Detonations and deflagrations in cosmological phase transitions

TL;DR

This paper analyzes the dynamics of bubble walls during cosmological phase transitions, calculating their velocities and conditions for detonations or deflagrations, with applications to extended Standard Model scenarios.

Contribution

It provides a numerical and analytical study of bubble wall velocities considering fluid dynamics and applies it to a specific particle physics model.

Findings

Identifies parameter regions allowing detonations and deflagrations.

Provides numerical calculations of wall velocities based on model parameters.

Derives analytic approximations for wall velocities in different regimes.

Abstract

We study the steady state motion of bubble walls in cosmological phase transitions. Taking into account the boundary and continuity conditions for the fluid variables, we calculate numerically the wall velocity as a function of the nucleation temperature, the latent heat, and a friction parameter. We determine regions in the space of these parameters in which detonations and/or deflagrations are allowed. In order to apply the results to a physical case, we calculate these quantities in a specific model, which consists of an extension of the Standard Model with singlet scalar fields. We also obtain analytic approximations for the wall velocity, both in the case of deflagrations and of detonations.