Probing Majorana Phases and Neutrino Mass Spectrum in the Higgs Triplet Model at the LHC

TL;DR

This paper explores how measurements of doubly charged Higgs boson decays at the LHC can reveal details about neutrino masses and Majorana phases, providing a way to test the Higgs Triplet Model.

Contribution

It demonstrates that precise LHC measurements of Higgs decay branching ratios can determine neutrino mass spectrum and Majorana CP violation phases.

Findings

Branching ratios depend on neutrino mass and Majorana phases.

Measurements of ee, emu, mumu channels can reveal neutrino mass hierarchy.

Potential to detect CP violation from Majorana phases.

Abstract

Doubly charged Higgs bosons (H^++) are a distinctive signature of the Higgs Triplet Model of neutrino mass generation. If H^++ is relatively light (m_{H^++} < 400GeV) it will be produced copiously at the LHC, which could enable precise measurements of the branching ratios of the decay channels H^++ to l_i l_j. Such branching ratios are determined solely by the neutrino mass matrix which allows the model to be tested at the LHC. We quantify the dependence of the leptonic branching ratios on the absolute neutrino mass and Majorana phases, and present the permitted values for the channels ee, emu and mumu. It is shown that precise measurements of these three branching ratios are sufficient to extract information on the neutrino mass spectrum and probe the presence of CP violation from Majorana phases.