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

We study the abundance of subhaloes in the hydrodynamical cosmologicalsimulation Illustris, which includes both baryons and dark matter in a$\Lambda$CDM volume 106.5 Mpc a side. We compare Illustris to its darkmatter-only (DMO) analogue, Illustris-Dark, and quantify the effects ofbaryonic processes on the demographics of subhaloes in the host mass range$10^{11}$ to $3 \times 10^{14} \msun$. We focus on both the evolved ($z=0$)subhalo cumulative mass functions (SHMF) and the statistics of subhaloes everaccreted, i.e. infall subhalo mass function. We quantify the variance insubhalo abundance at fixed host mass and investigate the physical reasonsresponsible for such scatter. We find that in Illustris, baryonic physicsimpacts both the infall and $z=0$ subhalo abundance by tilting the DMO functionand suppressing the abundance of low-mass subhaloes. The breaking ofself-similarity in the subhalo abundance at $z=0$ is enhanced by the inclusionof baryonic physics. The non-monotonic alteration of the evolved subhaloabundances can be explained by the modification of the concentration--massrelation of Illustris hosts compared to Illustris-Dark.Interestingly, thebaryonic implementation in Illustris does not lead to an increase in thehalo-to-halo variation compared to Illustris-Dark. In both cases, thenormalized intrinsic scatter today is larger for Milky Way-like haloes than forcluster-sized objects. For Milky Way-like haloes, it increases from about eightper cent at infall to about 25 per cent at the current epoch. In both runs,haloes of fixed mass formed later host more subhaloes than early formers.

Subhalo Demographics in the Illustris Simulation: Effects of Baryons and Halo-to-Halo Variation