# Properties of oscillons in hilltop potentials: energies, shapes, and lifetimes

## TL;DR

This paper investigates the properties of oscillons in hilltop potentials, focusing on their energies, shapes, and lifetimes through lattice simulations and analytical approximations, revealing their stability and dynamic behaviors.

## Contribution

It provides the first detailed analysis of oscillon characteristics in hilltop potentials, including their typical energies, shapes, and decay times, using both numerical simulations and analytical models.

## Key findings

- Oscillons can live up to 4-5 e-folds before decaying.
- Their lifetimes depend on initial shapes and model parameters.
- Breathing modes correlate with shorter oscillon lifetimes.

## Abstract

Oscillons are spatially localised strong fluctuations of a scalar field. They can e.g. form after inflation when the scalar field potential is shallower than quadratic away from the minimum. Although oscillons are not protected by topology, they can be remarkably stable and have a significant impact on the (p)reheating phase. In this work we investigate the properties of oscillons in hilltop-shaped potentials, in particular the typical energies, shapes and lifetimes. In the first part of the paper, we simulate oscillon creation and stabilization with (3+1)-dimensional classical lattice simulations, and extract the typical energies, radii and amplitudes of the oscillons. In the second part we approximate the oscillons as spherically symmetric, and simulate single oscillons until their decay. We find that typical oscillons live up to about 4-5 e-folds, with the individual lifetime of the oscillons depending mainly on the initial shape of the oscillon and the power-law coefficient characterising the particular hilltop model. We also observe a breathing mode in the oscillon radii and amplitudes, and find that stronger breathing implies shorter lifetimes.