Stringy Hidden Valleys

TL;DR

This paper explores string-inspired gauge theories with hidden sectors, revealing generic features like anomalous U(1) symmetries, rich Z' boson phenomenology, and implications for dark matter and supersymmetry breaking.

Contribution

It introduces a class of quiver gauge theories motivated by string compactifications, highlighting their unique phenomenological and theoretical features.

Findings

Presence of anomalous U(1)_V symmetry affecting superpotential couplings

Rich spectrum of heavy and light Z' bosons with observable consequences

Dark matter candidates with weak interactions and potential annihilation channels

Abstract

We study gauge theories where quasi-hidden sectors are added to the MSSM for the sake of string consistency conditions which would otherwise not be satisfied. We focus on quiver gauge theories motivated by weakly coupled type II orientifold compactifications. Model independent features in this class include an anomalous U(1)_V symmetry which protects messenger masses and has strong consequences for superpotential couplings, a rich phenomenology of heavy and light Z' bosons, and axionic couplings required for anomaly cancellation via the Green-Schwarz mechanism. We discuss possibilities for dark matter and supersymmetry breaking in light of these generic features. Dark matter is necessarily non-baryonic, though many dark matter candidates have weak interactions. Most models have a U(1)_V Y Y anomaly whose cancellation requires couplings which allow for dark matter annihilation into photons through intermediate axions or anomalous Z' bosons, as in two recently proposed scenarios. There is often an additional non-anomalous U(1) symmetry which can give rise to a Fayet-like model of metastable supersymmetry breaking. Breaking of supersymmetry via SQCD can also be realized and flavor masses are often protected. Natural possibilities for mediation include gauge mediation, Z' mediation, and D-instanton mediation, though it is not possible to realize minimal gauge mediation with messengers added for string consistency.