We study soft-gluon radiation in top quark decay within the framework of perturbative fragmentation functions. We present results for the b-quark energy distribution, accounting for soft-gluon resummation to next-to-leading logarithmic accuracy in both the MS coefficient function and in the initial condition of the perturbative fragmentation function. The results show a remarkable improvement a...

Top quark pair production by (polarized) γγ collisions offers an interesting testing ground of the Standard Model and its extensions. In this Letter we present results for differential cross sections of top quark pair production and decay including QCD radiative corrections. We take into account the full dependence on the top quark spins. We give analytic and numerical results for single and do...

We present the extension of two general algorithms for the treatment of infrared singularities arising in electroweak corrections to decay processes at next-to-leading order: the dipole subtraction formalism and the one-cutoff slicing method. The former is extended to the case of decay kinematics which has not been considered in the literature so far. The latter is generalised to production and...

This paper summarizes a variety of recent results on heavy quark production and decay. Considerable progress has been made by CDF and DØ in measuring top quark production and decay properties. The top quark mass been measured with an uncertainty that is less than 3%, a relative precision that is better than has been achieved for other quarks. Measurements of the top production and decay propert...

We extend the picture of B-meson decay constants obtained in lattice QCD beyond those of the B, Bs and Bc to give the first full lattice QCD results for the B , B s and B c. We use improved nonrelativistic QCD for the valence b quark and the highly improved staggered quark (HISQ) action for the lighter quarks on gluon field configurations that include the effect of u=d, s and c quarks in the se...

In order to observe a signal of possible CP violation in top-quark couplings, we study top-quark production and decay under the conditions of the Tevatron upgrade. Transverse energy asymmetries sensitive to CP violation are defined. Applying the recently proposed optimal method, we calculate the statistical significance for the direct observation of CP violation in the production and subsequent...

Angular distribution of the secondary lepton in top-quark production followed by subsequent semi-leptonic decay is studied assuming general top-quark couplings. It is shown that the distribution does not depend on any possible anomalous tbW couplings and is determined only by the standard V −A decay vertex for any production mechanism if certain well-justified conditions are satisfied. PACS: 13...

Radiation of gluons gives rise to extra jets in top quark events that can lead to complications in event reconstruction and mass measurement. I review recent results for gluon radiation in top quark production and decay, and discuss their implications for top quark physics. 1 Tevatron The presence of extra jets in t ¯ t events can complicate attempts to reconstruct the mass of the top quark fro...

On the QCD corrections to the charged Higgs decay of a heavy quark. Using dimensional regularization for both infrared and ultraviolet divergences, we confirm that the QCD corrections to the decay width Γ(t → H + b) are equal to those to Γ(t → W + b) in the limit of a large t quark mass.

Angular distribution of the secondary lepton in top-quark production followed by subsequent semi-leptonic decay is studied assuming general top-quark couplings. It is shown that the distribution does not depend on any possible anomalous tbW couplings and is determined only by the standard V −A decay vertex for any production mechanism if certain well-justified conditions are satisfied. PACS: 13...