Constraining density and metallicity of the Milky Way's hot gas halo
  from O VII spectra and ram-pressure stripping
  Milky Way's hot gaseous halo extends up to the Galactic virial radius ($\sim
200$ kpc) and contains a significant component of baryon mass of the Galaxy.
The halo properties can be constrained from X-ray spectroscopic observations
and from satellite galaxies' ram-pressure stripping studies. Results of the
former method crucially depend on the gas metallicity assumptions while the
latter one's are insensitive to them. Here, a joint analysis of both kinds of
data is presented to constrain electron density and metallicity of the gas. The
power law is assumed for the electron density radial profile, while for the
metallicity, a common-used constant-metallicity assumption is relaxed by
introducing of a physically motivated spherical profile. The model is fitted to
a sample of 431 (18) sight lines for O VII emission (absorption) measurements
and 7 electron density constraints from ram-pressure stripping studies. The
best-fitting halo-associated electron density profile of $n_e\propto
r^{-(0.9...1.1)}$ (where $r\gg1$ kpc is the galactocentric radius) is found.
The metallicity is constrained as $Z \approx (0.1...0.7) Z_{\odot}$ (subscript
$\odot$ represents the solar values) at $r>50$ kpc. These imply a total hot gas
mass of $M \approx (2.4...8.7) \times 10^{10} M_{\odot}$, which accounts for
$\sim(17...100)$ per cent of the Milky Way's missing baryon mass. The model
uncertainties are discussed, and the results are examined in the context of
previous studies.
