Polarization effects for elastic and inelastic scattering with an adiabatic-propagator approximation

The effective coupling potentials derived from Feshbach's projection formalism can be significantly simplified with an adiabatic approximation in the propagator. For the diagonal and non-diagonal correction terms we derive perturbation series that lead to prominent shifts in both excitation energies and transition probabilities. We give a comparison between the conventional DWBA treatment and our modified analysis for¹⁶O+¹⁶O scattering.     

On the theory of quantum interference between inelastic and elastic electron scattering events

The mechanism of weak localization of relatively fast electrons scattered with a fixed energy loss from disordered media is examined. The main focus of this paper is to put forward an explanation why coherent enhancement of electron scattering in the inelastic-scattering channel takes place at angles which differ from π. A simplified kinematic model is proposed to determine the basic properties of the weak localization of electrons in the inelastic scattering channel. The model reproduces easily the range of scattering angles typical of the weak localization of electrons with a fixed energy loss. The procedure does not require calculation of the contribution from the crossed diagrams. The results agree with those based on the dynamical theory associated with the calculation of the crossed and ladder diagrams. It is possible to follow the transition from the new type of weak localization to the ordinary weak localization with decreasing energy loss. The new-type weak localization is in agreement with the regular weak localization if the energy loss is approximately equal to the energy of an optical phonon. Zh. éksp. Teor. Fiz. 111, 1001–1015 (March 1997) Published in English in the original Russian journal. Reproduced here with stylistic changes by the Translation Editor.     

The odderon in high energy elastic pp scattering

We study the odderon contribution to elastic pp and scattering at high energies. Different models for the odderon–proton coupling are considered and their effects on the differential cross section in the dip region are investigated. We use a Regge fit by Donnachie and Landshoff as a framework and replace its odderon contribution by the different models. We consider two models for the odderon–proton impact factor proposed by Fukugita and Kwieciński and by Levin and Ryskin. In addition we construct a geometric model of the proton which allows us to put limits on the size of a possible diquark cluster in the proton. All models are able to describe the data well. The two models for the impact factor require the strong coupling constant to be fixed rather precisely. In the geometric model a relatively small diquark size is required to describe the data. Received: 1 February 2002 / Published online: 14 June 2002     

On rigid projectile approximation in high energy nucleus-nucleus scattering

Rigid projectile approximation in high energy nucleus-nucleus collisions is discussed. The results are demonstrated ond- elastic scattering.Dedicated to Professor Ivan Úlehla on the occasion of his sixtieth birthday.     

Unitary approximation for radiative high energy scattering processes: Application to Bhabha scattering

We describe how to apply the unitary approximation to high energy scattering processes which involve the radiation of arbitrarily many photons. We compare our results to calculations of inclusive quantities using leading log resummation techniques well known from QCD. In contrast to the latter method the unitary approximation is also appropriate for differential cross sections. The Monte Carlo implementation of the method is discussed and detailed results are given for the case of radiative Bhabha scattering.     

Intermediate changes in high energy elastic scattering from atoms

Correction of the Glaubner T-matrix to account for target particle motion and energy change in elastic scattering of charged particles from atomic systems is found to vanish to leading order.     

Deep inelastic scattering from quantum fluids

A simple and general argument is given for the deep inelastic behavior of the dynamic structure function of quantum fluids at zero temperature. The resulting high-energy tail is shown to give a reasonable fit to existing neutron data for liquid ⁴He.     

High energy elastic and inelastic p-12C scattering and nuclear deformation

Starting from a microscopic deformed picture of the ¹²C nucleus, and using angular momentum projected wave functions, the elastic and inelastic 1 GeV p-scattering differential cross sections have been analysed within the framework of the Glauber theory. From a comparison of the results obtained in a full Glauber calculation and in the optical limit, it has been shown that the elastic scattering and, to a lesser extent, the transition to the 2⁺(4.44 MeV) level are only weakly affected by the long-range correlations. In contrast the scattering to the 4⁺(14.08 MeV) state includes crucial multi-step contributions which affect the differential cross section both in shape and magnitude. Similarly the corrections to the DWIA are essential for the transition to the 3^?(9.64 MeV) state and a satisfactory explanation of the qualitative differences observed between the 2⁺ and 3^? inelastic cross sections in ¹²C is given. The great sensitivity of the cross sections to the nuclear deformation is shown and a generally good agreement with experiment for both the electron form factors and 1 GeV p cross sections has been obtained for the ground-state intraband transitions using a single oblate intrinsic state. The importance of a correct treatment of the rotational motion through the angular momentum projection is underlined and the use of the adiabatic approxmation is critically examined.     

A realistic complex interaction for elastic and inelastic nucleon scattering

A parameter-free microscopic calculation for the elastic and inelastic scattering of protons is presented using a complex nuclear matter t-matrix interaction which was generated from the Hamada-Johnston internucleon potential. The transitions ²⁷Al(p,n) and ⁴⁰Ca(p,p') are analyzed.     

Multi-step processes in high-energy elastic and inelastic nuclear scattering

Multi-step processes in elastic and inelastic nuclear scattering at intermediate and high energies are investigated using a formulation whereby a finite number of channels are explicitly treated while all the other channels are approximately accounted for through a “second-order potential matrix”. Within the framework of the eikonal approximation the problem reduces to a finite system of first-order coupled integro-differential equations with non-local potentials which depend on the two-body density matrix of the target nucleus. The relationship of the above formulation to the DWIA, the close-coupling method, and the Glauber multiple scattering model is examined. This approach is applied to the elastic and inelastic (2⁺, 4.43 MeV) scattering of 1 GeV nucleons by ¹²C. The corrections to the DWIA are sizeable, and the inelastic scattering appears to be very sensitive to the multi-step contributions and the nuclear structure.     

On the elastic and inelastic scattering of O

Elastic and inelastic scattering data on ¹⁷O on ⁴⁰Ca measured at E_1ab=61 MeV are analyzed using collective core contributions plus valence terms which are obtained with the microscopic single-folding model. The role of two-step transfers and reorientation processes is also assessed.     

Deformed tensor interactions in deuteron elastic and inelastic scattering

The various forms of tensor potentials present in deuteron elastic and inelastic scattering on a deformed target nucleus are derived using a folding model for the deuteron-nucleus interaction. Approximate expressions for the radial dependence of the deformed tensor interactions parametrized with the derivatives of Woods-Saxon potentials are obtained and discussed for the case of a rotational nucleus.     

A classical path approximation for diffractive surface scattering

The well-known classical path approximation is applied to a calculation of diffraction intensities in the scattering of atoms from a rigid crystal with a soft interaction potential. A general expression is derived for the diffraction intensities which can be applied to potentials with several higher-order terms in the Fourier series. For an uncorrugated Morse potential with a first-order exponential corrugation term an analytic solution is obtained which is compared with the infinite order suddent (IOS) approximation calculations for Ne/W(110) and He/LiF(100). Both approximations are very accurate for the weakly corrugated Ne/W system. For He/LiF the present approximation is more accurate than the sudden (IOS) approximation and has the added advantage of providing an analytic solution. Several improvements are suggested.