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COSMOS: Three-dimensional Weak Lensing and the Growth of Structure

Massey, Richard and Rhodes, Jason and Leauthaud, Alexie and Capak, Peter and Ellis, Richard and Koekemoer, Anton and Refregier, Alexandre and Scoville, Nick and Taylor, James E. and Albert, Justin and Bergé, Joel and Heymans, Catherine and Johnston, David and Kneib, Jean-Paul and Mellier, Yannick and Mobasher, Bahram and Semboloni, Elisabetta and Shopbell, Patrick and Tasca, Lidia and Van Waerbeke, Ludovic (2007) COSMOS: Three-dimensional Weak Lensing and the Growth of Structure. Astrophysical Journal Supplement Series, 172 (1). pp. 239-253. ISSN 0067-0049.

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We present a three-dimensional cosmic shear analysis of the Hubble Space Telescope COSMOS survey, the largest ever optical imaging program performed in space. We have measured the shapes of galaxies for the telltale distortions caused by weak gravitational lensing and traced the growth of that signal as a function of redshift. Using both 2D and 3D analyses, we measure cosmological parameters Ω_m, the density of matter in the universe, and σ_8, the normalization of the matter power spectrum. The introduction of redshift information tightens the constraints by a factor of 3 and also reduces the relative sampling (or "cosmic") variance compared to recent surveys that may be larger but are only two-dimensional. From the 3D analysis, we find that σ_8(Ω_m/0.3)^(0.44) = 0.866^(+0.085)_(-0.068) at 68% confidence limits, including both statistical and potential systematic sources of error in the total budget. Indeed, the absolute calibration of shear measurement methods is now the dominant source of uncertainty. Assuming instead a baseline cosmology to fix the geometry of the universe, we have measured the growth of structure on both linear and nonlinear physical scales. Our results thus demonstrate a proof of concept for tomographic analysis techniques that have been proposed for future weak-lensing surveys by a dedicated wide-field telescope in space.

Item Type:Article
Related URLs:
URLURL TypeDescription DOIArticle
Massey, Richard0000-0002-6085-3780
Rhodes, Jason0000-0002-4485-8549
Leauthaud, Alexie0000-0002-3677-3617
Capak, Peter0000-0003-3578-6843
Ellis, Richard0000-0001-7782-7071
Koekemoer, Anton0000-0002-6610-2048
Scoville, Nick0000-0002-0438-3323
Kneib, Jean-Paul0000-0002-4616-4989
Additional Information:© 2007 The American Astronomical Society. Received 2006 September 22; accepted 2007 January 24. The HST COSMOS Treasury program was supported through NASA grant HST-GO-09822. The HST ACS CTE calibration program is supported through NASA grant HST-AR-10964. A. L., A. R., E. S., J. P. K., L. T., and Y. M. were partly funded by the CNRS Programme National de Cosmologie. C. H. is supported by a CITA national fellowship. We thank Alan Heavens, Tom Kitching, John Peacock, Andy Taylor, and Peter Schneider for illuminating discussions. We thank Tony Roman, Denise Taylor, and David Soderblom for their assistance in planning and scheduling the extensive COSMOS observations. We thank the NASA IPAC/ IRSA staff (Anastasia Laity, Anastasia Alexov, Bruce Berriman, and John Good) for providing online archive and server capabilities for the COSMOS data sets. It is also our pleasure to gratefully acknowledge the contributions of the entire COSMOS collaboration, consisting of more than 70 scientists. More information on the COSMOS survey is available at http://www.astro /~cosmos. Facilities:HST(ACS), Subaru (Suprime-Cam),CFHT(Megacam).
Funding AgencyGrant Number
Centre National de la Recherche Scientifique (CNRS)UNSPECIFIED
Canadian Institute for Theoretical AstrophysicsUNSPECIFIED
Subject Keywords:cosmology : observations; gravitational lensing; large-scale structure of universe
Issue or Number:1
Record Number:CaltechAUTHORS:20100211-134522689
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Official Citation:COSMOS: Three-dimensional Weak Lensing and the Growth of Structure Richard Massey, Jason Rhodes, Alexie Leauthaud, Peter Capak, Richard Ellis, Anton Koekemoer, Alexandre Réfrégier, Nick Scoville, James E. Taylor, Justin Albert, Joel Bergé, Catherine Heymans, David Johnston, Jean-Paul Kneib, Yannick Mellier, Bahram Mobasher, Elisabetta Semboloni, Patrick Shopbell, Lidia Tasca, and Ludovic Van Waerbeke 2007 ApJS 172 239-253 doi: 10.1086/516599
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:17458
Deposited By: Tony Diaz
Deposited On:16 Feb 2010 19:26
Last Modified:09 Mar 2020 13:19

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