CODE NUCLIDE ORIGINAL DATA TAKEN FROM MODIFICATION ADDITIONAL FILE MODIFICATIONS ORIGINAL DATA TAKEN FROM MODIFICATION ADDITIONAL FILE MODIFICATIONS COMMENTS
1093237 093_Np_237 ENDF/B-VI.8 Covariances - BNL, July, 2011: Covariances were adopted from
COMMARA-2.0, which were contributed by BNL. S. Mughabghab
produced revisited low-fidelity estimates at low energies.
In the fast neutron region cross section covariances were obtained
using EMPIRE/KALMAN approach (M. Pigni, BNL), with prior
parameterization produced by Mihaela Sin (Bucharest). Three
nuclear reaction models were adopted: (i) coupled-channels
optical model (RIPL catalog number 2408), (ii) Hauser-Feshbach
statistical model, and (iii) exciton pre-equilibrium model.
Optical model allowed us to determine total and absorption cross
sections, neutron direct elastic and inelastic scattering, as
well as the transmission coefficients needed to calculate the
compound-nucleus cross sections. Coupled-channels (CC)
calculations were performed using five collective levels and
three deformation parameters. For Hauser-Feshbach part of
calculations adopted were EMPIRE-specific level densities. The
treatment of the fission channel was carried out within the
formalism developed by M. Sin. We varied inner and outer barrier
heights and widths for the fissioning nuclei. MATP SEt to zero in MF8/MT16 at NNDC