Semianalytical calculation of the zonal-flow oscillation frequency in stellarators

  title={Semianalytical calculation of the zonal-flow oscillation frequency in stellarators},
  author={P. Monreal and E. S{\'a}nchez and Iv{\'a}n Calvo and A. Bustos and Felix I. Parra and Alexey Mishchenko and Axel Konies and Ralf Kleiber},
  journal={Plasma Physics and Controlled Fusion},
Due to their capability to reduce turbulent transport in magnetized plasmas, understanding the dynamics of zonal flows is an important problem in the fusion program. Since the pioneering work by Rosenbluth and Hinton in axisymmetric tokamaks, it is known that studying the linear and collisionless relaxation of zonal flow perturbations gives valuable information and physical insight. Recently, the problem has been investigated in stellarators and it has been found that in these devices the… 

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where Z ̂ is the plasma dispersion function of ̂ R0q /vTi and DS ̂ Ti /Te+1+ ̂Z ̂ is used. The FOW effect on the GAM dispersion relation 1/KGAM =0 is included in Eq. 14 through the function JFOW