Focusing of Macroparticle Projectiles

The electrostatic acceleration of small particles to hyper-velocities is a way to get high temperatures by hypervelocity impact. In order to get fusion these particles should be bunched together in order to check the Lawson criterion. The longitudinal focusing of a beam of macroparticles is discussed in analogy with klystron theory. An ideal potential law and a sinusoidal potential law are considered. Because of the low charge/mass ratio of macroparticles, the frequencies involved are extremely low.