Related papers: Three Loop Top Quark Contributions to the rho Para…
We present numerical calculations of the partial width of the charged Higgs boson decay into a top quark, $H^- \rightarrow \bar{t} + b + X$, and the partial width of the top quark decay into a light charged Higgs boson $t \rightarrow H^+ +…
The top quark has a large Yukawa coupling with the Higgs boson. In the usual extensions of the standard model the Higgs sector includes extra scalars, which also tend to couple strongly with the top quark. Unlike the Higgs, these fields…
Carefully analyzing the dependence of the bounds on the Higgs-boson mass $\MH$ derived from the observables $\swbar^2(\LEP)$, $\swbar^2(\SLD)$, $\Gl$, $\MW$, $\GT$, $\Gh$, as well as $\Rb$ and $\Rc$, and considering the uncertainties in…
Using an effective potential approach, we compute two-loop radiative corrections to the MSSM lightest ${\cal CP}$-even Higgs boson mass $M_{h^0}$ to ${\cal O}(\alpha_t^2)$ for arbitrary left-right top-squark mixing and $\tan\beta$. We find…
We study the production of a Higgs boson in association with bottom quarks ($b\bar{b}H$) in hadronic collisions at the LHC, including the different contributions stemming from terms proportional to the top-quark Yukawa coupling ($y_t^2$),…
In the minimal supersymmetric model (MSSM), the upper limit of the lightest Higgs boson mass, $\mhl$, depends strongly on the top quark mass, $m_t$. We have computed the dominant two-loop radiative corrections to this upper limit of $\mhl$…
Including contributions of scale-dependent vacuum expectation values of Higgs scalars, we derive new one-loop formulas analytically for running quark-lepton masses at higher scales in MSSM. Apart from the gauge-coupling dependence being…
I briefly discuss some theoretical aspects of top mass measurements at the LHC. In particular, I illustrate a recent theoretical study performed using next-to-leading order (NLO) calculations interfaced to shower generators (NLO+PS) of…
We present a next-to-leading order calculation of H+jet in gluon fusion including the effect of a finite top quark mass $m_t$ at large transverse momenta. Using the recently published two-loop amplitudes in the high energy expansion and our…
We calculate the $gg\to\gamma\gamma$ amplitude by including the $t\bar t$ bound-state effects near their mass threshold. In terms of the non-relativistic expansion of the amplitude, the LO contribution is an energy-independent term in the…
The cross section for the reaction $e^+e^- \to t\bar{t} H$ depends sensitively on the top quark Yukwawa coupling $\lambda_t$. We calculate the rate for $t\bar{t}H$ production, followed by the decay $H\to b\bar{b}$, for a Standard Model…
The complete NNLO QCD corrections to the total cross section $\sigma(e^+e^- \to Z*,\gamma*\to t\bar t)$ in the kinematic region close to the top-antitop threshold are calculated by solving the corresponding Schroedinger equations exactly in…
If the quadratic divergence of the standard electroweak model and its local variation with mass scale are both assumed to be zero, then a modified one-loop calculation yields m_t = 117 GeV and m_H = 183 GeV. Such a scenario may be the…
We calculate the large top quark mass expansions for the H -> bb_bar decay rate in the order (alpha_s)^2 and for the H -> gluons decay rate in the order (alpha_s)^3. The obtained expansions rapidly converge in the region of their validity,…
The Top Yukawa coupling profoundly influences several core mysteries linked to the electroweak scale and the Higgs boson. We study the feasibility of measuring the Top Yukawa coupling at high-energy muon colliders by examining the…
We show how a measurement of the process pp-->t tbar H + X at the LHC and a measurement of the Higgs boson branching ratios BR(H-->b bar) and BR(H-->W+W-) at a future linear electron positron collider can be combined to extract a…
Results for the leading two-loop corrections of $\mathcal{O}{\left(\alpha_t^2\right)}$ from the Yukawa sector to the Higgs-boson masses of the MSSM with complex parameters are presented. The corresponding self-energies and their…
The strength of the Yukawa coupling of the leptons and quarks with the Higgs boson is uniquely determined by the Higgs mechanism for generating masses in the Standard Model. The top-Higgs coupling can be measured directly in the process…
We discuss the one-loop quantum corrections to the top quark width and to the hadronic widths of the Higgs bosons of the MSSM, and emphasize the results obtained in particular regions of the MSSM parameter space which have been proposed to…
We derive the first four terms of an expansion in mH^2/mtop^2 of the total Higgs cross-section through gluon fusion. At NLO we demonstrate the excellent convergence of this series to the known result keeping the exact top mass dependence.…