  The laboratory simulations of jets from young stars that have been carried
out for many years at plasma focus facilities allow the internal structure of
the active regions emerging during the interaction of the jet with the
surrounding plasma to be studied in detail. We have found a new wide class of
solutions for the equations of ideal magnetohydrodynamics describing the closed
axisymmetric stationary flows that are apparently realized in the active
regions. Such flows are shown to well reproduce the internal structure of the
plasma structures observed in laboratory simulations of astrophysical jets.
