Gravitational waves detectable in laser interferometers from axion-SU(2) inflation

Abstract

Chromo-natural inflation (CNI) is an inflationary model where an axion coupled with SU$(2)$ gauge fields acts as the inflaton. In CNI, the gauge fields have nonzero vacuum expectation values (VEVs), which results in the enhancement of gravitational waves (GWs). The original CNI is ruled out by the Planck observations due to the overproduction of GWs. In this work, we consider an inflationary model where the gauge fields acquire nonzero VEVs after the CMB modes exit the horizon. Moreover, we add to the model another field that dominates the universe and drives inflation after the axion starts to oscillate and the gauge field VEVs vanish. By performing numerical simulations, we find a parameter space where the enhanced GWs do not violate the CMB constraints and can be detected by the future GWs observations such as BBO and ET.

20pages, 8 figures

References in corpus (7)

• Laser Interferometer Space Antenna
• Monodromy in the CMB: Gravity Waves and String Inflation
• Improved Calculation of the Primordial Gravitational Wave Spectrum in the Standard Model
• Primordial Gravitational Waves from Axion-Gauge Fields Dynamics
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Cited by in corpus (8)

• Updated constraints on amplitude and tilt of the tensor primordial spectrum
• The non-linear dynamics of axion inflation: a detailed lattice study
• Lattice simulations of axion-U(1) inflation: gravitational waves, magnetic fields, and scalar statistics
• Misalignment production of vector boson dark matter from axion-SU(2) inflation
• Chromo-natural inflation supported by enhanced friction from Horndeski gravity
• Dark Energy with a Triplet of Classical U(1) Fields
• Constraining primordial tensor features with the anisotropies of the Cosmic Microwave Background
• Post-Inflationary Quenched Production of Axion SU(2) Dark Matter