Threshold Corrections to the MSSM Finite-Temperature Higgs Potential

Mikhail Dolgopolov,Elza Rykova,Mikhail Dubinin

doi:10.4236/jmp.2011.25039

Abstract

In the minimal supersymmetric standard model (MSSM) the one-loop finite-temperature corrections from the squark-Higgs bosons sector are calculated, the effective two-Higgs-doublet potential is reconstructed and possibilities of the electroweak phase transition in full MSSM ($m_{H^\pm}$, ${\tt tg}\beta$, $A_{t,b}$, $\mu$, $m_Q$, $m_U$, $m_D$) parameter space are studied. At large values of $A_{t,b}$ and $\mu$ of around 1 TeV, favored indirectly by LEP2 and Tevatron data, the threshold finite-temperature corrections from triangle and box diagrams with intermediate third generation squarks are very substantial. The four types of bifurcation sets are defined for the two-Higgs-doublet potential. High sensitivity of the low-temperature evolution to the effective two-doublet and the MSSM squark sector parameters is observed, but rather extensive regions of the full MSSM parameter space allow the first-order electroweak phase transition respecting the phenomenological constraints at zero temperature. As a rule, these regions of the MSSM parameter space are in line with the case of a light stop quark.

Highlights

The absence of antimatter in the Universe, a small ratio of the observed number of baryons to the observed number of photons nB n 6 10 10 and the absence of light CP-even Higgs boson signal at LEP2 and Tevatron energies lay a specific claim to models of particle physics
The baryon asymmetry and an extremely small nB n could be understood on the basis of Sakharov conditions, which are respected at the electroweak phase transition, expected to take place at the temperature of the order of 102 GeV
The situation becomes better in the minimal supersymmetric model (MSSM) where sparticles, extended two-doublet Higgs sector with the two background fields and nonstandard sources of CP-violation provide a number of new possibilities

Summary

Introduction

The absence of antimatter in the Universe (the baryon asymmetry), a small ratio of the observed number of baryons to the observed number of photons nB n 6 10 10 and the absence of light ( mH 100 GeV) CP-even Higgs boson signal at LEP2 and Tevatron energies lay a specific claim to models of particle physics. The situation becomes better in the minimal supersymmetric model (MSSM) where sparticles, extended two-doublet Higgs sector with the two background fields and nonstandard sources of CP-violation provide a number of new possibilities. In a number of approaches [3] the electroweak phase transition is defined by evolution of the finite temperature effective Higgs potential involving the cubic term in the background scalar fields v1, v2. The larger this term is, the stronger pronounced turns out to be the first order phase transition, which is essential for consistency with the Higgs boson mass beyond.

Finite Temperature Corrections of Squarks

A22mb2

T v4 cos2 2

Summary