  The static quadrupole moments (SQMs) of nuclear chiral doublet bands are
investigated for the first time taking the particle-hole configuration
$\pi(1h_{11/2}) \otimes \nu(1h_{11/2})^{-1}$ with triaxial deformation
parameters in the range $260^\circ \leq \gamma \leq 270^\circ$ as examples. The
behavior of the SQM as a function of spin $I$ is illustrated by analyzing the
components of the total angular momentum. 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 $\cos\gamma$ for both doublet bands. This provides a way to
extract experimentally the triaxial deformation parameter $\gamma$ for chiral
bands from the measured SQMs.
