coupling to vibrations. The harmonic-oscillator approximation is adopted for the vibrational motion in the present work. Approximation methods are introduced which render the numerical evaluation of the sum over paths feasible for up to ∼10 3 elementary time slices. The theory is numerically realized for simple but nontrivial models representing the 2 Π g d-wave shape resonance in e - +N 2 collisions and the 2 Σ u + p-wave shape resonance in e - +H 2 collisions, respectively. The accuracy of the path-integral results is assessed by comparison with exact numerical reference data for these models. The essential virtue of the path-integral approach is the fact that the computational effort scales at most linearly with the number of vibrational degrees of freedom. The path-integral method is thus well suited to treat electron collisions with polyatomic molecules and molecular aggregates
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.
Total cross sections for electron scattering with halocarbon molecules
Energy Technology Data Exchange (ETDEWEB)
Naghma, Rahla; Gupta, Dhanoj; Antony, Bobby, E-mail: bka.ism@gmail.com
2014-03-01
Highlights: • A quantum mechanical model to find elastic, inelastic and total CS by e{sup −} impact. • Spherical complex optical potential formalism is used to find total CS. • Result shows consistency and good agreement with previous data wherever available. • Maiden attempt to find CS for CH{sub 2}Br{sub 2}, CHBr{sub 3}, CBr{sub 4} and C{sub n}H{sub 2n+1}Cl (n = 2–4) molecules. • Interesting correlation observed between total CS and polarizability of the molecule. - Abstract: A theoretical study on electron collision with chlorinated methanes: CH{sub 2}Cl{sub 2} and CHCl{sub 3}, brominated methanes: CH{sub 2}Br{sub 2}, CHBr{sub 3} and CBr{sub 4} and some mono chloroalkanes: C{sub n}H{sub 2n+1}Cl (n = 2–4) molecules in gaseous ground state is undertaken to report elastic, inelastic and total cross sections in the 20–5000 eV energy range. The target molecule is represented as a sum of various scattering centres, which are assumed to scatter electrons independently. The spherical complex optical potential (SCOP) is formulated to represent the interaction dynamics between the electron and the constituent scattering centres. Using SCOP, the quantum mechanical scattering problem is solved through partial wave analysis. The results obtained for CH{sub 2}Cl{sub 2} and CHCl{sub 3} are compared with the available experimental and theoretical values. The elastic cross section for CBr{sub 4} shows satisfactory agreement with the previous available data. The cross sections for CH{sub 2}Br{sub 2}, CHBr{sub 3}, and C{sub n}H{sub 2n+1}Cl (n = 2–4) molecules presented in this work are reported for the first time.
Validity of the Glauber approximation with account of the deuteron quark structure
International Nuclear Information System (INIS)
Zakharov, B.G.; Kopeliovich, B.Z.
1985-01-01
Corrections to the hadron-deuteron elastic scattering amplitude due to the deuteron quark structore are calculated. The two-gluon pomeron model which provides a good description of the hadron-hardron scattering data has been used. It is shown that the Glauber approximation with elastic corrections provides with a good description of the data on the total and differential pd-scattering cross sections, if the admixture of the six-quark bag state in the deuteron S 6 wave function is small ( 6 approximately 0.8 fm
Electron scattering off hydrogen and deuterium at 500 and 600
International Nuclear Information System (INIS)
Atwood, W.B.
1975-06-01
The inelastic scattering of electrons for both protons and neutrons has been measured at scattering angles of fifty and sixty degrees and for incident energies between 6.5 GeV and 19.5 GeV. Elastic scattering from protons was also observed. The measurements were made at the Stanford Linear Accelerator Center using the 1.6-GeV spectrometer located in End Station A. The experimental techniques used in making the measurements are detailed. The resulting cross sections are large, indicative of a charged point-like substructure within the nucleon and match the extrapolation from previous measurements to the kinematic region to within forty percent. The measurements are found to be compatible with some existing theoretical expectations. The W 1 structure function is not found to ''scale'' in previously suggested scaling variables. The introduction of propagator scale breaking is investigated and shown to be compatible with the measurements. An alternative scaling variable is proposed in which W 1 is found to scale. The elastic scattering measurements are consistent with an inverse fourth power dependence on four-momenta transfer. The measured neutron-proton ratio is in agreement with previous measurements. (55 figures, 27 tables) (auth)
Electron scattering from 36Ar and 40Ar
International Nuclear Information System (INIS)
Finn, J.M.
1975-01-01
The argon isotopes, 36 Ar and 40 Ar, have been investigated using electron scattering at the high-resolution Linac facilities of the National Bureau of Standards. Both elastic scattering and scattering to low-lying states have been observed. A high-pressure, low-volume gas target cell was designed and developed for this experiment. The cell features a transmission geometry and has resolution comparable to solid targets. Spectra were obtained at incident beam energies ranging from 65 to 115 MeV at scattering angles of 92.5 0 and 110 0 . Values obtained for the rms charge radii are 3.327 +- 0.015 and 3.393 +- 0.015 fm for 36 Ar and 40 Ar respectively. A sensitive measurement was made of the difference in the two radii yielding a value of Δ r = 0.079 +- 0.006 fm. The inelastic levels observed are the 1.97 (2 + ) and 4.18 MeV (3 - ) levels in 36 Ar, and the 1.46 (2 + ), 2.52 (2 + ), 3.21 (2 + ), and 3.68 MeV (3 - ) levels in 40 Ar. A Tassie model analysis was made of the inelastic transitions in the DWBA approximation and transition strengths of these levels were extracted
Electron scattering from the ground state of mercury
International Nuclear Information System (INIS)
Fursa, D.; Bray, I.
2000-01-01
Full text: Close-coupling calculations have been performed for electron scattering from the ground state of mercury. We have used non-relativistic convergent close-coupling computer code with only minor modifications in order to account for the most prominent relativistic effects. These are the relativistic shift effect and singlet-triplet mixing. Very good agreement with measurements of differential cross sections for elastic scattering and excitation of 6s6p 1 P state at all energies is obtained. It is well recognised that a consistent approach to electron scattering from heavy atoms (like mercury, with nuclear charge Z=80) must be based on a fully relativistic Dirac equations based technique. While development of such technique is under progress in our group, the complexity of the problem ensures that results will not be available in the near future. On other hand, there is considerable interest in reliable theoretical results for electron scattering from heavy atoms from both applications and the need to interpret existing experimental data. This is particularly the case for mercury, which is the major component in fluorescent lighting devices and has been the subject of intense experimental study since nineteen thirties. Similarly to our approach for alkaline-earth atoms we use a model of two valence electrons above an inert Hartree-Fock core to describe the mercury atom. Note that this model does not account for any core excited states which are present in the mercury discrete spectrum. The major effect of missing core-excited states is substantial underestimation of the static dipole polarizability of the mercury ground state (34 a.u.) and consequent underestimation of the forward scattering elastic cross sections. We correct for this by adding in the scattering calculations a phenomenological polarization potential. In order to obtain correct ground state ionization energy for mercury one has to account for the relativistic shift effect. We model this
Pitch Angle Scattering of Energetic Electrons by Plasmaspheric Hiss Emissions
Tobita, M.; Omura, Y.; Summers, D.
2017-12-01
We study scattering of energetic electrons in pitch angles and kinetic energies through their resonance with plasmaspheric hiss emissions consisting of many coherent discrete whistler-mode wave packets with rising and falling frequencies [1,2,3]. Using test particle simulations, we evaluate the efficiency of scattering, which depends on the inhomogeneity ratio S of whistler mode wave-particle interaction [4]. The value of S is determined by the wave amplitude, frequency sweep rate, and the gradient of the background magnetic field. We first modulate those parameters and observe variations of pitch angles and kinetic energies of electrons with a single wave under various S values so as to obtain basic understanding. We then include many waves into the system to simulate plasmaspheric hiss emissions. As the wave packets propagate away from the magnetic equator, the nonlinear trapping potential at the resonance velocity is deformed, making a channel of gyrophase for untrapped electrons to cross the resonance velocity, and causing modulations in their pitch angles and kinetic energies. We find efficient scattering of pitch angles and kinetic energies because of coherent nonlinear wave-particle interaction, resulting in electron precipitations into the polar atmosphere. We compare the results with the bounce averaged pitch angle diffusion coefficient based on quasi-linear theory, and show that the nonlinear wave model with many coherent packets can cause scattering of resonant electrons much faster than the quasi-linear diffusion process. [1] Summers, D., Omura, Y., Nakamura, S., and C. A. Kletzing (2014), Fine structure of plasmaspheric hiss, J. Geophys. Res., 119, 9134-9149. [2] Omura, Y., Y. Miyashita, M. Yoshikawa, D. Summers, M. Hikishima, Y. Ebihara, and Y. Kubota (2015), Formation process of relativistic electron flux through interaction with chorus emissions in the Earth's inner magnetosphere, J. Geophys. Res. Space Physics, 120, 9545-9562. [3] Nakamura, S., Y
Electron Scattering from MERCURY-198 and Mercury -204.
Laksanaboonsong, Jarungsaeng
This experiment is the first electron scattering study on mercury isotopes. Electron scattering from ^{198}Hg and ^{204 }Hg has been performed at the NIKHEF-K Medium Energy Accelerator. Measured cross sections cover an effective momentum transfer range from 0.4 to 2.9 fm^ {-1}. Elastic cross sections were determined for scattering from both isotopes. Cross section for inelastic excitations in ^{198}Hg below 3 MeV were also determined. Measured cross sections were fit using DWBA phase shift codes to determine coefficients for Fourier-Bessel expansions of ground state and transition charge densities. Differences between the ground state charge densities of the two isotopes reveal the effect of the polarization of the proton core in response to the addition of neutrons. Spin and parity of several excited states of ^{198}Hg were determined. Extracted transition densities of these states show their predominantly collective nature. Charge densities for members of the ground state rotational band were compared with axially symmetric Hartree-Fock and geometrical model predictions.
Deuteron threshold electrodisintegration at high momentum transfer
International Nuclear Information System (INIS)
Schmitt, W.M.; Turchinetz, W.; Williamson, C.F.; Yates, T.C.; Zumbro, J.D.; Lee, K.S.; Baghaei, H.; Churchwell, S.; Hicks, R.S.; Miskimen, R.; Peterson, G.A.; Wang, K.; Bosted, P.E.; Spengos, M.; Frois, B.; Martino, J.; Platchkov, S.; Hotta, A.
1997-01-01
Absolute differential cross sections for the threshold electrodisintegration of the deuteron with good resolution were measured at a laboratory scattering angle of 160 degree for five values of Q 2 ranging from 8.66 to 42.4fm -2 . Comparisons of the data averaged over E np from 0 to 3 MeV and from 0 to 10 MeV are made with nonrelativistic meson exchange calculations. These calculations are sensitive to the nucleon electromagnetic form factors, nucleon-nucleon potential, and relativistic effects. The data are also compared with a hybrid quark-hadron model calculation that describes the deuteron as a six-quark cluster for the short range part of the interaction. Some of these calculations can describe the data reasonably well over certain ranges of Q 2 ; however, none of these calculations can accurately describe the data over the entire measured Q 2 range. copyright 1997 The American Physical Society
Deuteron threshold electrodisintegration at high momentum transfer
International Nuclear Information System (INIS)
Schmitt, W.M.; Turchinetz, W.; Williamson, C.F.
1997-01-01
Absolute differential cross sections for the threshold electrodisintegration of the deuteron with good resolution were measured at a laboratory scattering angle of 160 degree for five values of Q 2 ranging from 8.66 to 42.4 fm -2 . Comparisons of the data averaged over E np from 0--3 MeV and 0--10 MeV are made with nonrelativistic meson-exchange calculations. These calculations are sensitive to the nucleon electromagnetic form factors, nucleon-nucleon potential, and relativistic effects. The data are also compared with a hybrid quark-hadron model calculation that describes the deuteron as a six-quark cluster for the short range part of the interaction. Some of these calculations can describe the data reasonably well over certain ranges of Q 2 ; however, none of these calculations can accurately describe the data over the entire measured Q 2 range
Inversion of the total cross sections for electron-molecule and electron-atom scattering
International Nuclear Information System (INIS)
Lun, D.R.; Amos, K.; Allen, L.J.
1994-01-01
Inverse scattering theory has been applied to construct the interaction potentials from total cross sections as a function of energy for electrons scattered off of atoms and molecules. The underlying potentials are assumed to be real and energy independent and are evaluated using the Eikonal approximation and with real phase shifts determined from the total cross sections. The inversion potentials have been determined using either a high energy limit approximation or by using a fixed energy inversion method at select energies. These procedures have been used to analyse e - - CH 4 , e - - SiH 4 , e - -Kr and e - -Xe scattering data in particular. 14 refs., 1 tabs., 3 figs
Fitting phase shifts to electron-ion elastic scattering measurements
International Nuclear Information System (INIS)
Per, M.C.; Dickinson, A.S.
2000-01-01
We have derived non-Coulomb phase shifts from measured differential cross sections for electron scattering by the ions Na + , Cs + , N 3+ , Ar 8+ and Xe 6+ at energies below the inelastic threshold. Values of the scaled squared deviation between the observed and fitted differential cross sections, χ 2 , for the best-fit phase shifts were typically in the range 3-6 per degree of freedom. Generally good agreement with experiment is obtained, except for wide-angle scattering by Ar 8+ and Xe 6+ . Current measurements do not define phase shifts to better than approx. 0.1 rad even in the most favourable circumstances and uncertainties can be much larger. (author)
Electron scattering times in ZnO based polar heterostructures
Energy Technology Data Exchange (ETDEWEB)
Falson, J., E-mail: j.falson@fkf.mpg.de [Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), The University of Tokyo, Tokyo 113-8656 (Japan); Department of Advanced Materials Science, The University of Tokyo, Kashiwa 277-8561 (Japan); Max Planck Institute for Solid State Research, D-70569 Stuttgart (Germany); Kozuka, Y. [Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), The University of Tokyo, Tokyo 113-8656 (Japan); Smet, J. H. [Max Planck Institute for Solid State Research, D-70569 Stuttgart (Germany); Arima, T. [Department of Advanced Materials Science, The University of Tokyo, Kashiwa 277-8561 (Japan); RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198 (Japan); Tsukazaki, A. [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); PRESTO, Japan Science and Technology Agency (JST), Tokyo 102-0075 (Japan); Kawasaki, M. [Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), The University of Tokyo, Tokyo 113-8656 (Japan); RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198 (Japan)
2015-08-24
The remarkable historic advances experienced in condensed matter physics have been enabled through the continued exploration and proliferation of increasingly richer and cleaner material systems. In this work, we report on the scattering times of charge carriers confined in state-of-the-art MgZnO/ZnO heterostructures displaying electron mobilities in excess of 10{sup 6} cm{sup 2}/V s. Through an examination of low field quantum oscillations, we obtain the effective mass of charge carriers, along with the transport and quantum scattering times. These times compare favorably with high mobility AlGaAs/GaAs heterostructures, suggesting the quality of MgZnO/ZnO heterostructures now rivals that of traditional semiconductors.
Optical potential study of electron scattering by rubidium
Energy Technology Data Exchange (ETDEWEB)
Chin, J. H.; Ratnavelu, K. [University of Malaya, Kuala Lumpur (Malaysia); Zhou, Y. [Harbin Institute of Technology, Harbin (China)
2011-10-15
The coupled-channel optical method (CCOM) has been implemented in a study of electronrubidium scattering. This method includes the continuum effect in the calculation via an ab-initio optical potential. Eight atomic states (5s, 5p, 4d, 6s, 6p, 5d, 7s, 7p) were used together with the continuum optical potential in the 5s-5s, 5s-5p, and 5p-5p coupling. The elastic, inelastic and total cross sections for electron-rubidium scattering at low and intermediate energies, ranging from 10 eV to 100 eV, are reported. The results are compared with available experimental and theoretical data.
Obtaining the crystal potential by inversion from electron scattering intensities
International Nuclear Information System (INIS)
Allen, L.T.; Josefsson, T.W.; Leeb, H.
1998-01-01
A method to obtain the crystal potential from the intensities of the diffracted beams in high energy electron diffraction is proposed. It is based on a series of measurements for specific well determined orientations of the incident beam which determine the moduli of all elements of the scattering matrix. Using unitarity and the specific form of the scattering matrix (including symmetries) an overdetermined set of non-linear equations is obtained from these data. Solution of these equations yields the required phase information and allows the determination of a (projected) crystal potential by inversion which is unique up to an arbitrary shift of the origin. The reconstruction of potentials from intensities is illustrated for two realistic examples, a [111] systematic row case in ZnS and a [110] zone axis orientation in GaAs (both noncentrosymmetric crystals)
Spin effects in medium-energy electron-3He scattering
International Nuclear Information System (INIS)
van den Brand, J.F.J.; Alarcon, R.; Bauer, T.
1998-01-01
New physics can be accessed by scattering polarized electrons from a polarized 3 He internal gas target. It is discussed how the asymmetries for the reactions 3 vector He(vector e,e'), 3 vector He(vector e,e'p), 3 vector He(vector e,e'n), 3 vector He(vector e,e'd), and 3 vector He(vector e,e'pn) may provide precise information on the S' and the D-wave parts of the 3 He ground-state wave function, the neutron form factors, and the role of spin-dependent reaction mechanism effects. The experiment uses up to 900 MeV (polarized) electrons from the AmPS storage ring in Amsterdam, Netherlands, in combination with large acceptance electron and hadron detectors. (orig.)
Intermediate energy electron scattering from sodium and potassium
International Nuclear Information System (INIS)
Buckman, S.J.
1979-06-01
This thesis describes an experimental investigation of the interaction of fast electrons with alkali metal atoms. Several of the theoretical models which have been applied to atomic collision processes including the first Born approximation, the Glauber approximation, the optical model and the distorted wave polarized orbital approximation are discussed. The theory of electron-photon coincidence experiments is outlined and the effects of fine and hyperfine structure on the polarization state of photons emitted from an excited atom are calculated for Sodium. The results of elastic scattering measurements on Sodium and Potassium are presented and used to test several theoretical models in their description of the differential cross section at incident energies between 50 and 200eV. Absolute differential and integrated total cross sections for the Potassium resonance lines and Sodium D-lines are presented. Results of the first electron-polarized photon coincidence experiment on the Sodium D-lines are presented and compared with available theoretical calculations
Multiple scattering of slow muons in an electron gas
International Nuclear Information System (INIS)
Archubi, C.D.; Arista, N.R.
2017-01-01
A comparative study of the angular dispersion of slow muons in an electron gas is performed using 3 dielectric models which represent the case of metals (Lindhard model for a free electron gas) and the cases of semiconductors and insulators (Levine and Louie model and Brandt and Reinheimer model for systems with a band gap) and a non-linear model for both cases at very low velocities. The contribution of collective electronic excitations according to the dielectric model are found to be negligible. The results from the calculation using Lindhard expressions for the angular half width are consistent with the result of a multiple scattering model. In particular, the effects produced by the band gap of the material are analyzed in detail. Finally, as the recoil effect is negligible, there is an almost exact scaling, for a given velocity, between the proton and the muon results. (authors)
Polarized electron-muon neutrino scattering to electron and neutrino in noncommutative space
Directory of Open Access Journals (Sweden)
MM Ettefaghi
2011-06-01
Full Text Available For neutrino scattering from polarized electron, the weak interaction term in the cross section is significantly suppressed by the polarized term. The magnetic moment term does not receive any correction from the electron polarization. Hence, the study of the magnetic moment of neutrinos through scattering from the polarized electron leads to a stronger bound on the neutrino magnetic moment compared with the unpolarized case. On the other hand, neutrinos which are electrically neutral can couple directly with photons in Noncommutative (NC QED. In this paper, we calculate the NC QED corrections on this scattering are calculated. The phase difference between the NC term and the polarized weak interaction term is π/2. Therefore, the NC term does not destroy the above suppression.
International Nuclear Information System (INIS)
Berthot, J.; Bertin, P.Y.; Breton, V.; Deur, A.; Fonvieille, H.; Jaminion, S.; Jutier, C.; Lavessiere, G.; Ravel, O.; Roblin, Y.; Aniol, K.A.; Epstein, M.B.; Margaziotis, D.J.; Howell, C.; Boeglin, W.U.; Kramer, L.H.; Markowitz, P.; Sarty, A.J.; Degrande, N.; Van Hoorebeke, L.; Baker, F.T.; Templon, J.A.; Mougey, J.Y.; Gasparian, A.; Madey, R.; Wilson, R.; De Leo, R.; Leone, A.; Perrino, R.; Cisbani, E.; Frullani, S.; Garibaldi, F.; Iodice, M.; Urciuoli, G.M.; Anderson, B.D.; Katramatou, A.T.; Khayat, M.; Madey, R.; Manley, D.M.; Petratos, G.G.; Prout, D.L.; Suleiman, R.; Watson, J.W.; Zhang, W.; Dale, D.S.; Gasparian, A.; Glamazdin, A.; Gorbenko, V.; Pomatsalyuk, R.; Sorokin, P.; Breuer, H.; Chang, C.; Ewell, L.A.; Kelly, J.J.; Bertozzi, W.; Fissum, K.G.; Gao, H.; Gao, J.; Gilad, S.; Liyanage, N.; Rowntree, D.; Zhao, J.; Zhou, Z.
1999-01-01
The deuteron elastic structure function A(Q 2 ) has been extracted in the range 0.7≤Q 2 ≤6.0 (GeV /c) 2 from cross section measurements of elastic electron-deuteron scattering in coincidence using the Hall A Facility of Jefferson Laboratory. The data are compared to theoretical models, based on the impulse approximation with the inclusion of meson-exchange currents, and to predictions of quark dimensional scaling and perturbative quantum chromodynamics. copyright 1999 The American Physical Society
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.
Large acceptance magnetic spectrometers for polarized deep inelastic electron scattering
International Nuclear Information System (INIS)
Petratos, G.G.; Eisele, R.L.; Gearhart, R.A.; Hughes, E.W.; Young, C.C.
1991-10-01
The design of two magnetic spectrometers for the measurement of the spin-dependent structure function g 1 n of the neutron and a test of the Bjorken sum rule is described. The measurement will consist of scattering 23 GeV polarized electrons off a polarized 3 He target and detecting scattered electrons of 7 to 18 GeV at 4.5 degree and 7 degree. Each spectrometer is based on two large aperture dipole magnets bending in opposite directions. This ''reverse'' deflection design doubles the solid angle as compared to the conventional design of same direction bends used in previous experiments. Proper choice of the deflection angles and the distance between the two dipoles in each spectrometer allows background photons from radiative processes to reach the detectors only after at least two bounces off the spectrometer vacuum walls, resulting in an expected tolerable background. Each spectrometer is equipped with a pair of Cerenkov detectors, a pair of scintillation hodoscopes and a lead-glass shower calorimeter providing electron and pion identification with angular and momentum resolutions sufficient for the experimental measurement. 7 refs., 8 figs., 1 tab
Application of electron back-scatter diffraction to texture research
International Nuclear Information System (INIS)
Randle, V.
1996-01-01
The application of electron back-scatter diffraction (EBSD) to materials research is reviewed. A brief history of the technique is given, followed by a description of present-day operation. The methodology of 'microtexture', i.e. spatially specific orientations, is described and recent examples of its application using EBSD are given, in particular to interstitial-free steel processing, growth of phases in a white iron and grain boundary phenomena in a superplastic alloy. The advantages and disadvantages of EBSD compared to use of X-rays for texture determination are discussed in detail
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.)
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
Electron-positronium scattering in Debye plasma environment
International Nuclear Information System (INIS)
Basu, Arindam; Ghosh, A.S.
2008-01-01
Electron-positronium scattering has been investigated in the Debye plasma environment employing the close-coupling approximation. Three models, viz. 3-state CCA, 6-state CCA and 9-state CCA, have been employed. The 2s 21 S e autodetaching resonant state of the positronium negative ion has been successfully predicted for various plasma environments. The position of the resonance for different Debye lengths are in close agreement with those of Kar and Ho [S. Kar, Y.K. Ho, Phys. Rev. A 71 (2005) 052503
Calculation of electron scattering on the He+ ion
International Nuclear Information System (INIS)
Bray, I.; McCarthy, I.E.; Wigley, J.; Stelbovics, A.T.
1993-11-01
The Convergent Close-Coupling method is applied to the calculation of electron scattering on the ground state of He + . The inclusion of the treatment of the continuum, even below the ionization threshold, significantly reduces the calculated 2S cross section. Generally, it shows good agreement with the measurements of the 2S excitation cross section, though in the vicinity of a few eV near threshold the results are characteristically higher than the experiment. Complete quantitative agreement is obtained with the measurement of the total ionization cross section from threshold to 700 eV. 18 refs., 3 fig
Electron back scattered diffraction study of SmCo magnets
International Nuclear Information System (INIS)
Yonamine, T.; Fukuhara, M.; Machado, R.; Missell, F.P.
2008-01-01
The remanence and energy product of permanent magnets is a strong function of their crystallographic texture. Electron back scattered diffraction (EBSD) is a tool for texture analysis providing information about the atomic layers up to 50 nm below the surface of the material. This paper discusses experimental requirements for performing EBSD measurements on rare-earth permanent magnets and presents results on commercial SmCo magnet material. EBSD measurements proved to be very sensitive to misaligned grains and were sensitive to texture in good agreement with information provided by X-ray diffraction scans. Results for nanostructured Sm(CoFeCuZr) z magnets are also discussed
Vibrationally inelastic electron scattering in a two-channel approximation
Czech Academy of Sciences Publication Activity Database
Čársky, Petr; Čurík, Roman
2008-01-01
Roč. 41, č. 5 (2008), , , 055203-1-6 ISSN 0953-4075 R&D Projects: GA AV ČR IAA100400501; GA AV ČR 1ET400400413; GA AV ČR KJB400400803; GA ČR GA202/08/0631; GA MŠk ME 857 Institutional research plan: CEZ:AV0Z40400503 Keywords : inelastic electron scattering * two-channel approximation Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.089, year: 2008
The new frontiers of electron scattering at intermediate energy
International Nuclear Information System (INIS)
Frois, B.
1984-08-01
Recent advances in experimental techniques have produced a new generation of electron scattering data. This paper explores the frontiers of this field and shows how our prospects for the future may be modified. Nuclear structure has been determined with an unprecedented accuracy defining clearly the limits of the most advanced theoretical descriptions. Large meson exchange currents are measured quantitatively with precision. Recent data on the electrodisintegration of deuterium at threshold and on the magnetic form factor of 3 He and tritium show that the pionic exchange current is well understood. There is no satisfactory theoretical description of shorter range processes
Large momentum transfer electron scattering from few-nucleon systems
International Nuclear Information System (INIS)
Arnold, R.G.
1979-08-01
A review is given of the experimental results from a series of measurements at SLAC of large momentum transfer (Q 2 > 20 fm -2 ) electron scattering at forward angles from nuclei with A less than or equal to 4. Theoretical interpretations of these data in terms of traditional nuclear physics models and in terms of quark constituent models are described. Some physics questions for future experiments are explored, and a preview of possible future measurements of magnetic structure functions of light nuclei at large Q 2 is given
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.)
Noboru, HIROSHIGE; Faculty of Economics, Hannan University
1996-01-01
An energy-dependent partial-wave analysis of πd elastic scattering has been performed in the region T_L=65～294 MeV for currently available experimental data, including the recent vector analyzing power iT_ and composite observables τ_. We have obtained a solution which is in good agreement with the experimental data. The ^3P_1,^3P_2,^3D_3 and ^3D_2 amplitudes abtained show counter-clockwise rotating behaviors.
International Nuclear Information System (INIS)
Allen, L.J.; Spargo, A.E.C.; Leeb, H.
1998-01-01
The retrieval of a unique crystal potential from the scattering matrix S in high energy transmission electron diffraction is discussed. It is shown that, in general, data taken at a single orientation are not sufficient to determine all the elements of S. Additional measurements with tilted incident beam are required for the determination of the whole S-matrix. An algorithm for the extraction of the crystal potential from the S-matrix measured at a single energy and thickness is presented. The limiting case of thin crystals is discussed. Several examples with simulated data are considered
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
Theoretical study of near-threshold electron-molecule scattering
International Nuclear Information System (INIS)
Morrison, M.A.
1989-01-01
We have been engaged in carrying out a foundation study on problems pertaining to near-threshold nuclear excitations in e-H 2 scattering. The primary goals of this study are: to investigate the severity and nature of the anticipated breakdown of the adiabatic-nuclei (AN) approximation, first for rotation only (in the rigid-rotator approximation), and then for vibration; to determine a data base of accurate ab initio cross sections for this important system; to implement and test accurate, computationally-tractable model potentials for exchange and polarization effects; and to begin the exploration of alternative scattering theories for near-threshold collisions. This study has provided a well-defined theoretical context for our future investigations. Second, it has enabled us to identify and quantify several serious problems in the theory of near-threshold electron-molecule scattering that demand attention. And finally, it has led to the development of some of the theoretical and computational apparatus that will form the foundation of future work. In this report, we shall review our progress to date, emphasizing work completed during the current contract year. 17 refs., 5 figs., 1 tab
International Nuclear Information System (INIS)
Saghai, B.
1987-09-01
These measurements are made with pions of positive and negative charge for scattering angles taken between 41 deg and 143 deg. The detector consists in a range spectrometer conceived for this experiment. The total uncertainty in the measured differential cross sections is less than 4%. In the process we extract the charge-asymmetry parameter. A general treatment of radiative corrections for any two-body hadronic collision is developed an applied to the data. In order to test the principle of charge symmetry we make a calculation in the impulse approximation including external and internal Coulomb corrections and a mechanism for charge-symmetry breaking relative to the mass-difference of the neutron and proton and to those of the components of the 33 resonance. This calculation reproduces the cross sections within 20% and exhibits the extreme sensitivity of the asymmetry parameter to the observed structure. Starting from the strong amplitudes calculated from the Faddeev equations and in the framework of the T-matrix, we develop a detailed treatment of the distortions of these amplitudes generated by the Coulomb effects via phase-shift modifications. The comparison of the results with the collection of elastic scattering data, including the polarization observables, between 47 and 360 MeV, shows the importance of the effects treated in the mechanisms brought into play. This calculation reproduces the data rather well and in particular, the structure of the asymmetry parameter at 143 and 256 MeV [fr
Tretiak, Sergei
2014-03-01
The exciton scattering (ES) technique is a multiscale approach developed for efficient calculations of excited-state electronic structure and optical spectra in low-dimensional conjugated macromolecules. Within the ES method, the electronic excitations in the molecular structure are attributed to standing waves representing quantum quasi-particles (excitons), which reside on the graph. The exciton propagation on the linear segments is characterized by the exciton dispersion, whereas the exciton scattering on the branching centers is determined by the energy-dependent scattering matrices. Using these ES energetic parameters, the excitation energies are then found by solving a set of generalized ``particle in a box'' problems on the graph that represents the molecule. All parameters can be extracted from quantum-chemical computations of small molecular fragments and tabulated in the ES library for further applications. Subsequently, spectroscopic modeling for any macrostructure within considered molecular family could be performed with negligible numerical effort. The exciton scattering properties of molecular vertices can be further described by tight-binding or equivalently lattice models. The on-site energies and hopping constants are obtained from the exciton dispersion and scattering matrices. Such tight-binding model approach is particularly useful to describe the exciton-phonon coupling, energetic disorder and incoherent energy transfer in large branched conjugated molecules. Overall the ES applications accurately reproduce the optical spectra compared to the reference quantum chemistry results, and make possible to predict spectra of complex macromolecules, where conventional electronic structure calculations are unfeasible.
Pulsating aurora from electron scattering by chorus waves
Kasahara, S.; Miyoshi, Y.; Yokota, S.; Mitani, T.; Kasahara, Y.; Matsuda, S.; Kumamoto, A.; Matsuoka, A.; Kazama, Y.; Frey, H. U.; Angelopoulos, V.; Kurita, S.; Keika, K.; Seki, K.; Shinohara, I.
2018-02-01
Auroral substorms, dynamic phenomena that occur in the upper atmosphere at night, are caused by global reconfiguration of the magnetosphere, which releases stored solar wind energy. These storms are characterized by auroral brightening from dusk to midnight, followed by violent motions of distinct auroral arcs that suddenly break up, and the subsequent emergence of diffuse, pulsating auroral patches at dawn. Pulsating aurorae, which are quasiperiodic, blinking patches of light tens to hundreds of kilometres across, appear at altitudes of about 100 kilometres in the high-latitude regions of both hemispheres, and multiple patches often cover the entire sky. This auroral pulsation, with periods of several to tens of seconds, is generated by the intermittent precipitation of energetic electrons (several to tens of kiloelectronvolts) arriving from the magnetosphere and colliding with the atoms and molecules of the upper atmosphere. A possible cause of this precipitation is the interaction between magnetospheric electrons and electromagnetic waves called whistler-mode chorus waves. However, no direct observational evidence of this interaction has been obtained so far. Here we report that energetic electrons are scattered by chorus waves, resulting in their precipitation. Our observations were made in March 2017 with a magnetospheric spacecraft equipped with a high-angular-resolution electron sensor and electromagnetic field instruments. The measured quasiperiodic precipitating electron flux was sufficiently intense to generate a pulsating aurora, which was indeed simultaneously observed by a ground auroral imager.
Solar Wind Electron Scattering by Kinetic Instabilities and Whistler Turbulence
Gary, S. P.
2015-12-01
The expansion of the solar wind away from the Sun drives electron velocity distributions away from the thermal Maxwellian form, yielding distributions near 1 AU which typically can be characterized as consisting of three anisotropic components: a more dense, relatively cool core, a relatively tenuous , relatively warm halo and a similarly tenuous, warm strahl. Each of these nonthermal components are potential sources of kinetic plasma instabilities; the enhanced waves from each instability can scatter the electrons, acting to reduce the various anisotropies and making their overall velocity distribution more nearly (but not completely) thermal. In contrast, simulations are demonstrating that the forward decay of whistler turbulence can lead to the development of a T||> T_perp electron anisotropy. This presentation will review linear theories of electron-driven kinetic instabilities (following the presentation by Daniel Verscharen at the 2015 SHINE Workshop), and will further consider the modification of electron velocity distributions as obtained from particle-in-cell simulations of such instabilities as well as from the decay of whistler turbulence.
On selection rules and inelastic electron scattering at intermediate energies
International Nuclear Information System (INIS)
Nuroh, K.
1986-12-01
Correlation effects are included in the Bethe-Born theory for the generalized oscillator strength of inelastic scattering of electrons on atoms. The formulation is such as to allow for the calculation of relative line strengths of multiplets. It is used to analyze line strengths of the 4d → 4f transition in La 3+ and Ce 4+ within LS-coupling. The analysis indicates that only singlet states of the intermediate 4d 9 4f configuration are allowed. Calculated line strengths are compared with a recent core electron energy loss spectra of metallic La and tetravalent CeO 2 and there is an overall qualitative agreement between theory and experiment. (author). 11 refs, 4 figs, 2 tabs
Electron scattering by nuclei and transition charge densities
International Nuclear Information System (INIS)
Gul'karov, I.S.
1988-01-01
Transition charge densities for states of electric type, for nuclei with A≤40--50 as obtained from data on inelastic electron scattering, are studied. The formalism of electroexcitation of nuclei is considered, together with various models (macroscopic and microscopic) used to calculate form factors, transition charge densities, and the moments of these densities: B(Eλ) and R/sub λ/ . The macroscopic models are derived microscopically, and it is shown that the model-independent sum rules lead to the same transition densities as calculations based on various hydrodynamic models. The sum rules with and without allowance for the Skyrme exchange interaction are discussed. The results of the calculations are compared with the experimental form factors of electron scattering by nuclei from 12 C to 48 Ca with excitation in them of normal-parity states with I/sup π/ = 0 + , 1 - , 2 + , 3 - , 4 + , 5 - and T = 0. The model-independent transition charge densities for the weakly collectivized excitations differ strongly from the model-dependent densities. The influence of neutrons on the transition charge densities of the nuclear isotopes 16 /sup ,/ 18 O, 32 /sup ,/ 34 S, and 40 /sup ,/ 48 Ca is considered
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.
Review of two-photon exchange in electron scattering
Energy Technology Data Exchange (ETDEWEB)
J. Arrington, P. G. Blunden, W. Melnitchouk
2011-10-01
We review the role of two-photon exchange (TPE) in electron-hadron scattering, focusing in particular on hadronic frameworks suitable for describing the low and moderate Q^2 region relevant to most experimental studies. We discuss the effects of TPE on the extraction of nucleon form factors and their role in the resolution of the proton electric to magnetic form factor ratio puzzle. The implications of TPE on various other observables, including neutron form factors, electroproduction of resonances and pions, and nuclear form factors, are summarized. Measurements seeking to directly identify TPE effects, such as through the angular dependence of polarization measurements, nonlinear epsilon contributions to the cross sections, and via e+p to e-p cross section ratios, are also outlined. In the weak sector, we describe the role of TPE and gamma-Z interference in parity-violating electron scattering, and assess their impact on the extraction of the strange form factors of the nucleon and the weak charge of the proton.
Observation of second harmonics in laser-electron scattering using low energy electron beam
Energy Technology Data Exchange (ETDEWEB)
Iinuma, Masataka [ADSM, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530 (Japan)]. E-mail: iinuma@hiroshima-u.ac.jp; Matsukado, Koji [Venture Business Laboratory, Hiroshima University, 1-313 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8527 (Japan); Endo, Ichita [ADSM, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530 (Japan); Hashida, Masaki [Institute for chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Hayashi, Kenji [ADSM, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530 (Japan); Kohara, Akitsugu [ADSM, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530 (Japan); Matsumoto, Fumihiko [ADSM, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530 (Japan); Nakanishi, Yoshitaka [ADSM, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530 (Japan); Sakabe, Shuji [Institute for chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Shimizu, Seiji [Institute for chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Tauchi, Toshiaki [High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Yamamoto, Ken [ADSM, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530 (Japan); Takahashi, Tohru [ADSM, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530 (Japan)
2005-10-17
We observed photon generation in the second harmonic region in collisions of 10 keV free electrons and the intense laser beam with the peak intensity of 4.0x10{sup 15} W/cm{sup 2}. Observed photon yield was 3 orders of magnitude higher than expectation from the nonlinear Compton scattering. The observation indicates necessity of further investigation for the interaction between the intense laser field and the low energy electron beam.
International Nuclear Information System (INIS)
Panek, P.; Kaminski, J.Z.; Ehlotzky, F.
2003-01-01
Presently available laser sources can yield powers for which the ponderomotive energy of an electron U p can be equal to or even larger than the rest energy mc 2 of an electron. Therefore it has become of interest to consider fundamental radiation-induced or assisted processes in such powerful laser fields. In the present work we consider laser-induced Compton scattering and laser-assisted electron atom scattering in such fields, assuming that the laser beam has arbitrary elliptic polarization. We investigate in detail the angular and polarisation dependence of the differential cross-sections of the two laser-induced or laser-assisted nonlinear processes as a function of the order N of absorbed or emitted laser photons ω. The present work is a generalization of our previous analysis of Compton scattering and electron-atom scattering in a linearly polarized laser field. (authors)
Low-Energy Electron Scattering by Sugarcane Lignocellulosic Biomass Molecules
Oliveira, Eliane; Sanchez, Sergio; Bettega, Marcio; Lima, Marco; Varella, Marcio
2012-06-01
The use of second generation (SG) bioethanol instead of fossil fuels could be a good strategy to reduce greenhouse gas emissions. However, the efficient production of SG bioethanol has being a challenge to researchers around the world. The main barrier one must overcome is the pretreatment, a very important step in SG bioethanol aimed at breaking down the biomass and facilitates the extraction of sugars from the biomass. Plasma-based treatment, which can generate reactive species, could be an interesting possibility since involves low-cost atmospheric-pressure plasma. In order to offer theoretical support to this technique, the interaction of low-energy electrons from the plasma with biomass is investigated. This study was motived by several works developed by Sanche et al., in which they understood that DNA damage arises from dissociative electron attachment, a mechanism in which electrons are resonantly trapped by DNA subunits. We will present elastic cross sections for low-energy electron scattering by sugarcane biomass molecules, obtained with the Schwinger multichannel method. Our calculations indicate the formation of π* shape resonances in the lignin subunits, while a series of broad and overlapping σ* resonances are found in cellulose and hemicellulose subunits. The presence of π* and σ* resonances could give rise to direct and indirect dissociation pathways in biomass. Then, theoretical resonance energies can be useful to guide the plasma-based pretreatment to break down specific linkages of interest in biomass.
Deuteron interaction with 124Sn nuclei at sub-barrier energies
Directory of Open Access Journals (Sweden)
Yu.N. Pavlenko
2015-04-01
Full Text Available The measurements of cross sections for deuteron elastic scattering and (d,p reaction on 124Sn nuclei have been performed with aim to study the features of sub-barrier deuteron interaction with heavy nuclei. Experimental data were obtained on the electrostatic Tandem accelerator EGP-10K of the Institute for Nuclear Research (Kyiv at the deuteron beam energies Ed = 4.0; 5.0 and 5.5 MeV. Cross sections of deuteron elastic scattering were calculated in approach where the deuteron interaction potential with heavy nuclei at sub-barrier energies has been constructed in the framework of single folding model using the complex dynamic polarization potential. It is shown that the account of finite deuteron size leads to the increasing the nuclear potential in outer region of interaction and significantly improves the description of the experimental data. The calculations of elastic scattering cross sections were performed without any variations of the nuclear potential parameters. The analysis of measured integral cross sections of the 124Sn(d,p reaction and calculated cross sections of deuteron breakup reaction 124Sn(d,pn124Sn shows the dominant contribution of the neutron transfer reaction in the processes of the formation of protons and elastic scattering cross sections.
Energy spectrum of Compton scattering of laser photons on relativistic electrons
International Nuclear Information System (INIS)
Ando, Hiroaki; Yoneda, Yasuharu
1976-01-01
The high energy photons in gamma-ray region are obtainable by the Compton scattering of laser photons on relativistic electrons. But the motion of the electrons in the storage ring is not necessarily uniform. In the study of the uneven effect, the energy distribution of scattered photons is derived from the assumed momentum distribution of incident electrons. It is generally impossible to derive the momentum distribution of incident electrons from the energy spectrum of scattered photons. The additional conditions which make this possible in a special case are considered. A calculational method is examined for deriving the energy spectrum of scattered photons from the assumed momentum distribution of incident electrons. (Mori, K.)
Target fragmentation in deep inelastic scattering of 14.5 GeV electrons from nuclei
International Nuclear Information System (INIS)
Degtyarenko, P.; Gavrilov, V.; Shuvalov, S.
1993-01-01
Results will be presented for inclusive pion, kaon, proton and deuteron electroproduction from light nuclei (mainly 12 C and 16 O) of the residual gas in the beam pipe of the TPC/2γ detector at SLAC. Counter-circulating beams of 14.5 GeV electrons and positrons were used. Comparison will be made with the fragmentation of 2 H, 40 Ar, and Xe target nuclei in several regions of Q 2 and ν. The dependence of the hadron production on the hadron's kinetic energy, emission angle, and x f will be presented. The results will be compared with models of nuclear fragmentation
International Nuclear Information System (INIS)
Nkoma, J.S.
1982-08-01
A quantum-mechanical theory for the inelastic scattering of slow electrons (ISSE) by surface excitations in a thin film is developed. The scattered wave function inside the thin film is obtained by solving the inhomogeneous Schroedinger equation, and it is found to contain terms which show that the back scattered intensity is smaller than the forward scattered intensity. A scattering cross-section for forward scattering is derived and is found to be dependent on transmission factors, wavevectors and fluctuations of the scattering potential. (author)
International Nuclear Information System (INIS)
Saha, H.P.
1993-01-01
The multiconfiguration Hartree-Fock method for continuum wave functions has been used to calculate the scattering length and phase shifts over extremely low energies ranging from 0 to 1 eV very accurately for electron-helium scattering. The scattering length is calculated very accurately with wave functions computed exactly at zero energy, resulting in an upper bound of 1.1784. The electron correlation and polarization of the target by the scattering electron, which are very important in these calculations, have been taken into account in an accurate ab initio manner through the configuration-interaction procedure by optimizing both bound and continuum orbitals simultaneously at each kinetic energy of the scattered electron. Detailed results for scattering length, differential, total, and momentum-transfer cross sections obtained from the phase shifts are presented. The present scattering length is found to be in excellent agreement with the experimental result of Andrick and Bitsch [J. Phys. B 8, 402 (1975)] and the theoretical result of O'Malley, Burke, and Berrington [J. Phys. B 12, 953 (1979)]. There is excellent agreement between the present total cross sections and the corresponding experimental measurements of Buckman and Lohmann [J. Phys. B 19, 2547 (1986)]. The present momentum-transfer cross sections also show remarkable agreement with the experimental results of Crompton, Elford, and Robertson [Aust. J. Phys. 23, 667 (1970)
Hot electron attenuation of direct and scattered carriers across an epitaxial Schottky interface
Parui, S.; Klandermans, P. S.; Venkatesan, S.; Scheu, C.; Banerjee, T.
2013-01-01
Hot electron transport of direct and scattered carriers across an epitaxial NiSi2/n-Si(111) interface, for different NiSi2 thickness, is studied using ballistic electron emission microscopy (BEEM). We find the BEEM transmission for the scattered hot electrons in NiSi2 to be significantly lower than
Signals of strong electronic correlation in ion scattering processes
Bonetto, F.; Gonzalez, C.; Goldberg, E. C.
2016-05-01
Previous measurements of neutral atom fractions for S r+ scattered by gold polycrystalline surfaces show a singular dependence with the target temperature. There is still not a theoretical model that can properly describe the magnitude and the temperature dependence of the neutralization probabilities found. Here, we applied a first-principles quantum-mechanical theoretical formalism to describe the time-dependent scattering process. Three different electronic correlation approaches consistent with the system analyzed are used: (i) the spinless approach, where two charge channels are considered (S r0 and S r+ ) and the spin degeneration is neglected; (ii) the infinite-U approach, with the same charge channels (S r0 and S r+ ) but considering the spin degeneration; and (iii) the finite-U approach, where the first ionization and second ionization energy levels are considered very, but finitely, separated. Neutral fraction magnitudes and temperature dependence are better described by the finite-U approach, indicating that e -correlation plays a significant role in charge-transfer processes. However, none of them is able to explain the nonmonotonous temperature dependence experimentally obtained. Here, we suggest that small changes in the surface work function introduced by the target heating, and possibly not detected by experimental standard methods, could be responsible for that singular behavior. Additionally, we apply the same theoretical model using the infinite-U approximation for the Mg-Au system, obtaining an excellent description of the experimental neutral fractions measured.
Reactive scattering of electronically excited alkali atoms with molecules
International Nuclear Information System (INIS)
Mestdagh, J.M.; Balko, B.A.; Covinsky, M.H.; Weiss, P.S.; Vernon, M.F.; Schmidt, H.; Lee, Y.T.
1987-06-01
Representative families of excited alkali atom reactions have been studied using a crossed beam apparatus. For those alkali-molecule systems in which reactions are also known for ground state alkali and involve an early electron transfer step, no large differences are observed in the reactivity as Na is excited. More interesting are the reactions with hydrogen halides (HCl): it was found that adding electronic energy into Na changes the reaction mechanism. Early electron transfer is responsible of Na(5S, 4D) reactions, but not of Na(3P) reactions. Moreover, the NaCl product scattering is dominated by the HCl - repulsion in Na(5S, 4D) reactions, and by the NaCl-H repulsion in the case of Na(3P). The reaction of Na with O 2 is of particular interest since it was found to be state specific. Only Na(4D) reacts, and the reaction requires restrictive constraints on the impact parameter and the reactants' relative orientation. The reaction with NO 2 is even more complex since Na(4D) leads to the formation of NaO by two different pathways. It must be mentioned however, that the identification of NaO as product in these reactions has yet to be confirmed
Past, present and future polarization experiments with deuterons
International Nuclear Information System (INIS)
Punjabi, V.; Perdrisat, C.F.
1996-01-01
Recent experimental data for the inclusive breakup reaction A(d, p)X, with emphasis on 1 H(d, p)X, and the backward elastic scattering reaction dp → pd are discussed. There is now a fairly complete data base for these reactions, with measurements of the differential cross section, the tensor analyzing power T 20 and the deuteron to proton polarization transfer k 0 . The relevance of these reactions to the study of the short range properties of the deuteron is estimated [ru
Low energy pion--nucleon and pion--deuteron interactions
International Nuclear Information System (INIS)
Burman, R.L.
1975-01-01
This survey concentrates upon current experiments in the fields of pion-nucleon and pion-deuteron interactions, for low-energy incident pions--below 300 MeV. The discussion is restricted to very recent work. The topics to be covered are: π +- p → π +- p, Elastic Scattering; π +- p → π +- pγ, Bremsstrahlung; π + d → pp, Absorption; π d → π + d, Elastic Scattering; and π + d → π + pn, Breakup. (14 figures) (U.S.)
Giant magnetic quadrupole resonance studied with 180 deg. electron scattering
Neumann-Cosel, P V
1999-01-01
The nuclei sup 4 sup 8 Ca and sup 9 sup 0 Zr were investigated in 180 deg. high-resolution inelastic electron scattering for momentum transfers q approx =0.35-0.8 fm sup - sup 1. Complete M2 strength distributions could be extracted in both nuclei up to excitation energies of about 15 MeV utilizing a fluctuation analysis technique. Second-RPA calculations successfully describe the experimentally observed strong fragmentation of the M2 mode. The quenching of the spin part is found to be comparable to the M1 case, contrary to previous claims suggesting a stronger reduction. A quantitative reproduction of the data requires the presence of appreciable orbital strength which can be interpreted as a torsional elastic vibration (the so-called twist mode).
Terrestrial effects on dark matter-electron scattering experiments
DEFF Research Database (Denmark)
Emken, Timon; Kouvaris, Chris; Shoemaker, Ian M.
2017-01-01
A well-studied possibility is that dark matter may reside in a sector secluded from the Standard Model, except for the so-called photon portal: kinetic mixing between the ordinary and dark photons. Such interactions can be probed in dark matter direct detection experiments, and new experimental...... techniques involving detection of dark matter-electron scattering offer new sensitivity to sub-GeV dark matter. Typically however it is implicitly assumed that the dark matter is not altered as it traverses the Earth to arrive at the detector. In this paper we study in detail the effects of terrestrial...... stopping on dark photon models of dark matter, and find that they significantly reduce the sensitivity of XENON10 and DAMIC. In particular we find that XENON10 only excludes masses in the range (5-3000) MeV while DAMIC only probes (20-50) MeV. Their corresponding cross section sensitivity is reduced...
Parity violation in inelastic scattering of polarized electrons
International Nuclear Information System (INIS)
Prescott, C.Y.
1978-10-01
Parity nonconservation was observed in the inelastic scattering of longitudinally polarized electrons from an unpolarized deuterium target at 19.4 and 22.2 GeV. An asymmetry A = (sigma/sub R/ - sigma/sub L)/(sigma/sub R/ + sigma/sub L/) = (-9.5 +- 1.6) x 10 -5 Q 2 , Q 2 in (GeV/c) 2 was found for values of Q 2 near 1.4. The statistical and systematic errors are each about 9 percent of the measured asymmetry. This result is consistent with predictions from the standard Weinberg--Salam SU(2) x U(1) model. Using the simple quark-parton model of the nucleon, the value sin 2 theta/sub W/ = 0.20 +- 0.03 is obtained. 21 references
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
Observation of fluxes of electrons scattered by the atmosphere in the second Araks experiment
International Nuclear Information System (INIS)
Lyachov, S.B.; Managadze, G.G.
1980-01-01
This paper describes the results of the USHBA spectrometer measurements of the fluxes of atmospheric scattered electrons in the second Araks experiment. The experimental data are presented for heights from 100 to 140 km. The spectral distributions of the scattered electron fluxes are given and the altitude variation of their intensity is compared with the atmosphere models. The conclusion is made about the possible effect of rocket gassing on the electron scattering processes for definite angles of injection
Proton-deuteron phase-shift analysis above the deuteron breakup threshold
Energy Technology Data Exchange (ETDEWEB)
Tornow, W. [Duke Univ., Durham, NC (United States). Dept. of Physics]|[Triangle Universities Nuclear Laboratory, Box 90308, Durham, NC (United States); Witala, H. [Institute of Physics, Jagellonian University, Reymonta 4, 30059 Cracow (Poland)
1998-03-02
We have performed single-energy phase-shift analyses of proton-deuteron elastic scattering data in the proton energy range from 3.5 to 10 MeV. The resulting values for the {sup 2}S{sub 1/2} and {sup 4}P{sub 1/2}, {sup 4}P{sub 3/2}, and {sup 4}P{sub 5/2} phase shifts are important benchmark values for three-nucleon calculations based on nucleon-nucleon potential models (with and without three-nucleon forces) aimed at describing the triton binding energy and at resolving the nucleon-deuteron A{sub y}({theta}) and iT{sub 11}({theta}) puzzles, respectively. (orig.) 7 refs.
Hard breakup of the deuteron into two Δ isobars
International Nuclear Information System (INIS)
Granados, Carlos G.; Sargsian, Misak M.
2011-01-01
We study high-energy photodisintegration of the deuteron into two Δ isobars at large center of mass angles within the QCD hard rescattering model (HRM). According to the HRM, the process develops in three main steps: the photon knocks a quark from one of the nucleons in the deuteron; the struck quark rescatters off a quark from the other nucleon sharing the high energy of the photon; then the energetic quarks recombine into two outgoing baryons which have large transverse momenta. Within the HRM, the cross section is expressed through the amplitude of pn→ΔΔ scattering which we evaluated based on the quark-interchange model of hard hadronic scattering. Calculations show that the angular distribution and the strength of the photodisintegration is mainly determined by the properties of the pn→ΔΔ scattering. We predict that the cross section of the deuteron breakup to Δ ++ Δ - is 4-5 times larger than that of the breakup to the Δ + Δ 0 channel. Also, the angular distributions for these two channels are markedly different. These can be compared with the predictions based on the assumption that two hard Δ isobars are the result of the disintegration of the preexisting ΔΔ components of the deuteron wave function. In this case, one expects the angular distributions and cross sections of the breakup in both Δ ++ Δ - and Δ + Δ 0 channels to be similar.
Exclusive $\\rho^0$ muoproduction on transversely polarised protons and deuterons
Adolph, C.; Alexakhin, V.Yu.; Alexandrov, Yu.; Alexeev, G.D.; Amoroso, A.; Antonov, A.A.; Austregesilo, A.; Badelek, B.; Balestra, F.; Barth, J.; Baum, G.; Bedfer, Y.; Bernhard, J.; Bertini, R.; Bettinelli, M.; Bicker, K.; Bieling, J.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, F.; Braun, C.; Bravar, A.; Bressan, A.; Buchele, M.; Burtin, E.; Capozza, L.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Crespo, M.L.; Dalla Torre, S.; Das, S.; Dasgupta, S.S.; Dasgupta, S.; Denisov, O.Yu.; Dhara, L.; Donskov, S.V.; Doshita, N.; Duic, V.; Dunnweber, W.; Dziewiecki, M.; Efremov, A.; Elia, C.; Eversheim, P.D.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Finger, M., Jr.; Fischer, H.; Franco, C.; du Fresne von Hohenesche, N.; Friedrich, J.M.; Frolov, V.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.P.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Grabmuller, S.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Guthorl, T.; Haas, F.; von Harrach, D.; Heinsius, F.H.; Herrmann, F.; Hess, C.; Hinterberger, F.; Horikawa, N.; Hoppner, Ch.; d'Hose, N.; Ishimoto, S.; Ivanov, O.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jary, V.; Jasinski, P.; Jegou, G.; Joosten, R.; Kabuss, E.; Kang, D.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu.A.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koblitz, S.; Koivuniemi, J.H.; Kolosov, V.N.; Kondo, K.; Konigsmann, K.; Konorov, I.; Konstantinov, V.F.; Korzenev, A.; Kotzinian, A.M.; Kouznetsov, O.; Kramer, M.; Kroumchtein, Z.V.; Kunne, F.; Kurek, K.; Lauser, L.; Lednev, A.A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Liska, T.; Maggiora, A.; Magnon, A.; Makke, N.; Mallot, G.K.; Mann, A.; Marchand, C.; Martin, A.; Marzec, J.; Matsuda, T.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Yu.V.; Moinester, M.A.; Morreale, A.; Mutter, A.; Nagaytsev, A.; Nagel, T.; Negrini, T.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.I.; Nowak, W.D.; Nunes, A.S.; Olshevsky, A.G.; Ostrick, M.; Padee, A.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Perevalova, E.; Pesaro, G.; Peshekhonov, D.V.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.A.; Pretz, J.; Quaresma, M.; Quintans, C.; Rajotte, J.F.; Ramos, S.; Rapatsky, V.; Reicherz, G.; Richter, A.; Rocco, E.; Rondio, E.; Rossiyskaya, N.S.; Ryabchikov, D.I.; Samoylenko, V.D.; Sandacz, A.; Sapozhnikov, M.G.; Sarkar, S.; Savin, I.A.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schluter, T.; Schmidt, K.; Schmitt, L.; Schonning, K.; Schopferer, S.; Schott, M.; Schroder, W.; Shevchenko, O.Yu.; Silva, L.; Sinha, L.; Sissakian, A.N.; Slunecka, M.; Smirnov, G.I.; Sosio, S.; Sozzi, F.; Srnka, A.; Steiger, L.; Stolarski, M.; Sulc, M.; Sulej, R.; Suzuki, H.; Sznajder, P.; Takekawa, S.; Ter Wolbeek, J.; Tessaro, S.; Tessarotto, F.; Tkatchev, L.G.; Uhl, S.; Uman, I.; Vandenbroucke, M.; Virius, M.; Vlassov, N.V.; Wang, L.; Wilfert, M.; Windmolders, R.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zhuravlev, N.; Zvyagin, A.
2012-01-01
The transverse target spin azimuthal asymmetry A_UT in hard exclusive production of rho^0 mesons was measured at COMPASS by scattering 160 GeV/c muons off transversely polarised protons and deuterons. The measured asymmetry is sensitive to the nucleon helicity-flip generalised parton distributions E^q, which are related to the orbital angular momentum of quarks in the nucleon. The Q^2, x_B and p_t^2 dependence of A_UT is presented in a wide kinematic range. Results for deuterons are obtained for the first time. The measured asymmetry is small in the whole kinematic range for both protons and deuterons, which is consistent with the theoretical interpretation that contributions from GPDs E^u and E^d approximately cancel.
Angular distribution of scattered electron and medium energy electron spectroscopy for metals
International Nuclear Information System (INIS)
Oguri, Takeo; Ishioka, Hisamichi; Fukuda, Hisashi; Irako, Mitsuhiro
1986-01-01
The angular distribution (AD) of scattered electrons produced by medium energy incident electrons (E P = 50 ∼ 300 eV) from polycrystalline Ti, Fe, Ni, Cu and Au were obtained by the angle-resolved medium energy electron spectrometer. The AD of the energy loss peaks are similar figures to AD of the elastically reflected electron peaks. Therefore, the exchanged electrons produced by the knock-on collision between the incident electrons and those of metals without momentum transfer are observed as the energy loss spectra (ELS). This interpretation differs from the inconsequent interpretation by the dielectric theory or the interband transition. The information depth and penetration length are obtained from AD of the Auger electron peaks. The contribution of the surface to spectra is 3 % at the maximum for E P = 50 eV. The true secondary peaks representing the secondary electron emission spectroscopy (SES) are caused by the emissions of the energetic electrons (kT e ≥ 4 eV), and SES is the inversion of ELS. The established fundamental view is that the medium energy electron spectra represent the total bulk density of states. (author)
Electron-He+ P-wave elastic scattering and photoabsorption in two-electron systems
International Nuclear Information System (INIS)
Bhatia, A. K.
2006-01-01
In a previous paper [A. K. Bhatia, Phys. Rev. A 69, 032714 (2004)], electron-hydrogen P-wave scattering phase shifts were calculated using the optical potential approach based on the Feshbach projection operator formalism. This method is now extended to the singlet and triplet electron-He + P-wave scattering in the elastic region. Phase shifts are calculated using Hylleraas-type correlation functions with up to 220 terms. Results are rigorous lower bounds to the exact phase shifts, and they are compared to phase shifts obtained from the method of polarized orbitals and close-coupling calculations. The continuum functions calculated here are used to calculate photoabsorption cross sections. Photoionization cross sections of He and photodetachment cross sections of H - are calculated in the elastic region--i.e., leaving He + and H in their respective ground states--and compared with previous calculations. Radiative attachment rates are also calculated
Spin entanglement in elastic electron scattering from quasi-one electron atoms
Fonseca Dos Santos, Samantha; Bartschat, Klaus
2017-04-01
We have extended our work on e-Li collisions to investigate low-energy elastic electron collisions with atomic hydrogen and other alkali targets (Na,K,Rb). These systems have been suggested for the possibility of continuously varying the degree of entanglement between the elastically scattered projectile and the valence electron. In order to estimate how well such a scheme may work in practice, we carried out overview calculations for energies between 0 and 10 eV and the full range of scattering angles 0° -180° . In addition to the relative exchange asymmetry parameter that characterizes the entanglement, we present the differential cross section in order to estimate whether the count rates in the most interesting energy-angle regimes are sufficient to make such experiments feasible in practice. Work supported by the NSF under PHY-1403245.
Kaya, Ismet I.; Eberl, Karl
2007-05-01
A three-terminal device formed by two electrostatic barriers crossing an asymmetrically patterned two-dimensional electron gas displays an unusual potential depression at the middle contact, yielding absolute negative resistance. The device displays momentum and current transfer ratios that far exceed unity. The observed reversal of the current or potential in the middle terminal can be interpreted as the analog of Bernoulli’s effect in a Fermi liquid. The results are explained by directional scattering of electrons in two dimensions.
Energy distribution of 0. 279 MeV gamma rays Compton scattered from bound electrons
Energy Technology Data Exchange (ETDEWEB)
Singh, B; Singh, P; Singh, G; Ghumman, B S
1984-11-01
Energy and intensity distribution of 0.279 MeV gamma rays Compton scattered from K-shell electrons of tantalum is measured at scattering angle of 70deg. The experimental results are compared with the available theoretical data. Spectral distribution is also obtained as a function of scatterer thickness to account for the contribution of false events. 13 refs.
Pressure shifts and electron scattering in atomic and molecular gases
International Nuclear Information System (INIS)
Rupnik, K.; McGlynn, S.P.; Asaf, U.
1994-01-01
In this work, the authors focus on one aspect of Rydberg electron scattering, namely number density effects in molecular gases. The recent study of Rydberg states of CH 3 I and C 6 H 6 perturbed by H 2 is the first attempt to investigate number density effects of a molecular perturber on Rydberg electrons. Highly excited Rydberg states, because of their ''large orbital'' nature, are very sensitive to the surrounding medium. Photoabsorption or photoionization spectra of CH 3 I have also been measured as a function of perturber pressure in 11 different binary gas mixtures consisting of CH 3 I and each one of eleven different gaseous perturbers. Five of the perturbers were rare gases (He, Ne, Ar, Kr, Xe) and six were non-dipolar molecules (H 2 , CH 4 , N 2 , C 2 H 6 , C 3 H 8 ). The goal of this work is to underline similarities and differences between atomic and molecular perturbers. The authors first list some results of the molecular study
International Nuclear Information System (INIS)
Melkonyan, S.V.
2012-01-01
The problem of electron mobility variance is discussed. It is established that in equilibrium semiconductors the mobility variance is infinite. It is revealed that the cause of the mobility variance infinity is the threshold of phonon emission. The electron-phonon interaction theory in the presence of an electric field is developed. A new mechanism of electron scattering, called electron-phonon field-induced tunnel (FIT) scattering, is observed. The effect of the electron-phonon FIT scattering is explained in terms of penetration of the electron wave function into the semiconductor band gap in the presence of an electric field. New and more general expressions for the electron-non-polar optical phonon scattering probability and relaxation time are obtained. The results show that FIT transitions have principle meaning for the mobility fluctuation theory: mobility variance becomes finite.
International Nuclear Information System (INIS)
Inokuti, M.; Manson, S.T.
1982-01-01
We begin with a resume of the Bethe theory, which provides a general framework for discussing the inelastic scattering of fast electrons and leads to powerful criteria for judging the reliability of cross-section data. The central notion of the theory is the generalized oscillator strength as a function of both the energy transfer and the momentum transfer, and is the only non-trivial factor in the inelastic-scattering cross section. Although the Bethe theory was initially conceived for free atoms, its basic ideas apply to solids, with suitable generalizations; in this respect, the notion of the dielectric response function is the most fundamental. Topics selected for discussion include the generalized oscillator strengths for the K-shell and L-shell ionization for all atoms with Z less than or equal to 30, evaluated by use of the Hartree-Slater potential. As a function of the energy transfer, the generalized oscillator strength most often shows a non-monotonic structure near the K-shell and L-shell thresholds, which has been interpreted as manifestations of electron-wave propagation through atomic fields. For molecules and solids, there are additional structures due to the scattering of ejected electrons by the fields of other atoms
Scattering of electrons by alkali-halide molecules: LiBr and CsCl
International Nuclear Information System (INIS)
Vukovic, L.; Zuo, M.; Shen, G.F.; Stumpf, B.; Bederson, B.
1989-01-01
We have investigated small-angle electron scattering by highly polar molecules. Recoil experiments are performed at 5 and 20 eV for electrons scattered by LiBr and CsCl, within the shadow of the unscattered molecular beam. Low-angular-range scattering described by the Born approximation for rotating dipoles, combined with different theories for intermediate- and high-angle scattering, are compared with our results. Evaluated total scattering cross sections as well as momentum-transfer and viscosity cross sections are given. A general two-dimensional analysis of the recoil experiment is presented
Jones, D. B.; da Costa, R. F.; Varella, M. T. do N.; Bettega, M. H. F.; Lima, M. A. P.; Blanco, F.; García, G.; Brunger, M. J.
2016-04-01
We report absolute experimental integral cross sections (ICSs) for electron impact excitation of bands of electronic-states in furfural, for incident electron energies in the range 20-250 eV. Wherever possible, those results are compared to corresponding excitation cross sections in the structurally similar species furan, as previously reported by da Costa et al. [Phys. Rev. A 85, 062706 (2012)] and Regeta and Allan [Phys. Rev. A 91, 012707 (2015)]. Generally, very good agreement is found. In addition, ICSs calculated with our independent atom model (IAM) with screening corrected additivity rule (SCAR) formalism, extended to account for interference (I) terms that arise due to the multi-centre nature of the scattering problem, are also reported. The sum of those ICSs gives the IAM-SCAR+I total cross section for electron-furfural scattering. Where possible, those calculated IAM-SCAR+I ICS results are compared against corresponding results from the present measurements with an acceptable level of accord being obtained. Similarly, but only for the band I and band II excited electronic states, we also present results from our Schwinger multichannel method with pseudopotentials calculations. Those results are found to be in good qualitative accord with the present experimental ICSs. Finally, with a view to assembling a complete cross section data base for furfural, some binary-encounter-Bethe-level total ionization cross sections for this collision system are presented.
Pascal, Elena; Singh, Saransh; Callahan, Patrick G; Hourahine, Ben; Trager-Cowan, Carol; Graef, Marc De
2018-04-01
Transmission Kikuchi diffraction (TKD) has been gaining momentum as a high resolution alternative to electron back-scattered diffraction (EBSD), adding to the existing electron diffraction modalities in the scanning electron microscope (SEM). The image simulation of any of these measurement techniques requires an energy dependent diffraction model for which, in turn, knowledge of electron energies and diffraction distances distributions is required. We identify the sample-detector geometry and the effect of inelastic events on the diffracting electron beam as the important factors to be considered when predicting these distributions. However, tractable models taking into account inelastic scattering explicitly are lacking. In this study, we expand the Monte Carlo (MC) energy-weighting dynamical simulations models used for EBSD [1] and ECP [2] to the TKD case. We show that the foil thickness in TKD can be used as a means of energy filtering and compare band sharpness in the different modalities. The current model is shown to correctly predict TKD patterns and, through the dictionary indexing approach, to produce higher quality indexed TKD maps than conventional Hough transform approach, especially close to grain boundaries. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.
Diffraction and absorption of inelastically scattered electrons for K-shell ionization
International Nuclear Information System (INIS)
Josefsson, T.W.; Allen, L.J.
1995-01-01
An expression for the nonlocal inelastic scattering cross section for fast electrons in a crystalline environment, which explicitly includes diffraction as well as absorption for the inelastically scattered electrons, is used to carry out realistic calculations of K-shell electron energy loss spectroscopy (EELS) and energy dispersive x-ray (EDX) analysis cross sections. The calculations demonstrate quantitatively why, in EDX spectroscopy, integration over the dynamical states of the inelastically scattered electron averages in such a way that an effective plane wave representation of the scattered electrons is a good approximation. This is only the case for large enough acceptance angles of the detector in an EELS experiment. For EELS with smaller detector apertures, explicit integration over the dynamical final states is necessary and inclusion of absorption for the scattered electrons is important, particularly for thicker crystals. 50 refs., 7 figs
Measurement of the reaction 2H(e,e') at 180 degrees close to the deuteron breakup threshold.
Ryezayeva, N; Arenhövel, H; Burda, O; Byelikov, A; Chernykh, M; Enders, J; Griesshammer, H W; Kalmykov, Y; von Neumann-Cosel, P; Ozel, B; Poltoratska, I; Pysmenetska, I; Rangacharyulu, C; Rathi, S; Richter, A; Schrieder, G; Shevchenko, A; Yevetska, O
2008-05-02
Inclusive inelastic electron scattering off the deuteron under 180 degrees has been studied at the S-DALINAC close to the breakup threshold at momentum transfers q=0.27 fm;{-1} and 0.74 fm;{-1} with good energy resolution sufficient to map in detail the spin flip M1 response, which governs the starting reaction pn-->dgamma of big-bang nucleosynthesis over most of the relevant temperature region. Results from potential model calculations and (for q=0.27 fm;{-1}) from pionless nuclear effective field theory are in excellent agreement with the data.
Density-dependent electron scattering in photoexcited GaAs in strongly diffusive regime
DEFF Research Database (Denmark)
Mics, Zoltán; D’Angio, Andrea; Jensen, Søren A.
2013-01-01
In a series of systematic optical pump–terahertz probe experiments, we study the density-dependent electron scattering rate in photoexcited GaAs in the regime of strong carrier diffusion. The terahertz frequency-resolved transient sheet conductivity spectra are perfectly described by the Drude...... model, directly yielding the electron scattering rates. A diffusion model is applied to determine the spatial extent of the photoexcited electron-hole gas at each moment after photoexcitation, yielding the time-dependent electron density, and hence the density-dependent electron scattering time. We find...
X-ray, neutron, and electron scattering. Report of a materials sciences workshop
International Nuclear Information System (INIS)
1977-08-01
The ERDA Workshop on X-ray, Neutron, and Electron Scattering to assess needs and establish priorities for energy-related basic research on materials. The general goals of the Workshop were: (1) to review various energy technologies where x-ray, neutron, and electron scattering techniques might make significant contributions, (2) to identify present and future materials problems in the energy technologies and translate these problems into requirements for basic research by x-ray, neutron, and electron scattering techniques, (3) to recommend research areas utilizing these three scattering techniques that should be supported by the DPR Materials Sciences Program, and (4) to assign priorities to these research areas
Electron scattering from atoms in the presence of a laser field. III
International Nuclear Information System (INIS)
Mittleman, M.H.
1977-01-01
The development of the theory of the effect of a laser on electron-atom scattering is continued by the derivation of explicit relations between the observed electron-atom scattering cross sections in the presence of a laser and exact electron-atom scattering cross sections with no laser present. No approximation concerning the scattering interaction is made. The only approximations concerning the laser are that (1) the laser-atom interaction energy is small compared to atomic energies, (2) the Rabi frequency times the collision time is small, and (3) the laser intensity in appropriate units is small
Compton scattering of 145 keV gamma rays by K-shell electrons of silver
Energy Technology Data Exchange (ETDEWEB)
Acharya, V B; Singh, B; Ghumman, B S [Punjabi Univ., Patiala (India). Dept. of Physics
1981-01-01
Differential cross-sections for the incoherent scattering of 145 keV photons from K-shell electrons of silver are measured at scattering angles ranging from 30/sup 0/ to 150/sup 0/ to investigate the effect of electron binding on the scattering process in the low energy region. Measurements are made employing two NaI (Tl) scintillation spectrometers and a slow-fast coincidence circuit of resolving time 30 ns. The experimental results are compared with the available theoretical data. The total K-shell scattering cross-section is also estimated and is about 45% of the free electron cross-section.
Possible role of double scattering in electron-atom scattering in a laser field
International Nuclear Information System (INIS)
Rabadan, I.; Mendez, L.; Dickinson, A.S.
1996-01-01
By considering observations of double-scattering effects in the excitation of the 2 1 P level of He, gas density values estimated for the laser-assisted elastic scattering experiments of Wallbank and Holmes (1993, 1994a,b) for which the Kroll-Watson approximation appears to fail. Using comparable densities for He and lower densities for Ar, and assuming the Kroll-Watson approximation for single-scattering events, differential cross sections are calculated including double scattering for laser-assisted scattering for a range of energies and scattering angles. Comparison with the observed values shows that double-scattering effects can give a semi-quantitative explanation of the apparent breakdown of the Kroll-Watson approximation in both He and Ar. (author)
Borowik, Piotr; Thobel, Jean-Luc; Adamowicz, Leszek
2017-12-01
The Monte Carlo simulation method is applied to study the relaxation of excited electrons in monolayer graphene. The presence of spin polarized background electrons population, with density corresponding to highly degenerate conditions is assumed. Formulas of electron-electron scattering rates, which properly account for electrons presence in two energetically degenerate, inequivalent valleys in this material are presented. The electron relaxation process can be divided into two phases: thermalization and cooling, which can be clearly distinguished when examining the standard deviation of electron energy distribution. The influence of the exchange effect in interactions between electrons with parallel spins is shown to be important only in transient conditions, especially during the thermalization phase.
A new theoretical model for scattering of electrons by molecules. 1
International Nuclear Information System (INIS)
Peixoto, E.M.A.; Mu-tao, L.; Nogueira, J.C.
1975-01-01
A new theoretical model for electron-molecule scattering is suggested. The e-H 2 scattering is studied and the superiority of the new model over the commonly used Independent Atom Model (IAM) is demonstrated. Comparing theoretical and experimental data for 40keV electrons scattered by H 2 utilizing the new model, its validity is proved, while Partial Wave and First Born calculations, employing the Independent Atom Model, strongly deviated from the experiment [pt
Chiral recognition in electron scattering by S- and R-2-butanol
DEFF Research Database (Denmark)
Jones, Nykola C.; Hoffmann, Søren Vrønning; Field, David
2015-01-01
Experiments are described involving the low energy scattering of electrons from the two optical enantiomers S- and R- 2-butanol. Using a synchrotron radiation photoionization source on the ASTRID storage ring, scattering spectra are reported between a few meV and 140 meV at an electron energy...
An Efficient Method for Electron-Atom Scattering Using Ab-initio Calculations
Energy Technology Data Exchange (ETDEWEB)
Xu, Yuan; Yang, Yonggang; Xiao, Liantuan; Jia, Suotang [Shanxi University, Taiyuan (China)
2017-02-15
We present an efficient method based on ab-initio calculations to investigate electron-atom scatterings. Those calculations profit from methods implemented in standard quantum chemistry programs. The new approach is applied to electron-helium scattering. The results are compared with experimental and other theoretical references to demonstrate the efficiency of our method.
Energy Technology Data Exchange (ETDEWEB)
Jones, D. B. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Costa, R. F. da [Instituto de Física “Gleb Wataghin,” Universidade Estadual de Campinas, Campinas, 13083-859 São Paulo (Brazil); Departamento de Física, Universidade Federal do Espírito Santo, 29075-910, Vitória, Espírito Santo (Brazil); Varella, M. T. do N. [Instituto de Física, Universidade de São Paulo, CP 66318, 05315-970 São Paulo (Brazil); Bettega, M. H. F. [Departamento de Física, Universidade Federal do Paraná, CP 19044, 81531-990 Curitiba, Paraná (Brazil); Lima, M. A. P. [Instituto de Física “Gleb Wataghin,” Universidade Estadual de Campinas, Campinas, 13083-859 São Paulo (Brazil); Blanco, F. [Departamento de Física Atómica, Molecular y Nuclear, Universidad Complutense de Madrid, Madrid E-28040 (Spain); García, G. [Instituto de Física Fundamental, CSIC, Serrano 113-bis, 28006 Madrid (Spain); Brunger, M. J., E-mail: Michael.Brunger@flinders.edu.au [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia)
2016-04-14
We report absolute experimental integral cross sections (ICSs) for electron impact excitation of bands of electronic-states in furfural, for incident electron energies in the range 20–250 eV. Wherever possible, those results are compared to corresponding excitation cross sections in the structurally similar species furan, as previously reported by da Costa et al. [Phys. Rev. A 85, 062706 (2012)] and Regeta and Allan [Phys. Rev. A 91, 012707 (2015)]. Generally, very good agreement is found. In addition, ICSs calculated with our independent atom model (IAM) with screening corrected additivity rule (SCAR) formalism, extended to account for interference (I) terms that arise due to the multi-centre nature of the scattering problem, are also reported. The sum of those ICSs gives the IAM-SCAR+I total cross section for electron–furfural scattering. Where possible, those calculated IAM-SCAR+I ICS results are compared against corresponding results from the present measurements with an acceptable level of accord being obtained. Similarly, but only for the band I and band II excited electronic states, we also present results from our Schwinger multichannel method with pseudopotentials calculations. Those results are found to be in good qualitative accord with the present experimental ICSs. Finally, with a view to assembling a complete cross section data base for furfural, some binary-encounter-Bethe-level total ionization cross sections for this collision system are presented.
International Nuclear Information System (INIS)
Jones, D. B.; Costa, R. F. da; Varella, M. T. do N.; Bettega, M. H. F.; Lima, M. A. P.; Blanco, F.; García, G.; Brunger, M. J.
2016-01-01
We report absolute experimental integral cross sections (ICSs) for electron impact excitation of bands of electronic-states in furfural, for incident electron energies in the range 20–250 eV. Wherever possible, those results are compared to corresponding excitation cross sections in the structurally similar species furan, as previously reported by da Costa et al. [Phys. Rev. A 85, 062706 (2012)] and Regeta and Allan [Phys. Rev. A 91, 012707 (2015)]. Generally, very good agreement is found. In addition, ICSs calculated with our independent atom model (IAM) with screening corrected additivity rule (SCAR) formalism, extended to account for interference (I) terms that arise due to the multi-centre nature of the scattering problem, are also reported. The sum of those ICSs gives the IAM-SCAR+I total cross section for electron–furfural scattering. Where possible, those calculated IAM-SCAR+I ICS results are compared against corresponding results from the present measurements with an acceptable level of accord being obtained. Similarly, but only for the band I and band II excited electronic states, we also present results from our Schwinger multichannel method with pseudopotentials calculations. Those results are found to be in good qualitative accord with the present experimental ICSs. Finally, with a view to assembling a complete cross section data base for furfural, some binary-encounter-Bethe-level total ionization cross sections for this collision system are presented.
Electron scattering from high-momentum neutrons in deuterium
International Nuclear Information System (INIS)
Klimenko, A.V.; Kuhn, S.E.; Bueltmann, S.; Careccia, S.L.; Dharmawardane, K.V.; Dodge, G.E.; Guler, N.; Hyde-Wright, C.E.; Klein, A.; Tkachenko, S.; Weinstein, L.B.; Zhang, J.; Butuceanu, C.; Griffioen, K.A.; Baillie, N.; Fersch, R.G.; Funsten, H.; Egiyan, K.S.; Asryan, G.; Dashyan, N.B.
2006-01-01
We report results from an experiment measuring the semiinclusive reaction 2 H(e,e ' p s ) in which the proton p s is moving at a large angle relative to the momentum transfer. If we assume that the proton was a spectator to the reaction taking place on the neutron in deuterium, the initial state of that neutron can be inferred. This method, known as spectator tagging, can be used to study electron scattering from high-momentum (off-shell) neutrons in deuterium. The data were taken with a 5.765 GeV electron beam on a deuterium target in Jefferson Laboratory's Hall B, using the CEBAF large acceptance spectrometer. A reduced cross section was extracted for different values of final state missing mass W*, backward proton momentum p → s , and momentum transfer Q 2 . The data are compared to a simple plane wave impulse approximation (PWIA) spectator model. A strong enhancement in the data observed at transverse kinematics is not reproduced by the PWIA model. This enhancement can likely be associated with the contribution of final state interactions (FSI) that were not incorporated into the model. Within the framework of the simple spectator model, a 'bound neutron structure function' F 2n eff was extracted as a function of W* and the scaling variable x* at extreme backward kinematics, where the effects of FSI appear to be smaller. For p s >0.4 GeV/c, where the neutron is far off-shell, the model overestimates the value of F 2n eff in the region of x* between 0.25 and 0.6. A dependence of the bound neutron structure function on the neutron's 'off-shell-ness' is one possible effect that can cause the observed deviation
Exchange current contributions to quasi-elastic electron scattering
International Nuclear Information System (INIS)
Conte, J.S. Jr.
1981-01-01
Because electromagnetic interactions are weak and well understood, inelastic electron scattering has been very useful in elucidating aspects of nuclear structure. In the region of large electron energy loss, an extremely simple reaction picture (quasi-free knockout of a single nucleon or electroproduction of an isobar) and a simple nuclear model (Fermi gas) have provided both a good fit to experimental data and a dynamical determination of the nuclear Fermi momentum (k/sub F/). However, there exists an anomalous region where this picture fails. Two body correlations have not seemed to help give any better agreement. We have investigated the following questions: Do exchange current processes contribute importantly in this region. Do they help produce agreement with experiment. Also, how do they effect our previous picture of quasifree knockout. We calculate the effects of exchange currents in this region using the standard Feynman graph rules. We have included all important long range exchange currents: pair, pionic, and isobar exchange currents. We found it necessary to make non-relativistic reductions of these currents in order to facilitate calculations. The resulting multidimensional integrals were done using Monte Carlo techniques. All exchange currents which were investigated were found to be appreciable in the anomalous region, and also important in the quasi-free peak region. Inclusion of these amplitudes would supply all of the missing cross section in the anomalous region: however, it would destroy the agreement between theory and experiment in the region of the quasi-free nucleon peak, and thereby cast suspicion on the aforementioned dynamical determination of k/sub F/
International Nuclear Information System (INIS)
Blais, N.; Podgorsak, E.B.
1992-01-01
A method for determining the kinetic energy of clinical electron beams is described, based on the measurement in air of the spatial spread of a pencil electron beam which is produced from the broad clinical electron beam. As predicted by the Fermi-Eyges theory, the dose distribution measured in air on a plane, perpendicular to the incident direction of the initial pencil electron beam, is Gaussian. The square of its spatial spread is related to the mass angular scattering power which in turn is related to the kinetic energy of the electron beam. The measured spatial spread may thus be used to determine the mass angular scattering power, which is then used to determine the kinetic energy of the electron beam from the known relationship between mass angular scattering power and kinetic energy. Energies obtained with the mass angular scattering power method agree with those obtained with the electron range method. (author)
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
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
Electronic structure of the palladium hydride studied by compton scattering
Mizusaki, S; Yamaguchi, M; Hiraoka, N; Itou, M; Sakurai, Y
2003-01-01
The hydrogen-induced changes in the electronic structure of Pd have been investigated by Compton scattering experiments associated with theoretical calculations. Compton profiles (CPs) of single crystal of Pd and beta phase hydride PdH sub x (x=0.62-0.74) have been measured along the [100], [110] and [111] directions with a momentum resolution of 0.14-0.17 atomic units using 115 keV x-rays. The theoretical Compton profiles have been calculated from the wavefunctions obtained utilizing the full potential linearized augmented plane wave method within the local density approximation for Pd and stoichiometric PdH. The experimental and the theoretical results agreed well with respect to the difference in the CPs between PdH sub x and Pd, and the anisotropy in the CPs of Pd or PdH sub x. This study provides lines of evidence that upon hydride formation the lowest valance band of Pd is largely modified due to hybridization with H 1s-orbitals and the Fermi energy is raised into the sp-band. (author)
Calculation of Ax for the Proton–Deuteron Breakup Reaction at 135 MeV
International Nuclear Information System (INIS)
Eslami-Kalantari, M.; Amir-Ahmadi, H.R.; Biegun, A.; Joulaeizadeh, L.; Kalantar-Nayestanaki, N.; Mardanpour, H.; Messchendorp, J.G.; Moeini, H.; Shende, S.V.; Ramazani-Moghaddam-Arani, A.; Shafaei, M.A.; Mehmandoost-Khajeh-Dad, A.A.; Gašparic, I.; Kistryn, St.; Sworst, R.; Kozela, A.; Stephan, E.
2013-01-01
Observables in proton–deuteron scattering are sensitive probes of the nucleon-nucleon interaction and three-nucleon force effects (3NF). Several facilities in the world, including Kernfysisch Versneller Instituut (KVI), allow a detailed study a few-nucleon interaction below the pion-production threshold exploiting polarized proton and deuteron beams. In this contribution we explored 3NF effects in the break-up scattering process by performing a measurement of differential cross section and the analyzing power, especially the x component of the analyzing power, using a 135 MeV polarized-proton beam impinging on a liquid-deuteron target. The proton–deuteron breakup reaction leads to a final state with three free particles and a rich phase space that allows us to study observables for continuous set of kinematical configurations of the outgoing nucleons. The results are interpreted with the help of state-of-the-art Faddeev calculations. (author)
International Nuclear Information System (INIS)
Al-Khamiesi, I.M.; Kerimov, B.K.
1988-01-01
Second Born approximation corrections to electron scattering by nuclei with arbitrary spin are considered. Explicit integral expressions for the charge, magnetic dipole and interference differential cross sections are obtained. Magnetic and interference relative corrections are then investigated in the case of backward electron scattering using shell model form factors for nuclear targets 9 Be, 10 B, and 14 N. To understand exponential growth of these corrections with square of the electron energy K 0 2 , the case of electron scattering by 6 Li is considered using monopole model charge form factor with power-law asymptotics. 11 refs., 2 figs. (author)
Energy Technology Data Exchange (ETDEWEB)
Follett, R. K., E-mail: rfollett@lle.rochester.edu; Delettrez, J. A.; Edgell, D. H.; Henchen, R. J.; Katz, J.; Myatt, J. F.; Froula, D. H. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623 (United States)
2016-11-15
Collective Thomson scattering is a technique for measuring the plasma conditions in laser-plasma experiments. Simultaneous measurements of ion-acoustic and electron plasma-wave spectra were obtained using a 263.25-nm Thomson-scattering probe beam. A fully reflective collection system was used to record light scattered from electron plasma waves at electron densities greater than 10{sup 21} cm{sup −3}, which produced scattering peaks near 200 nm. An accurate analysis of the experimental Thomson-scattering spectra required accounting for plasma gradients, instrument sensitivity, optical effects, and background radiation. Practical techniques for including these effects when fitting Thomson-scattering spectra are presented and applied to the measured spectra to show the improvements in plasma characterization.
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)
Modification of diode characteristics by electron back-scatter from high-atomic-number anodes
International Nuclear Information System (INIS)
Mosher, D.; Cooperstein, G.; Rose, D.V.; Swanekamp, S.B.
1996-01-01
In high-power vacuum diodes with high-atomic-number anodes, back-scattered electrons alter the vacuum space charge and resulting electron and ion currents. Electron multiple back-scattering was studied through equilibrium solutions of the Poisson equation for 1-dimensional, bipolar diodes in order to predict their early-time behavior. Before ion turn-on, back-scattered electrons from high-Z anodes suppress the diode current by about 10%. After ion turn-on in the same diodes, electron back-scatter leads to substantial enhancements of both the electron and ion currents above the Child-Langmuir values. Current enhancements with ion flow from low-Z anodes are small. (author). 5 figs., 7 refs
Modification of diode characteristics by electron back-scatter from high-atomic-number anodes
Energy Technology Data Exchange (ETDEWEB)
Mosher, D; Cooperstein, G [Naval Research Laboratory, Washington, DC (United States); Rose, D V; Swanekamp, S B [JAYCOR, Vienna, VA (United States)
1997-12-31
In high-power vacuum diodes with high-atomic-number anodes, back-scattered electrons alter the vacuum space charge and resulting electron and ion currents. Electron multiple back-scattering was studied through equilibrium solutions of the Poisson equation for 1-dimensional, bipolar diodes in order to predict their early-time behavior. Before ion turn-on, back-scattered electrons from high-Z anodes suppress the diode current by about 10%. After ion turn-on in the same diodes, electron back-scatter leads to substantial enhancements of both the electron and ion currents above the Child-Langmuir values. Current enhancements with ion flow from low-Z anodes are small. (author). 5 figs., 7 refs.
Multiple scattering approach to the vibrational excitation of molecules by slow electrons
International Nuclear Information System (INIS)
Drukarev, G.
1976-01-01
Another approach to the problem of vibrational excitation of homonuclear two-atomic molecules by slow electrons possibly accompanied by rotational transitions is presented based on the picture of multiple scattering of an electron inside the molecule. The scattering of two fixed centers in the zero range potential model is considered. The results indicate that the multiple scattering determines the order of magnitude of the vibrational excitation cross sections in the energy region under consideration even if the zero range potential model is used. Also the connection between the multiple scattering approach and quasi-stationary molecular ion picture is established. 9 refs
Study of Cr52 and Ca40 nuclei by electron scattering
International Nuclear Information System (INIS)
Blum, Daniel
1966-01-01
As high energy electron scattering is a powerful mean to study nuclear structure, this research thesis first reports and comments results obtained while taking the Born approximation into account, and which are useful to interpret electron scattering experiments. The author describes how nucleus charge distribution parameters are obtained from these results of elastic scattering, and then addresses the case of inelastic scattering. Three nuclear models are presented. Then, after a brief presentation of the characteristics of the experimental installation, the author describes how raw results are processed to obtain cross sections, and discusses errors. The last parts address the study of chromium 52 and calcium 40 nuclei
Mikheyev-Smirnov-Wolfenstein effect in electron-neutrino scattering experiments
International Nuclear Information System (INIS)
Bahcall, J.N.; Gelb, J.M.; Rosen, S.P.
1987-01-01
We calculate the influence of resonant neutrino scattering [the Mikheyev-Smirnov-Wolfenstein (MSW) effect] in the Sun and in the Earth on measurable quantities in solar-neutrino--electron scattering experiments. The MSW effect reduces the expected rate for 8 B-neutrino--electron scattering by a factor that ranges from --0.8 to --0.2 if resonant scattering is the correct explanation for the discrepancy between observation and calculation in the /sup 37/Cl experiment. The Earth can produce a significant diurnal effect for certain values of the neutrino mixing angle and mass difference
Deuteron forward photodisintegration: meson currents and relativity
International Nuclear Information System (INIS)
Friar, J.L.
1983-01-01
The few-nucleon problem in nuclear physics and the few-electron problem in atomic physics are shown to possess similarities. Relativistic aspects of the latter are reviewed. The radiative decay of the 3 P 1 excited state of helium-like ions to the 1 S 0 ground state is shown to be a theoretical analogue of low-energy deuteron forward photodisintegration. Both have large relativistic components. The extended Siegert's theorem, which permits application of Siegert's technique to arbitrary photon wave lengths, is applied to both transitions. Physical arguments for the two processes are stressed, and the relevance of interaction currents is discussed. 28 references
Two-component scattering model and the electron density spectrum
Zhou, A. Z.; Tan, J. Y.; Esamdin, A.; Wu, X. J.
2010-02-01
In this paper, we discuss a rigorous treatment of the refractive scintillation caused by a two-component interstellar scattering medium and a Kolmogorov form of density spectrum. It is assumed that the interstellar scattering medium is composed of a thin-screen interstellar medium (ISM) and an extended interstellar medium. We consider the case that the scattering of the thin screen concentrates in a thin layer represented by a δ function distribution and that the scattering density of the extended irregular medium satisfies the Gaussian distribution. We investigate and develop equations for the flux density structure function corresponding to this two-component ISM geometry in the scattering density distribution and compare our result with the observations. We conclude that the refractive scintillation caused by this two-component ISM scattering gives a more satisfactory explanation for the observed flux density variation than does the single extended medium model. The level of refractive scintillation is strongly sensitive to the distribution of scattering material along the line of sight (LOS). The theoretical modulation indices are comparatively less sensitive to the scattering strength of the thin-screen medium, but they critically depend on the distance from the observer to the thin screen. The logarithmic slope of the structure function is sensitive to the scattering strength of the thin-screen medium, but is relatively insensitive to the thin-screen location. Therefore, the proposed model can be applied to interpret the structure functions of flux density observed in pulsar PSR B2111 + 46 and PSR B0136 + 57. The result suggests that the medium consists of a discontinuous distribution of plasma turbulence embedded in the interstellar medium. Thus our work provides some insight into the distribution of the scattering along the LOS to the pulsar PSR B2111 + 46 and PSR B0136 + 57.
The dispersion relation for the forward elastic electron-atom scattering amplitude
International Nuclear Information System (INIS)
Amusia, M.Y.
1978-01-01
The analytical properties of forward elastic electron-atom scattering amplitude are discussed. It is noted that the occurrence of exchange between the incoming and atomic electrons leads to the appearance of a number of singularities on the negative real axis in the complex energy plane. The conclusion is drawn that the dispersion relation for the forward electron-atom scattering amplitude should also include an integration over the negative energy from - I to - infinity, where I is the ionization potential. (author)
Schmidt, A.; O'Connor, C.; Bernauer, J. C.; Milner, R.
2018-01-01
The OLYMPUS experiment measured the cross-section ratio of positron-proton elastic scattering relative to electron-proton elastic scattering to look for evidence of hard two-photon exchange. To make this measurement, the experiment alternated between electron beam and positron beam running modes, with the relative integrated luminosities of the two running modes providing the crucial normalization. For this reason, OLYMPUS had several redundant luminosity monitoring systems, including a pair of electromagnetic calorimeters positioned downstream from the target to detect symmetric Møller and Bhabha scattering from atomic electrons in the hydrogen gas target. Though this system was designed to monitor the rate of events with single Møller/Bhabha interactions, we found that a more accurate determination of relative luminosity could be made by additionally considering the rate of events with both a Møller/Bhabha interaction and a concurrent elastic ep interaction. This method was improved by small corrections for the variance of the current within bunches in the storage ring and for the probability of three interactions occurring within a bunch. After accounting for systematic effects, we estimate that the method is accurate in determining the relative luminosity to within 0.36%. This precise technique can be employed in future electron-proton and positron-proton scattering experiments to monitor relative luminosity between different running modes.
The spin structure of the deuteron
Energy Technology Data Exchange (ETDEWEB)
Frois, B. [DAPNIA/SPHN, Gif-sur-Yvette (France)
1994-12-01
The Spin Muon Collaboration (SMC) has measured for the first time the spin-dependent structure function g{sub 1}{sup d} of the deuteron in the deep inelastic scattering of polarized muons on polarized deuterons in the kinematic range Q{sup 2} > 1 GeV{sup 2}, 0.006 < x < 0.6. The first moment {Gamma}{sub 1}{sup d} = {integral}{sub 0}{sup 1}g{sub 1}{sup d}dx = 0.023 {+-} 0.020(stat.) {+-} 0.015(syst.) is smaller than the prediction of the Ellis-Jaffe sum rules. The author finds that the fraction of the nucleon spin carried by strange quarks {Delta}s is appreciable and negative. Using earlier measurements of g{sub 1}{sup p}, the group can infer the first moment of the spin-dependent neutron structure function g{sub 1}{sup n}. The combined analysis of all the available data on the spin-dependent structure functions of the nucleon shows an excellent agreement among the data sets. The author does not find significant deviations from the prediction of the Bjorken sum rule.
Multi-GeV electron-positron beam generation from laser-electron scattering.
Vranic, Marija; Klimo, Ondrej; Korn, Georg; Weber, Stefan
2018-03-16
The new generation of laser facilities is expected to deliver short (10 fs-100 fs) laser pulses with 10-100 PW of peak power. This opens an opportunity to study matter at extreme intensities in the laboratory and provides access to new physics. Here we propose to scatter GeV-class electron beams from laser-plasma accelerators with a multi-PW laser at normal incidence. In this configuration, one can both create and accelerate electron-positron pairs. The new particles are generated in the laser focus and gain relativistic momentum in the direction of laser propagation. Short focal length is an advantage, as it allows the particles to be ejected from the focal region with a net energy gain in vacuum. Electron-positron beams obtained in this setup have a low divergence, are quasi-neutral and spatially separated from the initial electron beam. The pairs attain multi-GeV energies which are not limited by the maximum energy of the initial electron beam. We present an analytical model for the expected energy cutoff, supported by 2D and 3D particle-in-cell simulations. The experimental implications, such as the sensitivity to temporal synchronisation and laser duration is assessed to provide guidance for the future experiments.
International Nuclear Information System (INIS)
Schmitz, H.H.
1990-06-01
In this experiment the deuteron-electrodisintegration was measured at an average four-momentum transfer Q 2 =0.122 (GEV/c) 2 in the invariant hadronic mass range of 2.02-2.30 GeV. The outgoing proton was detected in coincidence with the scattered electron at three different adjustments of the spectrometer, which covered the proton c.m. angle Θ γp cm =0-60deg. The measured differential cross sections show the influence of the excitation of the Δ(1232)-resonance in the deuteron. The experimental values are compared to theoretical calculations which include meson exchange currents, final state interactions and isobar contributions. (orig.)
Electron scattering by native defects in III-V nitrides and their alloys
International Nuclear Information System (INIS)
Hsu, L.; Walukiewicz, W.
1996-03-01
We have calculated the electron mobilities in GaN and InN taking into consideration scattering by short range potentials, in addition to all standard scattering mechanisms. These potentials are produced by the native defects which are responsible for the high electron concentrations in nominally undoped nitrides. Comparison of the calculated mobilities with experimental data shows that scattering by short range potentials is the dominant mechanism limiting the electron mobilities in unintentionally doped nitrides with large electron concentrations. In the case of Al x Ga 1-x N alloys, the reduction in the electron concentration due to the upward shift of the conduction band relative to the native defect level can account for the experimentally measured mobilities. Resonant scattering is shown to be important when the defect and Fermi levels are close in energy
Anti-deuteron sensitivity studies at LHCb
Baker, Sophie Katherine
2018-01-01
Measurements of anti-deuterons in collider experiments can help to reduce systematic uncertainties in indirect searches for dark matter. Two predominant unknowns in these searches are the production of secondary anti-deuterons in the cosmos from spallation processes, and anti-deuteron production from annihilating dark matter. LHCb is a forward spectrometer on the LHC ring, designed to measure b-hadron decays from high energy proton-proton collisions. With the detector's excellent particle identification capabilities, deuteron and anti-deuteron measurements at LHCb could help to parametrise the two cosmological processes. Recent studies of (anti-)deuteron identification at LHCb and the prospects for measuring prompt (anti-)deuterons from pp-collisions will be presented, as well as a working analysis of b-baryrons decaying to deuterons.
Electron scattering in large water clusters from photoelectron imaging with high harmonic radiation.
Gartmann, Thomas E; Hartweg, Sebastian; Ban, Loren; Chasovskikh, Egor; Yoder, Bruce L; Signorell, Ruth
2018-06-06
Low-energy electron scattering in water clusters (H2O)n with average cluster sizes of n < 700 is investigated by angle-resolved photoelectron spectroscopy using high harmonic radiation at photon energies of 14.0, 20.3, and 26.5 eV for ionization from the three outermost valence orbitals. The measurements probe the evolution of the photoelectron anisotropy parameter β as a function of cluster size. A remarkably steep decrease of β with increasing cluster size is observed, which for the largest clusters reaches liquid bulk values. Detailed electron scattering calculations reveal that neither gas nor condensed phase scattering can explain the cluster data. Qualitative agreement between experiment and simulations is obtained with scattering calculations that treat cluster scattering as an intermediate case between gas and condensed phase scattering.
Electron Raman scattering in semiconductor quantum wire in an external magnetic field
International Nuclear Information System (INIS)
Betancourt-Riera, Ri; Nieto Jalil, J M; Riera, R; Betancourt-Riera, Re; Rosas, R
2008-01-01
The differential cross-section for an electron Raman scattering process in a semiconductor quantum wire in the presence of an external magnetic field perpendicular to the plane of confinement is calculated. We assume a single parabolic conduction band. The emission spectra for different scattering configurations and the selection rules for the processes are studied. Singularities in the spectra are found and interpreted. The electron Raman scattering studied here can be used to provide direct information about the electron band and subband structure of these confinement systems. The magnetic field distribution is considered constant with value B 0 inside the wire and zero outside
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.
Inelastic electron scattering influence on the strong coupling oxide superconductors
International Nuclear Information System (INIS)
Gabovich, A.M.; Voitenko, A.I.
1995-01-01
The superconducting order parameters Δ and energy gap Δ g are calculated taking into account the pair-breaking inelastic quasiparticle scattering by thermal Bose-excitations, e.g., phonons. The treatment is self-consistent because the scattering amplitude depends on Δ. The superconducting transition for any strength of the inelastic scattering is the phase transition of the first kind and the dependences Δ (T) and Δ g (T) tend to rectangular curve that agrees well with the experiment for high-Tc oxides. On the basis of the developed theory the nuclear spin-lattice relaxation rate R s in the superconducting state is calculated. The Hebel-Slichter peak in R s (T) is shown to disappear for strong enough inelastic scattering
International Nuclear Information System (INIS)
Breton, Vincent
1990-01-01
We have studied Coulomb effects in the electron-nucleus interaction by measuring electron and positron elastic scattering. The Coulomb field of the nucleus acts differently on theses particles because of their opposite charges. The experiment took place at the Accelerateur Lineaire de Saclay, with 450 MeV electrons and positrons. We measured the emittance of the positron and electron beams. We compared electron and positron beams having the same energy, the same emittance and the same intensity. This way, we measured positron scattering cross sections with 2 % systematic error. By comparing positron and electron elastic scattering cross sections for momentum transfers between 1 and 2 fm -1 , on a Lead 208 target, we showed that the calculations of Coulomb effects in elastic scattering are in perfect agreement with experimental results. The comparison of positron and electron elastic scattering cross sections on Carbon showed that dispersive effects are smaller than 2 % outside the diffraction minima. These two results demonstrate in a definitive way that electron scattering allows to measure charge densities in the center of nuclei with an accuracy of the order of 1 %. (author) [fr
Contribution of the Electron Scattering Process to the Broad Hα Wings
Directory of Open Access Journals (Sweden)
Sekeráš M.
2012-06-01
Full Text Available We modeled the extended wings of the OVI 1032, 1038 Å resonance lines and He II 1640 Å emission line in the spectra of Z And, AG Dra and V1016 Cyg by the electron scattering process. By this way we determined the electron temperature and the electron optical depth of the layer of electrons, through which the line photons are transferred in the direction of the observer. We derived an empirical relationship between the emission measure of the symbiotic nebula and the electron optical depth. This relationship allows us to distinguish the flux contribution in the broad Hα wings, which is due to the electron scattering and that produced by the Hα transition in the moving hydrogen plasma. For example, subtracting the electron scattering contribution from the Hα line profile leads to a reduction in the mass-loss rate by approximately 15 %.
Temporary electron localization and scattering in disordered single strands of DNA
International Nuclear Information System (INIS)
Caron, Laurent; Sanche, Leon
2006-01-01
We present a theoretical study of the effect of structural and base sequence disorders on the transport properties of nonthermal electron scattering within and from single strands of DNA. The calculations are based on our recently developed formalism to treat multiple elastic scattering from simplified pseudomolecular DNA subunits. Structural disorder is shown to increase both the elastic scattering cross section and the attachment probability on the bases at low energy. Sequence disorder, however, has no significant effect
LA phonons scattering of surface electrons in Bi2Se3
International Nuclear Information System (INIS)
Huang, Lang-Tao; Zhu, Bang-Fen
2013-01-01
Within the Boltzmann equation formalism we evaluate the transport relaxation time of Dirac surface states (SSs) in the typical topological insulator(TI) Bi 2 Se 3 due to the phonon scattering. We find that although the back-scattering of the SSs in TIs is strictly forbidden, the in-plane scattering between SSs in 3-dimensional TIs is allowed, maximum around the right-angle scattering. Thus the topological property of the SSs only reduces the scattering rate to its one half approximately. Besides, the larger LA deformation potential and lower sound velocity of Bi 2 Se 3 enhance the scattering rate significantly. Compared with the Dirac electrons in graphene, we find the scattering rate of SSs in Bi 2 Se 3 are two orders of magnitudes larger, which agree with the recent transport experiments