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相关论文: An Enlarged Cosmic Shear Survey with the William H…

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The recent measurements of weak lensing by large-scale structure present significant new opportunities for studies of the matter distribution in the universe. Here, we present a new cosmic shear survey carried out with the Echelle…

天体物理学 · 物理学 2009-11-07 David Bacon , Richard Massey , Alexandre Refregier , Richard Ellis

Weak lensing by large-scale structure provides a direct measurement of matter fluctuations in the universe. We report a measurement of this `cosmic shear' based on 271 WFPC2 archival images from the Hubble Space Telescope Medium Deep Survey…

天体物理学 · 物理学 2009-06-16 A. Refregier , J. Rhodes , E. J. Groth

We report a measurement of cosmic shear correlations using an effective area of 6.5 sq. deg. of the VIRMOS deep imaging survey in progress at the Canada-France-Hawaii Telescope. We measured various shear correlation functions, the aperture…

We perform a cosmic shear analysis of the COMBO-17 survey -- a unique dataset with shear quality R-band imaging and accurate photometric redshift estimates (dz=0.05) for ~90% of galaxies to R=24.0. We undertake a full maximum likelihood…

天体物理学 · 物理学 2008-11-26 M. L. Brown , A. N. Taylor , D. J. Bacon , M. E. Gray , S. Dye , K. Meisenheimer , C. Wolf

We report a detection of the coherent distortion of faint galaxies arising from gravitational lensing by foreground structures. This ``cosmic shear'' is potentially the most direct measure of the mass power spectrum, as it is unaffected by…

天体物理学 · 物理学 2011-05-05 David Bacon , Alexandre Refregier , Richard Ellis

Weak lensing by large-scale structure allows a direct measure of the dark matter distribution. We have used parallel images taken with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope to measure weak lensing, or…

Gravitational lensing by large-scale structure induces weak coherent alignments in the shapes of background galaxies. Here we present evidence for the detection of this `cosmic shear' at the 3.4 sigma significance level with the William…

天体物理学 · 物理学 2007-05-23 David Bacon , Alexandre Refregier , Richard Ellis

Weak lensing by large-scale structure provides a unique method to directly measure matter fluctuations in the universe, and has recently been detected from the ground. Here, we report the first detection of this `cosmic shear' based on…

天体物理学 · 物理学 2009-11-06 J. Rhodes , A. Refregier , E. J. Groth

We measure the cosmic shear power spectrum on large angular scales by cross-correlating the shapes of ~9 million galaxies measured in the optical SDSS survey with the shapes of ~2.7x10^5 radio galaxies measured by the overlapping VLA-FIRST…

宇宙学与河外天体物理 · 物理学 2016-01-27 Constantinos Demetroullas , Michael L. Brown

We present the first measurement of weak lensing by large-scale structure on 1-4 degree scales based on the FIRST Radio Survey, a quarter-sky, 20-cm survey produced with the NRAO Very Large Array (VLA). The large angular scales provide an…

天体物理学 · 物理学 2009-11-10 Tzu-Ching Chang , Alexandre Refregier , David J. Helfand

Cosmic shear measurements rely on our ability to measure and correct the Point Spread Function (PSF) of the observations. This PSF is measured using stars in the field, which give a noisy measure at random points in the field. Using Wiener…

宇宙学与河外天体物理 · 物理学 2015-05-13 A. Amara , A. Refregier , S. Paulin-Henriksson

Statistical weak lensing by large-scale structure -- cosmic shear -- is a promising cosmological tool, which has motivated the design of several large upcoming surveys. Here, we present a measurement of cosmic shear using coadded Sloan…

宇宙学与河外天体物理 · 物理学 2011-12-15 Eric M. Huff , Tim Eifler , Christopher M. Hirata , Rachel Mandelbaum , David Schlegel , Uros Seljak

We present a cosmic shear analysis of the 100 square degree weak lensing survey, combining data from the CFHTLS-Wide, RCS, VIRMOS-DESCART and GaBoDS surveys. Spanning ~100 square degrees, with a median source redshift z~0.78, this combined…

Cosmological weak lensing by the large scale structure of the Universe, cosmic shear, is coming of age as a powerful probe of the parameters describing the cosmological model and matter power spectrum. It complements CMB studies, by…

天体物理学 · 物理学 2009-11-10 Patrick Simon , Lindsay J. King , Peter Schneider

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 tell-tale distortions caused by…

This paper presents the first application of 3D cosmic shear to a wide-field weak lensing survey. 3D cosmic shear is a technique that analyses weak lensing in three dimensions using a spherical harmonic approach, and does not bin data in…

We explore the stability of the variance and skewness of the cosmic gravitational convergence field, using two different approaches: first we simulate a whole MEGACAM survey (100 sq. degrees). The reconstructed mass map, obtained from a…

天体物理学 · 物理学 2007-05-23 A. Thion , Y. Mellier , F. Bernardeau , E. Bertin , T. Erben , L. van Waerbeke

Cosmic shear tomography has emerged as one of the most promising tools to both investigate the nature of dark energy and discriminate between General Relativity and modified gravity theories. In order to successfully achieve these goals,…

宇宙学与河外天体物理 · 物理学 2014-03-05 V. F. Cardone , M. Martinelli , E. Calabrese , S. Galli , Z. Huang , R. Maoli , A. Melchiorri , R. Scaramella

We present a measurement of cosmic shear on scales ranging from $ 10\arcsec $ to $ 2\arcmin $ in 347 WFPC2 images of random fields. Our result is based on shapes measured via image fitting and on a simple statistical technique; careful…

天体物理学 · 物理学 2009-11-10 Stefano Casertano , Kavan U. Ratnatunga , Richard E. Griffiths
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