Demonstration of an intense lithium beam for forward-directed pulsed neutron generation.

As an alternative to research nuclear reactors, a compact accelerator-driven neutron generator that uses a lithium beam driver could be a promising candidate since it produces almost no undesired radiation. However, providing an intense lithium-ion beam has been difficult, and it has been thought that the practical application of such a device would be impossible. The most critical problem of insufficient ion fluxes has been solved by applying a direct plasma injection scheme.

Plasma instability inside solenoid with laser ion source.

Using a solenoid with a laser ion source can suppress divergence of the expanding plasma; however, it has been found that the plasma becomes unstable in a certain magnetic field region. In the previous research, instability of the plasma after the solenoid was found. In this study, we investigated how the plasma instability changes inside the solenoid.

Feasibility study of a compact heavy ion source for investigation of laboratory magnetospheric plasma.

We are developing a laser ion source to provide a high brightness multi-charged heavy ion beam as a part of the heavy ion beam probe system, which will be used to diagnose plasma potential in the Ring Trap 1 device at the University of Tokyo. As a probe beam, Nb was selected, and a detailed laser irradiation condition was explored. It was found that the laser power density of 1.

Optimization of laser-target parameters for the production of stable lithium beam.

A laser ion source coupled with a radio frequency quadrupole linac accelerator is being proposed as a suitable system for the production of a low energy, high-current stable lithium beam. In order to maximize the lithium yield, plasmas generated by laser ablation of different materials based on lithium (Li, LiOH, and LiNbO) have been characterized by using a Faraday cup and an electrostatic ion analyzer in the time of flight configuration. A wide range of laser power density has been investigated (10-10 W/cm) using two Nd:YAG lasers operating at different wavelengths (1064 nm and 532 nm), pulse durations (6 ns and 17 ns), and maximum energies (1400 mJ and 210 mJ).