Cookies

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:

N-body dark matter haloes with simple hierarchical histories.

Jiang, Lilian and Helly, John and Cole, Shaun and Frenk, Carlos S. (2014) 'N-body dark matter haloes with simple hierarchical histories.', Monthly notices of the Royal Astronomical Society., 440 (3). pp. 2115-2135.

Abstract

We present a new algorithm which groups the subhaloes found in cosmological N-body simulations by structure finders such as SUBFIND into dark matter haloes whose formation histories are strictly hierarchical. One advantage of these `Dhaloes' over the commonly used friends-of-friends (FoF) haloes is that they retain their individual identity in the cases when FoF haloes are artificially merged by tenuous bridges of particles or by an overlap of their outer diffuse haloes. Dhaloes are thus well suited for modelling galaxy formation and their merger trees form the basis of the Durham semi-analytic galaxy formation model, GALFORM. Applying the Dhalo construction to the Λ cold dark matter Millennium II Simulation, we find that approximately 90 per cent of Dhaloes have a one-to-one, bijective match with a corresponding FoF halo. The remaining 10 per cent are typically secondary components of large FoF haloes. Although the mass functions of both types of haloes are similar, the mass of Dhaloes correlates much more tightly with the virial mass, M200, than FoF haloes. Approximately 80 per cent of FoF and bijective and non-bijective Dhaloes are relaxed according to standard criteria. For these relaxed haloes, all three types have similar concentration-M200 relations and, at fixed mass, the concentration distributions are described accurately by log-normal distributions.

Item Type:Article
Keywords:Methods: numerical, Galaxies: haloes, Cosmology: theory, Dark matter.
Full text:(VoR) Version of Record
Download PDF
(3031Kb)
Status:Peer-reviewed
Publisher Web site:http://dx.doi.org/10.1093/mnras/stu390
Publisher statement:This article has been published in the Monthly Notices of the Royal Astronomical Society. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
Date accepted:24 February 2014
Date deposited:14 April 2014
Date of first online publication:04 April 2014
Date first made open access:No date available

Save or Share this output

Export:
Export
Look up in GoogleScholar