Search arXiv⌕ Search

arXiv · 1402.7073

Cold dark matter haloes in the Planck era: evolution of structural parameters for Einasto and NFW profiles

Abstract

We present the evolution of the structure of relaxed cold dark matter haloes in the cosmology from the Planck satellite. Our simulations cover 5 decades in halo mass, from dwarf galaxies to galaxy clusters. Due to the increased matter density and power spectrum normalization the concentration mass relation in the Planck cosmology has a 20 percent higher normalization at redshift z=0 compared to WMAP cosmology. We confirm that CDM haloes are better described by the Einasto profile; for example, at scales near galaxy half-light radii CDM haloes have significantly steeper density profiles than implied by NFW fits. There is a scatter of 0.2 dex in the Einasto shape parameter at fixed halo mass, adding further to the diversity of CDM halo profiles. The evolution of the concentration mass relation in our simulations is not reproduced by any of the analytic models in the literature. We thus provide a simple fitting formula that accurately describes the evolution between redshifts z=5 to z=0 for both NFW and Einasto fits. Finally, the observed concentrations and halo masses of spiral galaxies, groups and clusters of galaxies at low redshifts are in good agreement with our simulations, suggesting only mild halo response to galaxy formation on these scales.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Aaron A. Dutton, Andrea V. Macciò. 2014-04-29. Cold dark matter haloes in the Planck era: evolution of structural parameters for Einasto and NFW profiles. https://doi.org/10.1093/mnras%2Fstu742

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Vacuum Polarization, Geodesic Equation and Sachs-Wolfe Effect

We show that the null geodesic equation for photons is modified in the presence of a charged scalar field, with quantum fluctuations acting as an effective mass term that changes the null paths to timelike curves. This effect can be interpreted as a vacuum polarization phenomenon in curved spacetime. The resulting contribution to the Sachs-Wolfe effect varies with photon frequency, leading to frequency-dependent corrections to the cosmic microwave background (CMB) blackbody spectrum in the form of a $μ$-distortion, as well as modifications to the CMB power spectrum. We estimate these within a standard inflationary scenario and find that while the correction to the CMB power spectrum is significant when the scalar field is light, the magnitude of the $μ$-distortion depends strongly on the regularization prescription.

astro-ph.CO↗

Testing Bump in the Cosmological Power Spectrum Using Dwarf Galaxies

We analyze the possibility of using observational data on nearby dwarf galaxies -- their luminosity functions and spatial distributions -- to constrain deviations of the cosmological power spectrum from the standard one. Specifically, we consider a cosmological model with a "bump" in the power spectrum at a wavelength of 1.3~Mpc and a dimensionless amplitude $\mathcal{A}=2.0$. Such a spectrum is motivated by observations of an excess number of galaxies at high redshifts. The bump leads to a noticeable increase in the luminosity function in the range $-13 > M_B > -17$ at $z=0$. Comparison with observations constrains the bump amplitude to $\mathcal{A} < 0.25$ at a 3-sigma significance level for a wavelength of 1.3~Mpc. For wavelengths smaller than 0.8~Mpc, the bump manifests only in the luminosity function of dwarfs with $M_B > -14$.

astro-ph.CO↗

Multi-tracers, multi-surveys: a joint Fisher analysis of DESI+PFS

Marginalizing over 11 effective-field-theory (EFT) nuisance parameters per tracer per redshift bin degrades cosmological precision in one-loop analyses of galaxy power-spectrum multipoles in redshift space. Simulation-based priors (SBP) tighten these parameters but rely on N-body simulations and halo-occupation-distribution (HOD) models. We consider a multi-tracer Fisher analysis as a complementary approach: auto- and cross-power spectra jointly constrain cosmology, galaxy bias and stochasticity through two channels -- within a survey and across overlapping surveys -- combined in a volume-partitioned joint Fisher analysis. We forecast across the $14{,}000\;\mathrm{deg}^2$ Dark Energy Spectroscopic Instrument (DESI) footprint, including the $\sim\!1{,}200\;\mathrm{deg}^2$ Prime Focus Spectrograph (PFS) overlap at $z\in[0.6,1.6]$ with up to 4 tracers (PFS-ELG, DESI-ELG, DESI-LRG, DESI-QSO). We vary a common $\ln(10^{10}A_s)$, $M_ν$ and $Ω_m$, holding $h$, $ω_b$ and $n_s$ fixed. Adding internal-DESI cross-spectra to DESI auto-spectra reduces the errors on the derived $fσ_8(z=1.1)$, $M_ν$ and $Ω_m$ by 7.1%, 3.5% and 3.8%, respectively, at $k_{\rm max}=0.20\,h\,\mathrm{Mpc}^{-1}$. Adding PFS auto- and cross-spectra to this complete DESI multi-tracer analysis further tightens these errors by 3.8%, 2.6% and 3.2%, respectively, after marginalizing over residual cross-population stochasticity. The clustering likelihood alone constrains the linear and quadratic biases and the shot noise. For these parameters it provides a complementary test of inference using SBP, while the counterterms remain weakly constrained. The framework extends to any number of overlapping spectroscopic surveys.

astro-ph.CO↗