Dynamic Structure Function in a Strongly Magnetized High Energy Density Plasma

Strongly magnetized plasmas are characterized by having an electron gyroradius that is significantly smaller than the Debye length. This is a novel regime for plasma kinetic theory because electrons gyrate within the collision volume where interactions between particles take place. Recent work has developed new kinetic theories for strongly magnetized plasmas from linear response approaches as well as Boltzmann equation-based approaches. Here, we apply these recent advances to compute the dynamic structure function in a strongly magnetized plasma. We focus on the magnetohydrodynamic (MHD) regime. The model starts by developing generalized MHD equations for strongly magnetized plasmas. These have the same structure as standard MHD, but where the coefficients in the transport tensors are computed from a generalized collision operator of the new kinetic theory. These MHD equations are linearized and solved for the linear response function which provides the dynamic structure function in the hydrodynamic limit (long wavelength and low frequency). The predictions may be useful for interpreting scattering measurements in future magnetized HEDP experiments.