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Theoretical and observational arguments suggest that there is a large amount of hot ($sim 10^6$ K), diffuse gas residing in the Milky Ways halo, while its total mass and spatial distribution are still unclear. In this work, we present a general model for the gas density distribution in the Galactic halo, and investigate the gas evolution under radiative cooling with a series of 2D hydrodynamic simulations. We find that the mass inflow rate in the developed cooling flow increases with gas metallicity and the total gas mass in the halo. For a fixed halo gas mass, the spatial gas distribution affects the onset time of the cooling catastrophe, which starts earlier when the gas distribution is more centrally-peaked, but does not substantially affect the final mass inflow rate. The gravity from the Galactic bulge and disk affects gas properties in inner regions, but has little effect on the final inflow rate either. We confirm our results by investigating cooling flows in several density models adopted from the literature, including the Navarro-Frenk-White (NFW) model, the cored-NFW model, the Maller & Bullock model, and the $beta$ model. Typical mass inflow rates in our simulations range from $sim 5 M_{odot}$ yr$^{-1}$ to $sim 60 M_{odot}$ yr$^{-1}$, and are much higher than the observed star formation rate in our Galaxy, suggesting that stellar and active galactic nucleus feedback processes may play important roles in the evolution of the Milky Way (MW) and MW-type galaxies.
We propose a novel method to constrain the Milky Way (MW) mass $M_{rm vir}$ with its corona temperature observations. For a given corona density profile, one can derive its temperature distribution assuming a generalized equilibrium model with non-th
The circumgalactic region of the Milky Way contains a large amount of gaseous mass in the warm-hot phase. The presence of this warm-hot halo observed through $z=0$ X-ray absorption lines is generally agreed upon, but its density, path-length, and mas
In 1998 several papers claim the detection of an ubiquitous gaseous phase within the Galactic halo. Here we like to focus on the detections of X-ray emitting gas within the Galactic halo as well as the discovery of a pervasive neutral Galactic halo g
We present the study of a set of N-body+SPH simulations of a Milky Way-like system produced by the radiative cooling of hot gas embedded in a dark matter halo. The galaxy and its gaseous halo evolve for 10 Gyr in isolation, which allows us to study h
The halo of the Milky Way provides a laboratory to study the properties of the shocked hot gas that is predicted by models of galaxy formation. There is observational evidence of energy injection into the halo from past activity in the nucleus of the