Related papers: The origin of the high-velocity cloud complex C
In recent years surveys have identified several dozen B stars in the Milky Way halo moving faster than the local escape speed. The origin of most of these hypervelocity stars (HVSs) is still poorly constrained. Here we show that the…
The diffuse gamma-ray sky revealed 'Bubbles' of emission above and below the Galactic Plane symmetric around the centre of the Milky Way with a height of 10 kpc in both directions. At present there is no convincing explanation for the…
The Galactic bulge, that is the prominent out-of-plane over-density present in the inner few kiloparsecs of the Galaxy, is a complex structure, as the morphology, kinematics, chemistry and ages of its stars indicate. To understand the…
The evolution of molecular clouds in galactic centres is thought to differ from that in galactic discs due to a significant influence of the external gravitational potential. We present a set of numerical simulations of molecular clouds…
The interstellar medium within $\rm\approx 15 \; pc$ of the Sun consists of a complex of fifteen diffuse, partially ionized clouds. Located within the Local Bubble, these clouds, known as the Cluster of Local Interstellar Clouds (CLIC),…
The origin of the molecular clouds orbiting SgrA* is one of the most debated questions about our Galactic Centre. Here, we present the hydrodynamic simulation of a molecular cloud infalling towards SgrA*, performed with the…
Molecular clouds (MCs) are highly structured and ``turbulent''. Colliding gas streams of atomic hydrogen have been suggested as a possible source of MCs, imprinting the filamentary structure as a consequence of dynamical and thermal…
The high-velocity, neutral hydrogen feature known as MI may be the result of a supernova that took place about 100,000 years ago at a distance of 163 pc. Low-velocity HI data show a clear cavity, a structure indicative of regions evacuated…
With the goal of understanding why X-rays have been reported near some high velocity clouds, we perform detailed 3 dimensional hydrodynamic and magnetohydrodynamic simulations of clouds interacting with environmental gas like that in the…
In the standard paradigm of galaxy formation and evolution, the baryonic component of galaxies forms from the collapse and condensation of gas within dark matter haloes, and later grows from continuous accretion of gaseous mass, both in…
We propose a new mechanism for the delivery of gas to the heart of galactic nuclei. We show that warm halo clouds must periodically impact galactic centers and potentially deliver a large (~10^{4-6} M_{solar}) mass of gas to the galactic…
The high- and intermediate-velocity interstellar clouds (HVCs/IVCs) are tracers of energetic processes in and around the Milky Way. Clouds with near-solar metallicity about one kpc above the disk trace the circulation of material between…
We analyze an adaptive mesh refinement hydrodynamic cosmological simulation of a Milky Way-sized galaxy to study the cold gas in the halo. HI observations of the Milky Way and other nearby spirals have revealed the presence of such gas in…
High-mass stars are commonly found in stellar clusters promoting the idea that their formation occurs due to the physical processes linked with a young stellar cluster. It has recently been reported that isolated high-mass stars are present…
The study of the Milky Way stellar discs in the context of galaxy formation is discussed. In particular we explore the properties of the Milky Way disc using a new sample of about 550 dwarf stars for which we have recently obtained…
A recent discovery of two stellar clusters associated with the diffuse high-latitude cloud HRK 81.4-77.8 has important implications for star formation in the Galactic halo. We derive a plausible distance estimate to HRK 81.4-77.8 primarily…
On both observational and theoretical grounds, the disk of our Galaxy should be accreting cool gas with temperature ~<10^5 K via the halo at a rate ~1 M_sun/yr. At least some of this accretion is mediated by high velocity clouds (HVCs),…
The origin of the dense gas cloud G2 discovered in the Galactic Center (Gillessen et al. 2012) is still a debated puzzle. G2 might be a diffuse cloud or the result of an outflow from an invisible star embedded in it. We present here…
We provide new insight on the origin of the cold high-V$_{\rm los}$ peaks ($\sim$200 kms$^{-1}$) in the Milky Way bulge discovered in the APOGEE commissioning data \citep{Nidever2012}. Here we show that such kinematic behaviour present in…
Using a set of 15 high-resolution magnetohydrodynamic cosmological simulations of Milky Way formation, we investigate the origin of the baryonic material found in stars at redshift zero. We find that roughly half of this material originates…