Large non-Gaussianity generated at the end of Extended D-term Hybrid Inflation

TL;DR

This paper demonstrates that extending D-term hybrid inflation with a light scalar field can produce significant non-Gaussianity at the end of inflation, while also reducing cosmic string contributions to the CMB.

Contribution

It introduces a novel extension of D-term hybrid inflation that generates large non-Gaussianity and mitigates cosmic string effects on the CMB.

Findings

Large non-Gaussianity can be generated at the end of inflation.

Cosmic string contributions to the CMB can be as low as 10%.

The model can evade the spectral index problem.

Abstract

In this paper, we show that if we extend D-term hybrid inflation by adding a light scalar field which couples to a waterfall field, large non-Gaussianity can be generated at the end of inflation. Contribution of cosmic strings generated after D-term inflation to the Cosmic Microwave Background (CMB) angular power spectrum can be as low as 10% and this also evade the spectral index problem.