Supersymmetric Flaxion

TL;DR

This paper explores supersymmetric extensions of the flaxion model, addressing flavor hierarchies, the strong CP problem, and cosmological issues, while proposing an inflationary scenario involving the flaxion multiplet.

Contribution

It introduces a supersymmetric flaxion framework that unifies flavor physics, the strong CP problem, and cosmology, including a novel inflationary model with the flaxion multiplet.

Findings

Supersymmetric flaxion models can solve flavor and strong CP problems simultaneously.

A consistent cosmological scenario including inflation, leptogenesis, and dark matter is achievable.

The model addresses cosmological issues related to gravitino and axino particles.

Abstract

Recently, a new minimal extension of the Standard Model has been proposed, where a spontaneously broken, flavor-dependent global U(1) symmetry is introduced. It not only explains the hierarchical flavor structure in the quark and lepton sector, but also solves the strong CP problem by identifying the Nambu-Goldstone boson as the QCD axion, which we call flaxion. In this work, we consider supersymmetric extensions of the flaxion scenario. We study the CP and flavor violations due to supersymmetric particles, the effects of R-parity violations, the cosmological gravitino and axino problems, and the cosmological evolution of the scalar partner of the flaxion, sflaxion. We also propose an attractor-like inflationary model where the flaxion multiplet contains the inflaton field, and show that a consistent cosmological scenario can be obtained, including inflation, leptogenesis, and dark matter.