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XMM-Newton discovery of O VII emission from warm gas in clusters of galaxies

J. S. Kaastra·R. Lieu·T. Tamura·F. B. S. Paerels·J. W. A. den Herder
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Abstract

XMM-Newton recently discovered O VII line emission from ~2 million K gas near the outer parts of several clusters of galaxies. This emission is attributed to the Warm-Hot Intergalactic Medium. The original sample of clusters studied for this purpose has been extended and two more clusters with a soft X-ray excess have been found. We discuss the physical properties of the warm gas, in particular the density, spatial extent, abundances and temperature.

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J. S. Kaastra, R. Lieu, T. Tamura, F. B. S. Paerels, J. W. A. den Herder. 2003-05-22. XMM-Newton discovery of O VII emission from warm gas in clusters of galaxies. https://doi.org/10.1007/978-1-4020-2564-8_5

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