Quark masses and mixings in the RS1 model with a condensing 4th generation

TL;DR

This paper explores how a 5D Randall-Sundrum model with a condensing 4th quark generation can explain quark mass hierarchies and mixings, emphasizing the need for non-trivial bulk interactions and specific symmetries.

Contribution

It introduces a novel approach combining 5D warped geometry with a condensing 4th generation to address quark mass and mixing hierarchies, including symmetry considerations.

Findings

Realistic quark masses require non-trivial bulk interaction hierarchies.

Modified Fritzsch-like textures can fit quark data well.

Imposing global U(1) symmetries helps reproduce CKM mixings.

Abstract

We study the hierarchy of quark masses and mixings in a model based on a 5-dimensional spacetime with constant curvature of Randall-Sundrum type with two branes, where the Electroweak Symmetry Breaking is caused dynamically by the condensation of a 4th generation of quarks, due to underlying physics from the 5D bulk and the first KK gluons. We first study the hierarchy of quark masses and mixings that can be obtained from purely adjusting the profile localizations, finding that realistic masses are not reproduced unless non trivial hierarchies of underlying 4-fermion interactions from the bulk are included. Then we study global U(1) symmetries that can be imposed in order to obtain non-symmetric modified Fritzsch-like textures in the mass matrices that reproduce reasonably well quark masses and CKM mixings.