High Resolution Solar Physics: Probing Elemental MHD Processes
Yukio Katsukawa

All the late type stars have the chromosphere and corona in the outer atmosphere whose temperatures are 10 to 1000 times hotter than the underlying photosphere. The energy required to sustain the temperatures is supplied by the interaction of turbulent convection with magnetic fields. The key question is how this kinetic and magnetic energy is transferred and converted into thermal energy. Recent progresses of high-resolution solar observations done with the HINODE satellite and ground-based telescopes have started resolving elemental MHD processes responsible for transferring and converting the magnetic energy in the solar outer atmosphere, such as acoustic and Alfvénic waves propagating through the atmosphere and spontaneous heating and supersonic flows driven by magnetic reconnection. These processes are relevant in various astrophysical plasmas, such as stellar coronae and flares, cosmic jets, and intergalactic plasmas over various spatial and energy scales. The next step is to obtain quantitative understanding of the processes by remotely sensing magnetic and velocity fields in the solar atmosphere. For it, precise measurements of polarization signals are demanded which is going to be attempted by the next-generation solar observations, especially by DKIST.