Group theory and nuclear high spin phenomena
A microscopic interpretation of the coherent/critical phenomenon known as backbending, in which certain deformed nuclei, looked upon as rotating spheriods, show a marked increase in their effective moment of inertia at some critical value of the total angular momentum, is presented. As shell-model calculations in a basis constructed from a direct product of single-particle orbitals leads to matrix dimensionalities that are enormous, truncation is required. The complementary roles group theory and methods of statistical spectroscopy play in the selection of a physically significant coupling scheme are illustrated. A weak coupling model of the normal and abnormal parity orbitals organized into SU(3) and R(5) multiplets, respectively, shows pair alignment to be the primary mechanism responsible for backbending but band mixing can be competitive and lead to anomalous E2 behavior. Results for 126Ba are given.
KeywordsTotal Angular Momentum Effective Moment High Weight State Yrast Band Yrast State
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- 1.A. Bohr and B. R. Mottelson, in Proceedings of the International Conference on Nuclear Structure, edited by T. Marumori (Japan, 1977) J. Phys. Soc. Japan 44, Suppl. 157 (1978).Google Scholar
- 4.Alan L. Goodman, in Advances in Nuclear Physics, Vol. 11, edited by J. W. Nagele and Erich Vogt (Plenum, New York, 1978).Google Scholar
- 13.J. P. Schiffer, in Two-Body Forces in Nuclei, edited by S. M. Austin and G. M. Crawley (Plenum, New York, 1972).Google Scholar