Abstract:

We discuss spectra of gravitational waves which are originated by the strongly first order phase transition at the electroweak symmetry breaking, which is required for a successful scenario of electroweak baryogengesis.

Such spectra are numerically evaluated in a set of extended scalar sectors with additional N isospin-singlet fields as a concrete example of renormalizable theories.

We show the produced gravitational waves can be significant, so that they are  detectable at future gravitational wave interferometers. Furthermore, we conclude that future detailed observation of gravitational waves can be generally useful as a probe of extended scalar sectors with the first order phase transition.