  A rotating pulsar creates a surrounding pulsar wind nebula (PWN) by steadily
releasing an energetic wind into the interior of the expanding shockwave of
supernova remnant or interstellar medium. At the termination shock of a PWN,
the Poynting-flux-dominated relativistic striped wind is compressed. Magnetic
reconnection is driven by the compression and converts magnetic energy into
particle kinetic energy and accelerating particles to high energies. We
carrying out particle-in-cell (PIC) simulations to study the shock structure as
well as the energy conversion and particle acceleration mechanism. By analyzing
particle trajectories, we find that many particles are accelerated by
Fermi-type mechanism. The maximum energy for electrons and positrons can reach
hundreds of TeV.
