相关论文: Spiral arm triggering of star formation
We use the high spatial and spectral resolution of the PAWS CO(1-0) survey of the inner 9 kpc of the iconic spiral galaxy M51 to examine the effect of gas streaming motions on the star-forming properties of individual GMCs. We compare our…
A cloud of gas collapsing under gravity will fragment. We present a new theory for this process, in which layers shocked gas fragment due to their gravitational instability. Our model explains why angular momentum does not inhibit the…
We model gravitational collapse leading to star formation in a wide range of isolated disk galaxies using a three-dimensional, smoothed particle hydrodynamics code. The model galaxies include a dark matter halo and a disk of stars and…
The formation of the massive young stars surrounding SgrA* is still an open question. In this paper, we simulate the infall of an isothermal, turbulent molecular cloud towards the Galactic Centre (GC). As it spirals towards the GC, the…
We review the properties of turbulent molecular clouds (MCs), focusing on the physical processes that influence star formation (SF). MC formation appears to occur during large-scale compression of the diffuse ISM driven by supernovae,…
The formation and evolution of giant molecular clouds (GMCs) in spiral galaxies have been investigated in the traditional framework of the combined quasi-stationary density wave and galactic shock model. However, our understanding of the…
We study the effects of passages of compact objects such as stars, star clusters, and black holes through molecular clouds, and propose that the gravitational interaction between the compact object and the ambient gas can lead to the…
We present preliminary numerical evidence that the physical conditions in high-mass star forming regions can arise from global gravitational infall, with the velocity dispersions being caused primarily by infall motions rather than random…
Star formation can be triggered by compression from wind or supernova driven shock waves that sweep over molecular clouds. Because these shocks will likely contain processed elements, triggered star formation has been proposed as an…
We numerically investigate dynamical and chemical properties of star clusters (open and globular clusters, and ``super star clusters'', SSC) formed in interacting/merging galaxies. The investigation is two-fold: (1) large-scale…
Star formation triggering mechanisms are reviewed, including the direct compression of clouds and globules, the compression and collapse of molecular clouds at the edges of HII regions and supernovae, the expansion and collapse of giant…
Spiral patterns in some disc galaxies have two arms in the centre, and three or more arms on the periphery. The same result is also obtained in numerical simulations of stellar and gaseous discs. We argue that such patterns may occur due to…
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…
Molecular clouds, the birthplaces of stars in galaxies, form dynamically from the diffuse atomic gas of the interstellar medium (ISM). The ISM is also threaded by magnetic fields which have a large impact on its dynamics. In particular,…
The organization of the interstellar medium in disk galaxies obeys the large scale dynamics set by kpc-size structures. Improving our knowledge of how the dense, molecular gas is distributed in a disk is an important step in our…
We demonstrate that the observationally inferred rapid onset of star formation after parental molecular clouds have assembled can be achieved by flow-driven cloud formation of atomic gas, using our previous three-dimensional numerical…
We investigate the formation and evolution of giant molecular clouds (GMCs) in a Milky-Way-like disk galaxy with a flat rotation curve. We perform a series of 3D adaptive mesh refinement (AMR) numerical simulations that follow both the…
Galactic spiral shocks are dominant morphological features and believed to be responsible for substructure formation within spiral arms in disk galaxies. They can also contribute a substantial amount of kinetic energy to the interstellar…
To investigate how molecular clouds react to different environmental conditions at a galactic scale, we present a catalogue of giant molecular clouds resolved down to masses of $\sim 10$~M$_{\odot}$ from a simulation of the entire disc of…
We analyze the motion of stars in the direction perpendicular to the galactic plane following a spiral arm passage. We show that the fast change in the vertical galactic potential causes a thermalized distribution to develop a distinctive…