$A$-dependence of coherent electroproduction of $\rho^{0}$ mesons on nuclei in forward direction

TL;DR

This paper investigates how the differential cross section for coherent electroproduction of $ ho^{0}$ mesons varies with atomic mass number $A$, revealing complex behavior with minima, maxima, and breaking points in the ratio of real to imaginary parts of the amplitude.

Contribution

It provides a detailed analysis of the $A$-dependence of the cross section and the amplitude ratio, highlighting the complex behavior and correlations at specific $A$ values.

Findings

Cross section exhibits minima and maxima over $A$.

The ratio $rac{ ext{Re}f_A}{ ext{Im}f_A}$ has breaking points at certain $A$.

Minima in the cross section align with breaking points of the amplitude ratio.

Abstract

This article presents the $A$-dependence of the differential cross section for the coherent electroproduction of vector mesons on nuclei in forward direction, at fixed values of longitudinal momentum transfer $q_{L}$. It is shown that such cross section has complicated behavior over the atomic mass number $A$ with local minimums and maximums. It is also shown that a ratio of the real to the imaginary parts of the forward coherent amplitude on nuclei $\alpha_{A} = \Re e{f_{A}} / \Im m{f_{A}}$ has breaking points at some values of $A$. Comparison of the behaviors of the normalized cross section $\Big(\frac{d\sigma}{d\Omega}\Big)_{A}\Big/\Big(\frac{d\sigma}{d\Omega}\Big)_{N}$ and $\alpha_{A}$ over $A$ shows that the location of minimums of the cross section are very close to the breaking points of $\alpha_{A}$.