*Hayato Higuchi1, Akimasa Yoshikawa2
(1.Department of Earth and Planetary Sciences, Graduate School of Science, Kyushu University, 2.Department of Earth and Planetary Sciences, Faculty of Science, Kyushu University)
Keywords:Poleward Boundary Intensification, Auroral electron acceleration mechanism, Kinetic effect, Vlasov simulation, M-I coupling system, Wave particle interaction
The auroral oval poleward boundary auroral intensification (PBI) had been regarded the result of “distant neutral line reconnection” effects in the ionosphere. On the other hand, Ohtani and Yoshikawa., [2016] proposed a model in which PBI is the result of polarization process caused by plasma flows due to “dayside reconnection” approaching the conductivity gradient region of auroral oval. This model is an application of the theory of ionospheric polarization-field-aligned current (FAC) proposed by Yoshikawa et al., [2013]. According to Ohtani and Yoshikawa., [2016], Alfven waves upwelling from the ionosphere to the magnetosphere accelerate electrons downward and generating explosive auroral intensification. This is a new concept of the auroral process that has never existed in magnetospheric physics before. To simulate above mentioned process, it is essential to consider the ionosphere-magnetosphere coupling via Alfven waves and kinetic effects based on wave-particle interactions, which can explain "how upward Alfven waves rising from the cold ionosphere as a result of ionospheric polarization can trigger explosive downward electron acceleration?.”
In this research, in order to reproduce the aurora acceleration process associated with "ionospheric polarization PBI", we try to develop a "3D Vlasov-PIC-Fluid electron acceleration simulation". This simulation scheme has advantages such as maximum kinetic effect and reduced computational cost in reproducing the electron acceleration process by Alfven waves of ionospheric origin.
In this presentation, we will introduce new model of PBI, and explain basic concept of our developing Vlasov-PIC-Fluid code.