ON THE IDEAL INITIAL-VALUE PROBLEM FOR THE NEUTRAL SHEET

The ideal initial value problem for the neutral sheet is considered, w ith the emphasis on fieldwise-independent, infinitesimal velocity dist urbances. It is shown analytically that cross-field velocity perturbat ions persist, and that they also set up fieldwise magnetic disturbance s that grow algebraically in time. When these disturbances attain fini te amplitude they should distort the neutral sheet configuration, and hence they could provide an alternative route by which magnetic reconn ection can become turbulent. Some supporting numerical simulations, pe rformed at large Lundquist numbers, are then described. In an Appendix the analysis is extended to include fieldwise-dependent disturbances.