Related papers: The process `e+ e- --> H t t-bar' and its backgrou…
We have calculated the complete O(alpha) and O(alpha_s) radiative corrections to the Higgs-production process e+ e- -> t anti-t H in the Standard Model. This process is particularly interesting for the measurement of the top-quark Yukawa…
We calculate the cross section for e+e- --> H+ e- nubar in the two-Higgs-doublet model from one-loop diagrams involving top and bottom quarks. This process offers the possibility of producing the charged Higgs boson at the e+e- collider…
We estimate the accuracy with which the coefficient of the CP even dimension six operators involving Higgs and two vector bosons (HVV) can be measured at linear $e^+ e^-$ colliders. Using the optimal observables method for the kinematic…
We report a detailed simulation study of the search for $s$-channel Higgs boson production in $e^+e^-$ collisions at a center-of-mass (c.m.) energy of $\sqrt{s}=125\,\mathrm{GeV}$ at the CERN Future Circular Collider (FCC-ee), as a means to…
Understanding the mechanism of electroweak symmetry breaking and the origin of boson and fermion masses is among the most pressing questions raised in contemporary particle physics. If these issues involve one (several) Higgs boson(s), a…
In this study, Higgs production processes, Higgsstrahlung and vector boson (W and Z) fusion processes, were investigated for four different future lepton colliders (CEPC, ILC, CLIC, and FCC-ee). The cross sections for each production…
The complete matrix element for $e^+e^-\ar b\bar bW^+W^-$ has been computed at tree--level and applied to $Z^0H^0$ production followed by $Z^0\ar b\bar b$ and $H^0\ar W^+W^-$, keeping into account all irreducible backgrounds, which are…
The complete matrix element for $e^+e^-\ar W^+W^-\bar b b$ is computed at tree level and applied to: {\bf a)} $\bar t t$ production and decay ; {\bf b)} $ZH$ production followed by $Z\ar \bar bb$ and $H\ar WW$. In both cases we include…
We perform a detailed study of the process $e^+e^-\to \mu^+\mu^-\nu_l\bar\nu_l$ including all contributions. The contributions other than from real gauge boson production leads to a rich phenomenology. We explore the use of the process as a…
We perform a global effective-field-theory analysis to assess the combined precision on Higgs couplings, triple gauge-boson couplings, and top-quark couplings, at future circular $e^+e^-$ colliders, with a focus on runs below the $t\bar t$…
The complete matrix element for $e^+e^-\rightarrow b\bar b W^+W^-$ is computed at tree-level within the Minimal Supersymmetric Standard Model. Rates of interest to phenomenological analyses at the Next Linear Collider are given. In…
The production of the Higgs boson in association with a single top quark is sensitive to the relative sign of the coupling parameters describing its interaction with fermions and gauge bosons. The tHq production mode therefore provides an…
We present results for the lowest order cross sections, calculated with the complete set of the standard model Feynman diagrams, of all possible detection channels of the associated production of the top quark pair and the light Higgs…
The physics prospect at future linear $e^{+}e^{-}$ colliders for the study of the Higgs triple self-coupling via the process of $e^{+}e^{-}\to ZHH$ is investigated. In this paper, we calculate the contribution of the new particles predicted…
We calculate the contributions of the top-Higgs $h_{t}^{0}$ predicted by topcolor assisted technicolor(TC2) models to $e^{+}e^{-}\longrightarrow \overline{t}c\overline{\nu}_{e}\nu_{e}$ and compare the results with the contributions of…
We study consequences of CP violation in the $ht\bar{t}$ Yukawa coupling through the process $e^+e^- \to$ $h(125)t\bar{t}$. The helicity amplitudes are calculated in the $t\bar{t}$ rest frame, where the initial $e^+e^-$ current and the…
In this paper we investigate methods to study the $t\bar{t}$ Higgs coupling. The spin and CP properties of a Higgs boson are analysed in a model-independent way in its associated production with a $t\bar{t}$ pair in high-energy $e^+e^-$…
We perform a complete simulation of the process e^+ e^- --> b b-bar nu nu-bar, where nu can be an electron, muon or tau neutrino, in the context of a general Higgs coupling to b quarks. We parametrize the H b b-bar coupling as m_b/v (a + i…
In a previous paper, we studied the Higgs pair production in the standard model with the reaction $e^{+}e^{-}\to t \bar t HH$. Based on this, we study the Higgs pair production via $e^{+}e^{-}\to b \bar b HH$. We evaluate the total cross…
Electroweak symmetry breaking and the origin of mass of fermion and boson are fundamental questions to understand particle physics. The essential piece of this symmetry breaking, the Higgs boson, is the most probable particle to be…