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.
Highlights
A new minimal extension of the Standard Model has been proposed [1, 2], where the Froggatt-Nielsen U(1) flavor symmetry [3] and the Peccei-Quinn (PQ) symmetry [4] are identified: U(1)F = U(1)PQ. (1)In this scenario, flavor dependent U(1) charges of the quarks and leptons can explain their hierarchical masses and mixings, while the Nambu-Goldstone (NG) boson of the spontaneously broken U(1) symmetry plays the role of the QCD axion [5, 6] to solve the strong CP problem as well as the dark matter puzzle [7–9]
We investigate the cosmological evolution of the sflaxion field, and show that there is a viable parameter space in which the leptogenesis can generate a sufficient amount of the baryon asymmetry
We have studied a SUSY extension of the flaxion model in which the NG boson in association with the spontaneous breaking of the U(1)F flavor symmetry plays the role of the axion
Summary
In the original (non-SUSY) flaxion scenario, the U(1) breaking field φ and the Standard Model Higgs field H can have a direct coupling as. In the SUSY flaxion model, there is a light scalar field which corresponds to the flat direction of the superpotential, sflaxion. The U(1)F-invariant superpotential for the fields in the minimal SUSY standard model (MSSM) and the right-handed neutrinos are given by. The field σ corresponds to the flat direction of the superpotential (11), which can be called as sflaxion It receives a soft mass of the order of the gravitino mass, mσ O(m3/2), after SUSY breaking.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
