Related papers: Higher-Order Effects on Inelastic J/psi Photoprodu…
Recently unpolarized and polarized $J/\psi \,(\Upsilon)$ production at the Electron-Ion Collider (EIC) has been proposed as a new way to extract two poorly known color-octet NRQCD long-distance matrix elements: $\langle0\vert{\cal…
We calculate \alpha^{2}\alpha_{s}^{2} order QED contribution to J/\psi production in pp(\bar{p})\to J/\psi+c\bar{c} color-singlet process at the Tevatron and LHC in the framework of non-relativistic QCD. The contribution of the interference…
In the framework of k_T-factorization QCD approach and the colour singlet model we consider J/\psi inelastic photo- and leptoproduction processes at HERA. We investigate the dependences of the single differential and double differential…
The cross sections for inelastic photoproduction of J/psi and psi^prime mesons have been measured in ep collisions with the ZEUS detector at HERA, using an integrated luminosity of 468 pb-1 collected in the period 1996--2007. The psi^prime…
We present a measurement of the inelastic, non diffractive J/$\psi$ photoproduction cross section in the reaction $e^{+} p \to e^{+} {J}/\psi X$ with the ZEUS detector at HERA. The J/$\psi$ was identified using both the $\mu^{+}\mu^{-}$ and…
We compute the relativistic corrections to the color-singlet contribution to gluon fragmentation into a J/psi at relative order v^4, making use of the nonrelativistic QCD (NRQCD) factorization approach. The corresponding full-QCD process…
The amplitude for $\gamma p \to V p$, where $V$ is a $J/\psi$ or $\Upsilon$ ground state or excited vector meson, is calculated in a pQCD $k_{T}$-factorization approach. We use this amplitude to predict the cross section for exclusive…
We calculate the cross section of J/psi plus prompt-photon inclusive production in gamma gamma collisions at next-to-leading order within the factorization formalism of nonrelativistic quantum chromodynamics (NRQCD) focusing on direct…
Non-Relativistic QCD (NRQCD) has provided a consistent framework for the physics of quarkonia. The colour-octet Fock components predicted by NRQCD have important implications for the phenomenology of quarkonium production in experiments. We…
We present a calculation for the polarizations of $J/\psi$ and $\psi'$ produced in the hadron collisions at the Fermilab Tevatron. Various color octet channels including ${}^1S_0^{(8)}$, ${}^3P_J^{(8)}$, and ${}^3S_1^{(8)}$ as well as…
We discuss prompt production of $J/\psi$ mesons in proton-proton collisions at the LHC within NRQCD $k_t$-factorization approach using Kimber-Martin-Ryskin (KMR) unintegrated gluon distributions (UGDF). We include both direct color-singlet…
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…
In the framework of kt-factorization approach, the production and polarization of prompt psi(2S) mesons in pp collisions at the LHC energies is studied. Our consideration is based on the non-relativistic QCD formalism for bound states and…
The production of J/Psi mesons in gamma gamma collisions allows for a test of factorization in color-octet processes as predicted by NRQCD and observed at the Tevatron. We calculate the cross sections for J/Psi production with direct and…
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 present the leading order differential and total rates for J/\psi production at LEP. By leading order we mean all terms of the form alpha_s[alpha_s log(M_Z^2/M_{psi}^2)]^n and alpha_s^{n+1} log^l(z^2) log^m(M_Z^2/M_{psi}^2), (l+m=2n-1),…
To clarify the outstanding problem in charmonium production that existing theories cannot explain the observed cross sections of $\chi_{cJ}$ (J=0,1,2) and ratio $R_{\chi_c}=\sigma_{\chi_{c2}}/\sigma_{\chi_{c1}}\approx 0.75$ (in contrast to…
The exclusive photoproduction of vector mesons ($J/\psi$ and $\phi$) are investigated by taking into account the next-to-leading order corrections in the framework of Color Glass Condensate. We confront the next-to-leading order modified…
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…
We study the contribution of double parton scattering (DPS) to the associated production of $J/\psi$ mesons and photons with large transverse momenta in proton-proton collisions. Cross sections are computed within high-energy factorization…