EVOLUTION AND STRATIFICATION OF A PLASMA CLOUD SURROUNDING A PELLET

The 2D equation system for an ionized ablatant density integrated along the magnetic field lines and for a polarization potential is solved numerically. The pellet is modelled by a plasma source of given intensity and spatial dimensions. The effects of a non-uniform tokamak magnetic field are taken into account. It has been shown that the vertical drift current inside the ionized ablatant produces the polarization that causes the ablatant drift in the direction of a tokamak major radius. The resulting E x B drifts lead to a rather complicated plasma cloud shape resembling a 'mushroom' with two clouds connected by a narrow 'stem'. The 'stem' is unstable and splits into separate striations.