THE AXISYMMETRICAL FOKKER-PLANCK-LANDAU O PERATOR

We establish a simplified form of the axisymmetric Fokker-Planck-Landa u operator (in the velocity space). In doing so, we derive a weak form ulation of this operator on which we get directly the conservation pro perties and the decay of the entropy as it is the case for the full th ree-dimensional operator (see [1]). A symmetrized version of this form ulation leads to a class of numerical schemes which satisfy these phys ical properties at the discrete level.