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Related papers: On Arcs and Omega

200 papers

We use a high-resolution $N$-body simulation to investigate the influence of background galaxy properties, including redshift, size, shape and clustering, on the efficiency of forming giant arcs by gravitational lensing of rich galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 G. J. Gao , Y. P. Jing , S. Mao , G. L. Li , X. Kong

The frequency with which background galaxies appear as long arcs as a result of gravitational lensing by foreground clusters of galaxies has recently been found to be a very sensitive probe of cosmological models by Bartelmann et al.…

Astrophysics · Physics 2009-10-31 R. A. Flores , A. H. Maller , J. R. Primack

The morphology of galaxy clusters reflects the epoch at which they formed and hence depends on the value of the mean cosmological density, Omega. Recent studies have shown that the distribution of dark matter in clusters can be mapped from…

Astrophysics · Physics 2015-06-24 Gillian Wilson , Shaun Cole , Carlos S. Frenk

We compare the statistical properties of giant gravitationally lensed arcs produced in matched simulated and observed cluster samples. The observed sample consists of 10 X-ray selected clusters at redshifts z ~ 0.2 imaged with HST by Smith…

We use numerical simulations of galaxy clusters in different cosmologies to study their ability to form large arcs. The cosmological models are: Standard CDM (SCDM; Omega_0=1, Omega_Lambda=0); tauCDM with reduced small-scale power…

We study the strong gravitational lensing properties of galaxy clusters obtained from N-body simulations with standard $\Lambda$CDM cosmology. We have used the 32 most massive clusters from a simulation at various redshifts and ray-traced…

Astrophysics · Physics 2008-11-26 Shirley Ho , Martin White

We use semi-analytic modelling of the galaxy-cluster population and its strong lensing efficiency to explore how the expected abundance of large gravitational arcs on the sky depends on $\sigma_8$. Our models take all effects into account…

Astrophysics · Physics 2009-06-23 C. Fedeli , M. Bartelmann , M. Meneghetti , L. Moscardini

We use current observations on the number statistics of gravitationally lensed optical arcs towards galaxy clusters to derive an upper limit on the cosmological mass density of the Universe. The gravitational lensing statistics due to…

Astrophysics · Physics 2009-10-31 Asantha R. Cooray

We study the efficiency of numerically simulated galaxy clusters for producing strong gravitational lensing events in different dark-energy cosmologies with constant and time-variable equation of state and we compare it with ``standard''…

It is shown in this paper that deviations of galaxy cluster lenses from spherical symmetry can render mass estimates for galaxy clusters based on the formation of large arcs systematically to high. Numerical models show that the mass needed…

Astrophysics · Physics 2011-05-23 Matthias Bartelmann

We present an estimation of the expected number of arcs and arclets in a sample of nearby (z<0.1) clusters of galaxies, that takes into account the magnitude limit of the objects as well as seeing effects. We show that strong lensing…

It has been debated for a decade whether there is a large overabundance of strongly lensed arcs in galaxy clusters, compared to expectations from LambdaCDM cosmology. We perform ray tracing through the most massive halos of the Millennium…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Assaf Horesh , Dan Maoz , Stefan Hilbert , Matthias Bartelmann

We developed an algorithm to find and characterize gravitationally lensed galaxies (arcs) to perform a comparison of the observed and simulated arc abundance. Observations are from the Cluster Lensing And Supernova survey with Hubble…

We investigate how ellipticity, asymmetries and substructures separately affect the ability of galaxy clusters to produce strong lensing events, i.e. gravitational arcs, and how they influence the arc morphologies and fluxes. This is…

We calculate the expected number of gravitationally lensed optical, radio and sub-mm lensed sources on the whole sky due to foreground galaxy clusters for different cosmological models. We improve previous calculations of lensed arc…

Astrophysics · Physics 2011-05-23 Asantha R. Cooray

In a flat, k=0 cosmology with galaxies that approximate singular isothermal spheres, gravitational lens image separations should be uncorrelated with source redshift. But in an open k=-1 cosmology such gravitational lens image separations…

Astrophysics · Physics 2009-10-30 Myeong-Gu Park , J. Richard Gott

We construct a sample of numerical models for clusters of galaxies and employ these to investigate their capability of imaging background sources into long arcs. Emphasis is laid on the statistics of these arcs. We study cross sections for…

Astrophysics · Physics 2007-05-23 Matthias Bartelmann , Matthias Steinmetz , Achim Weiss

The statistics of strongly lensed arcs in samples of galaxy clusters provide information on cluster structure that is complementary to that from individual clusters. However, samples of clusters that have been analyzed to date have been…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Assaf Horesh , Dan Maoz , Harald Ebeling , Gregor Seidel , Matthias Bartelmann

We use high-resolution N-body simulations to study the galaxy-cluster cross-sections and the abundance of giant arcs in the $\Lambda$CDM model. Clusters are selected from the simulations using the friends-of-friends method, and their…

Astrophysics · Physics 2009-11-10 G. L. Li , S. Mao , Y. P. Jing , M. Bartelmann , X. Kang , M. Meneghetti

Galaxy clusters have their unique advantages for cosmology. Here we collect a new sample of 10 lensing galaxy clusters with X-ray observations to constrain cosmological parameters.The redshifts of lensing clusters lie between 0.1 and 0.6,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Heng Yu , Zong-Hong Zhu
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