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Recent experimental results for the in-medium properties of hadrons obtained with photoproduction of mesons from nuclei are discussed. The experiments were done with the TAPS detector at the tagged photon beam of the MAMI accelerator in…
Inclusive studies of nuclear photoabsorption have provided clear evidence of medium modifications in the properties of hadrons. However, the results have not been explained in a model independent way. A deeper understanding of the situation…
We construct the formula for the photonuclear total absorption cross section using the projection method and the unitarity relation. Our treatment is very effective when interference effects in the absorption processes on a nucleon are…
Differences in the photoproduction of mesons on the free proton and on nuclei are expected to reveal changes in the properties of hadrons. Inclusive studies of nuclear photoabsorption have provided evidence of medium modifications. However,…
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…
Medium effects as a function of the mass number $A$ are studied in the total photonuclear cross section from the $\Delta$-resonance region up to the region where shadowing effects are known to exist. A consistent picture is obtained by…
Photoproduction of mesons off quasi-free nucleons bound in the deuteron allows to study the electromagnetic excitation spectrum of the neutron and the isospin structure of the excitation of nucleon resonances. The database for such…
We calculate the total photoabsorption cross section on nuclei in the energy range from 300 MeV to 1 GeV within the framework of a semi-classical phase space model. Besides medium modifications like Fermi motion and Pauli blocking we focus…
We analyze the effects of an in-medium broadening of nucleon resonances on the exclusive photoproduction of mesons on nuclei as well as on the total photoabsorption cross sections in a transport calculation. We show that the resonance…
Differences in the photoproduction of mesons on the free proton and on nuclei are expected to reveal changes in the properties of hadrons. Inclusive studies of nuclear photoabsorption have provided evidence of medium modifications. However,…
We calculate the total photoabsorption cross section and cross sections for inclusive pion and eta photoproduction in nuclei in the energy range from 300 MeV to 1 GeV within the framework of a semi-classical BUU transport model. Besides…
The study of baryon resonances via meson photoproduction reactions on the free proton and on nucleons in the nuclear medium is discussed. Special emphasis is laid on the production of neutral mesons which due to the suppression of…
The in-medium properties of the D13(1520) nucleon resonance were studied via photoproduction of pi0-mesons from nuclei (C, Ca, Nb, Pb) with the TAPS-detector at the Mainz MAMI accelerator. The inclusive (single and multiple pion production)…
Recent experimental results for the in-medium properties of nucleon resonances are discussed. The experiments were done with the TAPS detector at the tagged photon beam of the MAMI accelerator in Mainz. Measured was the photoproduction of…
Inclusive studies of nuclear photoabsorption have provided clear evidence of medium modifications but the results have not yet been explained in a model independent way. A deeper understanding of the situation is anticipated from a detailed…
An improved procedure is suggested for finding the total photoabsorption cross section on the neutron from data on the deuteron at energies < 1.5 GeV. It includes unfolding of smearing effects caused by Fermi motion of nucleons in the…
Recent results for the photoproduction of mesons off nuclei are reviewed. These experiments have been performed for two major lines of research related to the properties of the strong interaction. The investigation of nucleon resonances…
In the present work we explore the inclusive $\psi(2S)$ meson photoproduction from nuclei near the kinematic threshold within the collision model, based on the nuclear spectral function, for incoherent direct photon--nucleon charmonium…
Photoproduction of $\eta$ mesons off $^{12}$C, $^{40}$Ca, $^{93}$Nb, and $^{nat}$Pb nuclei has been measured with a tagged photon beam with energies between 0.6 and 2.2 GeV. The experiment was performed at the Bonn ELSA accelerator with the…
We present a simple model for the $\gamma N \to \pi \pi N$ reaction which reproduces the cross sections of the $\pi^+ \pi^- p, \pi^+ \pi^- n, \pi^+ \pi^0 n$ and $\pi^- \pi^0 p$ channels over the range of the energies 0.41-0.85 GeV. We use…