Related papers: The Star Formation Law in a Multifractal ISM
We have combined Halpha and recent high resolution CO(J=1-0) data to consider the quantitative relation between gas mass and star formation rate, or the so-called Schmidt law in nearby spiral galaxies at regions of high molecular density.…
Whilst the star formation rate (SFR) of molecular clouds and galaxies is key in understanding galaxy evolution, the physical processes which determine the SFR remain unclear. This uncertainty about the underlying physics has resulted in…
We use vertically-resolved numerical hydrodynamic simulations to study star formation and the interstellar medium (ISM) in galactic disks. We focus on outer disk regions where diffuse HI dominates, with gas surface densities Sigma_SFR=3-20…
The cloud-scale density, velocity dispersion, and gravitational boundedness of the interstellar medium (ISM) vary within and among galaxies. In turbulent models, these properties play key roles in the ability of gas to form stars. New high…
We study the star formation rate (SFR) versus molecular gas mass ($M_\mathrm{mol}$) scaling relation from hundreds to thousands parsec scales in two strongly lensed galaxies at redshift $z\sim 1$, the Cosmic Snake and A521. We trace SFR…
We measure the gas disc thicknesses of the edge-on galaxy NGC 4013 and the less edge-on galaxies (NGC 4157 and 5907) using CO (CARMA/OVRO) and/or HI (EVLA) observations. We also estimate the scale heights of stars and/or the star formation…
The empirical laws of star formation suggest that galactic-scale gravity is involved, but they do not identify the actual triggering mechanisms for clusters in the final stages. Many other triggering processes satisfy the empirical laws…
We study the galactic-scale triggering of star formation. We find that the largest mass-scale not stabilized by rotation, a well defined quantity in a rotating system and with clear dynamical meaning, strongly correlates with the star…
[abridged] While observations of Local Group galaxies show a very simple, local star formation law in which the star formation rate per unit area in each patch of a galaxy scales linearly with the molecular gas surface density, recent…
Observations of external galaxies and of local star-forming clouds in the Milky Way have suggested a variety of star formation laws, i.e., simple direct relations between the column density of star formation (Sigma_SFR: the amount of gas…
We investigate Schmidt's conjecture (i.e., that the star formation rate scales in a power-law fashion with the gas density) for four well-studied local molecular clouds (GMCs). Using the Bayesian methodology we show that a local Schmidt…
We investigate the nature of the star formation law at low gas surface densities using a sample of 19 low surface brightness (LSB) galaxies with existing HI maps in the literature, UV imaging from the Galaxy Evolution Explorer satellite,…
We study the relationship between the gas column density (derived from GMRT 21 cm data) and the star formation rate surface density (derived from publicly available GALEX data) for a sample of 23 extremely faint dwarf irregular galaxies…
ALMA Cycle 2 observations of the long wavelength dust emission in 180 star-forming (SF) galaxies are used to investigate the evolution of ISM masses at z = 1 to 6.4. The ISM masses exhibit strong increases from z = 0 to $\rm <z>$ = 1.15 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…
The density structure of the interstellar medium (ISM) determines where stars form and release energy, momentum, and heavy elements, driving galaxy evolution. Density variations are seeded and amplified by gas motion, but the exact nature…
We revisit the main HI-to-stellar mass ratio (gas fraction) scaling relations, taking advantage of the HI spectral stacking technique to understand the dependence of gas content on the structural and star formation properties of nearby…
We use observed radial profiles of mass surface densities of total, $\Sigma_g$, & molecular, $\Sigma_{\rm H2}$, gas, rotation velocity & star formation rate (SFR) surface density, $\Sigma_{\rm sfr}$, of the molecular-rich ($\Sigma_{\rm…
We propose an "extended Schmidt law" with explicit dependence of the star formation efficiency (SFE=SFR/Mgas) on the stellar mass surface density. This relation has a power-law index of 0.48+-0.04 and an 1-sigma observed scatter on the SFE…
We present a new particle code for modelling the evolution of galaxies. The code is based on a multi-phase description for the interstellar medium (ISM). We included star formation (SF), stellar feedback by massive stars and planetary…