Conformal Field Theory Couplings for Intersecting D-branes on Orientifolds

TL;DR

This paper calculates conformal field theory correlation functions for intersecting D-branes in Type II orientifolds, providing explicit Yukawa couplings and four-point interactions relevant for particle physics models.

Contribution

It offers a detailed CFT computation of correlation functions and Yukawa couplings for intersecting D-branes, including instanton effects, advancing the understanding of string-derived phenomenological models.

Findings

Explicit formulas for Yukawa couplings at D-brane intersections

Calculation of four-point correlation functions including instanton effects

Potential applications to phenomenological model building

Abstract

We present a conformal field theory calculation of four-point and three-point correlation functions for the bosonic twist fields arising at the intersections of D-branes wrapping (supersymmetric) homology cycles of Type II orientifold compactifications. Both the quantum contribution from local excitations at the intersections and the world-sheet disk instanton corrections are computed. As a consequence we obtain the complete expression for the Yukawa couplings of chiral fermions with the Higgs fields. The four-point correlation functions in turn lead to the determination of the four-point couplings in the effective theory, and may be of phenomenological interest.