Oscillons in dilaton-scalar theories

TL;DR

This paper demonstrates that long-lived oscillons are common in scalar field theories coupled with a massless dilaton, including simple models, and provides analytical insights into their radiation behavior.

Contribution

It reveals the existence of long-lived oscillons in dilaton-scalar theories and analytically derives their radiation law using quasibreather concepts.

Findings

Oscillons are prevalent in dilaton-scalar theories.

Analytical radiation law for small amplitude oscillons is derived.

Oscillons are present even in simple free scalar-dilaton models.

Abstract

It is shown by both analytical methods and numerical simulations that extremely long living spherically symmetric oscillons appear in virtually any real scalar field theory coupled to a massless dilaton (DS theories). In fact such "dilatonic" oscillons are already present in the simplest non-trivial DS theory -- a free massive scalar field coupled to the dilaton. It is shown that in analogy to the previously considered cases with a single nonlinear scalar field, in DS theories there are also time periodic quasibreathers (QB) associated to small amplitude oscillons. Exploiting the QB picture the radiation law of the small amplitude dilatonic oscillons is determined analytically.