Related papers: Fast Molecular Cloud Destruction Requires Fast Clo…
In this paper we investigate scaling relations between star formation rates and molecular gas masses for both local Galactic clouds and a sample of external galaxies. We specifically consider relations between the star formation rates and…
Star formation in galaxies relies on the availability of cold, dense gas, which, in turn, relies on factors internal and external to the galaxies. In order to provide a simple model for how star formation is regulated by various physical…
We summarize the current status of the turbulent model of star formation in turbulent molecular clouds. In this model, clouds, clumps and cores form a hierarchy of nested density fluctuations caused by the turbulence, and either collapse or…
Recent observations have revealed that starburst galaxies can drive molecular gas outflows through stellar radiation pressure. Molecular gas is the phase of the interstellar medium from which stars form, so these outflows curtail stellar…
We estimate the star formation efficiency per gravitational free fall time, $\epsilon_{\rm ff}$, from observations of nearby galaxies with resolution matched to the typical size of a Giant Molecular Cloud. This quantity, $\epsilon_{\rm…
Giant molecular clouds (GMCs) are the primary reservoirs of cold, star-forming molecular gas in the Milky Way and similar galaxies, and thus any understanding of star formation must encompass a model for GMC formation, evolution, and…
Star formation depends on the available gaseous "fuel" as well as galactic environment, with higher specific star formation rates where gas is predominantly molecular and where stellar (and dark matter) densities are higher. The partition…
Young galaxies are clumpy, gas-rich, and highly turbulent. Star formation appears to occur by gravitational instabilities in galactic disks. The high dispersion makes the clumps massive and the disks thick. The star formation rate should be…
Newborn stars form within the localized, high density regions of molecular clouds. The sequence and rate at which stars form in dense clumps and the dependence on local and global environments are key factors in developing descriptions of…
Several active galaxies show strong evidence for fast ($v_{\rm out} \sim 1000~{\rm km\,s}^{-1}$) massive ($\dot{M} =$ several $\times 1000~\msun\,{\rm yr}^{-1}$) gas outflows. Such outflows are expected on theoretical grounds once the…
We study gravitational collapse of low-metallicity gas clouds and the formation of protostars by three-dimensional hydrodynamic simulations. Grain growth, non-equilibrium chemistry, molecular cooling, and chemical heating are solved in a…
We carry out three-dimensional MHD simulations of star formation in turbulent, magnetized clouds, including ambipolar diffusion and feedback from protostellar outflows. The calculations focus on relatively diffuse clouds threaded by a…
Observations indicate that massive stars form in regions of very high surface density, ~1 g cm^-2. Clusters containing massive stars and globular clusters have a comparable column density. The total pressure in clouds of such a column…
Stars form by gravoturbulent fragmentation of interstellar gas clouds. The supersonic turbulence ubiquitously observed in Galactic molecular gas generates strong density fluctuations with gravity taking over in the densest and most massive…
We present a new model to describe the star formation process in galaxies, which includes the description of the different gas phases -- molecular, atomic, and ionized -- together with its metal content. The model, which will be coupled to…
The physical conditions in molecular clouds control the nature and rate of star formation, with consequences for planet formation and galaxy evolution. The focus of this review is on the conditions that characterize regions of star…
Galaxy growth depends critically on the interplay between radiative cooling of cosmic gas and the resulting energetic feedback that cooling triggers. This interplay has proven exceedingly difficult to model, even with large supercomputer…
We explore, through a simplified, semi-analytic model, the formation of dense clusters containing massive stars. The parent cloud spawning the cluster is represented as an isothermal sphere. This sphere is in near force balance between…
Our current understanding of the physical processes of star formation is reviewed, with emphasis on processes occurring in molecular clouds like those observed nearby. The dense cores of these clouds are predicted to undergo gravitational…
We compare the structure of molecular gas at $40$ pc resolution to the ability of gas to form stars across the disk of the spiral galaxy M51. We break the PAWS survey into $370$ pc and $1.1$ kpc resolution elements, and within each we…