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

Using hydrodynamical simulations, we study how well the underlyinggravitational potential of a galaxy cluster can be modelled dynamically withdifferent types of tracers. In order to segregate different systematics and theeffects of varying estimator performances, we first focus on applying a genericminimal assumption method (oPDF) to model the simulated haloes using the full6-D phasespace information. We show that the halo mass and concentration can berecovered in an ensemble unbiased way, with a stochastic bias that varies fromhalo to halo, mostly reflecting deviations from steady state in the tracerdistribution. The typical systematic uncertainty is $\sim 0.17$ dex in thevirial mass and $\sim 0.17$ dex in the concentration as well when dark matterparticles are used as tracers. The dynamical state of satellite galaxies areclose to that of dark matter particles, while intracluster stars are less in asteady state, resulting in a $\sim$ 0.26 dex systematic uncertainty in mass.Compared with galactic haloes hosting Milky-Way-like galaxies, cluster haloesshow a larger stochastic bias in the recovered mass profiles. We also test theaccuracy of using intracluster gas as a dynamical tracer modelled through ageneralised hydrostatic equilibrium equation, and find a comparable systematicuncertainty in the estimated mass to that using dark matter. Lastly, wedemonstrate that our conclusions are largely applicable to other steady-statedynamical models including the spherical Jeans equation, by quantitativelysegregating their statistical efficiencies and robustness to systematics. Wealso estimate the limiting number of tracers that leads to thesystematics-dominated regime in each case.

What to expect from dynamical modelling of cluster haloes I. The information content of different dynamical tracers