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Relation between the critical spin and angular velocity of a nucleus immediately after backbending

V. G. Nosov·A. M. Kamchatnov
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Abstract

In nonspherical nuclei at $J = J_c + 0$ the relationship between the angular momentum and angular velocity immediately after backbending is the same as in the limiting case $J - J_c\to\infty$. This indicates that there is a unique type of cancellation of the deviations from a rigid-body moment of inertia in the upper phase $J>J_c$. An integral relationship is found which expresses this cancellation quantitatively. This formula permits $J_c$ to be calculated for the rotational bands of the even-even nuclei studied and the results are in agreement with those obtained by other methods of locating the Curie point. For the ground state band of W$^{170}$ the cancellation of the reciprocals of the true and rigid-body moments of inertia can be verified directly. The condition for the stability of the rotation of a nonspherical nucleus is analyzed in the Appendix in close connection with the problem of a reasonable definition of the concept of a variable moment of inertia.

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V. G. Nosov, A. M. Kamchatnov. 2004-05-01. Relation between the critical spin and angular velocity of a nucleus immediately after backbending. https://arxiv.org/abs/nucl-th/0405001

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