Static quadrupole moments of nuclear chiral doublet bands

The static quadrupole moments (SQMs) of nuclear chiral doublet bands are investigated for the first time taking the particle-hole configuration π(1h_11/2)⊗ν(1h_11/2)⁻¹ with triaxial deformation parameters in the range 260^∘≤γ≤270^∘ as examples. The behavior of the SQM as a function of spin I is illustrated and analyzed. It is found that in the region of chiral vibrations the SQMs of doublet bands are strongly varying with I, whereas in the region of static chirality the SQMs of doublet bands are almost constant. Hence, the measurement of SQMs provides a new criterion for distinguishing the modes of nuclear chirality. Moreover, in the high-spin region the SQMs can be approximated by an analytic formula with a proportionality to cos⁡γ for both doublet bands. This provides a way to extract experimentally the triaxial deformation parameter γ for chiral bands from the measured SQMs.