Prompt Fission Neutron Spectra Measurements From Neutron Induced Fission in ^239Pu And ^235U At Energies Below The Incident Neutron Energy
Abstract
Measurements of neutron induced fission neutron spectra (FNS) for ^235U and ^239Pu for energies below that of the incident neutron have been made at the University of Massachusetts Lowell Van de Graaff accelerator lab. The ^7Li(p,n)^7Be reaction produced 1.5 and 2.5 MeV neutrons used to induce fission in a 62 g ^235U sample and a 29 g ^239Pu sample. Measurements of FNS in this region are complicated by the fact that the accelerator produced incident neutrons are elastically and inelastically scattered from the sample with energies in the range of the fission neutrons. In order to enhance the detection of fission neutrons with respect to other neutron types we employed three fast BaF2 scintillation detectors near the scatterer to detect fission gamma rays in coincidence. The fission gamma-ray trigger was then used to gate a BC-501 liquid scintillation neutron detector for FNS acquisition.
- Publication:
-
APS Division of Nuclear Physics Meeting Abstracts
- Pub Date:
- October 1996
- Bibcode:
- 1996APS..DNP..AF11W