title: Feasibility of line-ratio spectroscopy on helium and neon as edge diagnostic tool for Wendelstein 7-X.
abstract: A beam emission spectroscopy system on thermal helium (He) and neon (Ne) has been set up at Wendelstein 7-X to measure edge electron temperature and density profiles utilizing the line-ratio technique or its extension by the analysis of absolutely calibrated line emissions. The setup for a first systematic test of these techniques of quantitative atomic spectroscopy in the limiter startup phase (OP1.1) is reported together with first measured profiles. This setup and the first results are an important test for developing the technique for the upcoming high density, low temperature island divertor regime.
authors.affiliation: Department of Engineering Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
authors.forename: T
authors.initials: T
authors.lastname: Barbui
authors.affiliation: Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Krychowiak
authors.affiliation: Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany.
authors.forename: R
authors.initials: R
authors.lastname: König
authors.affiliation: Department of Engineering Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
authors.forename: O
authors.initials: O
authors.lastname: Schmitz
authors.affiliation: Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA.
authors.forename: J M
authors.initials: JM
authors.lastname: Muñoz Burgos
authors.affiliation: Laboratory for Plasma Physics, Ecole Royale Militaire - Koninklijke Militaire School, 1000 Brussels, Belgium.
authors.forename: B
authors.initials: B
authors.lastname: Schweer
authors.affiliation: Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung-Plasmaphysik, Partner of the Trilateral Euregio Cluster (TEC), 52425 Jülich, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Terra
authors.affiliation: Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany.