Axions, WIMPs, proton decay and observable $r$ in $SO(10)$

Abstract

We explore some experimentally testable predictions of an $SO(10)$ axion model which includes two 10-plets of fermions in order to resolve the axion domain wall problem. The axion symmetry can be safely broken after inflation, so that the isocurvature perturbations associated with the axion field are negligibly small. An unbroken gauge $Z_2$ symmetry in $SO(10)$ ensures the presence of a stable WIMP-like dark matter, a linear combination of the electroweak doublets in the fermion 10-plets and an $SO(10)$ singlet fermion with mass $\sim 62.5\mathrm{GeV}(1\mathrm{TeV})$ when it is mostly the singlet (doublet) fermion, that co-exists with axion dark matter. We also discuss gauge coupling unification, proton decay, inflation with non-minimal coupling to gravity and leptogenesis. With the identification of the SM singlet Higgs field in the $126$ representation of $SO(10)$ as inflaton, the magnetic monopoles are inflated away, and we find $0.963\lesssim n_s\lesssim 0.965$ and $0.003\lesssim r\lesssim 0.036$, where $n_s$ and $r$ denote the scalar spectral index and tensor-to-scalar ratio, respectively. These predictions can be tested in future experiments such as CMB-S4.

21 pages, 6 figures

References in corpus (11)

• Leptogenesis
• The Well-Tempered Neutralino
• Fermion Masses in SO(10) Models
• Unification, Proton Decay and Topological Defects in non-SUSY GUTs with Thresholds
• Coleman-Weinberg Potential In Good Agreement With WMAP
• Primordial Monopoles and Strings, Inflation, and Gravity Waves
• Leptogenesis and fermion mass fit in a renormalizable $SO(10)$ model
• Inflection-point Higgs Inflation
• Superheavy WIMP dark matter from incomplete thermalization
• Gravitino constraints on supergravity inflation
• Dark Matter Detection, Standard Model Parameters, and Intermediate Scale Supersymmetry

Cited by in corpus (5)

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• A Predictive $SO(10)$ Model
• Topological structures, dark matter and gravitational waves in $E_6$
• First constraints on non-minimally coupled Natural and Coleman-Weinberg inflation and massive neutrino self-interactions with Planck+BICEP/Keck