F. Messi

The polarization observables T, P, and H and their impact on gamma p -< p pi(0) multipoles

Data on the polarization observables T, P, and H for the reaction gamma p -> p pi(0) are reported. Compared to earlier data from other experiments, our data are more precise and extend the covered range in energy and angle substantially. The results were extracted from azimuthal asymmetries measured using a transversely polarized target and linearly polarized photons. The data were taken at the Bonn electron stretcher accelerator ELSA with the CBELSA/TAPS detector. Within the Bonn-Gatchina partial wave analysis, the new polarization data lead to a significant narrowing of the error band for the multipoles for neutral-pion photoproduction

N(1520) 3/2(-) Helicity Amplitudes from an Energy-Independent Multipole Analysis Based on New Polarization Data on Photoproduction of Neutral Pions

New data on the polarization observables T, P, and H for the reaction γp→pπ(0) are reported. The results are extracted from azimuthal asymmetries when a transversely polarized butanol target and a linearly polarized photon beam are used. The data were taken at the Bonn electron stretcher accelerator ELSA using the CBELSA/TAPS detector. These and earlier data are used to perform a truncated energy-independent partial wave analysis in sliced-energy bins. This energy-independent analysis is compared to the results from energy-dependent partial wave analyses.

Momentum dependence of the imaginary part of the

Abstract.The photoproduction of

\omega

\omega

- and

and

\eta^{\prime}

\eta^{\prime}

-nucleus optical potential

mesons off carbon and niobium nuclei has been measured as a function of the meson momentum for incident photon energies of 1.2-2.9GeV at the electron accelerator ELSA. The mesons have been identified via the

THE BGO-OD EXPERIMENT AT ELSA

\omega \rightarrow \pi^{0} \gamma \rightarrow 3 \gamma

Strangeness photoproduction at the BGO-OD experiment

and

The \(\eta^{\prime}\)-carbon potential at low meson momenta

\eta^{\prime} \rightarrow \pi^{0} \pi^{0}\eta \rightarrow 6 \gamma