Cosmology of an Axion-Like Majoron

Abstract

We propose a singlet majoron model that defines an inverse seesaw mechanism in the $\nu$ sector. The majoron $\varphi$ has a mass $m_{\varphi }\approx 0.5$ eV and a coupling to the $\tau$ lepton similar to the one to neutrinos. In the early universe it is initially in thermal equilibrium, then it decouples at $T\approx 500$ GeV and contributes with just $\Delta N_{\mathrm{eff}}=0.026$ during BBN. At $T=26$ keV (final stages of BBN) a primordial magnetic field induces resonant $\gamma \leftrightarrow \varphi$ oscillations that transfer 6% of the photon energy into majorons, implying $\Delta N_{\mathrm{eff}}=0.55$ and a 4.7% increase in the baryon to photon ratio. At $T\approx m_{\varphi }$ the majoron enters in thermal contact with the heaviest neutrino and it finally decays into $\nu \bar{\nu }$ pairs near recombination, setting $\Delta N_{\mathrm{eff}}=0.85$. The boost in the expansion rate at later times may relax the Hubble tension (we obtain $H_0=(71.4\pm 0.5)$ km/s/Mpc), while the processes $\nu \bar{\nu }\leftrightarrow \varphi$ suppress the free streaming of these particles and make the model consistent with large scale structure observations. Its lifetime and the fact that it decays into neutrinos instead of photons lets this axion-like majoron avoid the strong bounds that affect other axion-like particles of similar mass and coupling to photons.

23 pages, version to appear in JCAP

References in corpus (46)

• The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: cosmological analysis of the DR12 galaxy sample
• The 6dF Galaxy Survey: Baryon Acoustic Oscillations and the Local Hubble Constant
• The Cosmic Linear Anisotropy Solving System (CLASS) II: Approximation schemes
• In the Realm of the Hubble tension $-$ a Review of Solutions
• The Clustering of the SDSS DR7 Main Galaxy Sample I: A 4 per cent Distance Measure at z=0.15
• Planck 2018 results. I. Overview and the cosmological legacy of Planck
• The Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: Cosmological Implications from two Decades of Spectroscopic Surveys at the Apache Point observatory
• Dark Energy Survey Year 3 Results: Cosmological Constraints from Galaxy Clustering and Weak Lensing
• H0LiCOW XIII. A 2.4% measurement of $H_0$ from lensed quasars: $5.3\sigma$ tension between early and late-Universe probes
• Planck 2018 results. V. CMB power spectra and likelihoods
• Big Bang Nucleosynthesis: 2015
• Euclid Definition Study Report
• Conservative Constraints on Early Cosmology: an illustration of the Monte Python cosmological parameter inference code
• Cosmic Distances Calibrated to 1% Precision with Gaia EDR3 Parallaxes and Hubble Space Telescope Photometry of 75 Milky Way Cepheids Confirm Tension with LambdaCDM
• The Hubble Hunter's Guide
• 2020 Global reassessment of the neutrino oscillation picture
• Primordial Nucleosynthesis in the Precision Cosmology Era
• Astrophysical Axion Bounds
• The Cosmic Linear Anisotropy Solving System (CLASS) I: Overview
• A Search for Electron Neutrino Appearance at the Delta m**2 ~ 1 eV**2 Scale
• Revisiting the bound on axion-photon coupling from Globular Clusters
• Physics of Core-Collapse Supernovae in Three Dimensions: a Sneak Preview
• On the Hubble constant tension in the SNe Ia Pantheon sample
• Towards a precision calculation of $N_{\mathrm{eff}}$ in the Standard Model II: Neutrino decoupling in the presence of flavour oscillations and finite-temperature QED
• On Effective Degrees of Freedom in the Early Universe
• Neutrinoless double beta decay versus other probes of heavy sterile neutrinos
• Precision Early Universe Thermodynamics made simple: $N_{\mathrm{eff}}$ and Neutrino Decoupling in the Standard Model and beyond
• A CMB Search for the Neutrino Mass Mechanism and its Relation to the $H_0$ Tension
• Neutrino decoupling beyond the Standard Model: CMB constraints on the Dark Matter mass with a fast and precise $N_{\mathrm{eff}}$ evaluation
• J-PAS: The Javalambre-Physics of the Accelerated Universe Astrophysical Survey
• Signatures of a hidden cosmic microwave background
• CMB Signals of Neutrino Mass Generation
• Primordial Deuterium after LUNA: concordances and error budget
• Cosmological bounds on sub-MeV mass axions
• Self-interacting Warm Dark Matter
• Constraining resonant photon-axion conversions in the Early Universe
• The Hubble Tension as a Hint of Leptogenesis and Neutrino Mass Generation
• A near-minimal leptoquark model for reconciling flavour anomalies and generating radiative neutrino masses
• Axion Dark Matter and Cosmological Parameters
• Consistent QFT description of non-standard neutrino interactions
• Effects of heavy Majorana neutrinos on lepton flavor violating processes
• Heavy sterile neutrinos in stellar core-collapse
• CMB constraints on mass and coupling constant of light pseudoscalar particles
• Ma-xion: Majoron as QCD axion in a radiative seesaw model
• The $\rho$ parameter and $H^0\to {\ell }_i{\ell }_j$ in models with TeV sterile neutrinos
• Inverse Seesaw, dark matter and the Hubble tension

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