Delayed neutron emission measurements for U-235 and Pu-239
Abstract
The delayed neutron emission rates of U-235 and Pu-239 samples were measured
accurately from a thermal fission reaction. A Monte Carlo calculation using the Geant4
code was used to demonstrate the neutron energy independence of the detector used in the
counting station.
A set of highly purified actinide samples (U-235 and Pu-239) was irradiated in these
experiments by using the Texas A&M University Nuclear Science Center Reactor. A fast
pneumatic transfer system, an integrated computer control system, and a
graphite-moderated counting system were constructed to perform all these experiments.
The calculated values for the five-group U-235 delayed neutron parameters and the
six-group Pu-239 delayed neutron parameters were compared with the values
recommended by Keepin et al. (1957) and Waldo et al. (1981). These new values differ
slightly from literature values. The graphite-moderated counting station and the
computerized pneumatic system are now operational for further delayed neutron
measurement.
Citation
Chen, Yong (2006). Delayed neutron emission measurements for U-235 and Pu-239. Master's thesis, Texas A&M University. Available electronically from https : / /hdl .handle .net /1969 .1 /ETD -TAMU -1134.