相关论文: Collapse of turbulent massive cores with ambipolar…
We investigate the properties of highly compressible turbulence, the compressibility arising from a small effective polytropic exponent $\gamma_e$ due to cooling. In the limit of small $\gamma_e$, the density jump at shocks is shown to be…
A fundamental challenge in star formation is understanding how a protostar accretes mass from its circumstellar disk while removing excess angular momentum. Protostellar jets are widely invoked as the primary channels for angular momentum…
Observational advances over the last decade reveal that star formation is associated with the simultaneous presence of gravitationally collapsing gas, bipolar outflow, and an accretion disk. Two theoretical views of star formation suppose…
High rates of stable mass transfer likely occur for some binary star systems, but the resulting flow of mass and angular momentum (AM) is unclear. We perform hydrodynamical simulations of a polytropic donor star and a point mass secondary…
We report the detection of large variations in the outflow wind velocity from a young eruptive star, V899 Mon during its ongoing high accretion outburst phase. Such large variations in the outflow velocity (from -722 km s$^{-1}$ to -425 km…
Massive protostars generate strong radiation feedback, which may help set the mass they achieve by the end of the accretion process. Studying such feedback is therefore crucial for understanding the formation of massive stars. We report the…
Star formation is intimately linked to the dynamical evolution of molecular clouds. Turbulent fragmentation determines where and when protostellar cores form, and how they contract and grow in mass via accretion from the surrounding cloud…
The giant, star forming clumps in gas-rich, high redshift disks are commonly assumed to form due to gravitational instabilities, in which protoclumps have a Toomre-$Q$ parameter less than unity. However, some cosmological simulations show…
We study, by numerical simulations, the entrainment process in a supersonic, radiative jet flow, during the evolution of Kelvin-Helmholtz instabilities, in the context of the the acceleration problem of molecular bipolar outflows, observed…
Short abstract: We present fully 3-D simulations of supersonic, radiatively cooling intermittent jets with intermediate and long variability periods (that is, periods of the order of or longer than, the dynamical time scale of the jet).…
Large-scale magnetic field is crucial in launching and collimating the jets/outflows. It is found that the magnetic flux can be efficiently transported inward by the fast moving corona above a thin disk. In this work we investigate the…
Magnetically mediated disk outflows are a leading paradigm to explain winds and jets in a variety of astrophysical sources, but where do the fields come from? Since accretion of mean magnetic flux may be disfavored in a thin turbulent disk,…
We consider formation of accretion disks from a realistically turbulent molecular gas using 3D MHD simulations. In particular, we analyze the effect of the fast turbulent reconnection described by the Lazarian & Vishniac (1999) model for…
We presents results from Smoothed Particle Magnetohydrodynamics simulations of collapsing molecular cloud cores, and dynamo amplification of the magnetic field in the presence of Mach 10 magnetised turbulence. Our star formation simulations…
The BN/KL region in the Orion molecular cloud is an archetype in the study of the formation of stars much more massive than the Sun. This region contains luminous young stars and protostars, but it is difficult to study because of overlying…
Magnetic fields play a fundamental role in the formation of protostellar winds. In the magneto-centrifugal models, poloidal magnetic fields launch winds from accretion disks, and fast-rotating gas twists the fields into toroidal geometry…
We discuss recent progress in understanding the launching of outflows/jets from the disc-magnetosphere boundary of slowly and rapidly rotating magnetized stars. In most of the discussed models the interior of the disc is assumed to have a…
Disks are essential to the formation of both stars and planets, but how they form in magnetized molecular cloud cores remains debated. This work focuses on how the disk formation is affected by turbulence and ambipolar diffusion (AD), both…
The observed rapid onset of star formation in molecular clouds requires rapid formation of dense fragments which can collapse individually before being overtaken by global gravitationally-driven flows. Many previous investigations have…
The driving mechanism of protostellar outflows and jets and their effects on the star formation process obtained from recent theoretical and numerical studies are described. Low-velocity outflows are driven by an outer region of the…