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Our goal is to provide a robust estimate of the metal content of the ICM in massive clusters. We make use of published abundance profiles for a sample of ~60 nearby systems, we include in our estimate uncertainties associated to the measurement process and to the almost total lack of measures in cluster outskirts. We perform a first, albeit rough, census of metals finding that the mean abundance of the ICM within r_180 is very poorly constrained, 0.06Z_sol < Z < 0.26Z_sol, and presents no tension with expectations. Similarly, the question of if and how the bulk of the metal content in clusters varies with cosmic time, is very much an open one. A solid estimate of abundances in cluster outskirts could be achieved by combining observations of the two experiments which will operate on board Athena, the XIFU and the WFI, provided they do not fall victim to the de-scoping process that has afflicted several space observatories over the last decade.
In this paper we perform a comprehensive study of the main sources of random and systematic errors in stellar mass measurement for galaxies using their Spectral Energy Distributions (SEDs). We use mock galaxy catalogs with simulated multi-waveband ph
We use the halo occupation distribution (HOD) framework to characterise the predictions from two independent galaxy formation models for the galactic content of dark matter haloes and its evolution with redshift. Our galaxy samples correspond to a ra
We consider spherically symmetric inhomogeneous pressure Stephani universes, the center of symmetry being our location. The main feature of these models is that comoving observers do not follow geodesics. In particular, comoving perfect fluids have n
Measurements of the neutral hydrogen gas content of a sample of 93 post-merger galaxies are presented, from a combination of matches to the ALFALFA.40 data release and new Arecibo observations. By imposing completeness thresholds identical to that of
We use the Hubble Space Telescope (HST) archive of ultraviolet (UV) quasar spectroscopy to conduct the first blind survey for damped Ly-alpha absorbers (DLAs) at low redshift (z < 1.6). Our statistical sample includes 463 quasars with spectral covera