It is widely believed that magnetic reconnection plays an important role in various eruptive phenomena of space and astrophysical plasmas. The mechanism of anomalous resistivity, however, has been an open and unsolved problem. The chaos-induced resistivity proposed by Yoshida et al. is one of possible mechanisms for anomalous resistivity. By use of the test particle simulation, the present work studies the chaos-induced resistivity for different configurations of reconnection magnetic fields and its distribution in different chaos regions of reconnection current sheets. The results show that the chaos-induced resistivity can be 6 – 7 orders of magnitude higher than the classical Spitzer resistivity in the X-type chaos regions and 5 orders of magnitude in the O-type chaos regions. Moreover, in the X-type chaos regions the chaos-induced resistivity of the magnetized case is higher by a factor of 2 to 3 times than that of the unmagnetized case, but in the O-type chaos regions the chaos-induced resistivity of the magnetized case is close to or lower than that of the unmagnetized case. The present work is helpful to the understanding of the dynamics of reconnection current sheets, especially of the generation mechanism of the anomalous resistivity of collisionless reconnection regions.

人们普遍认为，磁重联在空间和天体物理等离子体的各种喷发现象中起着重要作用。然而，异常电阻率的机制一直是一个悬而未决的问题。Yoshida 等人提出的混沌诱导电阻率。是异常电阻率的可能机制之一。本工作利用测试粒子模拟，研究了不同重联磁场配置下的混沌电阻率及其在重联电流片不同混沌区域的分布。结果表明，混沌引起的电阻率在 X 型混沌区比经典斯皮策电阻率高 6-7 个数量级，在 O 型混沌区比经典斯皮策电阻率高 5 个数量级。而且，在 X 型混沌区，磁化外壳的混沌电阻率比未磁化外壳高 2 到 3 倍，但在 O 型混沌区，磁化外壳的混沌电阻率高接近或低于未磁化的情况。目前的工作有助于理解重联电流片的动力学，特别是无碰撞重联区异常电阻率的产生机制。