Do neutrinos dream in 5D? Towards a comprehensive extra-dimensional neutrino phenomenology

TL;DR

This paper explores how neutrino masses and mixing patterns are affected by five-dimensional bulk fermions in large extra dimension models, analyzing various mass generation scenarios and their experimental implications.

Contribution

It systematically investigates four scenarios of neutrino mass generation in 5D models, deriving phenomenological consequences and constraints from experimental data.

Findings

Different mass spectra and mixing patterns are derived for each scenario.

Constraints on extra-dimensional parameters are established based on neutrino oscillation data.

Abstract

This paper provides a comprehensive overview of neutrino masses and mixing in Large Extra Dimension scenarios, focusing on the phenomenological impact of a five-dimensional (5D) bulk fermion. In a flat extra dimension compactified on an $S^1/\mathbb{Z}_2$ orbifold, this fermion manifests as a Kaluza-Klein tower of right-handed neutrinos in the 4D effective theory. We systematically investigate four distinct scenarios for mass generation, considering both Dirac and Majorana mass terms originating from either the bulk or the 3-brane. For each case, we analyse the consequences for neutrino oscillations in a vacuum and in matter, deriving the resulting mass spectra and mixing patterns. By comparing these theoretical predictions with experimental data, we explore the constraints on the large extra dimensions' parameters.