  We study collective excitations in systems described by chiral kinetic theory
in external magnetic field. We consider high-temperature weak-coupling plasma,
as well as high-density Landau Fermi liquid with interaction not restricted to
be weak. We show that chiral magnetic wave (CMW) emerges in hydrodynamic regime
(at frequencies smaller than collision relaxation rate) and the CMW velocity is
determined by thermodynamic properties only. We find that in a plasma of
opposite chiralities, at frequencies smaller than the chirality-flipping rate,
the CMW excitation turns into a vector-like diffusion mode. In the interacting
Fermi liquid, the CMW turns into the Landau zero sound mode in the
high-frequency collisionless regime.
