Plasma-beam interaction experiments at TIT

The electron density decreases as a power function of the distance from the polyethylene surface. Along the laser axis, the electron density is independent of the distance between z=9 and z=30 mm. This region is a good candidate for uniform plasma although the density is as low as 3×10¹⁶ cm⁻³. The ions of Li- from a sputter ion source must be intensified to improve the counting statistics. The present plasma contains a considerable amount of carbon ions in low-charge states. These not-fully ionized carbon ions interact with the incident ion beam nearly as neutral atoms. The problem of low degree of ionization can be solved by forming laser plasma of lithium or solid hydrogen instead of the polyethylene.