Artigo Acesso aberto

Parity restoration in the highly truncated diagonalization approach: Application to the outer fission barrier of 240 Pu

2012; American Institute of Physics; Volume: 86; Issue: 6 Linguagem: Inglês

10.1103/physrevc.86.064307

ISSN

1538-4497

Autores

T. V. Nhan Hao, P. Quentin, L. Bonneau,

Tópico(s)

Rare-earth and actinide compounds

Resumo

The restoration of the parity symmetry has been performed in the framework of the Highly Truncated Diagonalization Approach suited to treat correlations in an explicitly particle-number conserving microscopic approach. To do so we have assumed axial symmetry and used a generalized Wick's theorem due to L\"owdin in a projection-after-variation scheme. We have chosen the Skyrme SkM$^*$ energy-density functional for the particle-hole channel and a density-independent delta force for the residual interaction. We have applied this approach in the region of the outer fission barrier of the $^{240}$Pu nucleus. As a result, we have shown that the $K^{\pi} = 0^+$ fission isomeric state is statically unstable against intrinsic-parity breaking modes, while the projection does not affect the energy at the top of the intrinsic outer fission barrier. Altogether, this leads to an increase of the height of the outer fission barrier--with respect to the fission isomeric state--by about 350 keV, affecting thus significantly the fission-decay lifetime of the considered fission isomer.

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