相关论文: Midplane Gas Density and the Schmidt Law
We aim to understand the physical mechanisms that drive star formation in a sample of mass-complete (>10$^{9.5}M_{\odot}$) star-forming galaxies (SFGs) at 1.2 $\leq z$ < 1.6. We selected SFGs from the COSMOS2020 catalog and applied a…
We investigate the dependence of the local space density of spiral galaxies on luminosity, scalesize and surface brightness. We derive bivariate space density distributions in these quantities from a sample of about 1000 Sb-Sdm spiral…
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…
The interstellar medium (ISM) reveals strongly inhomogeneous structures at every scale. These structures do not seem completely random since they obey certain power laws. Larson's law (\citeyear{Larson81}) $\sigma \propto R^{\delta}$ and…
Given the dimensions (including thickness) of an axisymmetric galaxy, Newton's law is used in integral form to find the density distributions required to match a wide range of orbital speed profiles. Newton's law is not modified and no dark…
A very simple physical model of galaxies, in which the formation of stars is instantaneously regulated by the mass of gas in a reservoir, links together three different aspects of the evolving galaxy population:(a) the cosmic time evolution…
High--resolution 2D--MHD numerical simulations have been carried out to investigate the effects of continuing infall of clumpy gas in extended HI galactic disks. Given a certain accretion rate, the response of the disk depends on its…
Despite many studies of the star formation in spiral galaxies, a complete and coherent understanding of the physical processes that regulate the birth of stars has not yet been achieved, nor a unanimous consent was reached, despite the many…
Observations reveal that mature spiral galaxies consist of stars, gases and plasma approximately distributed in a thin disk of circular shape, usually with a central bulge. The rotation velocities quickly increase from the galactic center…
Empirical star formation laws from the last 20 years are reviewed with a comparison to simulations. The current form in main galaxy disks has a linear relationship between the star formation rate per unit area and the molecular cloud mass…
Using the HST archive WFPC2 observations and rotation curves measeured by Vogt et al. (1996), we constructed self-consistent light and mass distribution models for three disk galaxies at redshifts z = 0.15, 0.90 and 0.99. The models consist…
Given the dimensions(including thickness) of an axisymmetric galaxy, Newton's law is used in integral form to find the density distributions required to match a wide range of orbital speed profiles. Newton's law is not modified and no…
We investigate in detail the hypothesis that low surface brightness galaxies (LSB) differ from ordinary galaxies simply because they form in halos with large spin parameters. We compute star formation rates using the Schmidt law, assuming…
The global Schmidt law of star formation provides a power-law relation between the surface densities of star-formation rate (SFR) and gas, and successfully explains plausible scenarios of galaxy formation and evolution. However, star…
The Halpha and mid-infrared mean disk surface brightnesses are compared in a sample of nearby spirals observed by ISOCAM. This shows that, in spiral disks, dust emission at 7 and 15 microns provides a reasonable star formation tracer. The…
On the basis of a large scale 'adiabatic', namely non-radiative and non-dissipative, cosmological smooth particle hydrodynamic simulation we compare the entropy profiles of the gas and the dark matter (DM) in galaxy clusters. The quantity…
We use spectra from the ALFALFA, GASS and COLD GASS surveys to quantify variations in the mean atomic and molecular gas mass fractions throughout the SFR-M* plane and along the main sequence (MS) of star-forming galaxies. Although galaxies…
I model the multi-phase interstellar medium (ISM) randomly heated and shocked by supernovae, with gravity, differential rotation and other parameters we understand to be typical of the solar neighbourhood. The simulations are 3D extending…
Simulations indicate that the inflow of gas of star-forming galaxies is almost co-planar and co-rotating with the gas disk, and that the outflow of gas driven by stellar winds and/or supernova explosions is preferentially perpendicular to…
Stars do not form continuously distributed over star forming galaxies. They form in star clusters of different masses. This nature of clustered star formation is taken into account in the theory of the integrated galactic stellar initial…