A Landau fluid model for warm collisionless plasmas

A Landau fluid model for a collisionless electron-proton magnetized plasma that accurately reproduces the dispersion relation and the Landau damping rate of all the magnetohydrodynamic waves is presented. It is obtained by an accurate closure of the hydrodynamic hierarchy at the level of the fourth-order moments, based on linear kinetic theory. It retains nongyrotropic corrections to the pressure and heat flux tensors up to the second order in the ratio between the considered frequencies and the ion cyclotron frequency.