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The reaction $p({e,e}^{\ensuremath{'}}p){\ensuremath{\pi}}^{0}$ has been studied very close to threshold $\ensuremath{\Delta}W\ensuremath{\le}4\mathrm{MeV}$ and at 4-momentum transfer ${Q}^{2}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.1(\mathrm{GeV}/c{)}^{2}$. The scattered electron and the kinematically focused recoil proton were detected in coincidence using the 3-magnetic spectrometer setup at the Mainz Microtron MAMI. The transverse and longitudinal as well as the longitudinal-transverse and the transverse-transverse interference structure functions have been determined. From the data the $s$-wave multipoles ${E}_{0+}$ and ${L}_{0+}$ have been extracted. The experimental results are compared to recent calculations in chiral perturbation theory.

Forward-angle coincident electroproduction cross sections of charged pions from ${}^{3}\mathrm{He}$ have been measured at electron energies ${E}_{0}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}855$, 675, 600, and 555 MeV. The overall features of the data for energy transfers of $\ensuremath{\omega}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}370$ to 430 MeV with pions detected along the momentum transfer axis are reproduced in terms of a microscopic model, including pole terms, final state rescattering and produced and preformed $\ensuremath{\Delta}$ resonances. Separation of the cross section into its longitudinal and transverse parts was performed at ${Q}^{2}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.045\phantom{\rule{0ex}{0ex}}(\mathrm{GeV}/c{)}^{2}$. The longitudinal part of the cross section in the ${\ensuremath{\pi}}^{+}$ channel does not contradict with the assumption of a preformed ${\ensuremath{\Delta}}^{++}$.

We have measured the first complete angular correlations of {alpha}-particle emission from the {sup 16}O isoscalar giant quadrupole resonance (GQ{sub 0}R) following excitation by inelastic electron scattering. Analysis of these determines the GQ{sub 0}R strength distribution and resolves a discrepancy between previous results from photonuclear excitation and inelastic {alpha} scattering.

The interference response function f{sub LT}(R{sub LT}) of the {sup 2}H(e,e{sup '}p)n reaction has been determined at squared four-momentum transfer Q{sup 2}=0.33 (GeV/c){sup 2} and for missing momenta up to p{sub m}=0.29 GeV/c. The results have been compared to calculations that reproduce f{sub LT} quite well but overestimate the cross sections by 10-20% for missing momenta between 0.1 GeV/c and 0.2 GeV/c.