Related papers: Higgs Properties and Fourth Generation Leptons
We analyze the phenomenological implications of introducing vector-like leptons on the Higgs sector in the Higgs Triplet Model. We impose only a parity symmetry which disallows mixing between the new states and the ordinary leptons. If the…
Searches for Higgs boson at the LHC have excluded standard model (SM) Higgs boson mass in the range between 127 GeV to 600 GeV. With a fourth generation, the excluded range is wider. To close the windows between 114 GeV to 127 GeV, the mode…
We study the implications of light third generation sparticles on the production cross section and decay widths of a light CP-even Higgs boson. For simplicity, we consider scenarios in which only one of the sfermions from the third…
Quantum corrections generate a quadratically divergent mass term for the Higgs boson in the Standard Model. Thus, if the Higgs boson has a mass of order 100 GeV, it implies the presence of a cut-off of the theory around TeV scale, and some…
A search is conducted for a new beyond-the-Standard-Model boson using events where a Higgs boson with mass 125 GeV decays to four leptons ($\ell =$ $e$ or $\mu$). This decay is presumed to occur via an intermediate state which contains one…
We discuss an alternative version of the electroweak standard model, in which only the heavy t quark, not the light fermions, couples to the Higgs boson with a strength given by the standard model. The Higgs particle decays dominantly into…
A scenario is presented where the $s$, $c$, and $b$ quark fusion Higgs production cross sections are enhanced with respect to those of the Standard Model. In particular the $c$ quark fusion production is very important and can account for a…
If next generations of heavy quarks and leptons exist within the standard model (SM), they can manifest themselves in Higgs boson production at the Tevatron and the LHC, before being actually observed. This generation leads to an increase…
The properties of a Higgs boson candidate are measured in the H to ZZ to 4l decay channel, with l = e, mu, using data from pp collisions corresponding to an integrated luminosity of 5.1 inverse femtobarns at the center-of-mass energy of…
One of the cleanest signatures of a heavy Higgs boson in models with vectorlike leptons is $H\to e_4^\pm \ell^\mp \to h\ell^+\ell^-$ which, in two Higgs doublet model type-II, can even be the dominant decay mode of heavy Higgses. Among the…
Within the four generation Standard Model, the Higgs couplings to gluons and to photons deviate in a significant way from the predictions of the three generation Standard Model. As a consequence, large departures in several Higgs production…
In a fourth generation model with heavy quarks, the production cross section of the Higgs boson in the gluon-gluon fusion process is significantly increased due to additional quark loops. In a similar way, the partial decay width of the…
We propose a search for Higgs decays with as many as eight leptons in the final state. This signal can arise in a simple model with a hidden vector ($A_d$) that gets mass via a hidden scalar ($h_d$) vacuum expectation value. The 125 GeV…
This paper presents a search for Higgs bosons decaying to four leptons, either electrons or muons, via one or two light exotic gauge bosons $Z_d$, $H\to Z Z_d \to 4\ell$ or $H\to Z_d Z_d \to 4\ell$. The search was performed using $pp$…
We present a simple solution to the little hierarchy problem in the MSSM: a vector-like fourth generation. With O(1) Yukawa couplings for the new quarks, the Higgs mass can naturally be above 114 GeV. Unlike a chiral fourth generation, a…
We analyse the impact of LHC and Tevatron Higgs data on the viability of the Standard Model with a sequential fourth generation (SM4), assuming Dirac neutrinos and a Higgs mass of 125 GeV. To this end we perform a combined fit to the signal…
We study the effect of a potential fourth quark generation on the upper and lower Higgs boson mass bounds. This investigation is based on the numerical evaluation of a chirally invariant lattice Higgs-Yukawa model emulating the same…
We study the effect of a light charged Higgs appearing in supersymmetric models containing two Higgs doublets on the measurement of leptonic branching ratios of the W boson at LEP. We show that the $2.8 \sigma$ excess of the branching ratio…
The Higgs boson may decay predominantly into a hidden sector, producing lepton jets instead of the standard Higgs signatures. We propose a search strategy for such a signal at hadron colliders. A promising channel is the associated…
The search for the effects of heavy fermions in the extension of the Standard Model with a fourth generation is part of the experimental program of the Tevatron and LHC experiments. Besides being directly produced, these states affect…