Interaction of a finite-duration Alfvén wave with a trans-Alfvénic shock in space plasmas Original Research Article

The interaction of a finite-duration Alfvén wave with a trans-Alfvénic shock wave (TASW) is considered. The Alfvén wave consists of two pulses of opposite sign and equal duration, and it is supposed to leave the TASW unchanged after it passes through the shock transition layer. It is shown that, although this does eventually happen, the time required for the shock to recover is much larger than the time of its interaction with the Alfvén wave. This means that in reality the shock never comes to a steady state, because during the recovery process it will most likely be hit by another perturbation, which will not allow the shock to evolve to the initial state.