Axion Curvaton Model for the Gravitational Waves Observed by Pulsar Timing Arrays

2023/09/20 by Keisuke Inomata, Inomata, Keisuke, Masahiro Kawasaki +5 · 4 citations
Physics and Astronomy · Earth and Planetary Sciences · #Cosmology and Gravitation Theories #Pulsars and Gravitational Waves Research #Geophysics and Gravity Measurements

paper · pdf · doi:10.48550/arxiv.2309.11398

Abstract

The stochastic gravitational wave background (SGWB) recently detected by the PTA collaborations could be the gravitational waves (GWs) induced by curvature perturbations. However, primordial black holes (PBHs) might be overproduced if the SGWB is explained by the GWs induced by the curvature perturbations that follow the Gaussian distribution. This motivates models associated with the non-Gaussianity of the curvature perturbations that suppress the PBH production rate. In this work, we show that the axion curvaton model can produce the curvature perturbations that induce GWs for the detected SGWB while preventing the PBH overproduction with the non-Gaussianity.

Cited by

• Are Primordial Black Holes Truly Fine-Tuned?
• NANOGrav 15-year gravitational-wave signals from binary supermassive black-holes seeded by primordial black holes, and implications for the origins of Little Red Dots
• Stochastic Gravitational Waves from Modulated Reheating
• Understanding the Nature of Scalar-Induced Gravitational Waves

Related

• Stochastic Axion-like Curvaton: Non-Gaussianity and Primordial Black Holes Without Large Power Spectrum
• Primordial Black Holes (PBHs) and The Signatures of Cosmic Non-Gaussianity
• Induced Gravitational Waves with Kination Era for Recent Pulsar Timing Array Signals
• Detecting the Stochastic Gravitational Wave Background from Primordial Black Hole Formation
• Non-Gaussianities and Primordial Black Holes