Related papers: Leptoproduction of J/\psi
We study the associated $J/{\psi}$ and direct photon production in the high-energy factorization, as it is formulated in the parton Reggeization approach, using two different models for the hadronization of a heavy quark-antiquark pair into…
We evaluate the production cross section for direct J/psi integrated in P_T for various collision energies of the LHC in the QCD-based Colour-Singlet Model. We consider the LO contribution from gluon fusion as well as the one from a fusion…
Color-octet contributions to the associate J/psi+gamma hadroproduction are studied in detail, and found to be negligible, compared to the ordinary color-singlet contribution. Within the color-singlet model the J/psi+gamma production in the…
We present an analysis of the preliminary experimental data of direct j/psi production in e^e- process at low energies. We find that the color-octet contributions are crucially important to the cross section at this energy region, and their…
Recent experiments by the CLEO III detector at CESR indicate that the $\jpsi$ spectrum produced in $\Upsilon$ decay is in conflict with Non-Relativistic QCD (NRQCD) calculations. The measured $\jpsi$ momentum distribution is much softer…
We present theoretical predictions for the transverse-momentum distribution of J/psi mesons promptly produced in gamma gamma collisions within the factorization formalism of nonrelativistic quantum chromodynamics, including the…
Recent observations of the J/psi spectrum produced in e^+e^- collisions at the Upsilon(4S) resonance are in conflict with fixed-order calculations using Non-Relativsitic QCD effective theory (NRQCD). One problem is an enhancement in the…
Calculations for inclusive J/psi production in Upsilon decay through the color-octet mechanisms b\bar b[^3S_1, 1] -> c \bar c[^{2s+1}L_J, 8] + g are presented. It is shown that these O(alpha^5_sv^4_c) contributions compete with other…
In the framework of $k_T$-factorization approach, the production and polarization of prompt $J/\psi$ mesons at the LHC energies is studied. Our consideration is based on the non-relativistic QCD formalism for bound states and off-shell…
We study the production of a prompt J/psi meson in association with a prompt photon in ep deep-inelastic scattering within the factorisation formalism of non-relativistic quantum chromodynamics (NRQCD) and demonstrate that this process…
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 calculate the cross section for hadroproduction of a pair of heavy quarks in a 3S1 color-singlet state at next-to-leading order in QCD. This corresponds to the leading contribution in the NRQCD expansion for J/psi and Upsilon production.…
We investigate the $J/\psi$ + c + $\bar{c}$ photoproduction in $e^+ e^-$ collision at the LEP II energy. The physical motivations for this study are: 1) such next-to-leading order(NLO) process was not considered in previous investigations…
We calculate the next-to-leading order (NLO) QCD corrections to the $J/\psi +W$ production at the LHC, and provide the theoretical distribution of the $J/\psi$ transverse momentum. Our results show that the differential cross section…
We consider J/psi meson photoproduction on protons at high energies at the leading order in alpha_s using conventional parton model and k_t-factorization approach of QCD. It is shown that in the both cases the colour singlet mechanism gives…
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…
Based on the factorization framework of nonrelativistic quantum chromodynamics, we study the associated $J/\psi+c+\bar{c}$ photoproduction process at next-to-leading order in $\alpha_s$ and leading order in the velocity expansion. The total…
The associated production of J/psi + gamma at the LHC is studied within the NRQCD framework. The signal we focus on is the production of a J/psi and an isolated photon produced back-to-back, with their transverse momenta balanced. It is…
The next to leading order (NLO) QCD corrections to J/psi polarization of hadronproduction at Tevatron and LHC are calculated. The results show that the J/psi polarization is extremely changed from more transversal polarization at leading…
We consider the prompt hadroproduction of J/psi, psi' and the Upsilon (1S,2S,3S) states caused by the fusion of a symmetric colour-octet two-gluon state and an additional gluon. The cross sections are calculated in leading-order…