Browsing by Subject "methods: data analysis"

Now showing 1 - 4 of 4
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    A simple model for global H i profiles of galaxies
    (2014) Stewart, I M; Blyth, S- L; de Blok, W J G
    Context. Current and future blind surveys for H i generate large catalogs of spectral lines for which automated characterisation would be convenient.
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    Open Access
    Accurate Recovery of H i Velocity Dispersion from Radio Interferometers
    (2017) Ianjamasimanana, R; Blok, W J G de; Heald, George H
    Gas velocity dispersion measures the amount of disordered motion of a rotating disk. Accurate estimates of this parameter are of the utmost importance because the parameter is directly linked to disk stability and star formation. A global measure of the gas velocity dispersion can be inferred from the width of the atomic hydrogen (H I) 21 cm line. We explore how several systematic effects involved in the production of H I cubes affect the estimate of H I velocity dispersion. We do so by comparing the H I velocity dispersion derived from different types of data cubes provided by The H I Nearby Galaxy Survey. We find that residual-scaled cubes best recover the H I velocity dispersion, independent of the weighting scheme used and for a large range of signal-to-noise ratio. For H I observations, where the dirty beam is substantially different from a Gaussian, the velocity dispersion values are overestimated unless the cubes are cleaned close to (e.g., ˜1.5 times) the noise level.
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    Open Access
    Generalized Fisher matrices
    (2014) Heavens, A F; Seikel, M; Nord, B D; Aich, M; Bouffanais, Y; Bassett, B A; Hobson, M P
    16.04.15 KB Ok to add accepted version to spiral
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    Open Access
    Towards automatic classification of all WISE sources
    (2016) Kurcz, A; Bilicki, M; Solarz, A; Krupa, M; Pollo, A; Małek, K
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