Speaker
Description
An effort is now underway to produce a new evaluation of the neutron cross section standards.
It is important to maintain experimental programs to increase the quality and extend the database
for the neutron cross section standards in order to improve evaluations of them that will be used to convert cross section measurements made relative to those standards.
Measurements have been made for most of the standard cross sections since the last evaluation of the standards. The improved database includes the cross sections for the H(n,n), $^6$Li(n,t),$^{10}$B(n,αγ),
$^{10}$B(n,α), C(n,n), Au(n,γ), $^{235}$U(n,f) and $^{238}$U(n,f) standard reactions and ratios among them. The database also includes the $^{238}$U(n,γ) and $^{239}$Pu(n,f) cross sections in addition to the standard cross sections. Those data were included since there are many ratio measurements of those cross sections with the standards and absolute data are available on them. Thus they will have an impact on the standards in the evaluation process that includes ratio data. In addition to the standard cross section measurements, work has been done and is ongoing on nubar for $^{252}$Cf.
The results obtained from the work on this project will be given at this meeting.