Determination of electron-plasma temperature by measuring the propagation velocity of plasma-diffusion waves with the mixture gases of Ar-N2 in the atmospheric pressure plasma jets

Summary form only given. From the measuring data of plasma jet propagation with ICCD camera, the determination method of the electron temperature is introduced. The bullet propagation has been analyzed by the plasma diffusion waves propagating with the group velocity of wave-packet as u_g ~ c_s²/u_n where c_s is the velocity of acoustic wave and u_n is the velocity of plasma diffusion. The plasma-jet device is made by the syringe-needle electrode combined with the glass tube as it was introduced in [Cho G.S. et al, (2013)]. A high-voltage AC-power is supplied to the electrode of syringe needle through the ballast capacitor with the inverter of DC to AC of 40 kHz of 3.0 kV. The mixture gases of Ar and N₂ are investigated with the flow late about 400 sccm. Ar-N₂ Plasma Jet is one of the important issues in the applications of bio-medicine. The gases with the mixture ratio are used as: Ar(100%), Ar(98%) + Ne(2%) and Ar(95%) + Ne(5%), respectively. According to the mixture-ratio with ICCD, the group velocity of plasma propagation is observed as: 267 km/s, 305 km/s, and 313 km/s, respectively. The velocity of ion-acoustic wave is calculated to be 1.16 km/s, 1.24 km/s, and 1.25 km/s, respectively. The electron temperature is obtained as: 0.55 eV, 0.63 eV, and 0.65 eV, respectively.