Dispersion sum rules for pion polarizabilities

TL;DR

This paper analyzes dispersion sum rules for pion polarizabilities, confirming their consistency and comparing their predictions with chiral perturbation theory and experimental data.

Contribution

It demonstrates the absence of spurious singularities in dispersion sum rule approaches for pion polarizabilities.

Findings

Dispersion sum rules are free of spurious singularities.

Calculated polarizabilities agree with ChPT predictions.

Results are consistent with experimental data.

Abstract

An analysis of different dispersion sum rules (DSRs) for the dipole and quadrupole pion polarizabilities is carried out. We prove the absence of additional spurious singularities in these approaches. The results of the calculations of the polarizabilities in the framework of DSRs are compared with ChPT predictions and with data obtained in different experiments.