{ "id": "2010.16195", "version": "v1", "published": "2020-10-30T11:15:45.000Z", "updated": "2020-10-30T11:15:45.000Z", "title": "The stellar mass function and evolution of the density profile of galaxy clusters from the Hydrangea simulations at $010^{14} \\textrm{M}_{\\odot}$) at different redshifts ($010^{14} \\textrm{M}_{\\odot}$ at $z=0$). We compare three fundamental observables of galaxy clusters: the total stellar mass to halo mass ratio, the stellar mass function (SMF), and the radial mass density profile of the cluster galaxies. In the first two of these, the simulations agree well with the observations, albeit with a slightly too high abundance of $M_\\star \\lesssim 10^{10} \\textrm{M}_{\\odot}$ galaxies at $z \\gtrsim 1$. The NFW concentrations of cluster galaxies increase with redshift, in contrast to the decreasing dark matter halo concentrations. This previously observed behaviour is therefore due to a qualitatively different assembly of the smooth DM halo compared to the satellite population. Quantitatively, we however find a discrepancy in that the simulations predict higher stellar concentrations than observed at lower redshifts ($z<0.3$), by a factor of $\\approx$2. This may be due to selection bias in the simulations, or stem from shortcomings in the build-up and stripping of their inner satellite halo.", "revisions": [ { "version": "v1", "updated": "2020-10-30T11:15:45.000Z" } ], "analyses": { "keywords": [ "stellar mass function", "density profile", "dark matter halo concentrations", "hydrangea simulations", "simulations predict higher stellar concentrations" ], "note": { "typesetting": "TeX", "pages": 14, "language": "en", "license": "arXiv", "status": "editable" } } }