Self-regulation of the reconnecting current sheet in relativistic pair plasmas

A thin current layer plays an important role in magnetic reconnection, because the microphysics in the region controls the magnetic dissipation rate. We investigate the detail structure of a reconnecting current sheet (RCS) in relativistic pair plasmas. Such RCS sometimes changes its current intensity through the reconnection electric field, so that it meets the outer physical conditions. However, in the relativistic regime, as soon as the current-carrying velocity reaches to its upper limit, typically an order of the light speed c, the mechanism breaks down and then the RCS finds the other way to compensate the required current. The evolution of the RCS and its self-regulating mechanism will be presented.