On the electromagnetic form factors of hadrons in the time-like region near threshold

TL;DR

This paper investigates the electromagnetic form factors of hadrons near the threshold in the time-like region, linking their energy behavior to strong hadron-antihadron interactions and estimating scattering parameters.

Contribution

It introduces a method to relate the form factor behavior to hadron-antihadron interactions and estimates scattering lengths and volumes from experimental data.

Findings

Imaginary parts of scattering lengths are estimated for various hadron-antihadron pairs.

The energy dependence of form factors near threshold is characterized by strong interaction effects.

A semiphenomenological model describes form factor behavior away from the threshold.

Abstract

Hadron electromagnetic form factor in the time-like region at the boundary of the physical region is considered. The energy behavior of the form factor is shown to be determined by the strong hadron-antihadron interaction. Imaginary parts of the scattering lengths for $p\bar{p}$, $\Lambda\bar{\Lambda}$, $\Lambda\bar{\Sigma}^0 (\bar{\Lambda}{\Sigma}^0)$ and ${\Sigma}^0\bar{\Sigma}^0$ are estimated. Developed approach enables us to estimate imaginary part of the scattering volume from $D^*\bar{D^*}$ experimental data. The form factor energy behavior away from the threshold is obtained within a semiphenomenological model of hadron-antihadron interaction.