Münster 2017 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

HK: Fachverband Physik der Hadronen und Kerne

HK 38: Hadron Structure and Spectroscopy V

HK 38.2: Vortrag

Donnerstag, 30. März 2017, 14:30–14:45, F 5

Measurement of the double polarization observable G in the reactions γ p → p π⁰ / n π⁺ — •Karsten Spieker for the A2 collaboration — Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn

The nucleon excitation spectrum consists of many overlapping resonances. To obtain information about the contributing resonances, several well chosen single and double polarization observables have to be measured for different final states. These observables are providing the necessary data base for a unique Partial Wave Analyses (PWA) to identify the resonances and determine their properties.
The new polarization observable data reported in this talk were measured with the Crystal Ball experiment at MAMI in Mainz, using polarized photons and polarized nucleons. The setup covers nearly 4π of the solid angle and has a high detection efficiency for neutral and charged final states. The preliminary results of the double polarization observable G in the reactions γ p → p π⁰ and γ p → n π⁺ are presented. They have been determined in an energy range E_γ = 266–860 MeV, using a linearly polarized photon beam in combination with a longitudinally polarized butanol target.
Supported by the Deutsche Forschungsgemeinschaft (SFB1044, SFB/TR16) and Schweizerischer Nationalfonds.