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تسجيل مستخدم جديدXMM-Newton Observations of Extra-planar Gas in Nearby Starburst Galaxies
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We report on first results of XMM-Newton observations of nearby starburst galaxies that form part of a multi-wavelength study of gaseous halos around late-type spiral galaxies and their dependence on the level of star formation activity in the underlying disks. XMM-Newton, with its extraordinary sensitivity for faint extended X-ray emission, is used to derive spatial and spectral properties of the very hot extraplanar/halo gas. For example, spectral models can be tested and hot gas properties like density, mass and energy can be estimated. Comparing the distribution of the halo X-ray emission with optical filaments and/or observed magnetic field structures uncovers interesting correlations on which work just has started. Our study aims - in general - at assessing the importance of galactic halos as repositories of a metal-enriched hot medium and their significance in terms of galactic chemical evolution and possible metal enrichment of the intergalactic medium.
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