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相关论文: Measuring Sigma8 with Cluster Lensing : Biases fro…

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The number density of galaxy clusters provides tight statistical constraints on the matter fluctuation power spectrum normalization, traditionally phrased in terms of sigma_8, the root mean square mass fluctuation in spheres with radius 8…

天体物理学 · 物理学 2011-02-11 J. Patrick Henry , August E. Evrard , Henk Hoekstra , Arif Babul , Andishieh Mahdavi

The abundance of clusters at the present epoch and weak gravitational lensing shear both constrain roughly the same combination of the power spectrum normalization sigma_8 and matter energy density Omega_M. The cluster constraint further…

天体物理学 · 物理学 2009-11-07 Dragan Huterer , Martin White

We develop a Maximum Likelihood estimator (MLE) to measure the masses of galaxy clusters through the impact of gravitational lensing on the temperature and polarization anisotropies of the cosmic microwave background (CMB). We show that, at…

The relation between mass and concentration of galaxy clusters traces their formation and evolution. Massive lensing clusters were observed to be over-concentrated and following a steep scaling in tension with predictions from the…

宇宙学与河外天体物理 · 物理学 2015-06-23 Mauro Sereno , Carlo Giocoli , Stefano Ettori , Lauro Moscardini

[Abridged] We present a comparison between weak-lensing (WL) and X-ray mass estimates of a sample of numerically simulated clusters. The sample consists on the 20 most massive objects at redshift z=0.25 and Mvir > 5 x 10^{14} Msun h^{-1}.…

宇宙学与河外天体物理 · 物理学 2015-06-03 E. Rasia , M. Meneghetti , R. Martino , S. Borgani , A. Bonafede , K. Dolag , S. Ettori , D. Fabjan , C. Giocoli , P. Mazzotta , J. Merten , M. Radovich , L. Tornatore

(Abridged) This is the second in a series of papers in which we derive simultaneous constraints on cosmology and X-ray scaling relations using observations of massive, X-ray flux-selected galaxy clusters. The data set consists of 238…

宇宙学与河外天体物理 · 物理学 2015-05-14 Adam Mantz , Steven W. Allen , Harald Ebeling , David Rapetti , Alex Drlica-Wagner

We forecast constraints on the amplitude of matter clustering sigma_8(z) achievable with the combination of cluster weak lensing and number counts, in current and next-generation weak lensing surveys. We advocate an approach, analogous to…

宇宙学与河外天体物理 · 物理学 2021-03-29 Hao-Yi Wu , David H. Weinberg , Andrés N. Salcedo , Benjamin D. Wibking

The use of large, X-ray selected galaxy cluster catalogues for cosmological analyses requires a thorough understanding of the X-ray mass estimates. Weak gravitational lensing is an ideal method to shed light on such issues, due to its…

宇宙学与河外天体物理 · 物理学 2017-04-05 Melanie Simet , Nicholas Battaglia , Rachel Mandelbaum , Uroš Seljak

Strong lensing has developed into an important astrophysical tool for probing both cosmology and galaxies (their structure, formation, and evolution). Using the gravitational lensing theory and cluster mass distribution model, we try to…

宇宙学与河外天体物理 · 物理学 2015-05-28 Shuo Cao , Yu Pan , Marek Biesiada , Wlodzimierz Godlowski , Zong-Hong Zhu

Evolution in the mass function of galaxy clusters sensitively traces both the expansion history of the Universe and cosmological structure formation. Robust cluster mass determinations are a key ingredient for a reliable measurement of this…

宇宙学与河外天体物理 · 物理学 2015-06-03 Holger Israel , Thomas Erben , Thomas H. Reiprich , Alexey Vikhlinin , Craig L. Sarazin , Peter Schneider

We present weak lensing results for 12 distant clusters determined from images obtained with the refurbished HST. We detect the signature of gravitational lensing in 11 of the 12 clusters; the clusters span nearly an order of magnitude in…

The Local Cluster Substructure Survey (LoCuSS, Smith et al.) is a systematic multi-wavelength survey of >100 X-ray luminous galaxy clusters (0.14<z<0.3) selected from the ROSAT all sky survey. We used data on 37 LoCuSS clusters from the…

天体物理学 · 物理学 2009-11-13 Y. -Y. Zhang , A. Finoguenov , H. Boehringer , J. -P. Kneib , G. P. Smith , R. Kneissl , N. Okabe , H. Dahle

The mass derived from gravitational lensing reflects the total mass contained in the lensing system, independent of the specific matter contents and states. A comparison of the dynamical masses from hydrostatic equilibrium with the…

天体物理学 · 物理学 2009-10-22 Xiang-Ping Wu

Using numerical simulations of cluster formation in the standard CDM model (SCDM) and in a low-density, flat CDM model with a cosmological constant (LCDM), we investigate the gravitational lensing explanation for the reported associations…

天体物理学 · 物理学 2009-10-30 Xiang-Ping Wu , Xiao-Hong Zhu , Yi-Peng Jing , Li-Zhi Fang

We use giga-particle N-body simulations to study galaxy cluster populations in Hubble Volumes of LCDM (Omega_m=0.3, Omega_Lambda=0.7) and tCDM (Omega_m=1) world models. Mapping past light-cones of locations in the computational space, we…

Weak-lensing measurements of the averaged shear profiles of galaxy clusters binned by some proxy for cluster mass are commonly converted to cluster mass estimates under the assumption that these cluster stacks have spherical symmetry. In…

We present weak lensing and X-ray analysis of 12 low mass clusters from the CFHTLenS and XMM-CFHTLS surveys. We combine these systems with high-mass systems from CCCP and low-mass systems from COSMOS to obtain a sample of 70 systems,…

Gravitational lensing magnification is measured with a significance of 9.7 sigma on a large sample of galaxy clusters in the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS). This survey covers ~154 deg^2 and contains over 18,000…

宇宙学与河外天体物理 · 物理学 2014-03-05 Jes Ford , Hendrik Hildebrandt , Ludovic Van Waerbeke , Thomas Erben , Clotilde Laigle , Martha Milkeraitis , Christopher Morrison

We present a detailed investigation into which properties of CDM halos make them effective strong gravitational lenses. Strong lensing cross sections of 878 clusters from an N-body simulation are measured by ray tracing through 13,594…

天体物理学 · 物理学 2008-11-26 Joseph F. Hennawi , Neal Dalal , Paul Bode , Jeremiah P. Ostriker