Experimental studies of inertial Alfvén-wave propagation through an Alfvén-speed gradient

Alfvén waves are ubiquitous in space, laboratory, and astrophysical plasmas. Understanding the reflection and transmission of these waves as they travel through plasma inhomogeneities is important for understanding wave propagation, turbulence, and heating of plasmas in general. Alfvén waves are predicted to reflect when encountering a gradient in the Alfvén speed. However, our recent studies using the Large Area Plasma Device (LAPD) at the University of California, Los Angeles, observed no reflection for kinetic Alfvén waves propagating through an Alfvén-speed gradient. In the present work, we have conducted LAPD experiments to study inertial Alfvén-wave propagation through an Alfvén-speed gradient. The gradients were created by varying the magnetic field in the direction of the propagation of the Alfvén wave. Here, we will present our results for the transmission and reflection of Alfvén waves along the Alfvén-speed gradient.