The ionic composition of the local absorber towards 3C 273
  Hot ionized gas is observed in the local vicinity of our galaxy through
spectral absorption features. The most common hypothesis is that this gas forms
a halo surrounding our Milky-Way (MW), in collisional ionization equilibrium.
In this paper we investigate the elemental abundance of this hot and ionized
local gas. We use a 2.4 Ms stacked X-ray spectrum of the bright blazar 3C 273
and probe the local absorption features. Using ion-by-ion fitting of the X-ray
absorption lines we derive the column density of each ionization species. Based
on the column densities we reconstruct the Absorption measure distribution
(AMD), namely the hydrogenic column density as a function of temperature. We
report the elemental abundances of C, N, Ne, and Fe relative to solar O.
Previous measurements of local X-ray emission lines in conjunction with the
present column densities indicate a scale height of $1-80$ kpc and hydrogen
number density of $10^{-4}-10^{-3}$cm$^{-3}$ for the hot ionized gas.
Additionally, we detect He-like O lines from the quasar broad line region with
velocities of 6400$\pm$1500 km s$^{-1}$
