Takaya Masutani

STRIATED COLUMN APPEARING IN HIGH-FREQUENCY GAS DISCHARGE

Stationary striations appearing in the plasma column of low pressure argon h. f. discharge brought about in cylindrical discharge tube of diameter from 5.8 to 18 mm are investigated experimentally for the pressure range from 0.07 to 8 mmHg. Their spatial intervals (so-called “wave-length”) are proportional to the electrodes distance within a limited range of the wave-length. The relation between the wave-length and the electrodes distance is shown by sawteeth-like characteristics. The wave-length increases linearly as the radius of the discharge tube increases. But it decreases exponentially as the gas pressure increases. The influence of the frequency of the h. f. source does not exist over a range from 5 mc to 53 mc. The wave-length, however, increases as the h. f, power increases. When a d. c. voltage is superposed on the h. f. field through another pair of electrodes, striations move from positive side to negative side at a velocity proportional to the d. c. current. These results indicate that the st...