High precision (E,E') and (E,E'P) experiments at Amsterdam

The nuclear structure research program at NIKHEF-K with electron and photon beams from the 500 MeV high-duty factor medium-energy electron accelerator (MEA) contains the following main elements; high-resolution (1X10/sup -4/) single-arm electron-scattering experiments to investigate properties of nuclear ground states and discrete energy levels; high missing-mass resolution (250 keV) coincidence experiments involving quasi-elastic knock-out processes, such as (e,e'rho) and (e,e'π) to investigate wave functions of individual nucleons in the nucleus; and photonuclear experiments, such as (γ,rho) and (γ,π), with the principal purpose to study pion-nucleus delta resonance effects in the final state of the reaction. This program is being carried out since 1981 with the 500 MeV electronscattering facility, featuring a beam handling system with high intrinsic resolution (≤5x10/sup -5/) and dispersion matching optics, a high resolution (≤ 1 x 10/sup -4/) QDD spectrometer for the detection of electrons, a large solid angle (17 msr) QDQ spectrometer for hadron detection, and detection systems consisting of multiwire drift chambers (0.25 mm spatial resolution), scintillators (timing resolution 0.5 ns) and Cerenkov counters. A survey of the on-going (e,e') experiments is given in this paper and special information is also given about the coincidence experiments which are carried out with a 2 % duty factor beam. Finally the plans of the Institute to increase the duty factor to 100 % is sketched