D (e, e'p) Coincidence Experiment at Low Energy and High Momentum Transfer.

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Inthis experiment, the angular distributions of protons are measured in coincidence with the scattered electrons near the threshold of the deuteron at high momentum transfer. According to the preliminary theoretical calculations, it is expected that the meson exchange currents and the relativistic effects are important in this experiment. This experiment needs a liquid-deuterium target and a reliable detector system.At the MIT-Bates laboratory, a round target chamber is usually used. However, because the energy loss of the proton through the round target is dependent of the reaction point, the proton energy spectrum is spread by 5 MeV.The energy loss should be constant independent of the reaction point to satisfy the energy resolution the experiment demands. We have chosen a recutangular target chamber in order to keep the path length of the protons in the target constant. Contrary to the round target, the stress to materials is not unform for the recutangular chamber. The chamber have … More to be carefully designed because the deuterium is an explosive. Several trial chambers constructed in Japan were tested to prove its reliability and safety in University of Massachusetts in USA.The data of the test were used when a practical chamber was constructed.In this experiment, scattered electrons and emitted protons are analyzed with two magnetic spectrometers. The angle of the proton has to be measured with a resolution better than 20 mr at the target. In the forcal plane of the spectrometers, the detector system is installed, consisting of vertical drift chambers which measure the position and angle of the particles, scintillation counters which create timing signals, an Aerogel Cherenkov counter which separates electrons from other particles. The design values of the system satisfy the demanded performance for the experiment. However they have to be confirmed from the actual experiments, because there may exist errors out of consideration. We therefore evaluated the effects of the corrections and the final resolution using data of the ^3He (e, ed) experiment. It has been shown that the final results satisfy the performance our experiment demands. Less