2002/06/28 by Matthias Bartelmann, F. Perrotta, Francesca Perrotta +2 · 6 citations
Physics and Astronomy · #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Galaxies: Formation, Evolution, Phenomena #astro-ph
paper · pdf · doi:10.1051/0004-6361:20021417
published as Astron.Astrophys. 396 (2002) 21-30 · 8 pages, 9 figures included
arxiv created 2002/06/28 · openalex publication_date 2002/11/22 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
We study the effects of a dark energy component with equation of state with constant on the formation of Cold Dark Matter (CDM) haloes. We find two main effects: first, haloes form earlier as w increases, and second, the amplitude of the dark-matter power spectrum gets reduced in order to remain compatible with the large scale Cosmic Microwave Background (CMB) anisotropies. These effects counteract. Using recipes derived from numerical simulations, we show that haloes are expected to be up to ~50% more concentrated in CDM models with quintessence compared to ΛCDM models, the maximum increase being reached for . For larger w, the amplitude of the power spectrum decreases rapidly and makes expected halo concentrations decrease. Halo detections through weak gravitational lensing are highly sensitive to halo concentrations. We show that weak-lensing halo counts with the aperture-mass technique increase by a factor of ~2 as w is increased from -1 to -0.6, offering a new method for constraining the nature of dark energy.