Journal Article

Multimass spherical structure models for <i>N</i>-body simulations

Marcel Zemp, Ben Moore, Joachim Stadel, C. Marcella Carollo and Piero Madau

in Monthly Notices of the Royal Astronomical Society

Published on behalf of The Royal Astronomical Society

Volume 386, issue 3, pages 1543-1556
Published in print May 2008 | ISSN: 0035-8711
Published online April 2008 | e-ISSN: 1365-2966 | DOI:
Multimass spherical structure models for N-body simulations

More Like This

Show all results sharing this subject:

  • Astronomy and Astrophysics


Show Summary Details


We present a simple and efficient method to set up spherical structure models for N-body simulations with a multimass technique. This technique reduces by a substantial factor the computer run time needed in order to resolve a given scale as compared to single-mass models. It therefore allows to resolve smaller scales in N-body simulations for a given computer run time. Here, we present several models with an effective resolution of up to 1.68 × 109 particles within their virial radius which are stable over cosmologically relevant time-scales. As an application, we confirm the theoretical prediction by Dehnen that in mergers of collisionless structures like dark matter haloes always the cusp of the steepest progenitor is preserved. We model each merger progenitor with an effective number of particles of approximately 108 particles. We also find that in a core–core merger the central density approximately doubles whereas in the cusp–cusp case the central density only increases by approximately 50 per cent. This may suggest that the central regions of flat structures are better protected and get less energy input through the merger process.

Keywords: methods: N-body simulations; methods: numerical

Journal Article.  7799 words.  Illustrated.

Subjects: Astronomy and Astrophysics

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.