Аннотация
We study the evolution of the stellar component and the metallicity of both
the intracluster medium and of stars in massive ($M_vir6\times
10^14$ M$_ødot$) simulated galaxy clusters from the RHAPSODY-G suite in
detail and compare them to observational results. The simulations were
performed with the AMR code RAMSES and include the effect of AGN feedback at
the sub-grid level. AGN feedback is required to produce realistic galaxy and
cluster properties and plays a role in mixing material in the central regions
and regulating star formation in the central galaxy. In our low resolution runs
with fiducial stellar yields, we find that stellar and ICM metallicities are a
factor of two lower than in observations, however they tend to converge to the
observed values $0.3$ Z$_ødot$ as the resolution is increased. We find
that cool core clusters exhibit steeper metallicity gradients than non-cool
core clusters, in qualitative agreement with observations. We verify that the
ICM metallicities measured in the simulation can be explained by a simple
"regulator" model in which the metallicity is set by a balance of stellar yield
and gas accretion. The analytical model also predicts that the metallicities
are proportional to the stellar yield. Our results thus indicate that a
combination of higher resolution and higher metal yield in AMR simulation would
allow the metallicity of simulated clusters to match observed values.
Comparison to recent literature highlights that results concerning the
metallicity of clusters and cluster galaxies might depend severely on the
scheme chosen to solve the hydrodynamics.
Пользователи данного ресурса
Пожалуйста,
войдите в систему, чтобы принять участие в дискуссии (добавить собственные рецензию, или комментарий)