Effects of the Length-width Ratio of Current Sheet on Asymmetry Multiple X-line Reconnection

Effects of the length-width ratio of current sheet (${L_x}$) on asymmetry multiple X-line reconnection are investigated using a two-dimensional compressible resistive Magnetohydrodynamics (MHD) model. It is found that multiple-X lines induced by secondary tearing instability occur during the asymmetry reconnection processes when ${L_x}$ exceeds a critical value. Multiple X-line reconnection occurs faster as ${L_x}$ becomes larger, and percent of secondary island is also increases. For large ${L_x}$ cases, locations of the reconnection points of asymmetry multiple X-line reconnection and sizes of the secondary island are tend to stationary with the evolution of the multiple X-line reconnection, which is consistent to the Magnetospheric Multiscale (MMS) observations. The results here can be useful for understanding some observed data, even for the secondary tearing instability and multipleX-line reconnection observations.