Running of Neutrino Parameters and the Higgs Self-Coupling in a Six-Dimensional UED Model

TL;DR

This paper studies how neutrino parameters and the Higgs self-coupling evolve with energy in a six-dimensional universal extra-dimensional model, deriving renormalization group equations and setting bounds based on vacuum stability.

Contribution

It derives the RG equations for a 6D UED model including neutrino and Higgs sectors, and establishes bounds on the cutoff scale using vacuum stability criteria.

Findings

Leptonic mixing angle θ12 shows significant running.

Running of θ13 and θ23 is negligible.

Cutoff scale is smaller compared to 5D models, making effects potentially detectable.

Abstract

We investigate a six-dimensional universal extra-dimensional model in the extension of an effective neutrino mass operator. We derive the \beta-functions and renormalization group equations for the Yukawa couplings, the Higgs self-coupling, and the effecive neutrino mass operator in this model. Especially, we focus on the renormalization group running of physical parameters such as the Higgs self-coupling and the leptonic mixing angles. The recent measurements of the Higgs boson mass by the ATLAS and CMS collaborations at the LHC as well as the current three-flavor global fits of neutrino oscillation data have been taken into account. We set a bound on the six-dimensional model, using the vacuum stability criterion, that allows five Kaluza-Klein modes only, which leads to a strong limit on the cutoff scale. Furthermore, we find that the leptonic mixing angle \theta_{12} shows the most sizable running, and that the running of the angles \theta_{13} and \theta_{23} are negligible. Finally, it turns out that the findings in this six-dimensional model are comparable with what is achieved in the corresponding five-dimensional model, but the cutoff scale is significantly smaller, which means that it could be detectable in a closer future.