On alpha of 235U for sub-thermal neutron energies
An experiment to measure the capture to fission ratio alpha of 235U in the sub-thermal neutron energy region is described. The experiment was based on the measurement of specific low energy capture gamma-rays and prompt fission gamma-rays with a Ge detector. The liquid methane moderator of the Geel linac is used as a pulsed source of sub-thermal neutrons, the neutron energy being determined by time-of-flight. The method requires that the relative yields of the measured gamma-rays per capture and fission event do not vary over the energy range considered. Resultant alpha values show an increase by about 9% in the sub-thermal region as compared to thermal energy, corresponding to a 1.2% decrease in the number of fission neutrons emitted per neutron absorbed.
Bibliographic Reference: Paper presented: International Conference on Nuclear Data for Science and Technology, Jülich (DE), May 13-17, 1991
Availability: Available from (1) as Paper EN 36148 ORA
Record Number: 199110847 / Last updated on: 1994-12-02
Original language: en
Available languages: en