Near threshold photoproduction of eta mesons off the proton.

1995

We have measured precise total and differential cross sections for the reaction $\ensuremath{\gamma}p\ensuremath{\rightarrow}p\ensuremath{\eta}$ from threshold to 790 MeV at the MAMI accelerator in Mainz with the neutral meson spectrometer TAPS. Resonance parameters of the ${S}_{11}$(1535) resonance and the electromagnetic coupling $\ensuremath{\gamma}p\ensuremath{\rightarrow}{S}_{11}$ have been extracted from the data. Contributions from the ${D}_{13}$(1520) resonance to $\ensuremath{\eta}$ photoproduction in the threshold region have been identified for the first time via interference terms in the angular distributions.

Krusche et al. reply.

1995

Radiative Pion Photoproduction from the Proton and π + Meson Polarizabilities

1995

We study the possibility of investigating radiative pion photoproduction from the proton at the microtron MAMI-B with the aim to obtain an experimental information about the π + meson polarizabilities. It is shown that an exposition time of about 30 days will allow to determine the π + meson polarizability with quite high accuracy.