ANGULAR BIASING OF THE COLLISION PROCESS IN MULTIGROUP MONTE CARLO CALCULATIONS.

Description of an angular biasing technique that can be employed in multigroup Monte Carlo radiation transport calculations. This technique involves an alteration of the collision kernel of particle random walk. It can be easily implemented and can result in a substantial variance reduction. Implementation of this technique in the MORSE computer code is described. A deep-penetration test problem demonstrates the variance reduction. These results are applicable to shielding calculations.