A study of form factors in relativistic mixed-flux AdS₃

We study the two-particle form-factors for the relativistic limit of the integrable S-matrix of the mixed-flux AdS₃ × S³ × T⁴ string theory. The S-matrix theory was formally constructed in two distinct ways by two different teams. We focus on the massive theory built up by Frolov, Polvara and Sfondrini, and derive expressions for the minimal solutions to the axioms, in both integral and manifestly meromorphic form, and then proceed to apply the off-shell Bethe ansatz method of Babujian et al. We obtain the integral formulas for the two-particle complete form-factors and check the axioms at this particle number.