Speaker
Description
We have investigated how to produce multicharged
ions efficiently. Recently, we have focused on waves
propagations in plasma and conducted the Upperhybrid
Resonance (UHR) experiments. [1] We have
also conducted experiments heating by the coaxial
semi-dipole antenna to enhance the right-hand
polarization wave, which contributes to ECR. [2]
Multicharged ion beams have been improved using
various means, e.g., the increase of the magnetic
field and the microwave frequency, the DC biased
plate-tuner, mixing low z gases, and the multiplex
frequencies heating. However, the microwave
launching position has been empirically determined
on conventional ECRIS's. There is still some room for
improvement with the respect to more efficient
excitation of the wave propagation. In this research,
we estimate the wave propagation near the ECR
zone, and in the opposite peripheral region beyond it.
We measure plasma parameters in those regions by
two Langmuir probes inserted into each location at
the same time. In near future, we optimize the
microwave-launching in the case of the fundamental
frequency for ECR and the second frequency for UHR
in order to enhance their incidence to the vacuum
chamber.