Centrifugally induced curvature drift instability in AGN
  We investigate the centrifugally driven curvature drift instability to study
how field lines twist close to the light cylinder surface of an AGN, through
which the free motion of AGN winds can be monitored. By studying the dynamics
of the relativistic MHD flow close to the light cylinder surface, we derive and
solve analytically the dispersion relation of the instability by applying a
single particle approach based on the centrifugal acceleration. Considering the
typical values of AGN winds, it is shown that the timescale of the curvature
drift instability is far less than the accretion process timescale, indicating
that the present instability is very efficient and might strongly influence
processes in AGN plasmas.
