  In this study, we describe a procedure of topology optimization in the
framework of the linear Boltzmann equation, implemented using a reference
Monte-Carlo particle transport code. This procedure can design complex
structures that optimize the transport of particles, according to preset
objectives and constraints. Although simple and perfectible, this procedure was
successfully tested on a series of difficult problems, with results
outperforming human capabilities. Improved, it could be used to assist or
automate the design of particle optics or nuclear devices.
