Determining the Cosmic Distance Scale with Galaxy Clusters

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Determining the Cosmic Distance Scale with Galaxy
Clusters

• Erik Reese
• University of California, Berkeley

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The Sunyaev-Zeldovich Effect
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BIMA OVRO
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(No Transcript)
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Distance Calculation
With geometry of the cluster
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Hubble Constant
With z and geometry of the universe
Independent of the extra-galactic distance ladder!
For a sample of clusters, fit to the theoretical
DA relation, where H0 is the normalization
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Angular Diameter Distances Present
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H0 Current Results

• Ryle ? 5 clusters (Jones et al. 2003)
• OVRO 5m ? 7 clusters (Mason et al. 2000)
• OVRO/BIMA ? 18 clusters (Reese et al. 2002)

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H0 Current Results

• Combined ? 41 distances

Reminder All ROSAT data
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Systematics
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Chandra
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Angular Diameter Distances Chandra
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DA Future
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Supernovae Type Ia
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Challenges

• Systematics
• Modeling
• Sample selection
• Sample sizes
• Unbiassed selection criteria
• Wonky clusters
• Convince X-ray TACs
• High redshift?cosmology

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SZE Surveys

• Large samples of clusters
• High redshift clusters
• Clean selection function

Holder et al. 2000
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Simulations
Courtesy of Martin White
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Summary

• H0 independent of extragalactic distance ladder
• Systematics are approachable
• SZE Surveys
• Large numbers of clusters
• High redshift
• Sample selection
• Symbiotic with cluster number counts