Modeling of Stark-Broadened Lines in a Fluctuating Edge Plasma

A line shape model that accounts for low-frequency fluctuations is applied to the Balmer series of the hydrogen isotopes (atomic transitions n -> 2). The plasma fluid parameters (density, temperature, etc.) are described as random variables characterized by a prescribed joint probability density function. A special emphasis is devoted to Stark broadened lines, which are sensitive to the plasma density. It is shown that fluctuations can lead to a significant increase of the line width if the fluctuation level Delta N-e/< N-e > (with < N-e > and Delta N-e being respectively the density averaged along the line-of-sight and its RMS value) is large. (C) 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim