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arXiv · 0807.4447

Exactly separable version of the Bohr Hamiltonian with the Davidson potential

Dennis Bonatsos·E. A. McCutchan·N. Minkov·R. F. Casten·P. Yotov·D. Lenis·D. Petrellis·I. Yigitoglu
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Abstract

An exactly separable version of the Bohr Hamiltonian is developed using a potential of the form u(beta)+u(gamma)/beta^2, with the Davidson potential u(beta)= beta^2 + beta_0^4/beta^2 (where beta_0 is the position of the minimum) and a stiff harmonic oscillator for u(gamma) centered at gamma=0. In the resulting solution, called exactly separable Davidson (ES-D), the ground state band, gamma band and 0_2^+ band are all treated on an equal footing. The bandheads, energy spacings within bands, and a number of interband and intraband B(E2) transition rates are well reproduced for almost all well-deformed rare earth and actinide nuclei using two parameters (beta_0, gamma stiffness). Insights regarding the recently found correlation between gamma stiffness and the gamma-bandhead energy, as well as the long standing problem of producing a level scheme with Interacting Boson Approximation SU(3) degeneracies from the Bohr Hamiltonian, are also obtained.

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Dennis Bonatsos, E. A. McCutchan, N. Minkov, R. F. Casten, P. Yotov, D. Lenis, D. Petrellis, I. Yigitoglu. 2008-07-28. Exactly separable version of the Bohr Hamiltonian with the Davidson potential. https://doi.org/10.1103/physrevc.76.064312

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