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Register a new userThe Structure of Plasma Heating in Gyrokinetic Alfvenic Turbulence
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Added by
Alejandro Ba\\~n\\'on Navarro
Publication date
2016
fields
Physics
and research's language is
English
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We analyze plasma heating in weakly collisional kinetic Alfven wave (KAW) turbulence using high resolution gyrokinetic simulations spanning the range of scales between the ion and the electron gyroradii. Real space structures that have a higher than average heating rate are shown not to be confined to current sheets. This novel result is at odds with previous studies, which use the electromagnetic work in the local electron fluid frame, i.e. $mathbf{J} !cdot! (mathbf{E} + mathbf{v}_etimesmathbf{B})$, as a proxy for turbulent dissipation to argue that heating follows the intermittent spatial structure of the electric current. Furthermore, we show that electrons are dominated by parallel heating while the ions prefer the perpendicular heating route. We comment on the implications of the results presented here.
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