Light Front Formalism for Composite Systems and Some of Its Applications in Particle and Relativistic Nuclear Physics

TL;DR

This paper reviews the light front formalism for composite systems, deriving equations for bound states and scattering, and explores applications in particle and nuclear physics, including form factors, structure functions, and relativistic wave functions.

Contribution

It introduces methods for constructing elastic form factors and scattering amplitudes, and analyzes the impact of transverse parton motion on structure functions and scaling behaviors.

Findings

Elastic form factors calculated in impulse approximation

Transverse motion of partons affects Bjorken scaling

Scaling properties of light nuclei wave functions analyzed

Abstract

Light front formalism for composite systems is presented. Derivation of equations for bound state and scattering problems are given. Methods of constructing of elastic form factors and scattering amplitudes of composite particles are reviewed. Elastic form factors in the impulse approximation are calculated. Scattering amplitudes for relativistic bound states are constructed. Some model cases for transition amplitudes are considered. Deep inelastic form factors (structure functions) are expressed through light front wave functions. It is shown that taking into account of transverse motion of partons leads to the violation of Bjorken scaling and structure functions become square of transverse momentum dependent. Possible explanation of the EMC-effect is given. Problem of light front relativization of wave functions of lightest nuclei is considered. Scaling properties of deuteron, ${}^3He$ and ${}^4He$ light front wave functions are checked in a rather wide energy range.