Global View of Axion Stars with (Nearly) Planck-Scale Decay Constants

Abstract

We show that axion stars formed from axions with nearly Planck-scale decay constants $f$ are unstable to decay, and are unlikely to have phenomenological consequences. More generally, we show how results at smaller $f$ cannot be naively extrapolated to $f=\mathcal{O}(M_P)$ as, contrary to conventional wisdom, gravity and special relativity can both become relevant in the same regime. We clarify the rate of decay by reviewing and extending previous work on oscillons and axion stars, which imply a fast decay rate even for so-called dilute states at large $f$.

15 pages, 8 figures, 2 appendices. References added; updated to match published PRD version

References in corpus (20)

• GW190814: Gravitational Waves from the Coalescence of a 23 M${}_{\odot }$ Black Hole with a 2.6 M${}_{\odot }$ Compact Object
• Ultralight scalars as cosmological dark matter
• Cosmic Structure as the Quantum Interference of a Coherent Dark Wave
• Understanding the Core-Halo Relation of Quantum Wave Dark Matter, $\psi$DM, from 3D Simulations
• Dilute and dense axion stars
• Relativistic axions from collapsing Bose stars
• Quantum Radiation of Oscillons
• Subaru through a different lens: microlensing by extended dark matter structures
• Gravitational microlensing by dark matter in extended structures
• Classical Decay Rates of Oscillons
• Radio-emission of axion stars
• Axion Stars in the Infrared Limit
• Scaling relations of Fuzzy Dark Matter haloes I: individual systems in their cosmological environment
• Relaxation times for Bose-Einstein condensation in axion miniclusters
• Merger of Dark Matter Axion Clumps and Resonant Photon Emission
• Electromagnetic Bursts from Mergers of Oscillons in Axion-like Fields
• Gravitational effects on oscillon lifetimes
• Gravitational probes of ultra-light axions
• Decay of Boson Stars with Application to Glueballs and Other Real Scalars
• Optical Lensing by Axion Stars: Observational Prospects with Radio Astrometry

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• Testing multiflavored ULDM models with SPARC
• Using atomic clocks to detect local dark matter halos