English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The free streaming of warm dark matter particles dampens the fluctuation spectrum, flattens the mass function of haloes and sets a fine‐grained phase density limit for dark matter structures. The phase‐space density limit is expected to imprint a constant‐density core at the halo centre in contrast to what happens for cold dark matter. We explore these effects using high‐resolution simulations of structure formation in different warm dark matter scenarios. We find that the size of the core we obtain in simulated haloes is in good agreement with theoretical expectations based on Liouville’s theorem. However, our simulations show that in order to create a significant core ( kpc) in a dwarf galaxy ( M ∼ 10 10  M ⊙ ), a thermal candidate with mass as low as 0.1 keV is required. This would fully prevent the formation of the dwarf galaxy in the first place. For candidates satisfying large‐scale structure constraints ( m  ν  larger than ≈1–2 keV), the expected size of the core is of the order of 10 (20) pc for a dark matter halo with a mass of 10 10  (10 8 ) M ⊙ . We conclude that ‘standard’ warm dark matter is not a viable solution for explaining the presence of cored density profiles in low‐mass galaxies.

Cores in warm dark matter haloes: a Catch 22 problem