Determine whether Alfvénic polarization reflects genuine Alfvén-wave coupling

Determine whether the resistivity-dependent change in the polarization of slow magnetoacoustic pulsations, particularly their increasing electromagnetic component, should be interpreted as coupling to Alfvén waves in magnetically confined fusion plasmas.

Background

The simulations show that SMAPs are predominantly acoustic but acquire a weak electromagnetic or Alfvénic component whose relative strength changes with the resistivity and growth rate. The paper compares this behavior with studies of slow-wave instability in space plasmas that describe coupling between slow magnetoacoustic and Alfvén waves.

The authors caution that the terminology may not transfer directly to tokamak geometry and parameters. They therefore leave unresolved whether the observed polarization change represents physical Alfvén-wave coupling or a different form of mixed polarization intrinsic to the simulated quasi-mode.