Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Iwamoto, Akira; M
ller, P.*; Madland, D. G.*; Sierk, A.*
Journal of Nuclear Science and Technology, 39(4), p.332 - 336, 2002/04
Times Cited Count：2 Percentile：16.96(Nuclear Science & Technology)The theoretical calculations on the most probable mass division in nuclear fission process are given. The model is based on the topographical analysis of the five-dimensional potential energy surface of more than 2.5 million mesh points. Special attention is paid to obtain the energies and deformations of the saddle points without using any approximation. The calculation tells us that there exist multiple saddle points in the static potential energy surface. The lowest and the next lowest saddle point play an important role for the fission process. Of these two saddle points, one is mass-symmetrically deformed and the other is mass-asymmetrically deformed and the relative heights of these two saddle points depend on the fissioning nuclei. In case of Fm isotopes, the relative height of two saddle points appears very sensitively, i.e., 
Fm has asymmetrically deformed lowest saddle point and in 
Fm, the lowest saddle point is symmetrically deformed. This feature explains the phenomenon called bimodal fission.
Mller, P.*; Madland, D. G.*; Sierk, A. J.*; Iwamoto, Akira
Nature, 409(6822), p.785 - 789, 2001/02
Times Cited Count：287 Percentile：99.33(Multidisciplinary Sciences)no abstracts in English
Iwamoto, Akira; Mller, P.*; Madland, D. G.*; Sierk, A. J.*
AIP Conference Proceedings 597, p.243 - 248, 2001/00
We present calculations of fission potential energy surface based on Strutinsky's prescription for realistic shape parameterization of the fissioning nuclei. It involves 5 shape parameters from which we obtain 5-dimensional potential energy surface of more than 2.5 million points. The analysis of the saddle point was performed without any approximation and we obtained the following understanding of the fission process. (1) Most of the actinide nuclei have the lowest two saddle points, one is mass-symmetric and the other is mass-asymmetric. (2) The relative height of these two saddles depends on the fissioning nucleus and experimentally observed mass division mode was well understood from the properties of the lowest saddle point. (3) Bimodal feature of Fm isotopes was well understood from the analysis of the saddle points. (4) Degree of the mass asymmetry of the most probable mass division was well understood from the potential energy surface.
