Higgs Mass Bounds, Type II SeeSaw and LHC

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.

Vacuum stability, perturbativity, EWPD and Higgs-to-diphoton rate in type II seesaw models

“…Since we further take the region of |ξ| 10 −2 in our analysis, some of the effects with a largest possible value of ξ [8,16] can be safely neglected.…”

Type II seesaw and the PAMELA/ATIC signals

“…First, our model has important implications for the SM Higgs boson mass. As shown in [23], the SM Higgs boson mass bounds obtained from imposing vacuum stability and perturbativity of the quartic Higgs coupling can be dramatically altered in the presence of type II seesaw. In particular, the Higgs boson mass window with type II seesaw can encompass mass regions otherwise not allowed.…”

Renormalization Group Evolution of Neutrino Masses and Mixing in Seesaw Models

“…will alter the ρ-parameters from the SM prediction ρ ≈ 1, at tree level and hence will get a strong constraint from the current precision data [44].…”