Pseudospin symmetry and octupole correlations for multiple chiral doublets in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mmultiscripts><mml:mi>Ba</mml:mi><mml:mprescripts/><mml:none/><mml:mn>131</mml:mn></mml:mmultiscripts></mml:math>
Yiping Wang, Y. Y. Wang, Jie Meng
Abstract
A reflection-asymmetric triaxial particle rotor model with three quasiparticles and a reflection-asymmetric triaxial rotor is developed, and applied to investigate the observed multiple chiral doublets $(\mathrm{M}\ensuremath{\chi}\mathrm{D})$ candidates with octupole correlations in $^{131}\mathrm{Ba}$, i.e., two pairs of positive-parity bands D3-D4 and D5-D6, as well as one pair of negative-parity bands D7-D8. The energy spectra, the energy staggering parameters, the $B(M1)/B(E2)$ ratios, and the $B(E1)/B(E2)$ ratios are reproduced well. The chiral geometries for these $\mathrm{M}\ensuremath{\chi}\mathrm{D}$ candidates are examined by the azimuthal plots, and the evolution of chiral geometry with spin is clearly demonstrated. The intrinsic structure for the positive-parity bands is analyzed and the possible pseudospin-chiral quartet bands are suggested.