Simulations of deep pencil-beam redshift surveys

Yoshida, N, Colberg, J, White, S D M, Evrard, A E, MacFarland, T J, Couchman, H M P, Jenkins, A, Frenk, C S, Pearce, F R, Efstathiou, G, Peacock, J A and Thomas, P A (2001) Simulations of deep pencil-beam redshift surveys. Monthly Notices of the Royal Astronomical Society, 325 (2). pp. 803-816. ISSN 0035-8711

[img]
Preview
PDF - Published Version
Download (1MB) | Preview

Abstract

We create mock pencil-beam redshift surveys from very large cosmological N-body simulations of two cold dark matter (CDM) cosmogonies, an Einstein-de Sitter model (tau CDM) and a flat model with Ohm (0) = 0.3 and a cosmological constant (Lambda CDM). We use these to assess the significance of the apparent periodicity discovered by Broadhurst et al. Simulation particles are tagged as 'galaxies' so as to reproduce observed present-day correlations. They are then identified along the past light-cones of hypothetical observers to create mock catalogues with the geometry and the distance distribution of the Broadhurst et al. data. We produce 1936 (2625) quasi-independent catalogues from our tau CDM (Lambda CDM) simulation. A couple of large clumps in a catalogue can produce a high peak at low wavenumbers in the corresponding one-dimensional power spectrum, without any apparent large-scale periodicity in the original redshift histogram. Although the simulated redshift histograms frequently display regularly spaced clumps, the spacing of these clumps varies between catalogues and there is no 'preferred' period over our many realizations. We find only a 0.72 (0.49) per cent chance that the highest peak in the power spectrum of a tau CDM (Lambda CDM) catalogue has a peak-to-noise ratio higher than that in the Broadhurst et al. data. None of the simulated catalogues with such high peaks shows coherently spaced clumps with a significance as high as that of the real data. We conclude that in CDM universes, the regularity on a scale of similar to 130 h(-1) Mpc observed by Broadhurst et al. has a priori probability well below 10(-3).

Item Type: Article
Additional Information: White, S. D. M.; Evrard, A. E.; MacFarland, T. J.; Couchman, H. M. P.; Jenkins, A.; Frenk, C. S.; Pearce, F. R.; Efstathiou, G.; Peacock, J. A.
Schools and Departments: School of Mathematical and Physical Sciences > Physics and Astronomy
Depositing User: EPrints Services
Date Deposited: 06 Feb 2012 21:08
Last Modified: 07 Mar 2017 08:23
URI: http://sro.sussex.ac.uk/id/eprint/29727

View download statistics for this item

📧 Request an update