Yukawa's of light stringy states

TL;DR

This paper calculates Yukawa couplings involving light stringy states at D-brane intersections, revealing potential collider signatures and addressing normalization ambiguities through amplitude factorization.

Contribution

It provides the first detailed computation of tri-linear Yukawa couplings for light stringy states at D-brane intersections, considering normalization issues.

Findings

Yukawa couplings depend on intersection angles and normalization choices.

Potential collider signatures from light stringy states are identified.

Methodology involves amplitude factorization to handle vertex operator ambiguities.

Abstract

Light massive string states can appear at D-brane intersections with small angles. We compute tri-linear Yukawa couplings of such open-string states to massless ones and to one another. Due to ambiguities in the normalisation of the vertex operators, that involve twist fields, we proceed via factorization of appropriate scattering amplitudes. Some peculiar features are observed that may lead to interesting signatures at colliders in the future.