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"Beat" patterns for the odd-even staggering in octupole bands from a quadrupole-octupole Hamiltonian

N. Minkov·S. B. Drenska·P. P. Raychev·R. P. Roussev·D. Bonatsos
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Abstract

We propose a collective Hamiltonian which incorporates the standard quadrupole terms, octupole terms classified according to the irreducible representations of the octahedron group, a quadrupole-octupole interaction, as well as a term for the bandhead energy linear in K (the projection of angular momentum on the body-fixed z-axis). The energy is subsequently minimized with respect to K for each given value of the angular momentum I, resulting in K values increasing with I within each band, even in the case in which K is restricted to a set of microscopically plausible values. We demonstrate that this Hamiltonian is able to reproduce a variety of ``beat'' patterns observed recently for the odd-even staggering in octupole bands of light actinides.

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N. Minkov, S. B. Drenska, P. P. Raychev, R. P. Roussev, D. Bonatsos. 2001-06-05. "Beat" patterns for the odd-even staggering in octupole bands from a quadrupole-octupole Hamiltonian. https://doi.org/10.1103/physrevc.63.044305

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