Related papers: D-wave heavy quarkonium production in fixed target…
Coherent photoproduction of heavy quarkonia on nuclear targets is studied within the QCD color dipole formalism including several main phenomena: i) The correlation between impact parameter of a collision $\vec b$ and dipole orientation…
Based on the potential nonrelativistic QCD formalism, we compute the nonrelativistic QCD long-distance matrix elements (LDMEs) for inclusive production of $S$-wave heavy quarkonia. This greatly reduces the number of nonperturbative unknowns…
We present an implementation of heavy quarkonium production within a perturbative QCD cascade based on the Colour Dipole Cascade model. We consider the processes most relevant in the context of the psi' surplus at the Tevatron; g -> psi'…
We study leptoproduction of $J/\psi$ at large $Q^2$ within the nonrelativistic QCD (NRQCD) factorization formalism. The cross section is dominated by color-octet terms that are of order $\alpha_s$. The color-singlet term, which is of order…
We discuss the power scaling rules along the lines of a complete Heavy Quark Effective Field Theory (HQEFT) for the description of heavy quarkonium production through a color-octet mechanism. To this end, we firstly derive a tree-level…
A rigorous QCD analysis of the inclusive annihilation decay rates of heavy quarkonium states is presented. The effective-field-theory framework of nonrelativistic QCD is used to separate the short-distance scale of annihilation, which is…
Within the nonrelativistic quantum chromodynamics framework, we make a comprehensive study on the exclusive production of excited charmonium and bottomonium in $e^+e^-\to \gamma^*/Z^0 \to|(Q\bar{Q})[n]\rangle +\gamma$ ($Q=c$ or $b$ quarks)…
I present an introduction to the NRQCD factorization method for calculating annihilation rates and inclusive production rates for heavy quarkonium. Using this method, annihilation decay rates and sufficiently inclusive cross sections are…
Some examples of the most recent applications of the NRQCD factorization approach to quarkonium phenomenology are presented. In the first part of the talk the NLO calculations for $\chicj$ and $\Upsilon$ decays rates are compared to the…
I review the NRQCD factorization approach for quarkonium production and compare its predictions with measurements in hadron-hadron and ep collisions.
We test the nonrelativistic QCD factorization conjecture for inclusive quarkonium production at two loops by carrying out a covariant calculation of the nonrelativistic quantum chromodynamics (NRQCD) long-distance matrix element (LDME) for…
The conventional color-singlet model was challenged by the recent data on quarkonium production. Discrepancies in production rates were observed at the Tevatron, at LEP, and in fixed-target experiments. The newly advocated color-octet…
In this contribution we study the photoproduction of quarkonium in coherent proton-proton and nucleus-nucleus interactions at the LHC. The integrated cross sections and rapidity distributions are estimated using the Color Glass Condensate…
We investigate light dark matter production associated with a heavy quarkonium at B factories in a model-independent way by adopting the effective field theory approach for the interaction of dark matter with standard model particles. We…
We re-analyze Tavatron data on charmonium hadroproduction in the framework of the color-octet model implemented in the event generator PYTHIA taking into account initial-state radiation of gluons and Altarelli-Parisi evolution of…
We compute the color-singlet and color-octet nonrelativistic QCD (NRQCD) long-distance matrix elements for inclusive production of $P$-wave quarkonia in the framework of potential NRQCD. In this way, the color-octet NRQCD long-distance…
We revisit the problem of quark production in high energy heavy ion collisions, at leading order in $\alpha_s$ in the color glass condensate framework. In this first paper, we setup the formalism and express the quark spectrum in terms of a…
In the limit of heavy quark mass, the production cross section and polarization of quarkonia can be calculated in perturbative QCD. We study the $p_\perp$-averaged production of charmonium states in $\pi N$ collisions at fixed target…
We present a calculation for the photoproduction of $\eta_c$ under the framework of NRQCD factorization formalism. We find a quite unique feature that the color-singlet contribution to this process vanishes at not only the leading order but…
We discuss the various mechanisms potentially at work in hadroproduction of heavy quarkonia in the light of computations of higher-order QCD corrections both in the Colour-Singlet (CS) and Colour-Octet (CO) channels and the inclusion of the…