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arXiv · 1210.1253

Temperature, Abundance, and Mass Density Profiling of the Perseus Galaxy Cluster

Paul Geringer·Matthew Wampler-Doty·Melville Ulmer
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Abstract

Detailed temperature and abundance radial profile maps have revealed a significant lack of homogeneity within the Perseus Galaxy cluster. Previous surveys of Perseus with the Suzaku telescope, which has a worse angular resolution and less light collecting area than XMM-Newton, revealed over-densities of X-Ray emission. These results provide evidence that the baryon fraction exceeds the universal average, which we had initially hoped to study. We have yet to confirm or deny the existence of clumping in these regions, which could explain such over-abundance of X-Ray emission. This project offers a framework of efficient, automated processing techniques to "clean" images of noise from the mechanics of the telescope, background radiation from local sources such as the solar wind, and more distant sources such as background AGN. The galaxy cluster studied in this project contains high levels of contamination due to its line-of-sight position close to the dust- and star-filled arms of the Milky Way galaxy. Rigorous spectral model fitting of the cluster employ multiple parameters dedicated to accounting for these contaminations. The framework created from this analysis technique will provide the opportunity to expand this analysis to any nearby galaxy cluster, such as the Virgo, Coma, and Ophiuchus Clusters. This research should provide significant insight into how matter, both baryonic and dark matter, is distributed throughout diffuse cluster systems, as well as give clues to the origin of the ICM.

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Paul Geringer, Matthew Wampler-Doty, Melville Ulmer. 2012-10-03. Temperature, Abundance, and Mass Density Profiling of the Perseus Galaxy Cluster. https://arxiv.org/abs/1210.1253

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