  The quark-gluon plasma (QGP) generated in relativistic heavy-ion collisions
could be locally parity-odd. In parity-odd QGP, the electric field may induce a
chiral current which is called the chiral electric separation effect (CESE). We
propose two possible observables for CESE in Cu + Au collisions: The first one
is the correlation $\zeta_{\alpha\beta}=\langle
\cos[2(\phi_\alpha+\phi_\beta-2\Psi_{\rm RP})]\rangle$; the second one is the
charge-dependent event-plane angle $\Psi^{q}_2$ with $q=\pm$ being charge.
Nonzero $\Delta\zeta=\zeta_{opp}-\zeta_{same}$ and
$\Delta\Psi=\langle|\Psi_2^+-\Psi_2^-|\rangle$ may signal the CESE in Cu + Au
collisions. Within a multiphase transport model, we study how the final state
interaction affects these observables. We find that the correlation
$\gamma_{\alpha\beta}=\langle\cos(\phi_{\alpha}+\phi_{\beta}-\Psi_{\rm
RP})\rangle$ is sensitive to the out-of-plane charge separation caused by the
chiral magnetic effect and to the in-plane charge separation caused by the
in-plane electric field, but it is not sensitive to the CESE. On the other
hand, $\Delta\zeta$ and $\Delta\Psi$ are sensitive to the CESE. Therefore, we
suggest that the future experiments measure the above observables in Cu+Au
collisions in order to disentangle different chiral and charge separation
mechanisms.
