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arXiv · 1203.5538

Optimizing Observational Strategy for Future Fgas Constraints

Silvia Galli·James G. Bartlett·Alessandro Melchiorri
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Abstract

The Planck cluster catalog is expected to contain of order a thousand galaxy clusters, both newly discovered and previously known, detected through the Sunyaev-Zeldovich effect over the redshift range 0 < z < 1. Follow-up X-ray observations of a dynamically relaxed sub-sample of newly discovered Planck clusters will improve constraints on the dark energy equation-of-state found through measurement of the cluster gas mass fraction fgas. In view of follow-up campaigns with XMM-Newton and Chandra, we determine the optimal redshift distribution of a cluster sample to most tightly constrain the dark energy equation of state. The distribution is non-trivial even for the standard w0-wa parameterization. We then determine how much the combination of expected data from the Planck satellite and fgas data will be able to constrain the dark energy equation-of-state. Our analysis employs a Markov Chain Monte Carlo method as well as a Fisher Matrix analysis. We find that these upcoming data will be able to improve the figure-of-merit by at least a factor two.

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Silvia Galli, James G. Bartlett, Alessandro Melchiorri. 2012-03-25. Optimizing Observational Strategy for Future Fgas Constraints. https://doi.org/10.1103/physrevd.86.043516

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