Alfvén QPOs in magnetars in the anelastic approximation

  title={Alfv{\'e}n QPOs in magnetars in the anelastic approximation},
  author={Pablo Cerd{\'a}-Dur{\'a}n and Nikolaos Stergioulas and Jos{\'e} A. Font},
We perform two-dimensional simulations of Alfven oscillations in magnetars, modeled as relativistic stars with a dipolar magnetic field. We use the a nelastic approximation to general relativistic magnetohydrodynamics, which allows for an effective suppression of fluid modes and an accurate description of Alfven waves. In addition, we compute Alfven oscillation fre- quencies along individual magnetic field lines with a semi-a nalytic approach, employing a short-wavelength approximation. Our… 

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