The method implemented in **GNU Archimedes** is the Monte Carlo one. So every particle carries a statistical weight which is a piecewise-function of the position. The greater is the statistical weight, the greater is the number of super-particles in a cell. In this version of **GNU Archimedes**, the statistical weigth the user can specify is that of the cell in which the density is at maximum. In the other cells, the statistical weigth is opportunely calculated. If the user, for example, wants to set the statistical weight equal to 1500, he/she have to write in the input file

STATISTICALWEIGHT 1500Pay attention to the fact that the bigger is the statistical weight the longer will be simulation run-time.

Didier Link 2007-05-18