EAGER: Addressing Key Unsolved Issues in Reconnection Physics Through Linear Theory of Tearing Instability

本项目将研究是否可能成功地发展一种新的方法来推导空间等离子体撕裂模不稳定性的线性理论。这样一个线性理论将成为无碰撞等离子体中磁重联的完整非线性理论的基础。以前的线性撕裂模式的分析工作依赖于使用渐近方法，使方程易于处理。然而，完全动力学的粒子模拟表明，渐近方法在大多数现实的几何形状中崩溃了。本文的探索性研究有三个目的：（1）确定渐近方法失效的原因，并发展一种新的方法，用精确的线性Vlasov解来确定从线性理论直接过渡到非线性湍流的条件;（2）确定二次撕裂岛的形成是否是由于线性不稳定性; 3）研究有争议的问题，即线性模式特性是否对大型系统中的重联率有重大影响。这是一个有可能改变等离子体理论和模拟中磁重联处理方式的项目。 它可能会影响我们对太阳、太阳风、行星磁层和天体物理等离子体现象的理解。

This project will investigate the possibility that a new approach to deriving a linear theory of the tearing mode instability in space plasmas can be successfully developed. Such a linear theory would then form the basis of a full non-linear theory of magnetic reconnection in a collisonless plasma. Previous analytical work on the linear tearing mode relied on using an asymptotic approach to make the equations tractable. However, fullly kinetic, particle simulations have indicated that the asymptotic approach breakes down in most realistic geometries. The purpose of this exploratory resarch is threefold: 1) Determine why the asymptotic appoach breaks down and develop a new approach using an exact linear Vlasov solver to determine the conditions where a direct transition from linear theory to non-linear turbulence occurs; 2) Determine whether or not the formation of secondary tearing island formation is due to a linear instability; 3) Examine the controversial question of whether linear mode properties have a significant influence on the resulting reconnection rate in large systems. This is a project that has the potential to transform the way magnetic reconnection is treated in plasma theory and simulations. It could affect our understanding of phenomena on the sun, in the solar wind, in planetary magnetospheres and in astrophysical plasmas.