Benchmarking of Collision Operators with Momentum Source Corrections

H. Maaßberg , and C.D. Beidler Max-Planck-Institut für Plasmaphysik, EURATOM Association, D-17491 Greifswald, Germany (Dated: March 22, 2010) Abstract Several linearised collision operator models with parallel momentum conservation enforced by source functions are benchmarked against the correct collision operator based on Rosenbluth potentials. The model operators without energy diffusion allow for an analytic solution of a generalised Spitzer problem. For the other operators under investigation, an integro-differential equation is solved. The benchmarking is performed both for the parallel conductivity with the ions assumed at rest and for the bootstrap current, where ion and electron flows are collisionally coupled. Accuracy of the results obtained with the operators varies from rather poor in the case of the simplest mono-energetic model to quite satisfactory for the models employing an energy-weighted parallel momentum source function.