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arXiv · 1009.2736

Are Galaxy Clusters Suggesting an Accelerating Universe?

J. A. S. Lima·R. F. L. Holanda·J. V. Cunha
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Abstract

The present cosmic accelerating stage is discussed through a new kinematic method based on the Sunyaev- Zel'dovich effect (SZE) and X-ray surface brightness data from galaxy clusters. By using the SZE/X-ray data from 38 galaxy clusters in the redshift range $0.14 \leq z \leq 0.89 $ [Bonamente et al., Astrop. J. {\bf 647}, 25 (2006)] it is found that the present Universe is accelerating and that the transition from an earlier decelerating to a late time accelerating regime is relatively recent. The ability of the ongoing Planck satellite mission to obtain tighter constraints on the expansion history through SZE/X-ray angular diameters is also discussed. Our results are fully independent on the validity of any metric gravity theory, the possible matter- energy contents filling the Universe, as well as on the SNe Ia Hubble diagram from which the presenting accelerating stage was inferred.

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J. A. S. Lima, R. F. L. Holanda, J. V. Cunha. 2010-09-14. Are Galaxy Clusters Suggesting an Accelerating Universe?. https://doi.org/10.1063/1.3462638

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