Related papers: Exclusive heavy vector meson electroproduction to …
We calculate the cross-sections of diffractive single hadron photo- or electroproduction with large $p_T$, on a nucleon or a nucleus in the shockwave formalism. We use the hybrid formalism mixing collinear factorization with high energy…
In this work the $k_{\perp}$-factorization formalism is applied to compute the exclusive $Z^0$ boson photoproduction in $ep$ and $eA$ collisions. The study is also extended to $pp$ and $AA$ processes. The nuclear effects are investigated…
Hard diffractive photo- and electroproduction of heavy vector mesons ($J/\psi$ and $\Upsilon$) is evaluated within the leading $\alpha_s\ln{Q^2 \over\Lambda_{QCD}^2}$ approximation of QCD. In difference from our earlier work on that…
The single diffractive cross section for heavy quarks production is calculated in next-no-leading order (NLO) in nucleus-nucleus collisions. Such processes are expected to occur at the LHC. We start using the hard diffractive factorization…
The NLO QCD calculation for the photoproduction of the isolated photon with a large $p_T$ at the HERA $ep$ collider is presented. The single resolved photon contribution and the QCD corrections of order $\alpha_s$ to the Born term are…
Photoproduction of a pair of particles with large invariant mass is a natural extension of collinear QCD factorization theorems which have been much studied for deeply virtual Compton scattering and deeply virtual meson production. We…
In view of possible photoproduction studies in ultraperipheral heavy-ion collisions at the LHC, we briefly review the present theoretical understanding of photons and hard photoproduction processes at HERA, discussing the production of…
We discuss heavy quarkonium production through parton fragmentation, including a review of arguments for the factorization of high-p_T particles into fragmentation functions for hadronic initial states. We investigate the further…
Exclusive rho0 electroproduction at HERA has been studied with the ZEUS detector, using 120 pb{-1} integrated luminosity, in the kinematic range of photon virtuality of 2 < Q2 < 160 GeV2, and gamma* p center-of-mass energy of 32 < W < 180…
The collinear factorization framework allows to describe the exclusive photoproduction of a $\gamma\,\rho$ pair in the generalized Bjorken regime in terms of a perturbatively calculable coefficient function and universal generalized parton…
We present calculations of heavy quark and quarkonium production at CERN LEP2 in the k_T-factorization QCD approach. Both direct and resolved photon contribution are taken into account. The conservative error analisys is performed. The…
The inclusive $J/\Psi$ production by direct and resolved photoproduction in the $\gamma$p scattering is calculated based on the nonrelativistic quantum chromodynamics (NRQCD) factorization formalism, which is in good agreement with the…
We study exclusive vector meson photoproduction, $\gamma p \to V + p$ with $V=J/\psi$ or $\Upsilon$, at NLO in collinear factorisation, in order to examine what may be learnt about the gluon distribution at very low $x$. We examine the…
Based on the factorization formalism of nonrelativistic quantum chromodynamics (NRQCD), we calculate the production cross section for the charmonium and the bottomonium produced by the hard photoproduction processes and fragmentation…
The NLO QCD calculation for the photoproduction of the isolated photon with a large pT at the HERA ep collider is presented. The single resolved photon contribution and the QCD corrections of order alpha_s to the Born term are consistently…
We formulate and prove a QCD factorization theorem for hard exclusive electroproduction of mesons in QCD. The proof is valid for the leading power in Q and all logarithms. This generalizes previous work on vector meson production in the…
We outline a proof of factorization in exclusive processes, taking into account the presence of soft and collinear modes of arbitrarily low energy, which arise when the external lines of the process are taken on shell. Specifically, we…
We present a study of $J/\psi + jet$ diffractive production in the direct photon process at HERA based on the factorization theorem for lepton-induced hard diffractive scattering and the factorization formalism of the nonrelativistic QCD…
Photoproduction is an important mode for the production of jets and electro-weak particles at lepton--lepton and lepton--hadron colliders and allows for interesting studies of exclusive production at hadron--hadron colliders. In this talk,…
The rates for diffractive quarkonium plus prompt-photon associated production at the LHC are estimated. The theoretical framework considered in the J/Psi (or Upsilon) production associated with a direct photon at the hadron collider is the…