相关论文: A ram-pressure threshold for star formation

Cosmic rays (CRs) control the thermal, ionization and chemical state of the dense H_2 gas regions that otherwise remain shielded from far-UV and optical stellar radiation propagating through the dusty ISM of galaxies. It is in such…

We present results of a semi-analytic model (SAM) that includes cold accretion and a porosity-based prescription for star formation. We can recover the puzzling observational results of low $V/\sigma$ seen in various massive disk or…

We report results from a cosmological simulation with non-equilibrium chemistry of 21 species, including H2, HD, and LiH molecular cooling. Starting from cosmological initial conditions, we focus on the evolution of the central 1.8 Kpc…

We present first results of a study aimed to constrain the star formation rate and dust content of galaxies at z~2. We use a sample of BzK-selected star-forming galaxies, drawn from the COSMOS survey, to perform a stacking analysis of their…

We study the gravitational fragmentation of cold accretion streams flowing into a typical first galaxy. We use a one-zone hydrodynamical model to examine the thermal evolution of the gas entering a 10^8 M_sun DM halo at z=10. The goal is to…

In order to constrain the initial mass function (IMF) of the first generation of stars (Population III), we investigate the fragmentation properties of metal-free gas in the context of a hierarchical model of structure formation. We…

The accretion phase of star formation is investigated in magnetically-dominated clouds that have an initial subcritical mass-to-flux ratio. We employ nonideal magnetohydrodynamic simulations that include ambipolar diffusion and ohmic…

Massive stars form in clusters within self-gravitating molecular clouds. The size scale of these clusters is sufficiently large that non-thermal, or turbulent, motions of the gas must be taken into account when considering their formation.…

Fragmentation of protostellar disks controls the growth of protostars and plays a key role in determining the final mass of newborn stars. In this paper, we investigate the structure and gravitational stability of the protostellar disks in…

We examine whether massive-star accretion disks are likely to fragment due to self-gravity. Rapid accretion and high angular momentum push these disks toward fragmentation, whereas viscous heating and the high protostellar luminosity…

We use cosmological hydrodynamic simulations with unprecedented resolution to study the formation of primordial stars in an ionized gas at high redshifts. Our approach includes all the relevant atomic and molecular physics to follow the…

Sheet-like clouds are common in turbulent gas and perhaps form via collisions between turbulent gas flows. Having examined the evolution of an isothermal shocked slab in an earlier contribution, in this work we follow the evolution of a…

We investigate the impact of star formation and feedback on ram pressure stripping using high-resolution adaptive mesh simulations, building on a previous series of papers that systematically investigated stripping using a realistic model…

Gas can be violently stripped from their galaxy disks in rich clusters, and be dispersed over 100kpc-scale tails or plumes. Young stars have been observed in these tails, suggesting they are formed in situ. This will contribute to the…

Using a version of the ZEUS code, we carry out two-dimensional simulations of self-gravitating shearing sheets, with application to QSO accretion disks at a few thousand Schwarzschild radii, corresponding to a few hundredths of a parsec for…

Nuclear rings in barred galaxies are sites of active star formation. We use hydrodynamic simulations to study temporal and spatial behavior of star formation occurring in nuclear rings of barred galaxies where radial gas inflows are…

We study the formation of the first generation of stars in the standard cold dark matter model, using a very high-resolution hydordynamic simulations. Our simulation achieves a dynamic range of 10^{10} in length scale. With accurate…

A fundamental physical basis is provided for the recently obtained minimum column density (1gcm-2) for massive star formation.

With the help of a statistical parameter derived from optical spectra, we show that the current star formation rate of a galaxy, falling into a cluster along a supercluster filament, is likely to undergo a sudden enhancement before the…

Massive stars influence their surroundings through radiation, winds, and supernova explosions far out of proportion to their small numbers. However, the physical processes that initiate and govern the birth of massive stars remain poorly…