Maximally Helicity Violating Disk Amplitudes, Twistors and Transcendental Integrals

TL;DR

This paper derives simple, transcendental integral expressions for tree-level maximally helicity violating amplitudes of N gauge bosons in open superstring theory, utilizing dual momentum twistors and a specific computational prescription.

Contribution

It introduces a new formulation of MHV amplitudes in terms of hypergeometric integrals and dual momentum twistors, highlighting their transcendental nature.

Findings

Explicit formulas for MHV amplitudes using hypergeometric integrals

Identification of the transcendental character of the integrals

Application of Berkovits and Maldacena's prescription to compute amplitudes

Abstract

We obtain simple expressions for tree-level maximally helicity violating amplitudes of N gauge bosons from disk world-sheets of open superstrings. The amplitudes are written in terms of (N-3)! hypergeometric integrals depending on kinematic parameters, weighted by certain kinematic factors. The integrals are transcendental in a strict sense defined in this work. The respective kinematic factors can be succinctly written in terms of "dual" momentum twistors. The amplitudes are computed by using the prescription proposed by Berkovits and Maldacena.