SMASH model and atmospheric neutrino mass splitting

C.R Das,Timo Kärkkäinen,Katri Huitu

doi:10.1088/1742-6596/1390/1/012076

Abstract

Five fundamental problems - neutrino mass, baryogenesis, dark matter, inflation, strong CP problem - are solved at one stroke in a model, dubbed as “SM-A-S-H” (Standard Model-Axion-Seesaw-Higgs portal inflation) by Andreas Ringwald et. al. The Standard Model (SM) particle content is extended by three right-handed SM-singlet neutrinos Ni, a vector-like color triplet quark Q, a complex SM-singlet scalar field σ that stabilises the Higgs potential, all of them being charged under Peccei-Quinn (PQ) U (1) symmetry, the vacuum expectation value vσ ∼ 1011 GeV breaks the lepton number and the Peccei-Quinn symmetry simultaneously. We found that numerically SMASH model not only solves five fundamental problems but also the sixth problem “Vacuum Metastability” through the extended scalar sector and can predict approximately correct atmospheric neutrino mass splitting around 0.05 eV and the solar neutrino mass splitting around 0.009 eV.

Highlights

After the discovery of the Standard Model (SM) Higgs boson [1, 2, 3], every elementary particle of the SM has been confirmed to exist
Five fundamental problems - neutrino mass, baryogenesis, dark matter, inflation, strong CP problem - are solved at one stroke in a model, dubbed as “SM-A-S-H” (Standard Model-Axion-Seesaw-Higgs portal inflation) by Andreas Ringwald et al The Standard Model (SM) particle content is extended by three right-handed SM-singlet neutrinos Ni, a vector-like color triplet quark Q, a complex SM-singlet scalar field σ that stabilises the Higgs potential, all of them being charged under Peccei-Quinn (PQ) U (1) symmetry, the vacuum expectation value vσ ∼ 1011 GeV breaks the lepton number and the Peccei-Quinn symmetry simultaneously
We found that numerically SMASH model solves five fundamental problems and the sixth problem “Vacuum Metastability” through the extended scalar sector and can predict approximately correct atmospheric neutrino mass splitting around 0.05 eV and the solar neutrino mass splitting around 0.009 eV

Summary

Introduction

After the discovery of the Standard Model (SM) Higgs boson [1, 2, 3], every elementary particle of the SM has been confirmed to exist. Even though the last forty years have been a spectacular triumph for the SM, the mass of the Higgs boson (mh = 125.09 ± 0.32 GeV) poses a serious problem for the SM It is well-known that the SM Higgs potential is metastable [4], as the sign of the quartic coupling, λH turns negative at instability scale ΛIS ∼ 1011 GeV. The effective SM Higgs coupling gains a positive correction δ ≡ λ2Hσ/λσ at mσ, where λHσ is the Higgs doublet-singlet portal coupling and λσ is the quartic coupling of σ This threshold mechanism is embedded in a recent SMASH [7] theory, which utilizes it at λHσ ∼ −10−6 and λσ ∼ 10−10.

Methods

4.18 GeV g1