Related papers: Perturbative Heavy Quark Fragmentation Function th…
The decays of $D$ mesons to $K l \nu$ and $K^* l \nu$ final states exhibit significant deviations from the predictions of heavy-quark symmetry, as one might expect since the strange quark's mass is of the same order as the QCD scale.…
We develop perturbative QCD factorization theorem for the semileptonic heavy baryon decay $\Lambda_b \to \Lambda_c l\bar{\nu}$, whose form factors are expressed as the convolutions of hard $b$ quark decay amplitudes with universal…
We present a calculation of the perturbative quark-to-quark transverse parton distribution function at next-to-next-to-leading order based on a gauge invariant operator definition. We demonstrate for the first time that such a definition…
Fracture functions are parton distributions of an initial hadron in the presence of an almost collinear particle observed in the final state. They are important ingredients in QCD factorization for processes where a particle is produced…
There are presently two approaches to calculating heavy quark production for the deeply inelastic scattering process in current literature. The conventional fixed-flavor scheme focuses on the flavor creation mechanism and includes the heavy…
Within NRQCD factorization framework, in this work we compute, at the lowest order in velocity expansion, the next-to-leading-order (NLO) perturbative corrections to the short-distance coefficients associated with heavy quark fragmentation…
We present O(alpha_s^1) corrections to deep inelastic scattering amplitudes on massive quarks obtained within the scheme of Aivazis, Collins, Olness and Tung (ACOT). After identifying the correct subtraction term the convergence of these…
The production of heavy quarks at large $\pt$ ($\pt\gg m$) in hadronic collisions is considered. The analysis is carried out in the framework of perturbative fragmentation functions, thereby allowing a resummation at the NLO level of final…
We present a model calculation of leading order interference fragmentation functions arising from the distribution of two hadrons produced in the same jet of a fragmenting quark in a hard process. Using a simple spectator model for the…
Collisional fragmentation is a ubiquitous phenomenon arising in a variety of astrophysical systems, from asteroid belts to debris and protoplanetary disks. Numerical studies of fragmentation typically rely on discretizing the size…
Next-to-leading order parton fragmentation functions into light mesons are presented. They have been extracted from real and simulated $e^+e^-$ data and used to predict inclusive single particle distributions at different machines.
We discuss heavy quarkonium production through parton fragmentation, including a review of arguments for the factorization of high-p_T particles into fragmentation functions for hadronic initial states. We investigate the further…
The next-to-leading-order (NLO) cross section for the production of heavy quarks at large transverse momenta ($p_\perp$) in $\gamma\gamma$ collisions is calculated with perturbative fragmentation functions (PFF's). This approach allows for…
Spin dependent fragmentation functions for heavy flavor quarks to fragment into heavy baryons are calculated in a quark-diquark model. The production of intermediate spin 1/2 and 3/2 excited states is explicity included. The resulting…
In this paper we present the analytic form of the heavy-quark coefficient functions for deep-inelastic lepton-hadron scattering in the kinematical regime $Q^2 \gg m^2$ . Here $Q^2$ and $m^2$ stand for the masses squared of the virtual…
Analytic formulae are given for QCD corrections to the lepton spectra in decays of polarised up and down type heavy quarks. These formulae are much simpler than the published ones for the corrections to the spectra of charged leptons…
We compute the imaginary part of the heavy quark contribution to the photon polarization tensor, i.e. the quarkonium spectral function in the vector channel, at next-to-leading order in thermal QCD. Matching our result, which is valid…
We discuss the polarised fragmentation functions of quarks and gluons in Perturbative Quantum Chromodynamics. The Altarelli-Parisi evolution equations governing these fragmentation functions are presented. We find that the first moment of…
We present a systematic QCD analysis of the strange--charm and bottom--top contributions to transverse and longitudinal structure functions in charged--current deep inelastic scattering. Various ${\cal O}(\alpha_s^1)$ schemes are studied…
Quark fragmentation functions describe the hadronization process of a quark where any of the final-state hadrons carries a fraction of its initial momentum. We compute these fragmentation functions for a cascade that includes pions, kaons,…