Related papers: Observing the Odderon: Tensor Meson Photoproductio…
We discuss the production of two pion pairs in photon collisions at high energies. We calculate the according matrix elements in k_T-factorization and discuss the possibility to reveal the existence of the perturbative Odderon by charge…
We have investigated exclusive photoproduction of light vector mesons ($\omega$, $\rho$ and $\phi$) on the nucleon at low energies. In order to explore the questions concerning the so-called missing nucleon resonances, we first establish…
This Letter reports a measurement of the cross section for producing pairs of central prompt isolated photons in proton-antiproton collisions at a total energy of 1.96 TeV using data corresponding to 9.5/fb integrated luminosity collected…
The exclusive electroproduction of J/psi mesons, ep->epJ/psi, has been studied with the ZEUS detector at HERA for virtualities of the exchanged photon in the ranges 0.15<Q^2<0.8 GeV^2 and 2<Q^2<100 GeV^2 using integrated luminosities of 69…
A future gamma factory at CERN or accelerator-based gamma sources elsewhere can include the possibility of energetic twisted photons, which are photons with a structured wave front that can allow a pre-defined large angular momentum along…
The double vector meson production in two photon collisions is addressed assuming that the color singlet $t$-channel exchange carries large momentum transfer. We consider the non-forward solution of the BFKL equation at high energy and…
We estimate the leading order amplitudes for exclusive photon and meson electroproduction reactions at large Q^2 in the valence region in terms of skewed quark distributions. As experimental investigations can currently only be envisaged at…
We investigate the discovery potential of the $a_1(1260)$ photoproduction in the $\gamma p \to a_1(1260)^+ n$ and $\gamma p \to \pi^+\pi^+\pi^- n$ reactions via the $\pi$-exchange mechanism. For the $\gamma p \to \pi^+\pi^+\pi^- n$…
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)…
A consistent description of exclusive photoproduction of mesons at high momentum transfer t relies on a few effective degrees of freedom which can be checked against Lattice calculation or more effective models of QCD.
In this work we present the results of a theoretical analysis of the data on photoproduction of $f_0(980)$ meson in the laboratory photon energy between 3.0 and 3.8 GeV. A comparison is done to the measurements performed by the CLAS…
Differential and total cross-sections for photoproduction of gamma proton to proton pi0 omega and gamma proton to Delta+ omega were determined from measurements of the CB-ELSA experiment, performed at the electron accelerator ELSA in Bonn.…
The total cross section for the photoproduction process with a leading proton in the final state has been measured at gamma p centre-of-mass energies W of 91, 181 and 231 GeV. The measured cross sections apply to the kinematic range with…
The cross section for muon pair productions by electrons scattering over photons, $\sigma_{MPP}$, is calculated analytically in the leading order. It is pointed out that for the center-of-mass energy range, $s \geq 5 m^{2}_{\mu}$, the cross…
A recently developed model for $\rho$-meson propagation in dense hadronic matter is applied to total photoabsorption cross sections in $\gamma$-proton and $\gamma$-nucleus reactions. Within the vector dominance model the photon coupling to…
In this contribution I discuss prospects for photoproducing hybrid mesons at CEBAF, based on recent model results and experimental indications of possible hybrids. One excellent opportunity appears to be a search for the I=1, JPC=2+-,…
Strange and non-strange axial-vector meson radiative decays contribute to photon production in hadron gas. One- and two-hadron radiative decay modes of $b_{1}(1235)$, $a_{1}(1260)$ and $K_{1}(1270)$ are studied. At 200 MeV temperature and…
We calculate rates for hybrid meson production by electromagnetic and weak interactions in the flux-tube model. Applications include photo and electroproduction at Jefferson Laboratory and HERA, and the production of light strange and…
One of the open questions of the strong interaction theory is the existence of the Odderon, which is an unambiguous prediction of Quantum Chromodynamics, but still not confirmed in the experiment. In this paper we propose the study of the…
A new mechanism for hard diffraction based on the anomalous $f_1$ trajectory exchange, which we identify as the odd signature partner of the Pomeron, is suggested. We calculate the contribution of the $f_1$ exchange to elastic and…