Related papers: Absorption mechanisms in photon induced two-body k…
An experiment on the radiative pi^+ meson photoproduction from the proton (gamma p->gamma pi^+ n) was carried out at the Mainz Microtron MAMI in the kinematic region 537 MeV <E_{gamma}<817 MeV, 140^o<theta_{gamma-gamma'}^cm<180^o. The pi^+…
We discuss ${\gamma}{\gamma}\to {\pi}{\pi}$ reactions, starting from the two-pion threshold up to about $\sqrt{s_{{\gamma}{\gamma}}}$ = 6 GeV. We include the dipion continuum due to pion exchange (for ${\pi}^+{\pi}^-$) and ${\rho}^\pm$…
Three-body photodisintegration of 3He is calculated in the photon energy range 200 - 400 MeV assuming quasifree absorption on np pairs both in initial quasideuteron and singlet configurations. The model includes the normal nucleonic…
An analysis of incoherent photoproduction of $\eta$ mesons off the deuteron for photon energies from threshold to 800 MeV is presented. The dominant contribution, the $\gamma$N-$\eta$N amplitude, is described within an isobar model. Effects…
Photoproduction of $\pi\eta$-pairs from nucleons has been investigated from threshold up to incident photon energies of $\approx$~1.4~GeV. The quasi-free reactions $\gamma p\rightarrow p\pi^0\eta$, $\gamma n\rightarrow n\pi^0\eta$, $\gamma…
A reaction model for $\gamma + p \to J/\psi + p$ photoproduction, which exposes the $c \bar c$ content of the photon in making the transition $\gamma\to c\bar c + \mathbb P \to J/\psi$ and couples the intermediate $c \bar c$ system to the…
We propose a simple meson-exchange model of the photoproduction of $\rho$- and $\omega$-mesons off protons near threshold ($E_\gamma$ less than 2 GeV). This model provides a good description of the available data and implies a large…
The cross sections for electron induced two-nucleon knockout reactions are evaluated for the example of the $^{16}$O(e,e$'$pn)$^{14}$N reaction leading to discrete states in the residual nucleus $^{14}$N. These calculations account for the…
Photo disintegration of the deuteron and photo pionproduction on the deuteron are described in the region of the $\Delta$-resonance. The two reactions are unitarily coupled. A novel definition of electromagnetic exchange currents in the…
A theoretical possibility to determine the proton Compton scattering cross section from the reaction $ep\rightarrow ep\gamma$ is studied in the kinematics with a small transversal momentum transfer in the electron leg. With the exception of…
We develop a fully relativistic distorted wave impulse approximation model for electron- and photon-induced one proton knockout reactions. The relativistic mean field for the bound state and the Pauli reduction for the scattering state are…
The energy spectrum for high energy $\gamma$-rays ($E_\gamma \geq 10$ MeV) from the process $pp \to \gamma \gamma X$ emitted at $90^0$ in the laboratory frame has been measured at an energy below the pion production threshold, namely, at…
The cross sections of the ($e,e'N$) and ($\gamma,p$) reactions on $^{16}$O are calculated, for the transitions to the $1/2^{-}$ ground state and the first $3/2^{-}$ excited state of the residual nucleus, using single-particle overlap…
After recent improvements to the Pavia model of two-nucleon knockout from $^{16}$O with electromagnetic probes the calculated cross sections are compared to experimental data from such reactions. Comparison with data from a measurement of…
We show that the data on $\gamma p$ and $\gamma\gamma$ interactions can be derived from the $pp$ and $\bar p p$ forward scattering amplitudes using vector meson dominance and the additive quark model. The nucleon-nucleon data are…
A search for contributions to the reaction ep-> e pi^0 N^* from photon-Odderon fusion in the photoproduction regime at HERA is reported, at an average photon-proton centre-of-mass energy <W> = 215 GeV. The measurement proceeds via detection…
A comprehensive analysis of multiparticle emissions following photon induced reactions at intermediate energies is provided. Photon induced reaction is described in the energy range of $\sim 30-140$ MeV with an approach based on the…
We investigate photoproduction of $\omega$ off a nucleon target $\gamma N\to\omega N$ by using a Reggeized model where $\pi(135)+\sigma(500)+f_1(1285)+f_2(1270)$+Pomeron exchanges are included in the $t$-channel for the reaction at forward…
An analysis of the effects of meson exchange and isobar currents in exclusive (e,e'p) processes from O-16 under quasi-free kinematics is presented. A model that has probed its feasibility for inclusive quasi-elastic (e,e') processes is…
In this letter we study the high energy behavior of the forward differential cross section for the $^{18}O(\pi^+,\pi^-)^{18}Ne$ double charge exchange reaction. We have evaluated the sequential and the meson exchange current mechanisms. The…