Radiation and Relaxation of Oscillons

TL;DR

This paper investigates the longevity and radiation emission of oscillons across different potentials, revealing potential for infinitely long-lived oscillons in convex potentials, with detailed analysis of their energy, frequency, and radiation spectra.

Contribution

It introduces a new class of convex potentials for oscillon study and demonstrates their remarkable longevity compared to traditional models.

Findings

Oscillons in convex potentials do not decay within simulation times up to 10^7 units.

Oscillons in quartic and sine-Gordon models decay relatively quickly.

Distinct frequency peaks characterize the emitted radiation spectra.

Abstract

We study oscillons, extremely long-lived localized oscillations of a scalar field, with three different potentials: quartic, sine-Gordon model and in a new class of convex potentials. We use an absorbing boundary at the end of the lattice to remove emitted radiation. The energy and the frequency of an oscillon evolve in time and are well fitted by a constant component and a decaying, radiative part obeying a power law as a function time. The power spectra of the emitted radiation show several distinct frequency peaks where oscillons release energy. In two dimensions, and with suitable initial conditions, oscillons do not decay within the range of the simulations, which in quartic theory reach 10^8 time units. While it is known that oscillons in three-dimensional quartic theory and sine-Gordon model decay relatively quickly, we observe a surprising persistence of the oscillons in the convex potential with no sign of demise up to 10^7 time units. This leads us to speculate that an oscillon in such a potential could actually live infinitely long both in two and three dimensions.