The Inverse Amplitude Method and Adler Zeros

TL;DR

This paper enhances the Inverse Amplitude Method to accurately incorporate Adler zeros, improving its description of the sub-threshold region without affecting the physical predictions.

Contribution

It introduces a modification to the Inverse Amplitude Method that correctly accounts for Adler zeros, addressing a key limitation in previous implementations.

Findings

Improved the Inverse Amplitude Method to include Adler zeros

Eliminated spurious poles in the sub-threshold region

Negligible impact on physical region predictions

Abstract

The Inverse Amplitude Method is a powerful unitarization technique to enlarge the energy applicability region of Effective Lagrangians. It has been widely used to describe resonances from Chiral Perturbation Theory as well as for the Strongly Interacting Symmetry Breaking Sector. In this work we show how it can be slightly modified to account also for the sub-threshold region, incorporating correctly the Adler zeros required by chiral symmetry and eliminating spurious poles. These improvements produce negligible effects on the physical region.