9:15 AM - 9:30 AM
[PEM16-02] Dependence on the background magnetic field of ion Weibel instability
Keywords:Collisionless shocks, Weibel instability, Cosmic ray
We discuss the ion beam instability in the case of a moderate background magnetic field in the sense that the timescale of the instability is shorter than the ion gyro period but longer than the electron gyro period. It is to be noted that a typical young supernova remnant parameter lies in this category. We performed 2D particle-in-cell simulation in various parameters.
We found that the magnetized electrons in the moderate background magnetic field case can amplify the magnetic field further compared to the unmagnetized case, and the amplified magnetic field can cause turbulent structure after magnetic reconnection and Kelvin Helmholtz like instability. Electron heating is also the most efficient in the moderately magnetized case.
[1] T. Nishigai and T. Amano, "Mach number dependence of ion-scale kinetic instability at collisionless perpendicular shock: Condition for Weibel-dominated shock", Physics of Plasmas 28, 072903 (2021)