相关论文: Light Dark Matter, Light Higgs and the Electroweak…
We consider, in the context of the minimal supersymmetric standard model, the case where the gravitino weighs 10^6 GeV or more, which is preferred by various cosmological difficulties associated with unstable gravitinos. Despite the large…
In this article, we examine the Standard Model extended with a $Y=0$ Higgs triplet and a real singlet. We consider the Higgs triplet to be odd under the $Z_2$ symmetry, and hence the lightest stable particle from the inert triplet becomes…
We consider a model where two new scalars are introduced in the standard model, assuming classical scale invariance. In this model the scale invariance is broken by quantum corrections and one of the new scalars acquires non-zero vacuum…
We study a two Higgs doublet model augmented by a scalar dark matter particle that provides an excellent fit to the LHC Higgs data and the Fermi-LAT 135 GeV line. The heavy CP-even Higgs boson, which predominantly mediates annihilation and…
The nature of the electroweak phase transition in two-Higgs-doublet models is revisited in light of the recent LHC results. A scan over an extensive region of their parameter space is performed, showing that a strongly first-order phase…
In the standard model, the weak gauge bosons and fermions obtain mass after spontaneous electro-weak symmetry breaking, which is realized through one fundamental scalar field, namely Higgs field. In this paper we study the simplest scalar…
Electroweak Baryogenesis is a particularly attractive theoretical scenario, since it relies on physics which can be tested at present high energy collider facilities. Within the Standard Model, it has been shown that the requirement of…
In the simplest Higgs-portal scalar dark matter model, the dark matter mass has been restricted to be either near the resonant mass ($m_h/2$) or in a large-mass region by the direct detection at LHC Run 1 and LUX. While the large-mass…
We study the electroweak phase transition by lattice simulations of an effective 3-dimensional theory, for a Higgs mass of about $35 GeV$. In the broken symmetry phase our results on masses and the Higgs condensate are consistent with…
We consider a simple extension of the Standard Model by the addition of N real scalar gauge singlets $\vp$ that are candidates for Dark Matter. By collecting theoretical and experimental constraints we determine the space of allowed…
We explore a novel possibility that dark matter has a light mass below 1GeV in a lepton portal dark matter model. There are Yukawa couplings involving dark matter, left-handed leptons and an extra scalar doublet in the model. In the light…
The allowed standard model Higgs mass range has been reduced to a region between 114 and 130 GeV or above 500 GeV, at the 99% confidence level, since the Large Hadron Collider (LHC) program started. Furthermore some of the experiments at…
We present an up-to-date analysis of the constraints imposed bythe precision data on the ($CP-$ conserving) Two-Higgs-Doublet Model of type II, with emphasis on the possible existence of very light neutral (pseudo)scalar Higgs boson with…
We perform a detailed study of an effective field theory which includes the Standard Model particle content extended by a pair of Weyl fermionic SU(2)-doublets with opposite hypercharges. A discrete symmetry guarantees that a linear…
It was recently argued by Hooper and Goodenough [arXiv:1010.2752] that the excess gamma ray emission from within 1-2 degrees of the galactic center can be well-described by annihilation of ~8 GeV dark matter particles into tau pairs. I show…
Weakly interacting massive particles provide a well-motivated framework for dark matter, naturally reproducing the observed relic abundance through thermal freeze-out. A recent claim of an indirect-detection signal from the Galactic halo,…
We study the dynamics of electroweak symmetry-breaking in an extension of the Standard Model where the Higgs sector is augmented by the addition of a real (Y = 0) isospin triplet. We show that this scenario exhibits a novel, two-step…
If fermion condensation is a main source of electroweak symmetry breaking, an ultra-heavy Higgs doublet of mass ~10^8 GeV can yield naturally small Dirac neutrino masses. We show that such a scenario can lead to a new leptogenesis mechanism…
The electroweak phase transition can be made first order by extending the Standard Model (SM) Higgs sector with extra scalars. The same new physics can explain the matter-antimatter asymmetry of the universe by supplying an extra source of…
After the discovery of a SM-like scalar state with mass of 125 GeV in 2012, the electroweak sector demands to be studied with all possible theoretical and experimental efforts. In this work we present a symmetric two Higgs doublet model…