Confining proton beams with longitudinal magnetic fields: Monte Carlo calculations

The problem of the lateral containment of a 160 MeV proton beam interacting with a medium simulating biological material was studied. The confining ac tion of a longitudinal magnetic held was calculated by means of Monte Carlo simulation, where scattering and motion in the magnetic field were treated simultaneously. Appreciable compression of the beam could only be achieved using fields of the order at least 50 T, much beyond the realm of practica l feasibility. (C) 2000 American Association of Physicists in Medicine. [S0 094-2405(00)01110-X].