Non-parametric uncertainties in the dark matter velocity distribution

Dark matter distribution in the Draco dwarf from velocity moments

We study the distribution of dark matter in the Draco dwarf spheroidal galaxy by modelling the moments of the line-of-sight velocity distribution of stars obtained from new velocity data of Wilkinson et al. The luminosity distribution is approximated by a Sérsic profile fitted to the data by Odenkirchen et al. We assume that the dark matter density profile is given by a formula with inner cusp ...

Dark Matter Velocity Spectroscopy.

Dark matter decays or annihilations that produce linelike spectra may be smoking-gun signals. However, even such distinctive signatures can be mimicked by astrophysical or instrumental causes. We show that velocity spectroscopy-the measurement of energy shifts induced by relative motion of source and observer-can separate these three causes with minimal theoretical uncertainties. The principal ...

Velocity fields in non–Gaussian cold dark matter models

We analyse the large–scale velocity field obtained by N–body simulations of cold dark matter (CDM) models with non–Gaussian primordial density fluctuations, considering models with both positive and negative primordial skewness in the density fluctuation distribution. We study the velocity probability distribution and calculate the dependence of the bulk flow, one–point velocity dispersion and ...

Uncertainties in Dark Matter Indirect Detection

Velocity Dispersion Profile in Dark Matter Halos

Numerous numerical studies indicate that dark matter halos show an almost universal radial density profile. The origin of the profile is still under debate. We investigate this topic and pay particular attention to the velocity dispersion profile. To this end we have performed high-resolution simulations with two independent codes, ART and Gadget. The radial velocity dispersion can be approxima...