An intermediate scale R-axion & the QCD axion

Abstract

A bstract An intermediate scale R-axion faces an immediate obstruction from the Dine-Festuccia-Komargodski (DFK) bound on the superpotential, 2|⟨ W ⟩| ≤ f R F , since for a nearly Minkowski vacuum it typically follows that f R ≳ M Pl . We show that this lower bound on f R can be relaxed in an effective construction with the scalar potential tuned near zero via a mixed F - and D -term uplift, leading to a metastable vacuum in which the usual Planckian- f R inference from the DFK argument is avoided locally. Validity of the effective field theory and metastability of the small f R vacuum generically both imply a relaxed bound: $$ {f}_R\gtrsim \sqrt{m_{3/2}{M}_{\mathrm{Pl}}} $$ f R ≳ m 3 / 2 M Pl . We also highlight that if the R-symmetry has a QCD anomaly, this potentially permits the R-axion to play the role of the QCD axion. TeV-scale supersymmetry permits f R ~ 10 11 GeV, this not only evades certain astrophysical and cosmological axion constraints, but notably lies in the window for which the observed dark matter abundance can be reproduced by the R-axion via the misalignment mechanism.