Can intrinsic alignments of elongated low-mass galaxies be used to map the cosmic web at high redshift?
Author
Pandya, Viraj
Primack, Joel
Behroozi, Peter
Dekel, Avishai

Zhang, Haowen
Eckholm, Elliot
Faber, Sandra M
Ferguson, Henry C
Giavalisco, Mauro

Guo, Yicheng

Hathi, Nimish

Kodra, Dritan
Koekemoer, Anton M
Koo, David C
Newman, Jeffrey
van der Wel, Arjen
Affiliation
Univ Arizona, Dept AstronUniv Arizona, Steward Observ
Issue Date
2019-08-02Keywords
galaxies: dwarfgalaxies: high-redshift
galaxies: statistics
galaxies: structure
dark matter
large-scale structure of Universe
Metadata
Show full item recordPublisher
OXFORD UNIV PRESSCitation
Viraj Pandya, Joel Primack, Peter Behroozi, Avishai Dekel, Haowen Zhang, Elliot Eckholm, Sandra M Faber, Henry C Ferguson, Mauro Giavalisco, Yicheng Guo, Nimish Hathi, Dritan Kodra, Anton M Koekemoer, David C Koo, Jeffrey Newman, Arjen van der Wel, Can intrinsic alignments of elongated low-mass galaxies be used to map the cosmic web at high redshift?, Monthly Notices of the Royal Astronomical Society, Volume 488, Issue 4, October 2019, Pages 5580–5593, https://doi.org/10.1093/mnras/stz2129Rights
Copyright © 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society.Collection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.Abstract
Hubble Space Telescope observations show that low-mass () galaxies at high redshift (z= 1.0-2.5) tend to be elongated (prolate) rather than disky (oblate) or spheroidal. This is explained in zoom-in cosmological hydrodynamical simulations by the fact that these galaxies are forming in cosmic web filaments where accretion happens preferentially along the direction of elongation. We ask whether the elongated morphology of these galaxies allows them to be used as effective tracers of cosmic web filaments at high redshift via their intrinsic alignments. Using mock light cones and spectroscopically confirmed galaxy pairs from the Cosmic Assembly Near-infared Deep Extragalactic Legacy Survey (CANDELS), we test two types of alignments: (1) between the galaxy major axis and the direction to nearby galaxies of any mass and (2) between the major axes of nearby pairs of low-mass, likely prolate, galaxies. The mock light cones predict strong signals in 3D real space, 3D redshift space, and 2D projected redshift space for both types of alignments (assuming prolate galaxy orientations are the same as those of their host prolate haloes), but we do not detect significant alignment signals in CANDELS observations. However, we show that spectroscopic redshifts have been obtained for only a small fraction of highly elongated galaxies, and accounting for spectroscopic incompleteness and redshift errors significantly degrades the 2D mock signal. This may partly explain the alignment discrepancy and highlights one of several avenues for future work.ISSN
0035-8711Version
Final published versionSponsors
National Science FoundationNational Science Foundation (NSF) [1339067]; NASA from the Space Telescope Science Institute [HST-AR-14578.001-A]; NASANational Aeronautics & Space Administration (NASA) [NAS 5-26555]ae974a485f413a2113503eed53cd6c53
10.1093/mnras/stz2129