Coulomb-nuclear interference in pion-nucleus bremsstrahlung

TL;DR

This paper investigates how Coulomb-nuclear interference affects pion-nucleus bremsstrahlung, focusing on the modification of the single-photon exchange amplitude and the interference term, which are crucial for extracting pion structure functions.

Contribution

It provides a detailed analysis of Coulomb-nuclear interference effects in pion-nucleus bremsstrahlung, enhancing understanding of background contributions in pion structure measurements.

Findings

Coulomb-nuclear interference significantly alters bremsstrahlung cross sections.

Multiple-Coulomb scattering modifies the single-photon exchange amplitude.

Interference effects must be carefully accounted for in experimental analyses.

Abstract

Pion-nucleus bremsstrahlung offers a possibility of measuring the structure functions of pion-Compton scattering from a study of the small-momentum-transfer region where the bremsstrahlung reaction is dominated by the single-photon-exchange mechanism. The corresponding cross-section distribution is characterized by a sharp peak at small momentum transfers. But there is also a hadronic contribution which is smooth and constitutes an undesired background. In this communication the modification of the single-photon exchange amplitude by multiple-Coulomb scattering is investigated as well as the Coulomb-nuclear interference term.