More on gravitational waves from double monodromy inflation

TL;DR

This paper explores the gravitational wave signatures of double axion monodromy inflation, highlighting the coexistence of chiral and non-chiral gravitational waves and their potential detectability by future space-based interferometers.

Contribution

It demonstrates that the model predicts both chiral and non-chiral gravitational waves peaking at similar frequencies, with non-chiral waves potentially dominating away from the peak.

Findings

Chiral gravitational waves originate from gauge field instability.

Non-chiral, scalar-induced gravitational waves are also significant.

Future space-based detectors like LISA and DECIGO can probe these signals.

Abstract

We further analyze phenomenological implications of double axion monodromy inflation proposed in Ref. Phys. Rev. D 104, L081302 (2021), in gravitational wave physics. We show that in addition to chiral gravitational waves (GW) originating from gauge field instability, the model also predicts significant amount of non-chiral, scalar-induced gravitational waves, both peaking at around the same frequencies. We find that although chiral GW density has much larger peak, non-chiral GWs can dominate away from the peak as they decay at a slower rate. This provides an interesting GW signature to be probed by future space-based interferometers such as LISA and DECIGO.