Related papers: Exclusive J/\psi Productions at e^+ e^- Colliders
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 study pp and p\bar p collisions which lead to the exclusive production of J/psi or Upsilon from the pomeron-odderon and the pomeron-photon fusion. We calculate scattering amplitudes of these processes in the lowest order approximation…
We propose to use transverse momentum $p_T$ distribution of $J/\psi$ production at the future Electron Ion Collider (EIC) to explore the production mechanism of heavy quarkonia in high energy collisions. We apply QCD and QED collinear…
Both charm and bottom quarks form nonrelativistic bound states analogous to positronium. The J/psi and psi(2S) charmonium states and the first three Upsilon(nS) bottomonium states, all spin-triplet S-wave quarkonium states below…
The production of a quarkonium -- pair in exclusive and diffractive processes in $pp$ collisions at the LHC and FCC energies is investigated. We consider the $J/\Psi J/\Psi$ and $\Upsilon \Upsilon$ production in these processes and present…
Recently, several surprising experimental observations in the production of heavy quarkonium have been reported. In $e^+e^-$ annihilation at $\sqrt{s}=10.6$ GeV, Belle Collaboration finds that $J/\psi$ mesons are predominantly produced in…
Recent measurements of J/psi production in e^+ e^- colliders pose a challenge to the NRQCD factorization theorem for quarkonium production. Discrepancies between leading order calculations of color-octet contributions and the momentum…
We report that, unlike most inclusive quarkonium-production processes, the production rate for p p -> J/psi+Upsilon+X dominantly depends on two not well-known long-distance nonrelativistic QCD matrix elements, <O_8^{J/psi}(^3S_1)> and…
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…
The double J/psi production in p\bar{p} collision is revisited. It is found that the J/\psi pair production rate at leading order with p_T > 4 GeV in conventional scheme is larger than the rate derived from color-octet mechanism by a factor…
The transverse momentum ($p_t$) distributions of production and polarization for $J/\psi$ measured by CDF Collaboration are still challenging our understanding of the heavy quarkonium production mechanism even with recent significant…
We study the exclusive production of J/psi or Upsilon in pp and bar pp collisions, where the meson emerges from the pomeron--odderon and the pomeron--photon fusion. We estimate the cross sections for these processes for the kinematical…
We calculate the cross sections for the direct hadroproduction of J/psi and Upsilon associated with a heavy-quark pair of the same flavour at leading order in alpha_S and v in NRQCD. These processes provide an interesting signature that…
We give an overview of the present status of knowledge of the production of J/psi, psi' and Upsilon in high-energy hadron collisions. We first present two early models, namely the Colour-Singlet Model (CSM) and the Colour-Evaporation Model…
We calculate \alpha^{2}\alpha_{s}^{2} order QED contribution to J/\psi production in pp(\bar{p})\to J/\psi+c\bar{c} color-singlet process at the Tevatron and LHC in the framework of non-relativistic QCD. The contribution of the interference…
We proceed for the first time to the evaluation of the Born cross section for J/psi+eta(c) production, namely via g+g -> J/psi+eta(c)+g, and show that it has a harder P_T spectrum than the J/psi-pair yield at Born level. If one stuck to a…
We consider the energy and the polar angle distributions of J/\psi's produced via the color-singlet and the color-octet (^3S_1^{(8)}) mechanisms in Z^0 \to J/\psi +X at LEP. Since both distributions of the J/\psi produced via color-octet…
We analyze the exclusive charmonium $J/\psi+\eta_c$ pair production in $e^+e^-$ annihilation using the nonfactorized perturbative QCD and the light-front quark model(LFQM) that goes beyond the peaking approximation. We effectively include…
We investigate the inclusive production of double quarkonia ($J/\psi$, $\psi(2S)$, $\Upsilon$ mesons) in polarized hadron-hadron collisions, considering the kinematic configuration where the transverse momentum of each pair of bound states…
In this paper we study the high energy exclusive photoproduction of heavy quarkonia pairs in the leading order of the strong coupling constant $\alpha_{s}$. In the suggested mechanism the quarkonia pairs are produced with opposite charge…