München 2019 – wissenschaftliches Programm
P 18.41: Poster
Donnerstag, 21. März 2019, 16:30–18:30, Foyer Audimax
Windowless VUV spectroscopy of an RF-driven atmospheric pressure helium plasma jet with admixtures of oxygen or nitrogen — •Fenja Severing, Judith Golda, and Jan Benedikt — Institute of Experimental and Applied Physics, Kiel University, Germany
Cold atmospheric pressure plasmas have a wide field of applications. Their low temperature, high density of reactive particles and emission of energetic photons can be used e.g. for activation of surfaces, disinfection of gas and water or for medical treatment. VUV radiation plays an important role in these applications but the generation mechanisms are still unknown. In this work, further insights into the mechanisms occurring in an atmospheric pressure plasma are gained by optical emission spectroscopy. To provide accurate spectral observations in the VUV region, the experimental setup must be free of VUV radiation absorbing material. This is realized by a continuous helium flow into the VUV spectrometer as well as a windowless beam path.
Here, we present optical emission measurements of high energetic photons between 50 nm and 200 nm in an atmospheric pressure plasma jet with molecular oxygen and nitrogen admixtures. The intensity characteristics of the observed spectral lines are discussed for different admixture concentrations. Interpretation based on the Corona-Model indicates changes of the electron energy distribution function (EEDF).