C. F. F. Karney, D. P. Stotler, and
A. Yu. Pigarov
Princeton Plasma Physics Laboratory
Princeton, NJ 08543-0451
Sherwood meeting, Philadelphia, PA, Mar. 18-20, 1996, Paper1C02
Degas 2 is a Monte Carlo code to compute neutral gas
transport with a primary application to the understanding of tokamak
divertors. In this paper, we describe the procedure for computing Monte
Carlo scores which are a statistical measure of quantities that the code
attempts to measure. There are two issues to consider: (a) How to compute
these scores with minimum variance. Degas 2 addresses this by using a
track length estimator which it is able to do efficiently because of the
way the geometry is handled. (b) How to let the user specify which scores
need to be computed. Degas 2 lets the user specify quantities that are
scored either when a test flight traverses a volume or intersects a
surface. This lets users specify the usual quantities of interest for
coupling to a plasma code (e.g., momentum transfer) and for simulating a
diagnostic (e.g., an 
detector).