Galaxy assembly bias: a significant source of systematic error in the galaxy–halo relationship
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In this paper, the authors estimate the potential for assembly bias to induce systematic errors in inferred halo occupation statistics and conclude that the galaxy-halo relationship inferred from galaxy clustering should be subject to a non-negligible systematic error induced by assembly bias.Abstract:
It is common practice for methods that use galaxy clustering to constrain the galaxy-halo relationship, such as the halo occupation distribution (HOD) and/or conditional luminosity function (CLF), to assume that halo mass alone suffices to determine a halo's resident galaxy population. Yet, the clustering strength of cold dark matter halos depends upon halo properties in addition to mass, such as formation time, an effect referred to as assembly bias. If galaxy characteristics are correlated with any of these auxiliary halo properties, the basic assumption of HOD/CLF methods is violated. We estimate the potential for assembly bias to induce systematic errors in inferred halo occupation statistics. We use halo abundance matching and age matching to construct fiducial mock galaxy catalogs that exhibit assembly bias as well as additional mock catalogs with identical HODs, but with assembly bias removed. We fit a parameterized HOD to the projected two-point clustering of mock galaxies in each catalog to assess the systematic errors induced by reasonable levels of assembly bias. In the absence of assembly bias, the inferred HODs generally describe the true underlying HODs well, validating the basic methodology. However, in all of the cases with assembly bias, the inferred HODs have systematic errors that are statistically significant. In most cases, these systematic errors cannot be identified using void statistics as auxiliary observables. We conclude that the galaxy-halo relationship inferred from galaxy clustering should be subject to a non-negligible systematic error induced by assembly bias. Our work suggests that efforts to model and/or constrain assembly bias should be high priorities as it is a threatening source of systematic error in galaxy evolution studies as well as the precision cosmology program.read more
Citations
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References
More filters
Journal ArticleDOI
A Universal Density Profile from Hierarchical Clustering
TL;DR: In this article, the authors used high-resolution N-body simulations to study the equilibrium density profiles of dark matter halos in hierarchically clustering universes, and they found that all such profiles have the same shape, independent of the halo mass, the initial density fluctuation spectrum, and the values of the cosmological parameters.
Journal ArticleDOI
Formation of Galaxies and Clusters of Galaxies by Self-Similar Gravitational Condensation
Journal ArticleDOI
Core condensation in heavy halos: a two-stage theory for galaxy formation and clustering
Simon D. M. White,Martin J. Rees +1 more
Journal ArticleDOI
The 2dF Galaxy Redshift Survey: spectra and redshifts
Matthew Colless,Gavin Dalton,Stephen J. Maddox,William J. Sutherland,Peder Norberg,Shaun Cole,Joss Bland-Hawthorn,Terry J. Bridges,Russell D. Cannon,Chris A. Collins,Warrick J. Couch,Nicholas Cross,K. Deeley,Roberto De Propris,Simon P. Driver,George Efstathiou,Richard S. Ellis,Carlos S. Frenk,Karl Glazebrook,Carole Jackson,Ofer Lahav,Ian Lewis,Stuart Lumsden,Darren Madgwick,John A. Peacock,Bruce A. Peterson,Ian Price,M. Seaborne,Keith Taylor +28 more
TL;DR: The 2dF Galaxy Redshift Survey (2dFGRS) as mentioned in this paper uses the 2DF multifibre spectrograph on the Anglo-Australian Telescope, which is capable of observing 400 objects simultaneously over a 2° diameter field.
Journal ArticleDOI
Merger rates in hierarchical models of galaxy formation
Cedric G. Lacey,Shaun Cole +1 more
TL;DR: In this article, an analytical description of the merging of virialized haloes is presented, which is applicable to any hierarchical model in which structure grows via gravitational instability, and the dependence of the merger rate on halo mass, epoch, the spectrum of initial density fluctuations and the density parameter Ω 0 is explicitly quantified.
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