On Form Factors of SU(2) Invariant Thirring Model

TL;DR

This paper extends the construction of form factors in the SU(2) invariant Thirring model, introduces a new abelian symmetry, and connects to Lukyanov's operators, broadening understanding of local operators in integrable models.

Contribution

It provides integral formulae for form factors of charged local operators and uncovers a new abelian symmetry in the SU(2) invariant Thirring model.

Findings

Extended form factor formulae for charged operators

Discovered a new abelian symmetry in the model

Linked Lukyanov's operators to the symmetry structure

Abstract

Integral formulae for form factors of a large family of charged local operators in SU(2) invariant Thirring model are given extending Smirnov's construction of form factors of chargeless local operators in the sine-Gordon model. New abelian symmetry acting on this family of local operators is found. It creates Lukyanov's operators which are not in the above family of local operators in general.