相关论文: Very massive stars in not so massive clusters
Mass segregation is seen in many star clusters, but whether massive stars form in the center of a cluster or migrate there dynamically is still debated. N-body simulations have shown that early dynamical mass segregation is possible when…
An unsettled question concerning the formation and distribution of massive stars is whether they must be born in massive clusters and, if found in less dense environments, whether they must have migrated there. With the advent of wide-area…
Hydrodynamical simulations of turbulent molecular clouds show that star clusters form from the hierarchical merger of several sub-clumps. We run smoothed-particle hydrodynamics simulations of turbulence-supported molecular clouds with mass…
The formation of massive stars is an outstanding problem in stellar evolution. However, it is expected that they are (predominantly) born in heirarchical environments within massive young clusters, which in turn are located within larger…
This review summarises the main properties of Young Massive Clusters (YMCs), including their population properties, particularly focusing on extragalactic cluster samples. We discuss potential biases and caveats that can affect the…
We propose that bound, young massive stellar clusters form from dense clouds that have escape speeds greater than the sound speed in photo-ionized gas. In these clumps, radiative feedback in the form of gas ionization is bottled up,…
Spectroscopic multiplicity surveys of O stars in young clusters and OB associations have revealed that a large portion ($\sim$ 70%) of these massive stars (M$_{i}$ $\gt$ 15 $M_{\odot}$) belong to close and short-period binaries (physical…
Most of massive stars form in binary or higher-order systems in clumpy, sub-structured clusters. In the very first phases of their life, these stars are expected to interact with the surrounding environment, before being released to the…
We performed numerical simulations of dynamical encounters between hard massive binaries and a very massive star (VMS; formed through runaway mergers of ordinary stars in the dense core of a young massive star cluster), in order to explore…
The interplay between the formation of stars, stellar feedback and cloud properties strongly influences the star formation history of giant molecular clouds. The formation of massive stars leads to a variety of stellar clusters, ranging…
In spite of significant recent and ongoing research efforts, most of the early evolution and long-term fate of young massive star clusters remain clouded in uncertainties. Here, I discuss our understanding of the initial conditions of star…
The surface brightness profiles of globular clusters are conventionally described with the well-known King profile. However, observations of young massive clusters (YMCs) in the local Universe suggest that they are better fit by simple…
Massive OB stars play an important role in the evolution of molecular clouds and star forming regions. The OB stars both photo--ionize molecular gas as well as sweep up and compress interstellar gas through winds, ionization fronts, and…
Most stars do not form in isolation but as part of a cluster comprising anywhere between a few dozen to several million stars with stellar densities ranging from 0.01 to several 10$^5$ \Msun pc$^{-3}$. The majority of these clusters…
Young massive clusters (YMCs) are recently formed astronomical objects with unusually high star formation rates. We propose the collision of giant molecular clouds (GMCs) as a likely formation mechanism of YMCs, consistent with the YMC…
Observations and high-resolution hydrodynamical simulations indicate that massive star clusters form through a complex hierarchical assembly. We use simulations including post-Newtonian dynamics (the BIFROST code) and stellar evolution (the…
The intermediate age star cluster W3 (age ~ 300-500 Myr) in NGC 7252 is the most luminous star cluster known to date with a dynamical mass estimate of 8 +/- 2 x 10^7 M_sun. With an effective radius of about 17.5 pc and a velocity dispersion…
Many galaxies host pronounced circumnuclear starbursts, fuelled by infalling gas. Such activity is expected to drive the secular evolution of the nucleus and generate super winds, while the intense radiation fields and extreme gas and…
We provide a set of analytic fits to the radii of pre-mainsequence stars in the mass range 0.1 < M/Msun < 8.0. We incorporate the formulae in N-body cluster models for evolution from the beginning of pre-main sequence. In models with 1,000…
We present an analysis of the spatial distribution of various stellar populations within the Large Magellanic Cloud. We combine mid-infrared selected young stellar objects, optically selected samples with mean ages between ~9 and ~1000 Myr,…