High-spin states in boson models with applications to actinide nuclei

Abstract

We use the 1/$N$ expansion formalism in a systematic study of high-spin states in the $sd$ and $sdg$ boson models with emphasis on spin dependence of moment of inertia and E2 transitions. The results are applied to the high-spin states in the actinide nuclei $^{232}$Th, $^{234-238}$U, where the need for $g$ bosons is especially acute but until now, no realistic calculation existed. We find that the $d$-boson energy plays a crucial role in description of the high-spin data.Comment: 11 pages Latex, 4 figures available upon request (to appear in Phys. Lett. B

Description of deformed nuclei in the sdg boson model

“…As mentioned in sect. 2, the minimal sdg-IBM Hamiltonian with quadrupole interaction and g-boson energy has previously been applied to deformed nuclei and found to be inadequate on most counts [12,14]. Inclusion of the d-boson energy and hexadecapole interaction appear to be necessary to improve this situation.…”

“…We discuss five such ratios as a function of q for various values of (a) η d = ε d /Nκ 2 and (b) which is the average value used in the applications. The g-boson energy has been found to have negligible effect [14], and therefore is not varied here but fixed at η g = 4.5. Below, we comment on the behaviour of each ratio and contrast them with the experimental data.…”

“…bands, and the yrast E2 transitions for each set of isotopes (figs [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27]…”

Cognitive perturbation through dynamic modelling: a pedagogical approach to conceptual change in science

“…The use of computer models to perform scientific investigations has played a vital role in advancing scientific research in areas of physical as well as biological science in the past decade (Kuyucak & Li 1995a, b; Li & Kuyucak 1996; Li et al . 1998).…”

Tests and applications of self-consistent cranking in the interacting boson model

“…To test more realistic Hamiltonians, we use the middle value for χ (− √ 7/4), which leads to a better description of electromagnetic properties [8]. Inclusion of the d-boson energy with ε = 1.5N κ improves, in addition, the moment of inertia systematics [9]. The exact energy eigenvalues E(L) are obtained from the Casimir operators in the case of the dynamical symmetries, and by numerical diagonalization of the Hamiltonian in the latter two cases.…”