MEASUREMENT OF THE ANGULAR CORRELATION COEFFICIENT IN NEUTRON DECAY.
Abstract
The preparatory stages of an experiment to measure the angular correlation constant in a neutron beta decay are described. Neutrons will decay in the central part (next to the core) of a tangential beam tube of the ASTRA reactor. The decay protons fly over a distance of about 4 m into a spherical condenser electrostatic spectrometer and will finally be accelerated and counted by means of a coincidence ion-electron converter. A proton source at the other extreme of the beam tube will inject a precisely controlled beam of simulated decay protons at regular intervals, so that the constancy of transmission and of detection efficiency can be monitored in between spectrum measurements. The experiment requires low-background counting and the maintenance of low magnetic fields, low pressure and low electric fields under intense gamma and neutron irradiation. In preliminary investigations, the effect of neutron irradiation on soft magnetic materials, outgassing rates under reactor irradiation, and the effectiveness of magnetic shielding have been investigated. The shape of the proton spectrum, the influence of magnetic and electric fields upon the proton transmission, and corrections due to motion of the decay neutrons, and to finite spectrometer resolution, have been calculated. Most of the apparatus has been built.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 19, 1969
- Accession Number
- AD0685789
Entities
People
- Helmut Paul
- Peter Weinzierl