Electroweak phase transition in a model with gauged lepton number
  In this work we study the electroweak phase transition in a model with gauged lepton number. Here, a family of vector-like leptons is required in order to cancel the gauge anomalies. Furthermore, these leptons can play an important role in the transition process. We find that this framework is able to provide a strong transition, but only for a very limited number of cases. 
Alfredo Aranda, Enrique Jim\'enez and Carlos A. Vaquera-Araujo
hep-ph