We use cookies to ensure that we give you the best experience on our website. By continuing to browse this repository, you give consent for essential cookies to be used. You can read more about our Privacy and Cookie Policy.

Durham Research Online
You are in:

The clustering of dark matter haloes : scale-dependent bias on quasi-linear scales.

Jose, C. and Lacey, C. G. and Baugh, C. M. (2016) 'The clustering of dark matter haloes : scale-dependent bias on quasi-linear scales.', Monthly notices of the Royal Astronomical Society., 463 (1). pp. 270-281.


We investigate the spatial clustering of dark matter halos, collapsing from 1 − 4σ fluctuations, in the redshift range 0 − 5 using N-body simulations. The halo bias of high redshift halos (z ≥ 2) is found to be strongly non-linear and scale-dependent on quasi-linear scales that are larger than their virial radii (0.5 − 10 Mpc/h). However, at lower redshifts, the scale-dependence of non-linear bias is weaker and and is of the order of a few percent on quasi-linear scales at z ∼ 0. We find that the redshift evolution of the scale dependent bias of dark matter halos can be expressed as a function of four physical parameters: the peak height of halos, the non-linear matter correlation function at the scale of interest, an effective power law index of the rms linear density fluctuations and the matter density of the universe at the given redshift. This suggests that the scale-dependence of halo bias is not a universal function of the dark matter power spectrum, which is commonly assumed. We provide a fitting function for the scale dependent halo bias as a function of these four parameters. Our fit reproduces the simulation results to an accuracy of better than 4% over the redshift range 0 ≤ z ≤ 5. We also extend our model by expressing the non-linear bias as a function of the linear matter correlation function. It is important to incorporate our results into the clustering models of dark matter halos at any redshift, including those hosting early generations of stars and galaxies before reionization.

Item Type:Article
Full text:(VoR) Version of Record
Download PDF
Publisher Web site:
Publisher statement:This article has been published in Monthly Notices of the Royal Astronomical Society ©: 2016 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
Date accepted:13 July 2016
Date deposited:06 October 2016
Date of first online publication:18 July 2016
Date first made open access:06 October 2016

Save or Share this output

Look up in GoogleScholar