Title: Backward Monte-Carlo applied to muon transport,
Abstract: We discuss a backward Monte-Carlo technique for muon transport problem, with
emphasis on its application in muography. Backward Monte-Carlo allows exclusive
sampling of a final state by reversing the simulation flow. In practice it can
be made analogous to an adjoint Monte-Carlo, though it is more versatile for
muon transport. A backward Monte-Carlo was implemented as a dedicated muon
transport library: PUMAS. It is shown for case studies relevant for muography
imaging that the implementations of forward and backward Monte-Carlo schemes
agree to better than 1%.