Alfv\'{e}n Wave Propagation in Strongly Inhomogeneous Partially Ionized Plasmas in the \textit{Hot hELicon eXperiment (HELIX)}

Alfv\'{e}n wave damping is one of the most important mechanisms for understanding ion heating in the solar corona. The presence of ion-neutral collisions in partially ionized plasmas, such as the chromosphere, has a significant but not well-understood effect on Alfv\'{e}n wave propagation and energy transfer. Since the neutral density in HELIX varies strongly with radius, a wide range of Alfv\'{e}n dynamics can be studied across the plasma column and the effects of changing the ion-neutral collision frequency can be observed. The ratio of the ion-neutral collision frequency to the ion-cyclotron frequency in HELIX varies from about 0.02 to 0.5 across the plasma column. In the solar atmosphere this ratio varies from approximately 10$^{-6}$ to 10.$^{ }$ With the use of a low-frequency wave-launching antenna and a small-scale (smaller than the ion gyroradius) magnetic sense coil probe, the behavior of radially confined Alfv\'{e}n waves is measured and characterized. These observations, coupled with LIF measurements of the plasma temperature and drift, are compared to observations in the corona.