We compute the complete supersymmetric next-to-leading order corrections to the production of a light Higgs boson in weak boson fusion. The size of the electroweak corrections is of similar order as the next-to-leading order corrections in the Standard Model. The supersymmetric QCD corrections turn out to be significantly smaller than their electroweak counterparts. These higher--order corrections are an important ingredient to a precision analysis of the (supersymmetric) Higgs sector at the LHC, either as a known correction factor or as a contribution to the theory error.
We consider the supersymmetric extension of the Standard Model with neutrino Yukawa interactions and R-parity violation. We found that R-parity breaking term λνH_u H_d leads to an additional F-type contribution to the Higgs scalar potential, and thus to the masses of supersymmetric Higgs bosons. The most interesting consequence is the modification of the tree-level expression for the lightest neutral supersymmetric Higgs boson mass. It appears that due to this contribution the bound on the lightest Higgs mass may be shifted upwards, thus slightly opening the part of the model parameter space e…
The electroweak symmetry is nonlinearly realized in an extension of the minimal supersymmetric standard model (MSSM) through an additional pair of constrained Higgs doublet superfields. The superpotential couplings of this constrained Higgs doublet pair to the MSSM Higgs doublet pair catalyze their vacuum expectation values. The Higgs and Higgsino-gaugino mass spectrum is presented for several choices of supersymmetry (SUSY) breaking and Higgs superpotential mass parameters. The additional vacuum expectation values provided by the constrained fields can produce a phenomenology quite different …
We present a full calculation of the supersymmetric NLO corrections to Higgs boson production via vector-boson fusion. The supersymmetric QCD corrections turn out to be significantly smaller than the electroweak ones. These higher-order corrections are an important ingredient to a precision analysis of the Higgs sector at the LHC.
We show that the gauge singlet scalar boson in low-energy supersymmetric model may behave as the standard model (SM) Higgs boson if the singlet couples to (heavy) vector-like colored particles. In this case, the SM-Higgs-like signal at the LHC can be mimicked by the singlet production process for wide range of the singlet mass.
We study the mass, the mixing and the coupling with $Z$ boson of the lightest Higgs boson in the next-to-minimal supersymmetric standard model. The vacuum structure of the Higgs potential is analyzed and the new false vacua are discussed. The significant parameter region can be excluded by requiring that the realistic vacuum is deeper than false vacua, which result in constraints on the properties of the lightest Higgs boson.
The minimal supersymmetric standard model (MSSM) is extended by including an additional pair of constrained Higgs doublet superfields through which the electroweak symmetry is nonlinearly realized. The superpotential couplings of this constrained Higgs doublet pair to the MSSM Higgs doublet pair catalyze the later nontrivial vacuum expectation values. The mass spectrum of the Higgs scalars and Higgsino-gaugino sector is presented for several choices of supersymmetry (SUSY) breaking and Higgs superpotential mass parameters. The effect of the the additional constrained fields and multiple vacuum…
Although supersymmetry remains the best candidate for solving the electroweak hierarchy problem, a supersymmetric Higgs boson near 125 GeV requires heavy scalars, highly-mixed stops, or non-minimal contributions to the Higgs potential. Extensions of the Standard Model (SM) gauge group provide an attractive means of raising the Higgs mass through non-decoupling D-term contributions to the Higgs quartic, but in most cases this correction is correlated with an enhanced coupling to bottom quarks and tau leptons that is disfavored by current fits to LHC Higgs data. In this work we demonstrate that …
The problems of the standard model are briefly reviewed and the motivations for introducing supersymmetry are discussed. Two realistic supersymmetric models; the Minimal SuperSymmetric Model, MSSM, and its proposed extension NMSSM are introduced briefly and then some details of the Higgs sector of NMSSM are stated and some constraints on parameters are described. I then explore the Higgs boson masses and couplings for some interesting scenarios, including a few different ways of taking the limit where NMSSM reduces to MSSM.
We consider a Dirac singlet fermion as thermal dark matter for explaining the X-ray line in the context of a supersymmetric Higgs-portal model or a generalized Dirac NMSSM. The Dirac singlet fermion gets a mass splitting due to their Yukawa couplings to two Higgs doublets and their superpartners, Higgsinos, after electroweak symmetry breaking. We show that a correct relic density can be obtained from thermal freeze-out, due to the co-annihilation with Higgsinos for the same Yukawa couplings. We discuss the phenomenology of the Higgsinos in this model such as displaced vertices at the LHC.
Higgs at the Tevatron in Extended Supersymmetric Models
超对称模型加上一个额外的单重场,使得希格斯玻色子玻色子有可能衰变为两个赝标量,a。如果这些赝标量的质量高于b bbar阈值,a -> b bbar通常是主要的衰变模式。如果希格斯粒子的产生截面相对于标准模型的产生截面得到增强,则在Tevatron的背景之上可以看到衰变h -> a a -> b bbar b bbar。
We examine a possibility to explain the signals of dark matter direct detection from DAMA and CoGeNT experiments, under the framework of supersymmetric extension of the standard model. For this purpose, we introduce four Higgs doublet fields and assume that one pair of Higgs fields which have very small vacuum expectation values gives sizable effects for annihilation and scattering processes of dark matter. We show that the preferred parameter regions for DAMA and CoGeNT results can be simultaneously explained by supersymmetric four-Higgs doublet model with the parameters consistent with the o…
In supersymmetric standard models with multi Higgs doublet fields, selfcoupling constants in the Higgs potential come only from the D-terms at the tree level. We investigate the decoupling property of additional two heavier Higgs doublet fields in the supersymmetric standard model with four Higgs doublets. In particular, we study how they can modify the predictions on the quantities well predicted in the minimal supersymmetric standard model (MSSM), when the extra doublet fields are rather heavy to be measured at collider experiments. The B-term mixing between these extra heavy Higgs bosons an…
In the supersymmetric standard model which is not minimal, the Higgs potential does not conserve CP symmetry generally. Assuming that there exists an SU(2)-triplet Higgs field, we discuss resultant CP-violating effects on the Higgs bosons. The experimentally observed Higgs boson, which should be CP-even in the standard model, could decay into two photons of CP-odd polarization state non-negligibly. For the second lightest Higgs boson, in sizable region of parameter space, the dominant decay modes are different from those expected by the standard model. The two-photon decay could yield both eve…
The supersymmetric grand unified theory with the Hosotani mechanism predicts the existence of adjoint chiral supermultiplets at the SUSY breaking scale. In particular, the SU(2) triplet and the singlet chiral superfields affect the Higgs sector. We investigate the contributions from these adjoint chiral multiplets to the masses of the Higgs sector particles and their couplings to the standard model particles. We show that the predicted values of the Higgs sector parameters deviate from the standard model and the minimal supersymmetric standard model by O(1)% - O(10)%.