Cores and Cusps in Warm Dark Matter Halos

TL;DR

This paper demonstrates that warm dark matter halos do not naturally form large cores, implying that observed large cores in galaxies likely have astrophysical origins rather than being due to warm dark matter properties.

Contribution

The study provides quantitative analysis showing that warm dark matter halos have very small cores, challenging previous claims and suggesting alternative explanations for observed galaxy cores.

Findings

WDM halos have core radii less than 0.1% of the halo size

Large observed galaxy cores are unlikely to be caused by warm dark matter

Astrophysical processes are more probable origins for large galaxy cores

Abstract

The apparent presence of large core radii in Low Surface Brightness galaxies has been claimed as evidence in favor of warm dark matter. Here we show that WDM halos do not have cores that are large fractions of the halo size: typically, r_core/r_200 < 0.001. This suggests an astrophysical origin for the large cores observed in these galaxies, as has been argued by other authors.