Beta Spectrum of Neutron Decay in Coincidence with Recoil Protons

摘要

It is shown that a precise measurement of the angular correlation coefficient 'a' yields theoretically important information about weak interactions. Different experimental approaches for the determination of this quantity were studied. The comparison between coincidence measurements and a determination and evaluation of the shape of the proton recoil spectrum led to the decision to choose the latter method. Detailed calculations were carried out on the precision to be expected from different types of proton spectrometers. Finally the following arrangement is chosen and its design discussed: A high vacuum tangential beam tube, accessible at both ends, is well suited as decay proton source for a precisely controlled spectrometry. It is planned to use a spherical condenser spectrometer and a specially developed low background detector for the postaccelerated protons. The beam hole at the opposite side of the reactor will be used for insertion of a test source for simulating decay protons to check the ion optical properties, transmission etc. between and during the spectrum measurements. (Author)