Estimate of dark halo ellipticity by lensing flexion
نویسندگان
چکیده
منابع مشابه
A Detection of Dark Matter Halo Ellipticity Using Galaxy Cluster Lensing in Sdss
We measure the ellipticity of isolated clusters of galaxies in the Sloan Digital Sky Survey (SDSS) using gravitational lensing. We stack the clusters, rotating so that the major axes of the ellipses determined by the positions of cluster member galaxies are aligned. We exclude the signal from the central 0.5 h Mpc to avoid problems with stacking alignment and cluster member contamination. We fi...
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We investigate the influence of the inner profile of the lens objects on gravitational lensing statistics taking into account of the effect of the magnification bias and both the evolution and the scatter of halo profiles. We take the dark matter halos as the lens objects and consider the following three models for the density profile of the dark matter halo; SIS (singular isothermal sphere), t...
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Although current methods exist to predict the location of these centers given comprehensive amounts of data such as three-dimensional position, mass, etc., there are not many approaches to finding the centers given two-dimensional images of a sky. However, for many regions of space, the only data collected are two-dimensional images, and thus the dark matter structures in those regions of space...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2011
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361/201015766