In-Medium Properties of Hadrons

A diverse experimental program for the study of the photoproduction of mesons off nuclei has been carried out - and is still running - at the Mainz MAMI and Bonn ELSA electron accelerators with the TAPS, Crystal Barrel, and Crystal Ball calorimeters. It is motivated as a detailed study of the in-medium properties of hadrons and the meson - nucleus interactions. Typical examples for the in-medium behavior of vector mesons ($\omega$), scalar mesons ($\sigma$), and nucleon resonances (P$_{33}$(1232), S$_{11}$(1535), D$_{15}$(1520)) are discussed. Special attention is paid to meson - nucleus final state interactions.Comment: Proceedings of the Meson2006 IX Int. Workshop on Production, Properties and Interaction of Mesons, Cracow, Poland 09 - 14 June, 2006, to be published in Int. J. Mod. Phys.

Polarization Observables in eta and pi Production Using a Polarized Target with the Crystal Ball/TAPS at MAMI

Recent experiments using the Crystal Ball/TAPS setup at the MAMI accelerator in Mainz, Germany, continue to study the properties and the excitation spectrum of the nucleon with meson photoproduction. Electromagnetic excitations of the proton and neutron are essential for understanding their isospin decomposition. The electromagnetic coupling of photons to protons is different than that to neutrons in certain states. Hence, a complete partial wave analysis (PWA) can assist in yielding more information about any reaction, but requires the determination of polarization observables. Polarization observables play a crucial role as they are essential in disentangling the contributing resonant and non-resonant amplitudes, whereas cross section data alone is not sufficient for separating broad overlapping resonances. Preliminary results of polarization observables of η, single, and double π production off a polarized neutron (dButanol) target will be shown with comparison to predictions of recent multipole analyses. These results will greatly increase the world database on pseudoscalar meson production on neutrons

The nucleus ^198 Au investigated with neutron capture and transfer reactions. II. Construction of the level scheme and calculation of level densities

The level scheme of ^198 Au was constructed. Up to 1560 keV a total of 111 (d,p) and 125 (n,gamma) levels was included, frequently with spin and parity assignments. The results for level densities are calculated in interacting boson-fermion-fermion model (IBFFM) and Gaussian polynomial method (GPM) and are compared to the present data

The nucleus ^198 Au investigated with neutron capture and transfer reactions I. Experiments and evaluation

The transfer reaction ^197 Au(d,p)^198 Au was measured at the Tandem Accelerator in Munich. The ^197 Au(n,gamma)^198 Au and ^197 Au(n,e)^198 Au reactions were performed at the High Flux Reactor of ILL, Grenoble. Up to 1560 keV a total of 111 levels were observed by the (d,p) reaction and 125 by the (n,gamma) reaction. For many of the levels, spins and parities were assigned. Additional information was obtained from summed (n,gamma gamma) coincidences measured in Dubna

Proučavanje jezgre 198Au pomoću neutronskog uhvata i (d,p) reakcijom. II. Konstrukcija sheme nivoa i izračunavanje gustoće nivoa

The level scheme of 198Au was constructed. Up to 1560 keV a total of 111 (d,p) and 125 (n,γ) levels was included, frequently with spin and parity assignments. The results for level densities are calculated in interacting boson–fermion–fermion model (IBFFM) and Gaussian polynomial method (GPM) and are compared to the present data.Sastavljena je shema raspada 198Au. Do energije uzbude od 1560 keV, uključeno je 111 stanja određenih (d,p) reakcijom i 125 stanja (n,γ) reakcijom. Za mnoga stanja određeni su momenti impulsa i parnost. Primjenom modela uzajamno djelujućih bozon–fermion–fermiona i metode Gaussovih polinoma, izračunate su gustoće stanja i uspoređene s izmjerenim vrijednostima

Proučavanje jezgre 198au pomoću neutronskog uhvata i (d,p) reakcijom. I. Eksperimenti i procjena

The transfer reaction 197Au(d,p)198Au was measured at the Tandem Accelerator in Munich. The 197Au(n,γ) 198Au and 197Au(n,e)198Au reactions were performed at the High Flux Reactor of ILL, Grenoble. Up to 1560 keV a total of 111 levels were observed by the (d,p) reaction and 125 by the (n,γ) reaction. For many of the levels, spins and parities were assigned. Additional information was obtained from summed (n,γγ) coincidences measured in Dubna.Načinjena su mjerenja relacije 197Au(d,p)198Au pomoću tandem Van de Graaff akceleratora u Munchenu, a reakcije 197Au(n,γ) 198Au i 197Au(n,e)198Au proučavane su pri nuklearnom reaktoru u Institutu Lane–Laugevin u Grenoblu. Reakcijom (d,p) opaženo je do energije uzbude od 156 keV ukupno 111 nivoa, a reakcijom (n,γ) 125 nivoa. Za mnoge nivoe utvrđeni su momenti impulsa i parnosti. Dodatni su podaci postignuti mjerenjem zbrojnih (n,γγ) sudara u Institutu u Dubni

Proučavanje jezgre 198au pomoću neutronskog uhvata i (d,p) reakcijom. I. Eksperimenti i procjena

The transfer reaction 197Au(d,p)198Au was measured at the Tandem Accelerator in Munich. The 197Au(n,γ) 198Au and 197Au(n,e)198Au reactions were performed at the High Flux Reactor of ILL, Grenoble. Up to 1560 keV a total of 111 levels were observed by the (d,p) reaction and 125 by the (n,γ) reaction. For many of the levels, spins and parities were assigned. Additional information was obtained from summed (n,γγ) coincidences measured in Dubna.Načinjena su mjerenja relacije 197Au(d,p)198Au pomoću tandem Van de Graaff akceleratora u Munchenu, a reakcije 197Au(n,γ) 198Au i 197Au(n,e)198Au proučavane su pri nuklearnom reaktoru u Institutu Lane–Laugevin u Grenoblu. Reakcijom (d,p) opaženo je do energije uzbude od 156 keV ukupno 111 nivoa, a reakcijom (n,γ) 125 nivoa. Za mnoge nivoe utvrđeni su momenti impulsa i parnosti. Dodatni su podaci postignuti mjerenjem zbrojnih (n,γγ) sudara u Institutu u Dubni

The nucleus ^198 Au investigated with neutron capture and transfer reactions. II. Construction of the level scheme and calculation of level densities

The level scheme of ^198 Au was constructed. Up to 1560 keV a total of 111 (d,p) and 125 (n,gamma) levels was included, frequently with spin and parity assignments. The results for level densities are calculated in interacting boson-fermion-fermion model (IBFFM) and Gaussian polynomial method (GPM) and are compared to the present data

The nucleus ^198 Au investigated with neutron capture and transfer reactions I. Experiments and evaluation

The transfer reaction ^197 Au(d,p)^198 Au was measured at the Tandem Accelerator in Munich. The ^197 Au(n,gamma)^198 Au and ^197 Au(n,e)^198 Au reactions were performed at the High Flux Reactor of ILL, Grenoble. Up to 1560 keV a total of 111 levels were observed by the (d,p) reaction and 125 by the (n,gamma) reaction. For many of the levels, spins and parities were assigned. Additional information was obtained from summed (n,gamma gamma) coincidences measured in Dubna