Numerical Study on the Gas Temperature of Microwave Discharge Rare Gas Plasmas as a Rarified Gas Dynamic System

We report numerical simulation of gas temperature of microwave discharge plasma of rare gases by weighted-DSMC method. Our numerical simulation showed that neutral particles are heated by collisions with ions. It is found that the average temperature becomes higher for heavier rare gas discharge plasmas, which agrees with our previous experiments. It is also found that ions are accelerated by ambipolar electric field in the discharge tube. The axial dependence of the gas temperature becomes more remarkable for the heavier rare gas plasmas. The temperature gradient results in neutral depletion at the central region of the cylindrical plasma, which is also more remarkable for the heavier rare gas plasmas. It further causes the discrepancy of radial ion distribution from the Bessel distribution.