Quasi-Classical and Classical Cross Sections for the Scattering of Electrons on the Coulomb Cut-Off Potential

The elastic scattering of electrons on the cut-off Coulomb potential U_c(r) = ?1/r + 1/r_c, for r ≦ r_c and U_c(r) = 0, for r > r_c, has been considered. It has been shown that for ε > 0.5/r_c (ε is the energy of free electrons in atomic units) the analytical quasi-classical expressions describe quite well the behaviour of transport, differential and total cross sections for elastic scattering. It has been shown moreover, that in the energy range considered, transport cross section could be determined with practically the same accuracy already by means of classical, analytical expressions. Born approximations show larger deviations from exact quantum calculations.     

Study of Kaon-Proton Elastic Scattering at High Energies

It ia shown that the differential cross section for both K⁺p and K^-p elastic scattering including the most recent measurements for 20 < pL < 200 (GeV/c) and with -t extended upto 28 (GeV/c)² can be fitted by using the pomeron as dipole and p as a simple pole. The difference of the total cross section for K⁺p and K^-p scattering is also explained.     

Pion-Nucleon Scattering Experiments at Low Energies

Pion-nucleon scattering and charge-exchange experiments aim at a determination of the pion-nucleon coupling constant, the sigma term of chiral symmetry breaking in non-perturbative QCD and the possible isospin breaking of strong interactions. A review of the present situation shows that the accuracy of the results is still limited by the existing data base despite 20 years of experimental efforts at meson factories. The present new generation of experiments at PSI and TRIUMF, using novel instrumentation, promises considerable progress.     

Low Energy Scattering of Electrons by Sodium

The low energy scattering of electrons by sodium at incident energies up to ionization threshold are calculated by applying the momentum space coupled-channel-optical （CCO） method. The present results are in good agreement with the previous experimental and theoretical results. Furthermore, three resonances in the total cross sections observed by previous experiments are proved by the present calculation.     

Virtual Compton Scattering off Spin-Zero Particles at Low Energies

We discuss the low-energy behaviour of the virtual Compton scattering amplitude off a spin-zero target. We first compare various methods of obtaining a low-energy expression based either on the soft-photon approximation or the use of Ward-Takahashi identities. We point out that structure-dependent terms are defined with respect to a low-energy approximation of the pole terms, which commonly is separated from the full amplitude. We derive a general expression for the structure-dependent terms in an expansion in terms of the momenta and of the initial and final virtual photon, respectively, up to and including terms of order . At order two terms appear that are related to the usual electric and magnetic polarizabilities of real Compton scattering. At order we find nine new structures of which five can only be determined using virtual photons. Received October 23, 1997; accepted for publication December 29, 1997     

Coulomb Effect on Inelastic Scattering of Proton on Deformed Nuclei at High Energies

In this paper, by using the collective coordinate of A. Bohr and phenomenological deformed optical potential and Coulomb interaction, the scattering amplitude of two composite particle systems can be obtained. The differential cross sections for the 0⁺, 2⁺, 4⁺ and 6⁺, p(0.8 GeV)+¹⁵⁴Sm and p (0.8 Gev)+¹⁷⁶Yb are calculated. The results show that the Coulomb effect is quite important.     

低能电子在水中的弹性散射

基于平均散射截面概念,结合Mott截面,计算E≤10 keV范围低能电子在水中弹性散射的微分散射截面、总散射截面及弹性散射角概率分布,与应用Rutherford模型的计算结果及实验结果符合较好.在此基础上,给出一个低能电子在水中弹性散射的模拟方法,既严格可靠,又能够方便地应用于低能电子在水中径迹结构的模拟.     

Elastic Scattering of Polarized Neutrons by 3He at Low Energy

Elastic scattering by ³He for 1.67, 2.43, 3.0, 3.4 and 7.8 MeV neutron beams of known polarization was measured at seven angles from 25° to 155° using a high pressure gas scintillation counter. The geometrical and multiple scattering effects were accounted for by the Monte Carlo technique. The corrected results were compared with previous experimental data and with the existing predictions based on microscopic calculations and phenomenological analyses.     

Relativistic Scattering States of Coulomb Potential Plus a New Ring-Shaped Potential

In this paper, exact solutions of scattering states of the Klein-Gordon equation with Coulomb potential plus a new ring-shaped potential are studied under the condition that the scalar potential is equal to the vector potential. The normalized wave functions of scattering states on the “k/2π scale” and the calculation formula of phase shifts are presented. Analytical properties of the scattering amplitude are discussed.     

Low Energy D(p, p)D Elastic Scattering Including Coulomb Force

The motivation of this paper is to obtain the three-body amplitudes for the Coulomb potential plus a nuclear force in momentum space. Not only the two-body off-shell nuclear amplitude but also the two-body off-shell Coulomb amplitude is important in the three-body calculation. For calculating the Coulomb amplitude, the modified Coulomb potential whose Fourier transformation is analytically equivalent to the pure configuration space Coulomb potential, is introduced. In addition, the decisive screening range parameter is also utilized instead of the screening range. The modified Coulomb potential plus the parameter is called decisive modified Coulomb potential. The three-body proton-deuteron elastic scattering is calculated by using the proper two-body off-shell amplitude for the decisive modified Coulomb potential.     

中能区反质子与核的非弹性散射

运用多次散射理论的光学势获得反质子的扭曲波.在扭曲波冲量近似下,讨论了中能区反质子与原子核的非弹性散射.考虑了反质子能量从180MeV到1800MeV这一能区¹²C,的2+,3-态微分截面.在这一能区的低能端,(E=180MeV)DWIA能够很好的符合实验,同时,预示了更高能量可能出现的微分截面的理论结果.     

Antiproton-Nucleus Inelastic Scattering at Intermediate Energies

The distorted wave of antiproton is obtained by an optical potential derived from the multiple scattering theory In the framework of the distorted wave impulseapproximation, we discuss the antiproton-nucleus inelastic scattering at intermediate energies. The inelastic differential cross sections of 2+, 3- states at antiproton energies from 180 MeV to 1800 MeV are calculated. It is shown that DWIA fitted the experimented data quite well, and theoretical results of inelastic cross sections at higher energies are predicted.     

Classical Scattering in the Covariant Two-Body Coulomb Potential

The problem of two relativistically-moving pointlike particles of constant mass is undertaken in an arbitrary Lorentz frame using the classical Lagrangian mechanics of Stückelberg, Horwitz, and Piron. The particles are assumed to interact at events along their world lines at a common world time, an invariant dynamical parameter which is not in general synchronous with the particle proper time. The Lorentz-scalar interaction is assumed to be the Coulomb potential (i.e., the inverse square spacetime potential) of the spacetime event separation. The classical orbit equations are found in 1 + 1 spacetime dimensions in the hyperbolic angle coordinates for the reduced problem. The solutions to the reduced motion in these coordinates are the spacetime generalizations of the nonrelativistic Kepler solutions. and they introduce an invariant eccentricity which is a function of other known constants of the motion for the reduced problem. Solutions compatible with physical scattering are obtained by the assumption that the eccentricity is a given function of the ratio of the particle masses.     

Scattering of electrons by a Coulomb center

New results are obtained from which it follows that systematic use of the one-to-one correspondence between a physical quantity and an operator, which permits the existence of a non-negative quantum distribution function, leads to an effective smearing of the potential and to the appearance of a form factor, i.e., to the existence of structure in the scattering center.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 16–19, April, 1980.     

Antiproton-Nucleus Interaction and Coulomb Effect at High Energies

The Coulomb effect in high energy antiproton-nucleus elastic and inelastic scattering from ¹²C and ¹⁶O is studied in the framework of Glauber multiple scattering theory for five kinetic energies ranged from 0.23 to 1.83 GeV. A microscopic shell-model nuclear wave functions, Woods-Saxon single-particle wave functions, and experimental pN amplitudes are used in the calculations. The results show that the Coulomb effect is of paramount importance for filling up the dips of differential cross sections. We claim that the present result for inelastic scattering of antiproton-¹²C is sufficiently reliable to be a guide for measurements in the very near future. We also believe that antiproton nucleus elastic and inelastic scattering may produce new information on both the nuclear structure and the antinucleon-nucleon interaction, in particular the p-neutron interaction.