Prolate - oblate phase transition in the Hf - Hg mass region

Experimental data in the Hf-Hg mass region indicate the presence of a prolate-oblate phase transition. The transition in which $\ensuremath{\gamma}$-soft nuclei exhibit a first-order quantum phase transition in their shape is of the type that was recently proposed on very general grounds using Landau theory. The transition is situated close to the O(6) limit of the interacting boson model which is indeed found empirically in this mass region. Our study also hints at explaining why the quadrupole moments in Pt isotopes deviate from the O(6) value and confirms the recently proposed prolate-oblate phase transition with experimental data.

[1]  D. Warner.  Nuclear physics: A triple point in nuclei , 2002, Nature.

[2]  S. Heinze,et al.  Triple point of nuclear deformations. , 2002, Physical review letters.

[3]  R. Casten,et al.  Quantum phase transition for gamma-soft nuclei. , 2001, Physical review letters.

[4]  R. Casten,et al.  Quantum Phase Transition for γ -Soft Nuclei , 2001 .

[5]  R. Casten,et al.  Empirical realization of a critical point description in atomic nuclei. , 2001, Physical review letters.

[6]  F. Iachello.  Analytic description of critical point nuclei in a spherical-axially deformed shape phase transition. , 2001, Physical review letters.

[7]  Iachello.  Dynamic symmetries at the critical point , 2000, Physical review letters.

[8]  Zamfir,et al.  Evidence for a possible E(5) symmetry in 134Ba , 2000, Physical review letters.

[9]  Jolie,et al.  Quantum phase transitions studied within the interacting boson model , 2000, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics.

[10]  A. N. Andreyev,et al.  A triplet of differently shaped spin-zero states in the atomic nucleus 186Pb , 2000, Nature.

[11]  Z. Chunmei,et al.  Regular ArticleNuclear Data Sheets for A = 196☆ , 1998 .

[12]  M. Schmorak.  Nuclear Data Sheets Update for A = 200 , 1995 .

[13]  Z. Chunmei.  Nuclear Data Sheets Update for A = 198 , 1995 .

[14]  E. Browne.  Nuclear Data Sheets Update for A = 180 , 1994 .

[15]  Boerner,et al.  First measurement of B(E2) values from sigma , 1990, Physical review. C, Nuclear physics.

[16]  W. Nazarewicz,et al.  Evidence for a change of structure in the heavy mercury isotopes around 200Hg , 1990 .

[17]  R. Firestone.  Nuclear data sheets for A = 184 , 1989 .

[18]  R. Firestone.  Nuclear data sheets for A = 186 , 1988 .

[19]  R. Casten,et al.  196Pt - still an O(6) nucleus , 1987 .

[20]  R. Casten,et al.  Predictions of the interacting boson approximation in a consistent Q framework , 1983 .

[21]  O. Scholten,et al.  Classical Limit of the Interacting-Boson Model , 1980 .

[22]  J. Cizewski,et al.  The O(6) → rotor transition in the PtOs nuclei , 1978 .

[23]  H. Börner,et al.  Evidence for a New Symmetry in Nuclei: The Structure of Pt 196 and the O(6) Limit , 1978 .