Strong reconnection electric fields in electron-only reconnection and regular reconnection in shock-driven turbulence
Presentation Type
Talk
Presenter Format
Virtual Meeting Talk
Topic
Fundamental Processes in Comparative Magnetospheres
Start Date
13-5-2022 3:15 PM
Abstract
In the Earth’s quasi-parallel bow shock, shock-driven turbulence generates current sheets, and MMS has been observing both electron-only reconnection, where only electron jets are generated, and regular reconnection, where both ion jets and electron jets are generated. To investigate the reconnection electric fields in shock-driven turbulence in the Earth’s bow shock, we performed 2D particle-in-cell simulations. In this presentation, we will discuss that the reconnection electric field in shock-driven reconnection is unusually larger than the prediction of the reconnection electric field in the standard laminar reconnection. In electron-only reconnection, the outflow speed reaches local electron Alfven speed. In some electron-only reconnection regions, only a one-sided electron jet is generated, and the region in the other side becomes an additional inflow region. We demonstrate that the outflow speed in such an unusual one-sided jet also reaches of the order of electron Alfven speed. In regular reconnection, the ion outflow speed also becomes 10 times the Alfven speed due to the ion reflection by the shock. As a result of the high speed jet, the convection electric field due to the outflows becomes a square root of the mass ratio times larger than that in the standard laminar reconnection, and the reconnection electric field reaches the same order. MMS observations of electron-only reconnection in the Earth’s magnetosheath show that electron outflow jets reach of the order of electron Alfven speed, and the reconnection electric field becomes much larger than the prediction in the standard laminar reconnection.
Strong reconnection electric fields in electron-only reconnection and regular reconnection in shock-driven turbulence
In the Earth’s quasi-parallel bow shock, shock-driven turbulence generates current sheets, and MMS has been observing both electron-only reconnection, where only electron jets are generated, and regular reconnection, where both ion jets and electron jets are generated. To investigate the reconnection electric fields in shock-driven turbulence in the Earth’s bow shock, we performed 2D particle-in-cell simulations. In this presentation, we will discuss that the reconnection electric field in shock-driven reconnection is unusually larger than the prediction of the reconnection electric field in the standard laminar reconnection. In electron-only reconnection, the outflow speed reaches local electron Alfven speed. In some electron-only reconnection regions, only a one-sided electron jet is generated, and the region in the other side becomes an additional inflow region. We demonstrate that the outflow speed in such an unusual one-sided jet also reaches of the order of electron Alfven speed. In regular reconnection, the ion outflow speed also becomes 10 times the Alfven speed due to the ion reflection by the shock. As a result of the high speed jet, the convection electric field due to the outflows becomes a square root of the mass ratio times larger than that in the standard laminar reconnection, and the reconnection electric field reaches the same order. MMS observations of electron-only reconnection in the Earth’s magnetosheath show that electron outflow jets reach of the order of electron Alfven speed, and the reconnection electric field becomes much larger than the prediction in the standard laminar reconnection.
