Abstract
Single-phase photoionization equilibrium (PIE) models are often used to infer
the underlying physical properties of galaxy halos probed in absorption with
ions at different ionization potentials. To incorporate the effects of
turbulence, we use the MAIHEM code to model an isotropic turbulent medium
exposed to a redshift zero metagalactic UV background, while tracking the
ionizations, recombinations, and species-by-species radiative cooling for a
wide range of ions. By comparing observations and simulations over a wide range
of turbulent velocities, densities, and metallicity with a Markov chain Monte
Carlo technique, we find that MAIHEM models provide an equally good fit to the
observed low-ionization species compared to PIE models, while reproducing at
the same time high-ionization species such as Si4 and O6. By
including multiple phases, MAIHEM models favor a higher metallicity ($Z/Z_ødot
40\%$) for the circumgalactic medium compared to PIE models.
Furthermore, all of the solutions require some amount of turbulence
($\sigma_3D 26\ km\ s^-1$). Correlations between
turbulence, metallicity, column density, and impact parameter are discussed
alongside mechanisms that drive turbulence within the halo.
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