Leptonic Flavor Structure in the Brane Shifted Extra Dimensional Seesaw Mechanism

TL;DR

This paper explores a brane shifted extra dimensional seesaw model with a single bulk right-handed neutrino, analyzing its leptonic flavor structure and phenomenological signatures like lepton flavor violation without unitarity approximation.

Contribution

It introduces a novel analysis of leptonic flavor structure in a brane shifted extra dimensional seesaw model without unitarity approximation, enabling detailed phenomenological predictions.

Findings

Predicted ratios of lepton flavor violating decays correlated with neutrino mixing angles.

Branching ratios for μ→eγ close to experimental bounds with order-one Yukawa couplings.

Model provides testable signatures in lepton flavor violation experiments.

Abstract

We discuss the leptonic flavor structure generated by a brane shifted extra dimensional seesaw model with a single right handed neutrino in the bulk. In contrast to previous works, no unitarity approximation for the $3 \times 3$ submatrix has been employed. This allows to study phenomenological signatures such as lepton flavor violating decays. A strong prediction of the model, assuming CP conservation, are the ratios of flavor violating charged lepton decay and Z decay branching ratios which are correlated with the neutrino mixing angles and the neutrino mass hierarchy. Furthermore, it is possible to obtain branching ratios for $\mu \rightarrow e \gamma$ close to the experimental bounds even with Yukawa couplings of order one.