Related papers: Evidence that the Pomeron transforms as a non-cons…
We present a nonperturbative QCD calculation of diffractive vector meson production in virtual photon nucleon scattering at high energy. We use the nonperturbative model of the stochastic QCD vacuum which yields linear confinement and makes…
A study has been made of pseudoscalar mesons produced centrally in pp interactions. The results show that the eta and etaprime appear to have a similar production mechanism which differs from that of the pi0. The production properties of…
Two-body bound states such as mesons are described by solutions of the Bethe-Salpeter equation. We discuss recent results for the pseudoscalar and vector meson masses and leptonic decay constants, ranging from pions up to c\bar{c} bound…
We report results of our ongoing investigation concerning semileptonic decays of heavy pseudoscalar mesons into pseudoscalar and vector mesons. Particular attention is paid to uncertainties in the $q^2$ and the heavy quark mass dependence…
Holographic models of QCD, collectively known as AdS/QCD, have been proven useful in deriving several properties of hadrons. One particular feature well reproduced by such models is the Regge trajectories, both for mesons and glueballs. We…
We have studied in perturbative QCD all independent helicity amplitudes describing the photoproduction of light vector mesons at large $t$. We found a new hard production mechanism which is related to the possibility for a real photon to…
High-statistics total cross sections for the vector meson photoproduction at the threshold: $\gamma p\to\omega p$ (from A2 at MAMI, ELPH, and CBELSA/TAPS), $\gamma p\to \phi p$ (from CLAS and LEPS), and $\gamma p\to J/\psi p$ (from GlueX)…
At high energy, exclusive meson photo- and electro-production give access to the structure of hadronic matter. At low momentum transfers, the exchange of a few Regge trajectories leads to a comprehensive account of the cross-sections. Among…
We study the role of semi-classical QCD vacuum solutions in high energy scattering by considering the instanton contribution to hadronic cross sections. We propose a new type of instanton-induced interactions (``instanton ladder'') that…
In the framework of Anisotropic Chromodynamics, a non-perturbative realization of QCD, we develop the Low-Nussinov picture of the Pomeron. In this approach all the usual problems of low pT perturbative calculations (infrared divergence) are…
We demonstrate that the explicit mass dependence of the exponent in the power--like energy behavior of the vector--meson production cross-section in the processes of virtual photon interactions with a proton gamma^*p --> Vp obtained in the…
The Pomeron, which dominates high energy elastic and diffractive hadronic processes, must be largely gluonic in nature. We use a recent picture of a scalar glueball/sigma system with coupling of the sigma to glue determined from experiment…
This is a talk, given at Diffraction'2000, Sept. 2 - 7, Centraro, Italy. This talk is a brief presentation of our view on the Pomeron, as a non-perturbative QCD phenomenon but from sufficiently short distances. Our approach is based on the…
Glueballs are considered to be bound states of constituent gluons. Relativistic wave equation for two massive gluons interacting by the funnel-type potential is analyzed. Using two exact asymptotic solutions of the equation, we derive an…
We briefly review the approach for strong coupling calculation of glueball masses based on the duality between supergravity and Yang-Mills theory. Earlier work is extended to non-zero spin. Fluctuations in the gravitational metric lead to…
Using a non--relativistic gluon bound--state model for glueballs (G), we compute the subprocess $q\,\bar q\, \to\, G\,\pi$, and we therefrom derive the yield of the overall reaction $p\,\bar p\, \to\, G\,\pi X$, assuming the glueball and…
The production of $J^{PC} = 1^{++},0^{-+}$ and $2^{-+}$ mesons in double tagged $e^+e^- \to e^+e^-R$ is calculated and found to have the same polarisation and dynamical characteristics as observed in $pp \to ppR$. Implications for the spin…
A study of the centrally produced ppbar, ppbarpi, ppbarpipi and lambda lambda channels has been performed in pp collisions using an incident beam momentum of 450 GeV/c. No significant new structures are observed in the mass spectra,…
We show that the lowest-order QCD calculation in a simple model of elastic vector-meson production does reproduce correctly the ratios of cross sections for rho, phi and J/psi, both in photoproduction and in high-Q2 quasi-elastic…
Heavy flavour production like $J/\psi$ and $D$- meson production in scattering of electrons/unpolarized protons off polarized proton target offer promising probes to investigate gluon Sivers function. In this talk, I will summarize our…