Time Evolution of Lepton Number Carried by Majorana Neutrinos

We revisit the time evolution of the lepton family number for a SU(2) doublet consisting of a neutrino and a charged lepton. The lepton family number is defined through the weak basis of the SU(2) doublet, where the charged lepton mass matrix is real and diagonal. The lepton family number carried by the neutrino is defined by the left-handed current of the neutrino family. For this work we assume the neutrinos have Majorana mass. This Majorana mass term is switched on at time t = 0 and the lepton family number is evolved. Since the operator in the avor eigenstate is continuously connected to that of the mass eigenstate, the creation and annihilation operators for the two eigenstates are related to each other. We compute the time evolution of all lepton family numbers by choosing a specific initial avor eigenstate for a neutrino. The evolution is studied for relativistic and nonrelativistic neutrinos. The nonrelativistic region is of particular interest for the Cosmic Neutrino Background predicted from big bang models. In that region we find the lepton family numbers are sensitive to Majorana and Dirac phases, the absolute mass, and mass hierarchy of neutrinos.

Lepton number violation in a unified framework

We study the time evolution of lepton family number for a neutrino that forms an SU(2) doublet with a charged lepton. The lepton family number is defined through a weak basis of the SU(2) doublet in which the charged lepton mass matrix is a real and diagonal one. The lepton family number carried by the neutrino is defined with a left-handed current of the neutrino family. We study the time evolution of the lepton family number operator for the Majorana neutrino. To be definite, we introduce the mass term at $t=0$ and study the time evolution of the lepton family number for the later time. Since the operator in the flavor eigenstate is continuously connected to that of the mass eigenstate, the creation and annihilation operators for the flavor eigenstates are related to those of the mass eigenstates. The total lepton number of the Majorana neutrino is conserved. By choosing a specific flavor eigenstate of the neutrino as an initial state, we compute the time evolution of all lepton family numbers. They are sensitive to Majorana and Dirac phases and are also sensitive to the absolute mass and mass hierarchy of neutrinos.

The Hidden Flavors Solution to Solar Neutrino Problem

The Solar Neutrino Problem has been solved, maybe, but still, it is a confusing problem with an undefined solution. I think and We all could think that the mass of the neutrino, its flavor, and the solar problem is connected. In this paper, I have introduced hidden flavors of neutrino and predicted flavors to the whole lepton family with the help of the Solar Neutrino Problem. Hidden flavors are a theoretical prediction to the current solution of the Solar Neutrino Problem. And a lot of reviews are done for the current mechanism and dynamics of the neutrino system.

Non-Standard neutrino interactions and neutral gauge bosons

We investigate Non-Standard Neutrino Interactions (NSI) arising from a flavor-sensitive Z'Z′ boson of a new U(1)'U(1)′ symmetry. We compare the limits from neutrino oscillations, coherent elastic neutrino–nucleus scattering, and Z'Z′ searches at different beam and collider experiments for a variety of straightforward anomaly-free U(1)'U(1)′ models generated by linear combinations of B-LB−L and lepton-family-number differences L_\alpha-L_\betaLα−Lβ. Depending on the flavor structure of those models it is easily possible to avoid NSI signals in long-baseline neutrino oscillation experiments or change the relative importance of the various experimental searches. We also point out that kinetic ZZ–Z'Z′ mixing gives vanishing NSI in long-baseline experiments if a direct coupling between the U(1)'U(1)′ gauge boson and matter is absent. In contrast, ZZ–Z'Z′ mass mixing generates such NSI, which in turn means that there is a Higgs multiplet charged under both the Standard Model and the new U(1)'U(1)′ symmetry.

Onset of Magnetic Monopole-Antimonopole Condensation

We determine the critical strength of the effective electric coupling for the onset of Bose condensation of stable magnetic monopoles and antimonopoles in SU(2) Yang-Mills thermodynamics. Two scenarios are considered: infinitely fast and infinitely slow downward approaches of the critical temperature. Our results support the claim that the first lepton family and the weak interactions emerge from pure SU(2) gauge dynamics of scale MeV.