Measurement of the Ti X ion density in a theta pinch plasma utilizing a laser interferometer (abstract)

The increase in the radial line integral of the electron density in the NBS theta pinch plasma due to the ionization of titanium impurity has been measured with the use of a He–Ne laser heterodyne quadrature interferometer. Titanium is injected as an impurity into the base gas of hydrogen with the use of a coaxial gun discharge with titanium electrodes. The abundance of the Ti X ion density in the plasma is deduced in each discharge from the measured increase in electron density by knowing the temporal charge state distribution of Ti ions obtained by spectroscopic methods.