Related papers: Dynamical study of $\gamma^*N \leftrightarrow \Del…
We have carried out a comparative study of the electronic specific heat and electronic structure of $\alpha$ and $\delta$-plutonium using dynmical mean field theory (DMFT). We use the perturbative T-matrix and fluctuating exchange (T-matrix…
A dynamical model based on effective Lagrangians is proposed to describe the bremsstrahlung reaction $ \pi N \to \pi N \gamma$ at low energies. The $\Delta(1232)$ degrees of freedom are incorporated in a way consistent with both,…
The deformation of viscoelastic drops under electric fields plays a crucial role in applications such as microfluidics, inkjet printing, and electrohydrodynamic manipulation of complex fluids. This study examines the deformation and breakup…
Hybrid/exotic meson spectroscopy searches at Jefferson Lab require the accurate theoretical description of the production mechanism in peripheral photoproduction. We develop a model for $\pi\Delta$ photoproduction at high energies ($5 \leq…
The Dalitz decay eta -> e^+ e^- gamma has been measured in the gamma p -> eta p reaction with the Crystal Ball and TAPS multiphoton spectrometers, together with the photon tagging facility at the Mainz Microtron MAMI. The experimental…
Damping of an electromagnetic wave in a strong magnetic field is analyzed in the kinematic region near the threshold of electron-positron pair production. Damping of the electromagnetic field is shown to be noticeably nonexponential in this…
We show that, within a meson-exchange dynamical model describing well most of the existing pion electromagnetic production data up to the second resonance region, one is also able to obtain a good agreement with the pi^0 photo- and…
Electroproduction form factors describing the $\gamma^\ast p \to \Delta^+(1232), \Delta^+(1600)$ transitions are computed using a fully-dynamical diquark-quark approximation to the Poincar\'e-covariant three-body bound-state problem in…
The photoproduction of a neutral pion on the deuteron is considered in the energy region around the eta threshold, where a bump-like structure was observed at very backward pion angles. Different dynamical aspects which may be responsible…
A dynamical model based on effective Lagrangians is proposed to describe the bremsstrahlung reaction $ \pi N \to \pi N \gamma$ at low energies. The $\Delta(1232)$ degrees of freedom are incorporated in a way consistent with both,…
Recent data for $\eta$ and $\eta\prime$ photoproduction on protons obtained by the A2 Collaboration at MAMI are presented. The total cross section for $\eta$ photoproduction demonstrates a cusp at the energy corresponding to the…
The reactions $\gamma p\to \eta p$ and $\gamma p\to \eta' p$ have been measured from their thresholds up to the center-of-mass energy $W=1.96$GeV with the tagged-photon facilities at the Mainz Microtron, MAMI. Differential cross sections…
We report results on the $\pi$-$\gamma$ transition form factor obtained within the hard scattering approach including transverse momentum effects and Sudakov corrections. The results clearly favor distribution amplitudes close to the…
Coherent photoproduction of \pi 0\eta\ on the deuteron, He3 and He4 nuclei is considered in the energy region from threshold to the lab photon energy 1.2 GeV. The transition amplitude is derived using impulse approximation. Effects of pion…
The $\eta N$ final state is isospin-selective and thus provides access to the spectrum of excited nucleons without being affected by excited $\Delta$ states. To this end, the world database on eta photoproduction off the proton up to a…
The development of a dynamical model for investigating the nucleon resonances using the reactions of meson production from \pi N, \gamma N, N(e,e'), and N(\nu,{\it l}) reactions is reviewed. The results for the \Delta (1232) state are…
Nuclear electromagnetic currents derived in a chiral-effective-field-theory framework including explicit nucleons, $\Delta$ isobars, and pions up to N$^2$LO, {\it i.e.} ignoring loop corrections, are used in a study of neutron radiative…
A combination of Density Functional Theory and the Dynamical Mean Field theory (DMFT) is used to calculate the magnetic susceptibility, heat capacity, and the temperature dependence of the valence band photoemission spectra. The…
Very recent data for the reaction gamma{d} --> eta{np} are analyzed within a model that includes contributions from the impulse approximation and next order corrections due to the np and eta{N} interactions in the final state. Comparison…
Recent JLab data of the differential cross section for the reaction p(e,e'p)pi0 in the invariant mass region of 1.1 < W < 1.4 GeV at four-momentum transfer squared Q^2= 2.8 and 4.0 (GeV/c)$^2$ are analyzed with two models, both of which…