Stochastic Axion Dark Matter in Axion Landscape

Abstract

We study the stochastic axion dark matter scenario in the axion landscape, where one of the axions is light and stable and therefore explains dark matter. If the axion mass at the potential is a typical value of the curvature along the direction, the potential can be well approximated by a quadratic mass term. On the other hand, if the axion mass happens to be suppressed in the vicinity of the minimum, the potential may be approximated by a quartic potential plus a suppressed quadratic one, for which the initial angle, and thus the axion abundance, can be significantly suppressed compared to the quadratic case. We delineate the viable parameter region by taking account of various observational constraints, and find that a broader range of the inflation scale is allowed. Also, if the curvature of the potential is suppressed over a certain range of the potential, the onset of coherent oscillations can be delayed. Then, the axion dark matter with a small decay constant is possible. We also discuss the πnflation mechanism to realize the hilltop initial condition in the stochastic axion scenario.

arXiv comment26 pages, 6 figures

References in corpus (59)

• A Universal Density Profile from Hierarchical Clustering
• The Structure of Cold Dark Matter Halos
• Equilibrium State of a Massless Self-Interacting Scalar Field in the De Sitter Background
• Milky Way Cepheid Standards for Measuring Cosmic Distances and Application to Gaia DR2: Implications for the Hubble Constant
• Completing Natural Inflation
• Oscillons: Resonant Configurations During Bubble Collapse
• Constraining Light Dark Matter with Diffuse X-Ray and Gamma-Ray Observations
• Conceptual Design of the International Axion Observatory (IAXO)
• Inflation and Eternal Inflation
• Oscillons After Inflation
• Pseudo-Stable Bubbles
• Science with e-ASTROGAM (A space mission for MeV-GeV gamma-ray astrophysics)
• The Large-Misalignment Mechanism for the Formation of Compact Axion Structures: Signatures from the QCD Axion to Fuzzy Dark Matter
• Natural inflation with multiple sub-Planckian axions
• The Equation of State and Duration to Radiation Domination After Inflation
• Towards a new generation axion helioscope
• The Stochastic Axion Scenario
• Thermal axion production
• The QCD Axion Window and Low Scale Inflation
• The ALP miracle: unified inflaton and dark matter
• The Cosmology of String Theoretic Axions
• Flat-top oscillons in an expanding universe
• I-balls
• Gravitational Waves from Oscillon Preheating
• Decaying dark matter and the tension in ${\sigma }_8$
• Oscillons from String Moduli
• The ALP miracle revisited
• Non-Gaussianity from Curvatons Revisited
• Gravitational wave forest from string axiverse
• Natural and Multi-Natural Inflation in Axion Landscape
• Isocurvature Constraints and Anharmonic Effects on QCD Axion Dark Matter
• K-Oscillons: Oscillons with Non-Canonical Kinetic Terms
• QCD Axion on Hilltop by a Phase Shift of $\pi$
• Cosmological Moduli Problem in Gauge-mediated Supersymmetry Breaking Theories
• Suppressing Isocurvature Perturbations of QCD Axion Dark Matter
• Axion Misalignment Driven to the Hilltop
• Decay of I-ball/Oscillon in Classical Field Theory
• ALP inflation and Big Bang on Earth
• Axion Landscape and Natural Inflation
• Relaxing the Cosmological Moduli Problem by Low-scale Inflation
• Resonant conversions of QCD axions into hidden axions and suppressed isocurvature perturbations
• Domain Wall Formation from Level Crossing in the Axiverse
• Axion Cosmology with a Stronger QCD in the Early Universe
• Level Crossing between QCD Axion and Axion-Like Particle
• Oscillons from Pure Natural Inflation
• Inflaton Condensate Fragmentation in Hybrid Inflation Models
• Enhanced photon coupling of ALP dark matter adiabatically converted from the QCD axion
• Adiabatic Invariance of Oscillons/I-balls
• Constraints on decaying dark matter from weak lensing and cluster counts
• Cosmic neutrino background search experiments as decaying dark matter detectors
• Vacuum statistics and stability in axionic landscapes
• Detecting a Secondary Cosmic Neutrino Background from Majoron Decays in Neutrino Capture Experiments
• No quasi-stable scalaron lump forms after $R^2$ inflation
• Stochastic inflation with an extremely large number of $e$-folds
• Inflaton fragmentation in E-models of cosmological $\alpha$-attractors
• Vacuum Selection on Axionic Landscapes
• Hessian eigenvalue distribution in a random Gaussian landscape
• Dark Matter in Axion Landscape
• Evidence for Inflation in an Axion Landscape

Cited by in corpus (19)

• Kilobyte Cosmic Birefringence from ALP Domain Walls
• Power spectrum of domain-wall network and its implications for isotropic and anisotropic cosmic birefringence
• Challenges for heavy QCD axion inflation
• Strong CP problem and axion dark matter with small instantons
• Cosmic Axion Force
• Scale and quality of Peccei-Quinn symmetry and weak gravity conjectures
• Cosmological effects of Peccei-Quinn symmetry breaking on QCD axion dark matter
• Trapping Effect for QCD Axion Dark Matter
• The Stochastic Axiverse
• What if ALP dark matter for the XENON1T excess is the inflaton
• The QCD Axion: A Unique Player in the Axiverse with Mixings
• Thermal production of cold "hot dark matter" around eV
• Phenomenology of CP-even ALP
• Small cosmological constant from a peculiar inflaton potential
• Hidden Dark Matter from Starobinsky Inflation
• Constraints on ultralight axions, vector gauge bosons, and unparticles from geodetic and frame-dragging measurements
• Isotropic cosmic birefringence from string axion domain walls without cosmic strings, and DESI results
• Dark Matter Freeze-In and Small-Scale Observables: Novel Mass Bounds and Viable Particle Candidates
• Emergent particles of de Sitter: thermal interpretation of the stochastic formalism and beyond