we used qcd factorization for the hadronic matrix elements to show that the existing data, in particular the branching ratios br ( ?j/?k) and br ( ?j/??), can be accounted for this approach. we analyzed the decay within the framework of qcd factorization. we have complete calculation of the relevant hard-scattering kernels for twist-2 and twist-3. we calculated this decays in a special scale ( ...

using qcd factorization for the hadronic matrix elements, we show that existing data, inparticular the branching ratios br ( b →j/ψk) and br ( b →j/ψπ), can be accounted for in this approach.we analyze the decay b j /k( ) within the framework of qcd factorization. the calculation of therelevant hard-scattering kernels for twist-2 and twist-3 is completed. we calculate this decay in a special...

Diiraction is an old subject which has received much interest in recent years due to the advent of diiractive hard scattering. We discuss some theoretical models and experimental results that have shown new striking eeects, e.g. rapidity gaps in jet and W production and in deep inelastic scattering. Many aspects can be described through the exchange of a pomeron with a parton content, but the p...

Recent developments in the theory and experiment of QCD hard scattering are described. 1 Preamble: How Perturbative QCD Works This has been an active year for experimental results and theoretical developments in quantum chromodynamics. In this talk I will cover a selection of topics presented at this conference, tied together by the interplay of soft and hard physics. QCD is certainly the most ...

Diffraction is an old subject which has received much interest in recent years due to the advent of diffractive hard scattering. We discuss some theoretical models and experimental results that have shown new striking effects, e.g. rapidity gaps in jet and W production and in deep inelastic scattering. Many aspects can be described through the exchange of a pomeron with a parton content, but th...

We resum distributions that are singular at partonic threshold (the elastic limit) in heavy quark production, in terms of logarithmic behavior in moment space. The method may be applied to a variety of cross sections sensitive to the edge of phase space, including transverse momentum distributions. Beyond leading logarithm, dependence on the moment variable is controlled by a matrix renormaliza...