Impact of the toroidal rotation on the n dependence of the growth rate of the edge localized MHD modes

In this paper, we investigate the dependence of the stability of the edge localized MHD mode on the toroidal mode number n with the MINERVA code. Unlike in the static case, the sheared toroidal rotation can induce the non-exponential growth of the MHD instability, and the growth rate oscillates in time. This oscillation is excited by the beat between two unstable eigenmodes whose growth rates are almost identical to but frequencies are different from each other. Due to the declination of the plasma rotation frequency at the peak of the envelope of the eigenmode structure, the frequencies of the eigenmodes become different from each other. The reason that makes such a difference of the peak position of the envelope is still under discussion, but this will come from the difference between the position where the ballooning mode can have the largest growth rate and that where the rotation can change the MHD stability effectively. This will be investigated and will be reported in near future.