Alfvénic waves are prevalent throughout the solar atmosphere and are believed to play an essential role in coronal heating, classified as alternating current (AC) heating in contrast to direct current (DC) heating associated with quasi-static magnetic field line braiding. The relative importance of AC versus DC heating depends on the details of the photospheric driver and the magnetic-field configuration. Moreover, even if AC heating prevails, several wave dissipation mechanisms have been proposed, and which of them dominates remains unclear, as their efficiency depends on plasma compressibility and density inhomogeneity. We address these issues by performing three-dimensional radiative magnetohydrodynamic (MHD) simulations of a coronal loop spanning from the upper convection zone to the corona, which self-consistently capture many relevant physical processes. We find that the corona is predominantly heated by AC heating, with Alfvén wave turbulence providing the primary contribution and accounting for at least 80% of coronal heating in the present simulation. Our results strongly support Alfvén wave turbulence-based models used in space weather and stellar activity research, such as the Alfvén Wave Solar Model (AWSoM) and the Magnetohydrodynamic Algorithm outside a Sphere (MAS). Speaker: Hidetaka Kuniyoshi
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