Authors: Michael Hahn (Columbia University), Xiangrong Fu (Los Alamos National Laboratory), Stefan J. Hofmeister (Columbia University), Yifan Huang (University of Alabama), Alexandros Koukras (Columbia University), Daniel Wolf Savin (Columbia University)

Some wave-driven models of coronal heating hypothesize that interactions between Alfvenic waves and density fluctuations enhance the rate of turbulent dissipation and thereby increase the efficiency of Alfvenic wave heating. Such interactions may include reflection from density fluctuations that Alfven waves encounter as they propagate or nonlinear wave interactions such as the parametric decay instability. Here, we survey the properties of Alfvenic waves and density fluctuations in the quiet corona using data from the Coronal Multichannel Polarimeter (COMP) and the Daniel K Inouye Solar Telescope (DKIST) and search for signatures of these interactions. Alfvenic waves are observed through the Doppler shifts in emission line centroids and density fluctuations through variations in the line intensity. We describe the power spectra, perpendicular length scales, propagation speeds, phase relationships, and other properties of these fluctuations. We find that Doppler velocity fluctuations are clearly related to Alfvenic waves, but that density fluctuations come from a variety of sources including multiple wave modes and other aperiodic variations. We also find that the characteristics of the interactions between density and velocity fluctuations differ between relatively short ~100 Mm closed loops versus long streamer loops. One interpretation is that long loops rely on reflection and instabilities to drive turbulence and heating similar what is expected for open field lines, whereas short loops have strong interactions between waves excited from opposite footpoints.