Chiral basis for particle-rotor model for odd-odd triaxial nuclei

In the last decade nuclear chirality resulting from an orthogonal coupling of angular momentum vectors in triaxial nuclei has been a subject of numerous experimental and theoretical studies. Three perpendicular angular momenta can form two systems of the opposite handedness, the right-handed and the left-handed system; the time-reversal operator, which reverses orientation of each of the components, relates these two systems. In the simplest case of odd-odd nuclei, two mutually orthogonal angular momenta are provided by the high-spin valence proton and neutron which are of particle and hole character. The third angular momentum component is provided by the collective core rotation and aligns along the axis of the largest moment of inertia; this is the intermediate axis for irrotational flow-like moments of inertia for a triaxial body. This simple picture leads to prediction of distinct observables manifesting chirality in rotational structures, most notably to the doubling of states. All these effects can be demonstrated using particle-rotor model for triaxial nuclei, and are especially transparent when a newly developed chiral basis is used in calculations. The model, the basis, numerical results, and comparison to the data will be presented and discussed.