Measurements of ion temperature and ion collective motion in an energetic arc

On an energetic arc, shapes of emitted spectral lines were investigated spectrographically, Ion temperatures from their halfwidths, velocities of collective rotational drift of emitting ions from their spectral inclinations on transverse observation, and velocities of collective axial motion from their wavelength shifts on longitudinal observation were respectively estimated. Maximum values obtained were: (1) 20 eV of ion temperature at the center between electrodes of the arc, (2) 7 x 10⁵ cm/sec of C⁺⁺ rotational drift velocity , (3) 1.5 x 10⁶ cm/sec of C⁺⁺ axial drift velocity. They increase with the decrease of neutral gas pressure. Increase of the arc current decreases the axial drift velocity, and increases the ion temperature. Increase of the axial magnetic field increases both the ion's rotational drift velocity and on a smaller degree the ion temperature. (author)