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تسجيل مستخدم جديدA gravitational lensing detection of filamentary structures connecting luminous red galaxies
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We present a weak lensing detection of filamentary structures in the cosmic web, combining data from the Kilo-Degree Survey, the Red Cluster Sequence Lensing Survey and the Canada-France-Hawaii Telescope Lensing Survey. The line connecting luminous red galaxies with a separation of $3 - 5, h^{-1}text{Mpc}$ is chosen as a proxy for the location of filaments. We measure the average weak lensing shear around $sim$11,000 candidate filaments selected in this way from the Sloan Digital Sky Survey. After nulling the shear induced by the dark matter haloes around each galaxy, we report a $3.4,sigma$ detection of an anisotropic shear signal from the matter that connects them. Adopting a filament density profile, motivated from $N$-body simulations, the average density at the centre of these filamentary structures is found to be $15 pm 4$ times the critical density.
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