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arXiv · 1909.05852

A gravitational lensing detection of filamentary structures connecting luminous red galaxies

Qianli Xia·Naomi Robertson·Catherine Heymans·Alexandra Amon·Marika Asgari·Yan-Chuan Cai·Thomas Erben·Joachim Harnois-Déraps·Hendrik Hildebrandt·Arun Kannawadi·Konrad Kuijken·Peter Schneider·Cristóbal Sifón·Tilman Tröster·Angus H. Wright
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Abstract

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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Qianli Xia, Naomi Robertson, Catherine Heymans, Alexandra Amon, Marika Asgari, Yan-Chuan Cai, Thomas Erben, Joachim Harnois-Déraps, Hendrik Hildebrandt, Arun Kannawadi, Konrad Kuijken, Peter Schneider, Cristóbal Sifón, Tilman Tröster, Angus H. Wright. 2019-09-12. A gravitational lensing detection of filamentary structures connecting luminous red galaxies. https://doi.org/10.1051/0004-6361%2F201936678

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