INSTABILITY OF AN ALTERNATING-CURRENT POSITIVE COLUMN

Journal Article · Fri May 01 04:00:00 EDT 1964 · Physics of Fluids (U.S.)

DOI:https://doi.org/10.1063/1.1711277· OSTI ID:4006470

Rugge, H F; Pyle, R V

The positive column of a glow discharge in a magnetic field is known to become macroscopically unstable at some critical magnetic field. The driving mechanism proposed by Kadomtsev and Nedospasov for the growth of a helical (m = 1) perturbation is such that the periodic reversal of the axial electric field at a frequency greater than a critical frequency would be expected to lead to stability. This critical frequency is expected to be approximately the e-folding rate. An experimental study was made in d-c and half-wave rectified-current discharges and in square and sinusoidal a-c glow discharges in H/sub 2/, D/sub 2/ , He, Ne, and Ar at frequencies as high as 70 kcps. Over a wide range of frequencies the half-wave rectified discharges yielded instabilities whose onset and helical nature duplicated those of the d-c cases. However, the instability in the a-c discharges was indeed suppressed as the frequency of electric field reversal was increased. The frequency-dependent suppression of the instability is compared with theoretical growth rates. The effect of including several m modes is calculated and good qualitative agreement is obtained with the Kadomtsev and Nedospasov model. However, better quantitative agreement is obtained when the Johnson and Jerde modification is employed. (auth)

• Research Organization: Univ. of California, Berkeley
• NSA Number: NSA-18-021412
• OSTI ID: 4006470
• Report Number(s): UCRL-10698(Rev.); 0031-9171
• Journal Information: Physics of Fluids (U.S.), Journal Name: Physics of Fluids (U.S.) Vol. Vol: 7; ISSN PFLDA
• Country of Publication: United States
• Language: English

Related Subjects

ALTERNATING CURRENT
ARGON
CURRENTS
DEUTERIUM
DIRECT CURRENT
ELECTRIC DISCHARGES
ELECTRIC FIELDS
FREQUENCY
GLOW DISCHARGES
HELICAL INSTABILITY
HELIUM
HYDROGEN
KINK INSTABILITY
MAGNETIC FIELDS
MEASURED VALUES
NEON
OSCILLATIONS
PHYSICS
PINCH
PLASMA
POSITIVE COLUMN
STABILITY