Diluting quark flavor hierarchies using dihedral symmetry

Abstract

We present a D 4 flavored extension of the SM which provides an intuitive reasoning for the masses and mixing patterns in the quark sector. In our model, the Cabibbo mixing angle stems purely from the scalar sector dynamics. In fact, the orders of magnitude of the CKM matrix elements are readily obtained from the hierarchical nature of the vacuum expectation values. Moreover, we also show that the smallness of the off-Cabibbo elements in the CKM matrix is strongly connected to the heaviness of the third generation of quarks.

Fermion mass hierarchies and mixings in a $B-L$ model with $D_4\times Z_4\times Z_2$ symmetry

“…[13][14][15] and the references therein). Among the discrete symmetries, D 4 has attracted the attention since it provides a very predictive description of the observed patterns of lepton and quark masses and mixing angles [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29], however, most of these works solved only some of sub-problems of the flavour problem. Thus, it would be wishful to construct a D 4 flavor model that can overcome all mentioned sub-problems including the origin of the charged-lepton mass hierarchy, the small values of three quark mixing angles, the neutrino mixing pattern with 2 large and 1 small angles, the two neutrino mass squared splittings, and the fermion mass hierarchy problem.…”

“…Beside the differences between previous works with D 4 symmetry, there is another important difference comes from the fermion mass hierarchy problem which has not been mentioned or has not been achieved in Refs. [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] 1 .…”