相关论文: Runaway stars masquerading as star formation in ga…
Recent observations have revealed massive galactic molecular outflows that may have physical conditions (high gas densities) required to form stars. Indeed, several recent models predict that such massive galactic outflows may ignite star…
Roughly ten per cent of OB stars are kicked out of their natal clusters before ending their life as supernovae. These so-called runaway stars can travel hundreds of parsecs into the low-density interstellar medium, where momentum and energy…
Runaway stars are stars observed to have large peculiar velocities. Two mechanisms are thought to contribute to the ejection of runaway stars, both involve binarity (or higher multiplicity). In the binary supernova scenario a runaway star…
Several models have predicted that stars could form inside galactic outflows and that this would be a new major mode of galaxy evolution. Observations of galactic outflows have revealed that they host large amounts of dense and clumpy…
Runaway stars ejected from the Galactic disk populate the halo of the Milky Way. To predict the spatial and kinematic properties of runaways, we inject stars into a Galactic potential, compute their trajectories through the Galaxy, and…
We have collected from the literature a list of early-type stars, situated at large distances from the galactic plane, for which evidence of youth seems convincing. We discuss two possible formation mechanisms for these stars: ejection from…
We present an investigation of the known sample of runaway stars. The orbits of these stars are traced back to their origin in the Galactic disc. The velocity distribution of these stars is compared to theoretical predictions. We conclude…
A significant fraction of massive stars in the Milky Way and other galaxies are located far from star clusters. It is known that some of these stars are runaways and therefore most likely were formed in embedded clusters and then ejected…
Two main mechanisms have classically been proposed for the formation of runaway stars. In the binary supernova scenario (BSS), a massive star in a binary explodes as a supernova, ejecting its companion. In the dynamical ejection scenario, a…
Runaway stars can result from core-collapse supernovae in multiple stellar systems. If the supernova disrupts the system, the companion gets ejected with its former orbital velocity. A clear identification of a runaway star can yield the…
We demonstrate that stars beyond the virial radii of galaxies may be generated by the gravitational impulse received by a satellite as it passes through the pericenter of its orbit around its parent. These stars may become energetically…
Although the basic physics of star formation is classical, numerical simulations have yielded essential insights into how stars form. They show that star formation is a highly nonuniform runaway process characterized by the emergence of…
I review observational studies of the large-scale star formation process in nearby galaxies. A wealth of new multi-wavelength data provide an unprecedented view on the interplay of the interstellar medium and (young) stellar populations on…
Close encounters and physical collisions between stars in young dense clusters may lead to the formation of very massive stars and black holes via runaway merging. We examine critically some details of this process, using N-body simulations…
A significant proportion of Milky Way stars are born in stellar clusters, which dissolve over time so that the members become part of the disc and halo populations of the Galaxy. In the present work we will assume that these young stellar…
Observations have suggested that galactic outflows contain substantial amounts of dense and clumpy molecular gas, creating favourable conditions for igniting star formation. Indeed, theoretical models and hydrodynamical simulations have…
Massive stars are predominantly born in stellar associations or clusters. Their radiation fields, stellar winds, and supernovae strongly impact their local environment. In the first few million years of a cluster's life, massive stars are…
We present the methods and preparatory work for our study of the collisional runaway scenario to form a very massive star (VMS, M > 400 Msun) at the centre of a young, compact stellar cluster. In the first phase of the process, a very dense…
The evolution of young compact star clusters is studied using N-body simulations in which both stellar evolution and physical collisions between stars are taken into account. The initial conditions are chosen to represent R136, a compact…
High-mass stars are commonly found in stellar clusters promoting the idea that their formation occurs due to the physical processes linked with a young stellar cluster. It has recently been reported that isolated high-mass stars are present…