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I present new results on the quark distribution in an on-shell heavy quark in perturbative QCD and explore its all–order relations with heavy–quark fragmentation. I first compute the momentum distribution function to all orders...

QCD inclusive B decay fragmentation heavy quarks renormalons Sudakov resummation.

The main challenge in computing inclusive cross sections and decay spectra in QCD is posed by kinematic thresholds. The threshold region is characterized by stringent phase–space constraints that are reflected in large...

I illustrate the role of infrared renormalons in computing inclusive B-decay spectra. I explain the relation between the leading ambiguity in the definition of Sudakov form factor exp(N /M) and that of the pole mass, and show...

I review the recent progress in computing inclusive B decay widths and spectra and its implications on the interpretation of measurements from the B factories. I discuss the inclusive charmless semileptonic decay, ¯B ! Xul¯ ...

The inclusive spectra of radiative and semi-leptonic B–meson decays near the endpoint is computed taking into account renormalons in the Sudakov exponent (Dressed Gluon Exponentiation). In this framework we demonstrate the...

inclusive B decay renormalons Heavy quark effective theory Factorization

Power corrections to exclusive processes are usually calculated using models for twist–four distribution amplitudes (DA) which are based on the leading–order terms in the conformal expansion. In this work we develop a different...

QCD Higher Twists Exclusive Processes renormalons

A main feature of high-energy scattering in QCD is saturation in the number density of gluons. This phenomenon is described by non-linear evolution equations, JIMWLK and BK, which have been derived at leading logarithmic...

We compute the differential ¯B → Xsγ decay width in the Standard Model as a function of the photon energy using Dressed Gluon Exponentiation (DGE). The resummed spectrum is matched with the fixed–order expansion, making use of...

inclusive B decay resummation renormalons heavy quarks

The main obstacle in describing inclusive decay spectra in QCD — which, in particular, limits the precision in extrapolating the measured ¯B −→ Xs rate to the full phase space as well as in extracting |Vub| from inclusive...

We review the progress in the QCD calculation of inclusive decay spectra. It was recently shown that the inherent infrared finiteness of inclusive spectra extends beyond the level of logarithms. Dressed Gluon...

We show that the ¯B −→ Xsγ photon energy (E ) spectrum can be reliably computed by resummed perturbation theory. Our calculation is based on Dressed Gluon Exponentiation (DGE) incorporating Sudakov and renormalon resummation. It...

inclusive B decay renormalons heavy quarks

We present a general all–order formulation of Sudakov resummation in QCD in terms of dispersion integrals. We show that the Sudakov exponent can be written as a dispersion integral over spectral density functions, weighted by...

The triple differential spectrum in ¯B −→ Xul¯ν is computed by Dressed Gluon Exponentiation (DGE). In this framework the on-shell calculation, converted into hadronic variables, can be directly used as an approximation to the...

inclusive B decay resummation renormalons heavy quarks

We compute the fully–differential ¯B → Xul¯ν decay width to all orders in perturbation theory in the large–β0 limit. Each of the five structure functions that build the hadronic tensor is expressed as a Borel integral, summing...

inclusive B decay resummation renormalons heavy quarks.

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board characteristics board size board composition board ownership financial performance Economy Corporate governance

The application of the Shannon entropy to study the relationship between information and structures has yielded insights into molecular and material systems. However, the difficulty in directly observing and manipulating atoms...