抄録
In argon and nitrogen plasma jet flows, the electron density measurements were made with microwave interferometer.
The obtained electron number density in the center of the flow was in the range from 1012 to 1013 1/cm3 for argon and from 1011 to 1012 1/cm3 for nitrogen. The former agreed with the results of the LANGMUIR probe measurements.
The phase shift, Δφ, of the microwave through the plasma due to the existence of a transient plasma is usually obtained from the output variation of the microwave interferometer, which is called a fringe. In this experiment it was obtained from the direct measurements of the microwave power passed through the each arm of the interferometer as well as the interferometer output. Some discussions were given in order to determine the sign and the integer part of it.
The interception-plate was also used to cut off the flow during the run.
