Related papers: J/psi Spin Asymmetries in the Colour-Octet Model
We study the Sivers asymmetry in inelastic $J/\psi$ leptoproduction, $ep^\uparrow \to e+ J/\psi+X$, within a transverse momentum dependent scheme, the so-called generalized parton model (GPM). The effects of final-state interactions are…
Within the framework of transverse momentum dependent factorization in combination with nonrelativistic QCD, we study charmonium and bottomonium production in hadronic collisions. We focus on quarkonium states with even charge conjugation,…
The data for the production of the $\psi'$ meson in pA collisions at 450 GeV at CERN-SPS (of the NA50-collaboration) yields $\sigma(\psi' N)\approx 8$ mb under the assumption that the $\psi'$ is produced as a result of the space-time…
Theoretical analyses of the results on quarkonium production at large transverse momentum ($p_T$) in $p\bar p$ collisions, at the Tevatron have revealed two novel features of the physics of quarkonium production : 1) the contribution of…
The comparison of $J/\psi$ photoproduction data in the inelastic region with theoretical predictions based on the NRQCD approach has remained somewhat ambiguous and controversial, in particular at large values of the inelasticity variable…
The production mechanisms of charmonium states in both hadronic and heavy-ion collisions hold great significance for investigating the hot and dense QCD matter. Studying charmonium polarization in ultra-relativistic collisions can also…
A factorization theorem for $P$-wave quarkonium production, recently derived by Bodwin, Braaten, Yuan and Lepage, is applied to $\Upsilon \to \chi_{cJ} + X$, where $\chi_{cJ}$ labels the ${}^3 P_J$ charmonium states. The widths for…
We calculate the centrality dependence for coherent photoproduction of very low-$p_{T}$ $J/\psi$ at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) energies within the impact parameter dependent saturated color dipole…
We evaluate the production cross section for direct J/Psi and Upsilon integrated in P_T for various collision energies in the QCD-based Colour-Singlet Model (CSM). We consider the LO contribution from gluon fusion whose P_T-integrated cross…
Charmonium production and suppression in heavy-ion collisions at relativistic energies is investigated within different models, i.e. the comover absorption model, the threshold suppression model, the statistical coalescence model and the…
The associate $J/\psi+\gamma$ production at the LHC is studied completely at next-to-leading-order (NLO) within the framework of nonrelativistic QCD. By using three sets of color-octet long-distance matrix elements (LDMEs) obtained in…
Within the framework of a simple model, we study single-spin asymmetries for pion production in hadron-hadron collisions at high-energies with one hadron polarised. The asymmetries are generated via a mechanism of final (initial) state…
A comprehensive set of azimuthal single-spin and double-spin asymmetries in semi-inclusive leptoproduction of pions, charged kaons, protons, and antiprotons from transversely polarized protons is presented. These asymmetries include the…
We present a rigorous next-to-leading order analysis of J/psi yield and polarization within the factorization theorem of nonrelativistic QCD (NRQCD). To the orders considered, this framework depends on three free parameters, the color-octet…
We present the results of our analysis on charmonia ($J/\psi$ and $\psi'$) hadroproduction taking into account higher-order QCD effects induced by initial-state radiation in a Monte Carlo framework, with the colour-octet mechanism…
We present a detailed phenomenological study of $J/\psi$ polarization in semi-inclusive deep inelastic scattering processes, focusing on the kinematics accessible at the future Electron-Ion Collider. We show theoretical estimates for the…
We present a complete evaluation for $\jpsi(\psip)$ prompt production at the Tevatron and LHC at next-to-leading order in nonrelativistic QCD, including color-singlet, color-octet, and higher charmonia feeddown contributions. The…
Color-octet contributions to the associate $J/\psi+\gamma$ production are found to be negligible, compared to the ordinary color-singlet contribution. Within the color-singlet model the $J/\psi+\gamma$ production in the leading order is…
We study contributions from color-octet quarkonium formation mechanisms to $J/\psi$ hadroproduction at low $p_\perp$. We include transitions of color-octet $c\bar{c}$ states into ``direct'' $J/\psi$ and into $\chi_{1,2}$ which decay…
We propose measurement of transverse single spin asymmetry (SSA) in charmonium production as a probe of gluon Sivers function. We estimate SSA in low virtuality electroproduction of $J/\psi $ using color evaporation model of charmonium…