[15p-2V-1~22] 8.1 Plasma production and control

△ [15p-2V-18] Atmospheric-pressure pulsed plasma diagnostics by laser measurements at room and cryogenic temperatures

〇Noritaka Sakakibara¹, Hitoshi Muneoka^1,2, Keiichiro Urabe^1,2,3, Ryoma Yasui¹, Kazuo Terashima¹ (1.Univ. of Tokyo., 2.JSPS Research Fellow, 3.Air Liquide Lab.)

Keywords:Atmospheric-pressure plasma,laser measurement,helium metastables

Atmospheric-pressure helium pulsed plasmas generated near or below room temperature were characterized by laser diagnostics. With focusing on the dependences on plasma gas temperature, the density and lifetime of helium metastables were estimated by laser absorption spectroscopy measurements and the plasma gas temperature was evaluated by near-infrared laser heterodyne interferometry. The gas temperature dependences of reactions relevant to helium metastables which causes a high density and a long lifetime of helium metastables at cryogenic temperatures, are also discussed.