Gravitational waves from the minimal gauged U(1)B-L model

An additional U(1) gauge interaction is one of the promising extensions of the standard model of particle physics. Among others, the U(1)(B-L) gauge symmetry is particularly interesting because it addresses the origin of Majorana masses of right-handed neutrinos, which naturally leads to tiny light neutrino masses through the seesaw mechanism. We show that, based on the minimal U(1)(B-L) model, the symmetry breaking of the extra U(1) gauge symmetry with its minimal Higgs sector in the early universe can exhibit the first-order phase transition and hence generate a large enough amplitude of stochastic gravitational wave radiation that is detectable in future experiments.