  Kinetic aspects of the ion current layer at the center of a reconnection
outflow exhaust near the X-type region are investigated by a two-dimensional
particle-in-cell (PIC) simulation. The layer consists of magnetized electrons
and unmagnetized ions that carry a perpendicular electric current. The ion
fluid appears to be nonideal, sub-Alfvenic, and nondissipative. The ion
velocity distribution functions contain multiple populations such as global
Speiser ions, local Speiser ions, and trapped ions. The particle motion of the
local Speiser ions in an appropriately rotated coordinate system explains the
ion fluid properties very well. The trapped ions are the first demonstration of
the regular orbits in the chaotic particle dynamics [Chen and Palmadesso, J.
Geophys. Res., 91, 1499 (1986)] in self-consistent PIC simulations. They would
be observational signatures in the ion current layer near reconnection sites.
