相关论文: Vacuum Stability and Higgs Diphoton Decays in the …
The ATLAS and CMS collaborations discovered a new boson particle. If the new boson is the Higgs boson, the diphoton signal strength is 1.5 - 1.8 times larger than the Standard Model (SM) prediction, while the WW and ZZ signal strengths are…
The ATLAS and the CMS collaborations have presented results which show an excess of the Higgs to diphoton decay channel. In the Minimal Supersymmetric Standard Model (MSSM), this situation can be achieved by a light stau and a large…
Although recent Higgs data from ATLAS and CMS are compatible with a Standard Model (SM) signal at $2\sigma$ level, both experiments see indications for an excess in the diphoton decay channel, which points to new physics beyond the SM.…
Light, electrically charged vector-like `leptons' with order one Yukawa couplings can enhance the Higgs to diphoton decay rate, as is suggested by measurements of the signal strength \mu_{\gamma\gamma} by ATLAS and CMS. However, the large…
It is shown that substantially enhanced Higgs to diphoton rate induced by light staus with large left-right mixing in MSSM requires at the GUT scale non-universal gaugino masses with bino and/or wino lighter than gluino. The possibility of…
We study the di-photon rate in Higgs decays within singlet extensions of the supersymmetric standard model. In particular we point out that light charginos as well as a light charged Higgs can significantly contribute to the corresponding…
Motivated by the discovery hint of the Standard Model (SM) Higgs mass around 125 GeV at the LHC, we study the vacuum stability and perturbativity bounds on Higgs scalar of the SM extensions including neutrinos and dark matter (DM). Guided…
In the high-scale (split) MSSM, the measured Higgs mass sets an upper bound on the supersymmetric scalar mass scale MSUSY around $10^{11}$ ($10^{8}$) GeV, for $\tan\beta$ in the standard range and the central value of the top quark mass…
The parameters of the Higgs potential of the Minimal Supersymmetric Standard Model (MSSM) receive large radiative corrections which lift the mass of the lightest Higgs boson to the measured value of 126 GeV. Depending on the MSSM…
We discuss the impact on the stau masses of the additional D-terms in U(1)-extended MSSM models. We show, explicitly for the B-L-SSM, that these contributions can play a crucial role in the explanation of the enhanced diphoton decay rate of…
The measurements of the Higgs mass and top Yukawa coupling indicate that we live in a very special Universe, at the edge of the absolute stability of the electroweak vacuum. If fully stable, the Standard Model (SM) can be extended all the…
The ATLAS and CMS experiments have recently announced the discovery of a Higgs-like resonance with mass close to 125 GeV. Overall, the data is consistent with a Standard Model (SM)-like Higgs boson. Such a particle may arise in the minimal…
We study the implications of the LHC Higgs signals on the Higgs mixing in the next-to-minimal supersymmetric standard model (NMSSM). The Higgs couplings can depart from their values in the standard model (SM) due to mixing effects. However…
We analyze the vacuum stability in the inert Higgs doublet extension of the Standard Model (SM), augmented by right-handed neutrinos (RHNs) to explain neutrino masses at tree level by the seesaw mechanism. We make a comparative study of the…
In models with an extended Higgs sector, such as the (N)MSSM, scalar states mix with one another. Yet, the concept of Higgs mixing is problematic at the radiative level, since it introduces both a scheme and a gauge dependence. In…
The latest results of the ATLAS and CMS experiments point to a preferred narrow Higgs mass range (m_h \simeq 124 - 126 GeV) in which the effective potential of the Standard Model (SM) develops a vacuum instability at a scale 10^{9} -10^{11}…
We study a supersymmetric extension of the vector-like lepton scenario, such that the vacuum instability induced by large lepton Yukawa couplings is lifted by the presence of superpartners at or below the TeV scale. In order to preserve the…
We study the vacuum stability and unitarity conditions for a 125 GeV Standard Model (SM)-like Higgs boson mass in the type-II seesaw model. We find that, as long as the seesaw scale is introduced below the SM vacuum instability bound, there…
Motivated by recent results from Higgs searches at the Large Hadron Collider, we consider possibilities to enhance the diphoton decay width of the Higgs boson over the Standard Model expectation, without modifying either its production rate…
We show that supersymmetric "new physics" beyond the MSSM can naturally accommodate a Higgs mass near 126 GeV and enhance the signal rate in the Higgs to diphoton channel, while the signal rates in all the other Higgs decay channels…