# Enhanced tensor non-Gaussianities in presence of a source

## TL;DR

This paper explores how particle production during (p)reheating can significantly enhance tensor non-Gaussianities, providing potential observational signatures of primordial gravitational waves within an effective field theory framework.

## Contribution

It introduces a model-independent approach to quantify enhanced tensor non-Gaussianities caused by sources during inflation and (p)reheating, highlighting the squeezed limit bispectrum enhancement.

## Key findings

- Tensor non-Gaussianities can be significantly amplified by sources during (p)reheating.
- Squeezed limit bispectra are more enhanced than equilateral configurations.
- The framework provides model-independent non-linearity parameters for observational tests.

## Abstract

We address the possibility of having an enhanced signal for tensor non-Gaussianities in presence of a source, as a signature of Primordial Gravitational Waves. We employ a nearly model-independent framework based on Effective Field Theory of inflation and compute tensor non-Gaussianities therefrom sourced by particle production during (p)reheating to arrive at an enhanced signal strength. We obtain the model-independent non-linearity parameters and also find that squeezed limit bispectra are more enhanced than equilateral limit.