Axion isocurvature perturbations in low-scale models of hybrid inflation

2018/06/30 by Kai Schmitz, Tsutomu T. Yanagida · 1 citation
Physics and Astronomy · #Anisotropy #Axion #Cosmic microwave background #Cosmic string #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Dark matter #Grand Unified Theory #Gravitino #Hidden sector #Inflation (cosmology) #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum chromodynamics #Quantum mechanics #String (physics) #Strong CP problem #Supergravity #Supersymmetry #Supersymmetry breaking #Theoretical physics #astro-ph.CO #hep-ph #hep-th

paper · pdf · doi:10.1103/physrevd.98.075003

published as Phys. Rev. D 98, 075003 (2018) · 40 pages + references, 5 figures, 1 table. v2: typos removed, updated references. v3: matches version published in PRD

openalex publication_date 2018/10/02 · arxiv created 2018/10/10 · arxiv updated 2018/10/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

The quantum chromodynamics (QCD) axion solves the strong CP problem and represents an attractive particle candidate for cold dark matter (CDM). However, quantum fluctuations of the axion field during inflation easily result in large CDM isocurvature perturbations that are in conflict with observations of the cosmic microwave background. In this paper, we demonstrate how this problem can be solved in low-scale models of hybrid inflation that may emerge from supersymmetric grand unified theories. We consider both F-term hybrid inflation and D-term hybrid inflation in supergravity, explicitly taking into account the effect of hidden-sector supersymmetry breaking. We discuss the production of cosmic strings and show how the soft terms in the scalar potential readily allow us to achieve the correct scalar spectral index. In both cases, we are able to identify large regions in parameter space that are consistent with all constraints. In particular, we find that evading the CDM isocurvature constraint always requires a small Yukawa or gauge coupling of O(10^\ensuremath-3) or smaller. This translates into upper bounds on the gravitino mass of O(10⁵) GeV in F-term hybrid inflation and O(10⁹) GeV in D-term hybrid inflation. Our results point to interesting scenarios in well-motivated parameter regions that will be tested in future axion and cosmic microwave background experiments.

Citations

• A Minimal Supersymmetric Model of Particle Physics and the Early Universe
• Simply Unnatural Supersymmetry
• A new inflationary universe scenario: A possible solution of the horizon, flatness, homogeneity, isotropy and primordial monopole problems
• WIMP dark matter from gravitino decays and leptogenesis
• A simple solution to the strong CP problem with a harmless axion
• Confronting hybrid inflation in supergravity with CMB data
• Cosmology for Grand Unified Theories with Radiatively Induced Symmetry Breaking
• Isocurvature and adiabatic fluctuations of the axion in chaotic inflation models and large scale structure
• Resonant conversions of QCD axions into hidden axions and suppressed isocurvature perturbations
• Grand unification and subcritical hybrid inflation
• Parity Conservation in Quantum Chromodynamics
• Fayet-Iliopoulos terms in string theory
• Production of dark matter axions from collapse of string-wall systems
• Possible signals of wino LSP at the Large Hadron Collider
• Supersymmetric hybrid inflation redux
• The type IIB string axiverse and its low-energy phenomenology
• The B-L Phase Transition: Implications for Cosmology and Neutrinos
• Implications of Supersymmetry Breaking with a Little Hierarchy between Gauginos and Scalars
• Topology of cosmic domains and strings
• Radiative Corrections as the Origin of Spontaneous Symmetry Breaking
• Peccei-Quinn symmetry from a gauged discreteRsymmetry
• PeV-scale supersymmetry
• Pati-Salam version of subcritical hybrid inflation
• Lattice QCD for Cosmology
• Reheating and Leptogenesis after Pati-Salam F-term Subcritical Hybrid Inflation
• Inflation from high-scale supersymmetry breaking
• New experimental approaches in the search for axion-like particles
• Planck 2015 results
• String axiverse
• Review of Multibody Charm Analyses
• Planck 2015 results. XIII. Cosmological parameters
• Planck 2015 results. XX. Constraints on inflation

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