Properties of the circumgalactic medium in simulations compared to
  observations
  Galaxies are surrounded by extended gaseous halos which store significant
fractions of chemical elements. These are syntethized by the stellar
populations and later ejected into the circumgalactic medium (CGM) by different
mechanism, of which supernova feedback is considered one of the most relevant.
We explore the properties of this metal reservoir surrounding star-forming
galaxies in a cosmological context aiming to investigate the chemical loop
between galaxies and their CGM, and the ability of the subgrid models to
reproduce observational results. Using cosmological hydrodynamical simulations,
we analyse the gas-phase chemical contents of galaxies with stellar masses in
the range $10^{9} - 10^{11}\,{\rm M}_{\odot}$. We estimate the fractions of
metals stored in the different CGM phases, and the predicted OVI and SiIII
column densities within the virial radius. We find roughly $10^{7}\,{\rm
M}_{\odot}$ of oxygen in the CGM of simulated galaxies having
$M_{\star}{\sim}10^{10}\,{\rm M}_{\odot}$, in fair agreement with the lower
limits imposed by observations. The $M_{\rm oxy}$ is found to correlate with
$M_{\star}$, at odds with current observational trends but in agreement with
other numerical results. The estimated profiles of OVI column density reveal a
substantial shortage of that ion, whereas SiIII, which probes the cool phase,
is overpredicted. The analysis of the relative contributions of both ions from
the hot, warm and cool phases suggests that the warm gas ($ 10^5~{\rm K} < T <
10^6~{\rm K}$) should be more abundant in order to bridge the mismatch with the
observations, or alternatively, that more metals should be stored in this
gas-phase. Adittionally, we find that the X-ray coronae around the simulated
galaxies have luminosities and temperatures in decent agreement with the
available observational estimates. [abridged]
