Related papers: Mass, Morphing, Metallicities: The Evolution of In…
Measurements of high-velocity clouds' metallicities provide important clues about their origins, and hence on whether they play a role in fueling ongoing star formation in the Galaxy. However, accurate interpretation of these measurements…
The formation of molecular clouds out of HI gas is the first step toward star formation. Its metallicity dependence plays a key role to determine star formation through the cosmic history. Previous theoretical studies with detailed chemical…
In the Galactic halo, metal-bearing Galactic halo material mixes into high velocity clouds (HVCs) as they hydrodynamically interact. This interaction begins long before the clouds completely dissipate and long before they slow to the…
Atmospheres regulate the planetary heat loss and therefore influence planetary thermal evolution. Uncertainty in a giant planet's thermal state contributes to the uncertainty in the inferred abundance of heavy elements it contains. Within…
In the Galactic fountain scenario, supernovae and/or stellar winds propel material into the Galactic halo. As the material cools, it condenses into clouds. By using FLASH three-dimensional magnetohydrodynamic simulations, we model and study…
A model is proposed for determining the distances to falling interstellar clouds in the galactic halo by measuring the cloud velocity and column density and assuming a model for the vertical density distribution of the Galactic interstellar…
Using adaptive mesh refinement (AMR) hydrodynamic simulations of vertically stratified hot halo gas, we examine the conditions under which clouds can form and condense out of the hot halo medium to potentially fuel star formation in the…
The thermal and chemical evolution of gravitationally collapsing protostellar clouds is investigated, focusing attention on their dependence on metallicity. Calculations are carried out for a range of metallicities spanning the local…
The molecular component of the Galaxy is comprised of turbulent, magnetized clouds, many of which are self-gravitating and form stars. To understand how these clouds' evolution may depend on their level of turbulence, mean magnetization,…
The Smith Cloud is a gaseous high-velocity cloud (HVC) in an advanced state of accretion, only 2.9 kpc below the Galactic plane and due to impact the disk in 27 Myr. It is unique among HVCs in having a known distance (12.4+/-1.3 kpc) and a…
We present hydrodynamic simulations of high-velocity clouds (HVCs) traveling through the hot, tenuous medium in the Galactic halo. A suite of models was created using the FLASH hydrodynamics code, sampling various cloud sizes, densities,…
HI observations of high-velocity clouds (HVCs) indicate, that they are interacting with their ambient medium. Even clouds located in the very outer Galactic halo or the intergalactic space seem to interact with their ambient medium. In this…
We present a study of the ionization and thermal structure of neutral hydrogen clouds located in the Galactic halo, immersed in the extragalactic background radiation field, and supposed to be in pressure equilibrium with the surrounding…
The high-velocity cloud (HVC) Complex A is a probe of the physical conditions in the Galactic halo. The kinematics, morphology, distance, and metallicity of Complex A indicate that it represents new material that is accreting onto the…
There is a fortuitous coincidence in the positions of the quasar TonS210 and the compact H I high velocity cloud CHVC224.0-83.4-197 on the sky. Using Far Ultraviolet Spectroscopic Explorer observations of the metal-line absorption in this…
The Galaxy is in continuous elemental evolution. Since new elements produced by dying stars are delivered to the interstellar medium, the formation of new enerations of stars and planetary systems is influenced by this metal enrichment. We…
We perform linear analysis of thermal instability in a contracting large cloud filled with warm HI gas and investigate the effect of metallicity and radiation flux. When the cloud reaches critical density n_f, the cloud fragments into cool,…
We numerically investigate the evolution of compact high-velocity clouds (CHVCs) passing through a hot, tenuous gas representing the highly-ionized circumgalactic medium (CGM) by applying the adaptive-mesh refinement code FLASH. The model…
Throughout the passage within the Galactic halo, high-velocity clouds (HVCs) sweep up ambient magnetic fields and form stretched and draped configurations of magnetic fields around them. Many earlier numerical studies adopt spherically…
High velocity gas that does not conform to Galactic rotation is observed throughout the Galaxy's halo. One component of this gas, HI high velocity clouds (HVCs), have attracted attention since their discovery in the 1960s and remain…