A Light Supersymmetric Axion in an Anomalous Abelian Extension of the Standard Model

TL;DR

This paper introduces a supersymmetric extension of the Standard Model featuring an anomalous U(1) symmetry and axions, which impacts dark matter and axion phenomenology, with potential implications for string theory signatures.

Contribution

It presents a novel supersymmetric model with an anomalous U(1) and Stueckelberg axions, generalizing non-supersymmetric constructions and exploring axion properties and dark matter implications.

Findings

The model includes a light axion-like particle with variable mass.

Modification of the dark matter sector involves axions and neutralinos.

The anomalous symmetry allows unique axion-gauge field interactions.

Abstract

We present a supersymmetric extension of the Standard Model (USSM-A) with an anomalous U(1) and Stueckelberg axions for anomaly cancellation, generalizing similar non-supersymmetric constructions. The model, built by a bottom-up approach, is expected to capture the low-energy supersymmetric description of axionic symmetries in theories with gauged anomalous abelian interactions, previously explored in the non-supersymmetric case for scenarios with intersecting branes. The choice of a USSM-like superpotential, with one extra singlet superfield and an extra abelian symmetry, allows a physical axion-like particle in the spectrum. We describe some general features of this construction and in particular the modification of the dark-matter sector which involves both the axion and several neutralinos with an axino component. The axion is expected to be very light in the absence of phases in the superpotential but could acquire a mass which can also be in the few GeV range or larger. In particular, the gauging of the anomalous symmetry allows independent mass/coupling interaction to the gauge fields of this particle, a feature which is absent in traditional (invisible) axion models. We comment on the general implications of our study for the signature of moduli from string theory due to the presence of these anomalous symmetries.