Japan Geoscience Union Meeting 2016

Presentation information


Symbol P (Space and Planetary Sciences) » P-EM Solar-Terrestrial Sciences, Space Electromagnetism & Space Environment

[P-EM17] Space Plasma Physics: Theory and Simulation

Wed. May 25, 2016 9:00 AM - 10:30 AM 302 (3F)

Convener:*Takayuki Umeda(Institute for Space-Earth Environmental Research, Nagoya University), Takanobu Amano(Department of Earth and Planetary Science, University of Tokyo), Yasuhiro Nariyuki(Faculty of Human Development, University of Toyama), Tadas Nakamura(Fukui Prefectural University), Tooru Sugiyama(Japan Agency for Marine-Earth Science and Technology Center for Earth Information Science and Technology), Chair:Yasuhiro Nariyuki(Faculty of Human Development, University of Toyama), Shinji Saito(Graduate School of Science, Nagoya University)

9:30 AM - 9:45 AM

[PEM17-15] Moment extracted method for solving kinetic Alfven wave dynamics

*Tomo-Hiko Watanabe1, Yusuke Watanabe1, Shinya Maeyama1 (1.Graduate School of Science, Nagoya University)

Keywords:Alfven waves, simulation, gyrokinetics

Kinetic Alfven waves (KAW), which play crucial roles in a variety of phenomena in space plasmas, involve multiple space- and time-scales. For example, the wavelength along the field line may extend to the system size, while the perpendicular wave numbers are characterized by the ion gyro-radius or the electron skin depth. The characteristic time is given the wave frequency or the electron transit time. Thus, drift kinetic or gyrokinetic simulations of low-frequency plasma dynamics including the KAWs often suffer from a sever Courant condition for explicit time-integrators or a poor convergence of iteration in implicit methods.
To overcome the numerical inefficiency, we have developed a new scheme for solving the KAW dynamics including drift kinetic electrons. In the new scheme, the low-order moments of electron distribution function are calculated separately from the drift kinetic equation for electrons. It enables us to easily implement implicit time-integrators and/or the semi-Lagrangian scheme while keeping the numerical stability and the conservation property. Some applications of the moment extracted formulation will be discussed.