MUM: Flexible precise Monte Carlo algorithm for muon propagation through thick layers of matter - art. no. 074015

We present a new Monte Carlo muon propagation algorithm mum (muons+medium) which possesses some advantages over analogous algorithms presently in use. The most important features of this algorithm are described. The results o n the test for the accuracy of the treatment of the muon energy loss with m um are presented and analyzed. It is evaluated to be of 2 x 10(-3) or bette r, depending upon simulation parameters. The contributions of different sim plifications, which are applied at Monte Carlo muon transportation to the r esulting error, are considered and ranked. It is shown that when simulating muon propagation through a medium it is quite enough to account only for f luctuations in radiative energy loss with the fraction of energy lost being as large as >0.05-0.1. Selected results obtained with mum are given and co mpared with ones from other algorithms.