An even lighter QCD axion

Abstract

We explore whether the axion which solves the strong CP problem can naturally be much lighter than the canonical QCD axion. The $Z_{\mathcal{N}}$ symmetry proposed by Hook, with $\mathcal{N}$ mirror and degenerate worlds coexisting in Nature and linked by the axion field, is considered in terms of generic effective axion couplings. We show that the total potential is safely approximated by a single cosine in the large $\mathcal{N}$ limit, and we determine the analytical formula for the exponentially suppressed axion mass. The resulting universal enhancement of all axion interactions relative to those of the canonical QCD axion has a strong impact on the prospects of axion-like particle experiments such as ALPS II, IAXO and many others. The finite density axion potential is also analyzed and we show that the $Z_{\mathcal{N}}$ asymmetric background of high-density stellar environments sets already significant model-independent constraints: $3\le \mathcal{N}\lesssim 47$ for an axion scale $f_a\lesssim 2.4\times 10^{15}$ GeV, with tantalizing discovery prospects for any value of $f_a$ and down to $\mathcal{N}\sim 9$ with future neutron star and gravitational wave data, down to the ultra-light mass region. In addition, two specific ultraviolet $Z_{\mathcal{N}}$ completions are developed: a composite axion one and a KSVZ-like model with improved Peccei-Quinn quality.

arXiv comment35 pages and 11 figures; matches JHEP version

References in corpus (71)

• String Axiverse
• Ultralight scalars as cosmological dark matter
• New CAST Limit on the Axion-Photon Interaction
• An increased estimate of the merger rate of double neutron stars from observations of a highly relativistic system
• The QCD axion, precisely
• Exploring the String Axiverse with Precision Black Hole Physics
• The landscape of QCD axion models
• Astrophysical Axion Bounds
• Discovering the QCD Axion with Black Holes and Gravitational Waves
• Planck-Scale Physics and the Peccei-Quinn Mechanism
• The Confrontation between General Relativity and Experiment
• Solutions to the strong CP problem in a world with gravity
• Revisiting the bound on axion-photon coupling from Globular Clusters
• New ALPS Results on Hidden-Sector Lightweights
• Revisiting the SN1987A gamma-ray limit on ultralight axion-like particles
• The chiral representation of the $\pi N$ scattering amplitude and the pion-nucleon sigma term
• Any Light Particle Search II -- Technical Design Report
• X-ray Emissions from Accreting White Dwarfs: a Review
• The Early Mirror Universe: Inflation, Baryogenesis, Nucleosynthesis and Dark Matter
• High-precision determination of the pion-nucleon $\sigma$-term from Roy-Steiner equations
• Mirror dark matter: Cosmology, galaxy structure and direct detection
• New Exclusion Limits for the Search of Scalar and Pseudoscalar Axion-Like Particles from "Light Shining Through a Wall"
• Redefining the Axion Window
• Mirror World and its Cosmological Consequences
• Strong CP problem and mirror world: the Weinberg Wilczek axion revisited
• Grand unification and heavy axion
• The PVLAS experiment: measuring vacuum magnetic birefringence and dichroism with a birefringent Fabry-Perot cavity
• Anomalous solutions to the strong CP problem
• Probing axions with neutron star inspirals and other stellar processes
• A New Bound on Axion-Like Particles
• First results of the CERN Resonant WISP Search (CROWS)
• The photo-philic QCD axion
• Factoring the Strong CP Problem
• A Model of Visible QCD Axion
• The High Quality QCD Axion and the LHC
• The Fermi Large Area Telescope as a Galactic Supernovae Axionscope
• Solving the Hierarchy Problem Discretely
• Color Unifed Dynamical Axion
• A Visible QCD Axion from an Enlarged Color Group
• Poincare Protection for a Natural Electroweak Scale
• Prospects for axion searches with Advanced LIGO through binary mergers
• Experimental Targets for Photon Couplings of the QCD Axion
• Constraints on axion-like particles from X-ray observations of Hydra galaxy cluster
• Composite Accidental Axions
• Search for Axionlike-Particle-Induced Prompt Gamma-Ray Emission from Extragalactic Core-Collapse Supernovae with the Fermi Large Area Telescope
• Effects of theta on the deuteron binding energy and the triple-alpha process
• A "Gauged" $U(1)$ Peccei-Quinn Symmetry
• Accidental Peccei-Quinn symmetry protected to arbitrary order
• The strong CP problem versus Planck scale physics
• A High Quality Composite Axion
• A Composite Higgs with a Heavy Composite Axion
• A Flavorful Factoring of the Strong CP Problem
• Automatic Peccei-Quinn symmetry
• 750 GeV diphoton resonance in a visible heavy QCD axion model
• The QCD Axion at Finite Density
• Conceptual Design of a New Large Superconducting Toroid for IAXO, the New International AXion Observatory
• Mirror World, Supersymmetric Axion and Gamma Ray Bursts
• New Solutions to the Strong CP Problem
• Axion quality from the (anti)symmetric of SU(N)
• Selective enhancement of the QCD axion couplings
• The Axion Quality Problem: Global Symmetry Breaking and Wormholes
• Axions in a highly protected gauge symmetry model
• $\theta$-dependence of light nuclei and nucleosynthesis
• $B-L$ as a Gauged Peccei-Quinn Symmetry
• Accidental SO(10) axion from gauged flavour
• Gauged Peccei-Quinn Symmetry - A Case of Simultaneous Breaking of SUSY and PQ Symmetry
• Asymptotic expansions of the hypergeometric function with two large parameters $-$ application to the partition function of a lattice gas in a field of traps
• Dynamical axion misalignment with small instantons
• Flavoured Warped Axion
• Light axions with large hadronic couplings
• The Axion Mass in Modular Invariant Supergravity

Cited by in corpus (70)

• Dark matter from an even lighter QCD axion: trapped misalignment
• First Constraints on Nuclear Coupling of Axionlike Particles from the Binary Neutron Star Gravitational Wave Event GW170817
• Novel cosmological bounds on thermally-produced axion-like particles
• Stellar Evolution confronts Axion Models
• The Phenomenology of Quadratically Coupled Ultra Light Dark Matter
• Probing the Blue Axion with Cosmic Optical Background Anisotropies
• Supernova axions convert to gamma-rays in magnetic fields of progenitor stars
• Axion Astrophysics
• Axion Couplings in Grand Unified Theories
• The future search for low-frequency axions and new physics with the FLASH resonant cavity experiment at Frascati National Laboratories
• Photophilic hadronic axion from heavy magnetic monopoles
• Worldline effective field theory of inspiralling black hole binaries in presence of dark photon and axionic dark matter
• Axion Star Explosions: A New Source for Axion Indirect Detection
• Audible Axions with a Booster: Stochastic Gravitational Waves from Rotating ALPs
• First Search for Axion-Like Particles in a Storage Ring Using a Polarized Deuteron Beam
• New Limit on Axion-Like Dark Matter using Cold Neutrons
• Gamma-ray Cosmology and Tests of Fundamental Physics
• ALP Dark Matter Mini-Clusters from Kinetic Fragmentation
• Constraining Light QCD Axions with Isolated Neutron Star Cooling
• Filtered asymmetric dark matter during the Peccei-Quinn phase transition
• Cosmologically Varying Kinetic Mixing
• Detecting Axion Dark Matter with Black Hole Polarimetry
• Axion-pion thermalization rate in unitarized NLO chiral perturbation theory
• The cost of an ALP solution to the neutral $B$-anomalies
• ALP Searches at the LHC: FASER as a Light Shining through Walls Experiment
• Dark Matter Axions in the Early Universe with a Period of Increasing Temperature
• From axion quality and naturalness problems to a high-quality ${\mathbb{Z}}_N$ QCD relaxion
• Unitarity constraints on ALP interactions
• Axion Quality Problem Alleviated by Non-Minimal Coupling to Gravity
• Axion dark matter from frictional misalignment
• Probing HNL-ALP couplings at colliders
• Searching for Ultra-Light Axions with Twisted Cavity Resonators of Anyon Rotational Symmetry with Bulk Modes of Non-Zero Helicity
• The Quality/Cosmology Tension for a Post-Inflation QCD Axion
• The Any Light Particle Search experiment at DESY
• Magnetic dynamo caused by axions in neutron stars
• Discovering QCD-Coupled Axion Dark Matter with Polarization Haloscopes
• S.M.A.S.H.E.D.: Standard Model Axion Seesaw Higgs Inflation Extended for Dirac Neutrinos
• Pi in the Sky: Neutron Stars with Exceptionally Light QCD Axions
• Aspects of Axions and ALPs Phenomenology
• Kinetic Axion Dark Matter in String Corrected $f(R)$ Gravity
• A Light QCD Axion with Hilltop Misalignment
• Axion Bounds from Quantum Technology
• Nuclear decay anomalies as a signature of axion dark matter
• Discrete Goldstone Bosons
• The $\theta$-angle and axion physics of two-color QCD at fixed baryon charge. Part I
• ALPs and HNLs at LHC and Muon Colliders: Uncovering New Couplings and Signals
• Minimal Electroweak Baryogenesis via Domain Walls
• Cosmic Birefringence from CP-Violating Axion Interactions
• A Lighter QCD Axion from Anarchy
• Visible GeV ALP from TeV Vector-like Leptons
• Axion sourcing in dense stellar matter via CP-violating couplings
• Weak nuclear decays deep-underground as a probe of axion dark matter
• Sub-keV dark matter can strongly ionize molecular clouds
• Stacking the Deck: Gambling on a Light QCD Axion
• (Non-)Perturbative Dynamics of a Light QCD Axion: Dark Matter and the Strong CP Problem
• Axion Window on New Macroscopic Forces
• ALP Dark Matter from Kinetic Fragmentation: Opening up the Parameter Window
• Wideband Search for Axionlike Dark Matter Using Octupolar Nuclei in a Crystal
• The Forward Physics Facility at the High-Luminosity LHC
• Multimessenger Astronomy Beyond the Standard Model: New Window from Quantum Sensors
• Apparent $w<-1$ and a Lower $S_8$ from Dark Axion and Dark Baryons Interactions
• Supercooled Audible Axions
• One-loop corrections to ALP couplings
• One-loop corrections to ALP couplings
• Axions at the meV Crossroads: Theory, Cosmology, Astrophysics, and Experiments
• Ultralight Axions Versus Primordial Black Holes
• Axion signatures from supernova explosions through the nucleon electric-dipole portal
• Axion dark matter detection via shift current
• ALP Search Using Precessing Light in a Magnetized Fabry Perot Cavity
• Probing Quadratically Coupled Ultralight Dark Matter with Pulsar Timing Arrays