Publication Details (including relevant citation information):
Vacuum 43(3), 189 - 193 (1992).
Micro-particles in the beam chamber of a TRISTAN vacuum system were investigated from the point of view of suppressing micro-particles trapped in the accumulation ring. Micro-particles coming from ion pumps (IP) and distributed ion pumps (DIP), aluminum alloy particles produced during treatment of aluminum alloy chambers for welding, micro-particles from the environment, i.e. soil (granite rocks or amphiboles), particles of concrete and painting materials were identified. A molten iron particle found in a chamber suggests interaction between the particle and bunched electron beam. Most of the particles coming from outside the chambers can be avoided by using high class clean rooms. The particles from the ion pumps can be reduced using different pumps which do not emit particles. The particles produced during assembly of, for example, DIP must be suppressed by accepting different assembling methods from the traditional ones.