Higgs Mass Bounds, Type II SeeSaw and LHC

TL;DR

This paper explores how the type II seesaw mechanism, involving scalar triplets, influences Higgs mass bounds and predicts new particles potentially detectable at the LHC.

Contribution

It analyzes the impact of scalar triplet couplings on Higgs mass bounds and identifies parameter regions allowing a lighter Higgs consistent with experimental limits.

Findings

Higgs mass bounds can be as low as 114.4 GeV within certain parameter regions.

Scalar triplet particles, including doubly charged scalars, could be within LHC detection range.

The model provides new insights into neutrino mass generation and Higgs phenomenology.

Abstract

In type II seesaw utilized to explain the observed neutrino masses and mixings, one extends the Standard Model (SM) by introducing scalar fields which transform as a triplet under the electroweak gauge symmetry. New scalar couplings involving the Higgs doublet then appear and, as we show, these have important implications for the Higgs boson mass bounds obtained using vacuum stability and perturbativity arguments. We identify, in particular, regions of the parameter space which permit the SM Higgs boson to be as light as 114.4 GeV, the LEP2 bound. The triplet scalars include doubly charged particles whose masses could, in principle, be in the few hundred GeV range, and so they may be accessible at the LHC.