Related papers: The Interaction of the Disk with the Halo
The formation of galactic discs and the efficiency of star formation within them are issues central to our understanding of galaxy formation. We have developed a detailed and versatile model of disc formation which combines the strengths of…
Thick layers of warm, low density ionized hydrogen (i.e., the warm ionized medium or WIM) in spiral galaxies provide direct evidence for an interaction between the disk and halo. The wide-spread ionization implies that a significant…
The results of a three-dimensional model for disk-halo interaction are presented here. The model considers explicitly the input of energy and mass by isolated a nd correlated supernovae in the disk. Once disrupted by the explosions, the…
Galactic halo gas traces inflowing star formation fuel and feedback from a galaxy's disk and is therefore crucial to our understanding of galaxy evolution. In this review, we summarize the multi-wavelength observational properties and…
Supermassive primordial stars with masses exceeding $\sim10^5\,M_{\odot}$ that form in atomically cooled halos are the leading candidates for the origin of high-redshift quasars with $z>6$. Recent numerical simulations, however, find that…
Galaxies are surrounded by large halos of hot gas which must be replenished as the gas cools. This led Norman & Ikeuchi (1989) to propose the chimney model of the interstellar medium, which predicts that there should be on the order of a…
Galaxy disks are characterised by star formation histories that vary systematically along the Hubble sequence. We study global star formation, incorporating supernova feedback, gas accretion and enriched outflows in disks modelled by a…
Some aspects of disk-halo interactions for models of in and out of equilibrium disk galaxies are reviewed. Specifically, we focus on disk-halo resonant interaction without and in the presence of a gas component. Another issue is the disk…
The normal mode theory for warping of galaxy disks, in which disks are assumed to be tilted with respect to the equator of a massive, flattened dark halo, assumes a rigid, fixed halo. However, consideration of the back-reaction by a…
Deep photometric surveys of the Milky Way have revealed diffuse structures encircling our Galaxy far beyond the "classical" limits of the stellar disk. This paper reviews results from our own and other observational programs, which together…
Halo clouds have been found about the three largest galaxies of the Local Group and in the halos of nearby spirals. This suggests they are a relatively generic feature of the galaxy evolution process and a source of fuel for galaxy disks.…
Correlations between stellar kinematics and chemical abundances are fossil evidence for evolutionary connections between Galactic structural components. Extensive stellar surveys show that the only tolerably clear distinction between…
The development of our understanding of the gaseous component of the interstellar medium is reviewed. During the 20th century our picture of diffuse material in space has grown from a simple model of isolated clouds in thermal equilibrium…
Disk galaxies evolve over time through processes that may rearrange both the radial mass profile and the metallicity distribution within the disk. This review of such slow changes is largely, though not entirely, restricted to…
This paper explores the dynamical interaction between extended halo and spheroid components of a disk galaxy and an environmental disturbance. One finds that resonant interaction between a galaxy and passing interlopers or satellite…
We investigate how the empirical properties of hot X-ray-emitting gas in a sample of seven starburst and three normal edge-on spiral galaxies (a sample which covers the full range of star-formation intensity found in disk galaxies)…
We have performed hydrodynamic simulations of galaxy formation in a LCDM universe. We have followed galaxy formation in a dark matter halo, chosen to have a relatively quiet recent merger history, using different models for star formation…
Observations of turbulent velocity dispersions in the HI component of galactic disks show a characteristic floor in galaxies with low star formation rates and within individual galaxies the dispersion profiles decline with radius. We carry…
Recent observations have discovered star formation activities in the extreme outer regions of disk galaxies. However it remains unclear what physical mechanisms are responsible for triggering star formation in such low-density gaseous…
We study the ionizing sources in spiral galaxies and examine in more detail our Galaxy. Using Taylor & Cordes (1993) model we analyze the electron density in different parts of the Galaxy, and emphasize the still unsolved problems. Finally,…