相关论文: Current Algebra Approach to Heavy Top Effects in $…
We present O(alpha_s^2) corrections to the decay t-->bW in the limit of a very large top quark mass, m_t >> m_W. We find that the O(alpha_s^2) effects decrease the top quark decay width Gamma_t by about 2%: Gamma_t =…
The partial decay rate $\Gamma(Z\to b\bar{b})$ is significantly influenced by the mass of the top quark due to electroweak radiative corrections. The leading $\sim m_t^2$ and the next-to-leading contribution $\sim \ln m_t^2$ are known to be…
QCD corrections to the electroweak one-loop result for the partial width $\Gamma(H\rightarrow b\bar{b})$ are studied. For the decay channel into bottom quarks the rate is affected by a virtual top quark through electroweak interactions. The…
Corrections of $O(\alpha_s^2)$ to the decay of the top quark into a W boson and a bottom quark are calculated. The method is based on an expansion of the top quark propagator for small external momentum, q, as compared to the top quark…
The leading heavy-top two-loop corrections to the \Zbb~vertex are determined from a direct evaluation of the corresponding Feynman diagrams in the large \Mt~limit. %The calculation is done in the naive %dimensional regularization scheme…
We calculate the ${\cal O}(\alpha_s^2 \beta_0 )$ corrections to the decay rate $b\rightarrow c\bar c s$. For reasonable values of $m_c/m_b$ this term is of the same order as both the one-loop and $\CO(\alpha_s^2 \log^2 m_W/m_b)$ corrections…
We calculate the b-dependent self-energy of the top quark at O(g^2 \alpha_s) by using a general massive two-loop algorithm proposed in a previous article. From this we derive by unitarity the O(\alpha_s) radiative corrections to the decay…
The $O(G^2_\mu m_t^4)$ correction to the $\rho$ parameter is computed within the Standard Model using the current algebra formulation of radiative corrections. This approach is proved to be equivalent to the effective Lagrangian method…
We review recent theoretical progress in the computation of radiative corrections beyond one loop within the standard model of electroweak interactions, both in the gauge and Higgs sectors. In the gauge sector, we discuss universal…
The O(alpha^2 mt^2/mw^2) correction to the relation between G_\mu and the vector boson masses is computed in the MSbar scheme, and the results are used to investigate the magnitude of the effect on the theoretical prediction of mw and…
We consider in detail various theoretical uncertainties of the perturbative predictions for the decay width of $H^0\rightarrow b\overline{b}$ process in the region $50\ GeV< M_H\leq 2M_W$. We calculate the order…
We calculate the top-quark-induced three-loop corrections of O(alpha_s^2 G_F M_t^2) to the Yukawa couplings of the first five quark flavours in the framework of the minimal standard model with an intermediate-mass Higgs boson, with mass M_H…
We present an analytic formula for the $O(\alpha_s)$ corrections to the decay $t\to H^+b$ for nonzero $m_H$ and $m_b$. The Equivalence Theorem is used to relate these corrections to those for the process $t\to W^+b$. Contrary to previously…
We compute the two-loop corrections of O(alpha_s^2) to the Yukawa couplings in the framework of the Minimal Supersymmetric Standard Model (MSSM). The calculation is performed using the effective Lagrangian approach under the approximation…
The partial decay rate of the $Z$ boson into bottom quarks constitutes an important decay channel. This is mainly due to the virtual presence of the top quark in the loop diagrams giving rise to correction factors which are quadratic in the…
We investigate the effect of one-loop corrections of ${\cal O}(\alpha_S^2\alpha_W)$ on the $t\bar t$ invariant mass spectrum at the Large Hadron Collider (LHC) in presence of both resonant and non-resonant Higgs boson effects. We show that…
We present the two-loop ${\cal O}(\alpha_sG_Fm_t^2)$ correction to the $b\bar b$ decay rate of the Stan\-dard-Model Higgs boson, assuming that the $t$ quark is much heavier than the Higgs boson. Apart from the universal correction connected…
We present for the first time the complete three-loop mixed electroweak-QCD ($\mathcal{O}(\alpha\alpha_s)$) corrections for the decay channel $H \to \gamma\gamma$, by implementing three different on-shell $\alpha$ schemes in computing the…
We review recent theoretical progress in the computation of radiative corrections beyond one loop within the standard model of electroweak interactions, both in the gauge and Higgs sectors. In the gauge sector, we discuss universal…
The $O(\alpha_{s})$ corrections to the cross section for $b \bar b \to W^{\pm}H^{\mp}$ at the LHC are calculated in the minimal supersymmetric standard model (MSSM) in the $\bar{MS}$ and OS (on-mass-shell) renormalization schemes. The…