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The Northern ROSAT All-Sky (NORAS) Galaxy Cluster Survey I: X-ray Properties of Clusters Detected as Extended X-ray Sources

H. Boehringer·W. Voges·J. P. Huchra·B. McLean·R. Giacconi·P. Rosati·R. Burg·J. Mader·P. Schuecker·D. Simic·S. Komossa·T. H. Reiprich·J. Retzlaff·J. Truemper
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Abstract

In the construction of an X-ray selected sample of galaxy clusters for cosmological studies, we have assembled a sample of 495 X-ray sources found to show extended X-ray emission in the first processing of the ROSAT All-Sky Survey. The sample covers the celestial region with declination $δ\ge 0°$ and galactic latitude $|b_{II}| \ge 20°$ and comprises sources with a count rate $\ge 0.06$ counts s$^{-1}$ and a source extent likelihood of 7. In an optical follow-up identification program we find 378 (76%) of these sources to be clusters of galaxies. ...

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H. Boehringer, W. Voges, J. P. Huchra, B. McLean, R. Giacconi, P. Rosati, R. Burg, J. Mader, P. Schuecker, D. Simic, S. Komossa, T. H. Reiprich, J. Retzlaff, J. Truemper. 2000-03-22. The Northern ROSAT All-Sky (NORAS) Galaxy Cluster Survey I: X-ray Properties of Clusters Detected as Extended X-ray Sources. https://doi.org/10.1086/313427

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