TURBULENT TRANSITION IN SOLAR SURGES

It has been suggested that a surge can be modelled as a jet travelling in a sheared magnetic field, and that the transition to turbulence of this ''MHD tearing jet'' can explain several key observed features. In this paper we present our preliminary results of the transition to turbulence via secondary instabilities of the MHD tearing jet. Our results confirm that turbulent transition can decelerate the surge, with decay times which compare well with surge data. Furthermore, we find that the turbulent MHD tearing jet forms magnetic field-aligned velocity filaments similar to those often observed in the surge flow field.