ESQ focusing for an intense, high-brightness H− beam: Emittance growth and its remedy

A simple, novel electrostatic quadrupole (ESQ) lens system has been developed to transport and focus an intense, high-brightness (normalized beam brightness ∼ 10
¹¹
A/m
²
rad
²
) H
⁻
beam. The physics of emittance growth in the ESQ transport system is studied in detail by computer simulation of beam dynamics, when the influence of various factors, e.g., input beam parameters, aberrations, misalignments, etc. has been examined. Possible methods to control the emittance growth have been suggested.