Gravitational Radiation Generated by Cosmological Phase Transition Magnetic Fields

TL;DR

This paper investigates gravitational waves produced by magnetic fields generated during cosmological phase transitions, specifically the electroweak and QCD transitions, using MHD turbulence models to predict their detectability by LISA.

Contribution

It introduces a detailed calculation of gravitational wave spectra from magnetic fields generated during early universe phase transitions, considering MSSM and QCD Lagrangians.

Findings

EW gravitational wave peak at 1-2 mHz, amplitude ~10^{-20} to 10^{-21}

QCD gravitational waves are outside LISA sensitivity

Potential detectability of EW transition signals by LISA

Abstract

We study gravitational waves generated by the cosmological magnetic fields induced via bubble collisions during the electroweak (EW) and QCD phase transitions. The magnetic field generation mechanisms considered here are based on the use of the fundamental EW minimal supersymmetric (MSSM) and QCD Lagrangians. The gravitational waves spectrum is computed using a magnetohydrodynamic (MHD) turbulence model. We find that gravitational wave spectrum amplitude generated by the EW phase transition peaks at frequency approximately 1-2 mHz, and is of the order of $10^{-20}-10^{-21}$; thus this signal is possibly detectable by Laser Interferometer Space Antenna (LISA). The gravitational waves generated during the QCD phase transition, however, are outside the LISA sensitivity bands.