STUDING OF SOME PROPERTIES OF A ROTATING PLASMA

Abstract

A Homopolar device was designed to enable a rotating plasma to be investigated in a low current DC discharge The device includes three open windows right angle to the anode surface one of them for measurements purpose , and two others to connect the device to the vacuum system and to argon•gascylinder. Langmuir single and double probes were used to determine the discharge parameters at gas pressure in the range between (0.1 to 1.0) mbar , in the absence of a magnetic field . The electron temperature was measured in the absence of a magnetic field The measurements in the range of (7. 2 to 3. 9)

4 xl0

°K using the single probe and ( 7. 2 to 3. 9) X

the double probe at pressure range betv1een (0. 1 to 1. 0) mbar The electron temperature decreased by incteasing the gas pressure. The ions density was measured in the absence of a magnetic field by the single and the double probes The ions density increased by increasing gas pressure The measurements by the double probe showed that the range of ions density was (0.1 to 2 .15) X ionsjm3 by used Linear Extrapolation (LIN) method

and (0.04 to 1.89) by used Double Logarithmic Extrapolation (OLE)

method while the single probe showed that the ion density was

( 0. 09 to 1. 5) x 10

ionjm3

at pressure range between (0. 1 to

1.0) mbar