相关论文: Completing the Massive Star Population: Striking I…
The properties of young star clusters formed within a galaxy are thought to vary in different interstellar medium (ISM) conditions, but the details of this mapping from galactic to cluster scales are poorly understood due to the large…
Runaway stars are OB-type stars ejected from their birthplace with large peculiar velocities. The leading hypothesis addressed in their formation includes the supernova ejection mechanism and the dynamic ejection scenario. Identification of…
Outside of the known star clusters in the Galactic Center, a large number of evolved massive stars have been detected; but their origins remain uncertain. We present a spectroscopic study of eight such stars, based on new Gemini GNIRS and…
Context: Field stars are not always single stars, but can often be found in bound double systems. Since binary frequencies in the birth places of stars, young embedded clusters, are sometimes even higher than on average the question arises…
Current observational constraints on the dynamical evolution of star clusters are reviewed. Theory and observations now agree nicely on the mass dependency and time scales for disruption of young star clusters in galactic disks, but many…
Galactic star formation scaling relations show increased scatter from kpc to sub-kpc scales. Investigating this scatter may hold important clues to how the star formation process evolves in time and space. Here, we combine different…
The Small Magellanic Cloud (SMC) has recently been found to harbour more than two hundred per cent increase of its known cluster population. We provide here with solid evidence that such an unprecedented number of clusters could be largely…
The initial mass function (IMF) succinctly characterizes a stellar population, provides a statistical measure of the end result of the star-formation process, and informs our under- standing of the structure and dynamical evolution of…
Blue straggler stars are unique main-sequence stars that appear more luminous, hotter, and therefore younger, than their coeval counterparts. In star clusters, these stars are located above the cluster turn-off in the Hertzsprung-Russell…
Globular Cluster (GC) formation seems to be a widespread mode of star formation in extreme starbursts triggered by strong interactions and mergers of massive gas-rich galaxies. We use our detailed chemically consistent evolutionary…
An increasing number of photometric observations of multiple stellar populations in Galactic globular clusters is seriously challenging the paradigm of GCs hosting single, simple stellar populations. These multiple populations manifest…
Over the past ten years, there has been a revolution in our understanding of massive young stellar clusters in the Galaxy. Initially, there were no known examples having masses $>10^4$, yet we now know that there are at least a half dozen…
Recent progress in studies of globular clusters has shown that they are not simple stellar populations, being rather made of multiple generations. Evidence stems both from photometry and spectroscopy. A new paradigm is then arising for the…
We study the stellar cluster population in two adjacent fields in the nearby, face-on spiral galaxy, M83, using WFC3/HST imaging. The clusters are selected through visual inspection to be centrally concentrated, symmetric, and resolved on…
The ensemble of all star clusters in a galaxy constitutes its star cluster system. In this review, the focus of the discussion is on the ability of star clusters, particularly the systems of old massive globular clusters (GCSs), to mark the…
Massive stars are the drivers of star formation and galactic dynamics due to their relatively short lives and explosive demises, thus impacting all of astrophysics. Since they are so impactful on their environments, through their winds on…
Low mass star formation regions are unlikely to fully populate their initial mass functions, leading to a deficit of massive stars. In binary stellar populations, the full range of binary separations and mass ratios will also be…
The evolution of magnetic fields in Ap stars during the main sequence phase is presently mostly unconstrained by observation because of the difficulty of assigning accurate ages to known field Ap stars. We are carrying out a large survey of…
We identify a vertical extension of the red clump stars in the color magnitude diagram (CMD) of a section of the Large Magellanic Cloud (LMC). After subtracting the principal red clump component, we find a peak in the residual stellar…
The presence of magnetic fields at the surfaces of many massive stars has been suspected for decades, to explain the observed properties and activity of OB stars. However, very few genuine high-mass stars had been identified as magnetic…