Related papers: Second Order QCD Corrections to the Top Decay Rate
We introduce an anomalous top quark coupling (right-handed current) into Standard Model Lagrangian. Based on this, a more complete calculation of $b \to s\gamma $ decay including leading log QCD corrections from $m_{top}$ to $M_W$ in…
The calculation of partial decay rates in B --> X_u l nu decays at next-to-next-to-leading order (NNLO) in alpha_s and to leading order in 1/m_b is described. New results for the hard function are combined with known results for the jet…
In this paper, the twist-3 two parton corrections in charmless $B\to PP$ decays are shown to be factorizable under the QCD factorization approach. The factorizability of the twist-3 two parton corrections is constructed on the following…
The next-to-next-to-leading order perturbative QCD corrections to R_tau and the higher moments of the invariant mass distribution in the hadronic tau decays are considered. The renormalization scheme dependence of these corrections is…
We present results from quenched lattice QCD for the form factors for the decay $B\to\rho l\nu$. The calculations are performed using a nonperturbatively improved action and operators at two values of the lattice spacing. The bottom quark…
We present a lattice QCD calculation of the $\rho$ meson decay width via the $P$-wave scattering phase shift for the I=1 two-pion system. Our calculation uses full QCD gauge configurations for $N_f=2$ flavors generated using a…
Triggered by the observation of four top-quark production at the LHC by the ATLAS and CMS collaboration we report on the calculation of the next-to-leading order QCD corrections to the Standard Model process $pp \to t\bar{t}t\bar{t}$ in the…
In this work, we study the exclusive decay of $\Upsilon$ into $J/\psi$ in association with $\eta_c$ ($\chi_{c0,1,2}$). The decay widths for different helicity configurations are evaluated up to QCD next-to-leading order within the…
A precise measurement of the top quark mass, a fundamental parameter of the Standard Model, is among the most important goals of top quark studies at the Large Hadron Collider. Apart from the standard methods, numerous new observables and…
In this proceedings we briefly report on the state-of-the-art NLO QCD computation for the $pp\to t\bar{t}\gamma$ process in the di-lepton channel. We describe higher-order corrections to the $e^+\nu_e \, \mu^- \bar{\nu}_\mu \,…
The leading-order electromagnetic and strong isospin-breaking corrections to the ratio of $K_{\mu 2}$ and $\pi_{\mu 2}$ decay rates are evaluated for the first time on the lattice, following a method recently proposed. The lattice results…
We present a complete $O(\alpha_s^2)$ correction to the differential width of the inclusive semileptonic decay $b\to cl\nu_l$ at the kinematical point of vanishing invariant mass of the leptons, $q^2=0$. Together with the recently computed…
The semi-inclusive decay processes of a top quark into a charged pseudo-scalar meson and a jet are studied within the framework of QCD factorization. The leading power of the decay matrix elements can be factorized into heavy-to-light quark…
The QCD-induced $W^\pm \gamma$ production channels in association with two jets are computed at next-to-leading order QCD accuracy. The W bosons decay leptonicly and full off-shell and finite width effects as well as spin correlations are…
Calculations of radiative corrections to the top quark width are reviewed. QCD effects are discussed for $t-\bar t$ systems produced in $e^+e^-$ annihilation near the energy threshold.}
We analyze the order alpha_s^2 corrections to the single inclusive jet cross section in lepton-nucleon deep inelastic scattering. The full calculation is done analytically, in the small cone approximation, obtaining finite NLO partonic…
We investigate the two-photon decay rate of a highly excited atomic state which can decay to bound states of lower energy via cascade processes. We show that a naive treatment of the process, based on the introduction of phenomenological…
We compute the complete imaginary part of the NRQCD Lagrangian at order 1/M^4 in the heavy-quark mass expansion, which includes center of mass operators, and at order alpha_s^2 in the matching coefficients. We also compute the imaginary…
We perform a lattice QCD calculation of the $\chi_{c0} \rightarrow 2\gamma$ decay width using a model-independent method which does not require a momentum extrapolation of the corresponding off-shell form factors. The simulation is…
A Higgs boson in the intermediate mass range is considered. An effective Lagrangian approach is used in order to evaluate the top-induced QCD corrections of order $\alpha_s^3$ to the decay into light quarks and $O(\alpha_s^4)$ corrections…