Detecting galaxy–filament alignments in the Sloan Digital Sky Survey III

Journal Article · Tue Feb 26 00:00:00 EST 2019 · Monthly Notices of the Royal Astronomical Society

DOI:https://doi.org/10.1093/mnras/stz539· OSTI ID:1498801

Chen, Yen-Chi  ^[1]; Ho, Shirley ^[2]; Blazek, Jonathan ^[3]; He, Siyu  ^[2]; Mandelbaum, Rachel  ^[4]; Melchior, Peter  ^[5]; Singh, Sukhdeep ^[6]

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1. Department of Statistics, University of Washington, Seattle, WA 98195, USA
2. Lawrence Berkeley National Lab, Berkeley, CA 94720, USA, Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213, USA, McWilliams Center for Cosmology, Carnegie Mellon University, Pittsburgh, PA 15213, USA
3. Institute of Physics, Laboratory of Astrophysics, École Polytechnique Fédérale de Lausanne (EPFL),CH-1290 Versoix, Switzerland, Center for Cosmology and AstroParticle Physics, Department of Physics, Ohio State University, Columbus, OH 43210, USA
4. Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213, USA, McWilliams Center for Cosmology, Carnegie Mellon University, Pittsburgh, PA 15213, USA
5. Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544, USA
6. Lawrence Berkeley National Lab, Berkeley, CA 94720, USA, Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213, USA, McWilliams Center for Cosmology, Carnegie Mellon University, Pittsburgh, PA 15213, USA, Berkeley Center for Cosmological Physics and Department of Physics, University of California, Berkeley, CA 94720, USA

Abstract Previous studies have shown the filamentary structures in the cosmic web influence the alignments of nearby galaxies. We study this effect in the LOWZ sample of the Sloan Digital Sky Survey using the ‘Cosmic Web Reconstruction' filament catalogue. We find that LOWZ galaxies exhibit a small but statistically significant alignment in the direction parallel to the orientation of nearby filaments. This effect is detectable even in the absence of nearby galaxy clusters, which suggests it is an effect from the matter distribution in the filament. A non-parametric regression model suggests that the alignment effect with filaments extends over separations of 30–40 Mpc. We find that galaxies that are bright and early-forming align more strongly with the directions of nearby filaments than those that are faint and late-forming; however, trends with stellar mass are less statistically significant, within the narrow range of stellar mass of this sample.

• Sponsoring Organization: USDOE
• OSTI ID: 1498801
• Journal Information: Monthly Notices of the Royal Astronomical Society, Journal Name: Monthly Notices of the Royal Astronomical Society Vol. 485 Journal Issue: 2; ISSN 0035-8711
• Publisher: Oxford University Press
• Country of Publication: United Kingdom
• Language: English