A Direct Measurement of the Linear Bias of Mid-infrared-selected Quasars at z ≈ 1 Using Cosmic Microwave Background Lensing
We measure the cross-power spectrum of the projected mass density as traced by the convergence of the cosmic microwave background lensing field from the South Pole Telescope (SPT) and a sample of Type 1 and 2 (unobscured and obscured) quasars at 〈z〉 ~ 1 selected with the Wide-field Infrared Survey E...
Published in: | The Astrophysical Journal |
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Main Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
American Astronomical Society
2013
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Subjects: | |
Online Access: | https://authors.library.caltech.edu/42227/ https://authors.library.caltech.edu/42227/1/2041-8205_776_2_L41.pdf https://authors.library.caltech.edu/42227/7/1307.1706v2.pdf https://resolver.caltech.edu/CaltechAUTHORS:20131104-135724437 |
Summary: | We measure the cross-power spectrum of the projected mass density as traced by the convergence of the cosmic microwave background lensing field from the South Pole Telescope (SPT) and a sample of Type 1 and 2 (unobscured and obscured) quasars at 〈z〉 ~ 1 selected with the Wide-field Infrared Survey Explorer, over 2500 deg^2. The cross-power spectrum is detected at ≈7σ, and we measure a linear bias b = 1.61 ± 0.22, consistent with clustering analyses. Using an independent lensing map, derived from Planck observations, to measure the cross-spectrum, we find excellent agreement with the SPT analysis. The bias of the combined sample of Type 1 and 2 quasars determined in this work is similar to that previously determined for Type 1 quasars alone; we conclude that obscured and unobscured quasars trace the matter field in a similar way. This result has implications for our understanding of quasar unification and evolution schemes. |
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