Open Access
ND 2007
Article Number 082
Number of page(s) 4
Section Evaluation of covariance matrices
Published online 17 June 2008
International Conference on Nuclear Data for Science and Technology 2007
DOI: 10.1051/ndata:07728

Systematics and uncertainties of Hamiltonian parameters of soft-rotator model for actinides and their implications for nuclear data calculations

S. Chiba1, H. Koura1, T. Maruyama1, S. Kunieda1 and E. Sh. Soukhovitskii2

1  Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195, Japan
2  Joint Institute for Energy and Nuclear Research, 220109 Minsk-Sosny, Beralus

Published online: 21 May 2008

The collective low-lying levels of even-even actinides are analyzed in terms of the soft-rotator model (SRM), and best fit parameters of SRM Hamiltonian are deduced for 19 nuclides. Systematics of these parameters are then obtained as a function of the ground-state quadrupole deformation. It was found that there is a possibility of extending such a systematics to include the fission product nuclei. Furthermore, we propose a method to estimate the covariance of the SRM parameters and its impact on the cross sections calculated with them quantitatively. It is shown that low-energy observables are more sensitive to the uncertainties in the SRM parameters, therefore, sensitive to the collective structure effects.

© CEA 2008