相关论文: In-medium broadening of nucleon resonances
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 investigate the influence of possible in-medium modifications of the S11(1535) in eta photoproduction in nuclei. Besides Fermi motion, Pauli blocking and binding effects also collisional broadening is accounted for. The in-medium width…
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 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…
A relativistic model for the quasifree exclusive photoproduction of $\eta$ mesons on nuclei is extended to include both non-local and medium effects. The reaction is assumed to proceed via the dominant contribution of the S$_{11}$(1535)…
Recent experimental results for meson photoproduction from nuclei obtained with TAPS at MAMI are analyzed in view of the suppression of the second nucleon resonance region in total photoabsorption. The cross sections can be split into a…
Properties of hadrons and their modification within strongly interacting matter provide a link between experimental observables and Quantum Chromodynamics (QCD) in the non-perturbative sector. The sensitivity of various observables to…
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…
In-medium effects in photon excitation of the S$_{11}$ resonance from nucleon and its decay to $\eta$-meson using the RMF approach is studied. We examine the in-medium effects by varing the Dirac fields of the nucleon and the S$_{11}$…
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)…
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…
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…
We calculate the quasifree photoproduction of pions and eta mesons on nuclei from 12C to 208Pb. Assuming that for the quasifree process the cross sections for pi/eta - photoproduction on a nucleon in medium are -- besides a lowering due to…
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 prompt photon production in high-energy nuclear collisions. We focus on the broadening of the intrinsic transverse momenta of the partons in the initial state from nuclear effects, and their influence on the prompt photon p_t…
We study inclusive omega photoproduction in nuclei and propose a measurement of the nuclear transparency ratio as a means to learn about the in-medium properties of the omega meson. To this end we are using the semi-classical…
We analyze the statistics of resonance widths in a many-body Fermi system with open decay channels. Depending on the strength of continuum coupling, such a system reveals growing deviations from the standard chi-square (Porter-Thomas) width…
A relativistic non-local model for the inclusive photoproduction of $\eta$ mesons from complex nuclei is introduced. The model is based on the dominance of the S$_{11}$(1535) resonance. We compare the results of our calculations with the…
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…
What effect do particle-emitting resonances have on the scattering cross section? What physical considerations are necessary when modelling these resonances? These questions are important when theoretically describing scattering experiments…