Atmospheric pressure plasma jets are a versatile, comparably cheap tool with a large potential for application in material coating or medicine, as they allow a localized treatment without expensive or inapplicable vacuum systems. Although the physics of atmospheric pressure plasma jets is partly understood, the in fluence of certain species such as ozone are still hardly investigated. To learn more about the plasma chemistry and underlying processes in these jets, it is necessary to investigate ozone concentrations by absorption spectroscopy. This contribution identifies important production and destruction mechanisms in a typical atmospheric pressure plasma jet setup. We observed that ozone density depends on parameters like power, admixture of oxygen and flow rate. Time resolved measurements revealed that the time scale for forming of ozone is in the order of tens of microseconds. Ozone is inhomogeneously formed over the length of the jet. In conclusion, ozone concentration largely varies with plasma parameters and can be controlled. This behavior will need to be considered in chemical modeling as well in the design of application oriented jets, especially for medical purposes.
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