Undemocratic Dirac seesaw

Undemocratic Dirac seesaw

Blog Article

The standard model left-handed neutrinos and several right-handed neutrinos wiha 77891 can obtain a tiny Dirac mass matrix through their mixings with relatively heavy Dirac fermions.In this Dirac seesaw scenario, the mixings involving the left-handed neutrinos can be allowed much larger than those involving the right-handed neutrinos.This undemocratic parameter choice is attractive to phenomenology.We show that the small mixings between the heavy Dirac fermions and the right-handed neutrinos can have a common origin with the observed baryon asymmetry in the universe.

We also connect the introduction of right-handed neutrinos to the existence and stability of dark matter by a new U(1) gauge symmetry for dark photon or baryon-minus-lepton number.We then specify how to embed our scenario into a left-right symmetric theory farmhouse magnolia wreath or a grand unification theory.