Design and fabrication of a linear Paul trap for the study of space-charge-dominated beams

The collective motion of a single-species plasma in a radio-frequency quadrupole trap is physically almost equivalent to that of a charged-particle beam propagating through a periodic magnetic lattice. This fact suggests that one can experimentally study the behavior of space-charge-dominated beams by using a compact table-top device. At Hiroshima University, a Paul trap system dedicated to beam-physics purposes has been designed and is now under construction. Controllable, pulsed radio-frequency voltages, instead of ordinary sinusoidal voltages, are applied to the trap electrodes such that collective beam dynamics in various lattice structures can be explored. The system is equipped with a laser cooler that enables us to adjust the tune depression of a Ca+ plasma. In this paper, the basic design concept of the trap and the detailed system configuration are presented.