Axion Dark Radiation: Hubble Tension and Hyper-kamiokande Neutrino Experiment

Abstract

In this work, we investigate the dark sector of a supersymmetric axion model, consisting of the late-decaying gravitino/axino dark matter and axion dark radiation. In the early universe, the decay of the scalar superpartner of the axion (saxion) will produce a large amount of entropy. The additional entropy can not only dilute the relic density of the gravitino/axino dark matter to avoid overclosing the universe but also relax the constraint on the reheating temperature $T_R$ after inflation. Meanwhile, the axion dark radiation from the saxion decay will increase the effective number of neutrino species $N_{\mathrm{eff}}$, which can help to reduce the cosmological Hubble tension. In the late universe, the decay of long-lived gravitino/axino dark matter produces the axions with MeV-scale kinetic energy. We study the potential of searching for such energetic axions through the inverse Primakoff process $a+A\to \gamma +A$ in the neutrino experiments, such as Hyper-Kamiokande.

27 pages, discussions and references are added. version accepted by PRD

References in corpus (24)

• In the Realm of the Hubble tension $-$ a Review of Solutions
• Large Magellanic Cloud Cepheid Standards Provide a 1% Foundation for the Determination of the Hubble Constant and Stronger Evidence for Physics Beyond LambdaCDM
• Revisiting the SN1987A gamma-ray limit on ultralight axion-like particles
• On the Hubble constant tension in the SNe Ia Pantheon sample
• Early dark energy, the Hubble-parameter tension, and the string axiverse
• The Diffuse Supernova Neutrino Background
• Constraints on the Reheating Temperature in Gravitino Dark Matter Scenarios
• Late universe decaying dark matter can relieve the H_0 tension
• Prospects for Beyond the Standard Model Physics Searches at the Deep Underground Neutrino Experiment
• Early mass varying neutrino dark energy: Nugget formation and Hubble anomaly
• Axinos as Dark Matter Particles
• Inverse Primakoff Scattering as a Probe of Solar Axions at Liquid Xenon Direct Detection Experiments
• Warm Decaying Dark Matter and the Hubble Tension
• A common origin of muon g-2 anomaly, Galaxy Center GeV excess and AMS-02 anti-proton excess in the NMSSM
• Constraints on the axion-electron coupling for solar axions produced by Compton process and bremsstrahlung
• Gravitino or Axino Dark Matter with Reheat Temperature as high as $10^{16}$ GeV
• Cluster X-ray line at $3.5\mathrm{keV}$ from axion-like dark matter
• Light gravitino dark matter: LHC searches and Hubble tension
• Solving Cosmological Problems of Supersymmetric Axion Models in an Inflationary Universe
• Decaying dark matter, the $H_0$ tension, and the lithium problem
• Atomic Form Factors and Inverse Primakoff Scattering of Axion
• Probing GeV-scale MSSM neutralino dark matter in collider and direct detection experiments
• Mixed axion/gravitino dark matter from SUSY models with heavy axinos
• Terrestrial Probes of Electromagnetically Interacting Dark Radiation

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• Seven hints that early-time new physics alone is not sufficient to solve the Hubble tension
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• New Physics Search at the CEPC: a General Perspective
• Polarization Signals from Axion-Photon Resonant Conversion in Neutron Star Magnetosphere
• Shining ALP Dark Radiation
• Searching for relativistic axions in the sky
• Shining Light on Cosmogenic Axions with Neutrino Experiments
• The Hubble Tension: Relativistic Dark Matter Production from Long-lived Particles