Comparison of Galaxy Clusters Selected by Weak-lensing, Optical Spectroscopy, and X-Rays in the Deep Lens Survey F2 Field
Abstract
We compare galaxy clusters selected in Chandra and XMM-Newton X-ray observations of the 4 deg2 Deep Lens Survey (DLS) F2 field to the cluster samples previously selected in the same field from a sensitive weak-lensing shear map derived from the DLS and from a detailed galaxy redshift survey—the Smithsonian Hectospec Lensing Survey (SHELS). Our Chandra and XMM-Newton observations cover 1.6 deg2 of the DLS F2 field, including all 12 weak-lensing peaks above a signal-to-noise ratio of 3.5, along with 16 of the 20 SHELS clusters with published velocity dispersions >500 km s-1. We detect 26 extended X-ray sources in this area and confirm 23 of them as galaxy clusters using the optical imaging. Approximately 75% of clusters detected in either X-ray or spectroscopic surveys are found in both; these follow the previously established scaling relations between velocity dispersion, L X, and T X. A lower percentage, 60%, of clusters are in common between X-ray and DLS samples. With the exception of a high false-positive rate in the DLS weak-lensing search (5 out of 12 DLS candidates appear to be false), differences between the three cluster detection methods can be attributed primarily to observational uncertainties and intrinsic scatter between different observables and cluster mass.
- Publication:
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The Astrophysical Journal
- Pub Date:
- May 2014
- DOI:
- 10.1088/0004-637X/786/2/125
- Bibcode:
- 2014ApJ...786..125S
- Keywords:
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- galaxies: clusters: general;
- gravitational lensing: weak;
- X-rays: galaxies: clusters