The DFSZ axion in the CMB

Abstract

We perform for the first time a dedicated analysis of cosmological constraints on DFSZ QCD axion models. Such constructions are especially interesting in light of the recent Xenon-1T excess and of hints from stellar cooling. In DFSZ models, for $m_a\gtrsim 0.1$ eV, scatterings of pions and muons can produce a sizable cosmic background of thermal axions, that behave similarly to massive neutrinos. However, the pion coupling depends on the alignment between the vevs of two Higgs doublets, and can be significantly suppressed or enhanced with respect to the KSVZ scenario. Using the latest Planck and BAO data, we find $m_a\le 0.2\text{eV}$ at $95\%$ C.L., when the axion coupling to pions $c_{a\pi }$ is maximal. Constraints on $m_a$, instead, can be significantly relaxed when $c_{a\pi }$ is small. In particular, we point out that in the so-called DFSZ-II model, where the axion coupling to leptons does not vanish simultaneously with $c_{a\pi }$, production via muons gives $m_a\le 0.6\text{eV}$ at $95\%$ C.L., whereas in the DFSZ-I model bounds on $m_a$ can be fully lifted. We then combine cosmological data with recent hints of a DFSZ axion coupled to electrons from the Xenon-1T experiment, finding in this case that the axion mass is constrained to be in the window $0.07\text{eV}\lesssim m_a\lesssim 1.8(0.3)\text{eV}$ for the DFSZ-I (DFSZ-II) model. A similar analysis with stellar cooling hints gives $3\text{meV}\lesssim m_a\lesssim 0.2\text{eV}$ for DFSZ-II, while no constraint arises in the DFSZ-I case. Forthcoming CMB Stage 4 experiments will be able to further test such scenarios; for instance the Xenon-1T window should be fully probed at $2\sigma$ for a DFSZ-I axion.

arXiv comment14 pages, 10 figures

References in corpus (53)

• The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: cosmological analysis of the DR12 galaxy sample
• The Complete Light-curve Sample of Spectroscopically Confirmed Type Ia Supernovae from Pan-STARRS1 and Cosmological Constraints from The Combined Pantheon Sample
• The 6dF Galaxy Survey: Baryon Acoustic Oscillations and the Local Hubble Constant
• The Cosmic Linear Anisotropy Solving System (CLASS) II: Approximation schemes
• Large Magellanic Cloud Cepheid Standards Provide a 1% Foundation for the Determination of the Hubble Constant and Stronger Evidence for Physics Beyond LambdaCDM
• The Clustering of the SDSS DR7 Main Galaxy Sample I: A 4 per cent Distance Measure at z=0.15
• Planck 2018 results. V. CMB power spectra and likelihoods
• Conservative Constraints on Early Cosmology: an illustration of the Monte Python cosmological parameter inference code
• The landscape of QCD axion models
• The Cosmic Linear Anisotropy Solving System (CLASS) I: Overview
• Excess Electronic Recoil Events in XENON1T
• Supernova 1987A Constraints on Sub-GeV Dark Sectors, Millicharged Particles, the QCD Axion, and an Axion-like Particle
• Revisiting the bound on axion-photon coupling from Globular Clusters
• The QCD crossover at finite chemical potential from lattice simulations
• Axions from Strings: the Attractive Solution
• Neutrino and axion bounds from the globular cluster M5 (NGC 5904)
• Projected WIMP Sensitivity of the XENONnT Dark Matter Experiment
• Improved axion emissivity from a supernova via nucleon-nucleon bremsstrahlung
• The LUX-ZEPLIN (LZ) Experiment
• Pulsating white dwarfs: new insights
• Axion and neutrino bounds improved with new calibrations of the tip of the red-giant branch using geometric distance determinations
• Towards a new generation axion helioscope
• Stellar Recipes for Axion Hunters
• Thermal axion production
• Hot Axions and the $H_0$ tension
• Is there a supernova bound on axions?
• Dark matter direct search sensitivity of the PandaX-4T experiment
• A New Target for Cosmic Axion Searches
• Hadronic axion window and the big-bang nucleosynthesis
• New cosmological mass limit on thermal relic axions
• First Searches for Axions and Axion-Like Particles with the LUX Experiment
• On Axion Thermalization in the Early Universe
• New Light Species and the CMB
• Topological Susceptibility and QCD Axion Mass: QED and NNLO corrections
• Thermal axion production in the primordial quark-gluon plasma
• Cosmological Axion and neutrino mass constraints from Planck 2015 temperature and polarization data
• A viable QCD axion in the MeV mass range
• The scaling density of axion strings
• Axion hot dark matter bounds after Planck
• Primordial Black Holes from the QCD axion
• Solar axions cannot explain the XENON1T excess
• Astrophobic Axions
• Exploring New Physics with O(keV) Electron Recoils in Direct Detection Experiments
• The $H_0$ tension: $\Delta G_N$ vs. $\Delta N_{\mathrm{eff}}$
• Isocurvature Constraints and Anharmonic Effects on QCD Axion Dark Matter
• The RGB tip of galactic globular clusters and the revision of the bound of the axion-electron coupling
• Observable windows for the QCD axion through $N_{\text{eff}}$
• Ultralight Scalar Decay and the Hubble Tension
• Axions and the luminosity function of white dwarfs. The thin and thick disks, and the halo
• Axion-electron decoupling in nucleophobic axion models
• Cosmic Imprints of XENON1T Axions
• TASI Lectures on Primordial Cosmology
• Axion-electron coupling from the RGB tip of Globular Clusters

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• ALPs and HNLs at LHC and Muon Colliders: Uncovering New Couplings and Signals
• Visible GeV ALP from TeV Vector-like Leptons
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