相关论文: The stellar to sub-stellar masses transition in 47…

Globular clusters (GCs) are known to host multiple stellar populations showing chemical anomalies in the content of light elements. The origin of such anomalies observed in Galactic GCs is still debated. Here we analyse data compiled from…

In this thesis we study several aspects of dynamical evolution of stellar clusters. The results of more than 200 simulations of single-mass star clusters with different initial total mass, half-mass radius and galactocentric distance, are…

We present a new method to estimate the fraction of stars with chemical composition of first and second(s) generation(s) currently hosted in Galactic globular clusters (GCs). We compare cluster and field stars of similar metallicity in the…

We present deep Hubble Space Telescope optical imaging observations of two Galactic globular clusters, 47 Tuc and M15, using the Space Telescope Imaging Spectrograph (STIS) longpass (LP) filter and the Wide Field and Planetary Camera 2…

The globular cluster (GC) 47 Tuc has recently been proposed to host an intermediate-mass black hole (IMBH) or a population of stellar-mass black holes (BHs). To shed light on its dark content, we present an application of self-consistent…

(Abridged) The dynamical ejection of stars from star clusters affects the shape of the stellar mass function (MF) in these clusters, because the escape probability of a star depends on its mass. The objective of this paper is to provide and…

Using 3.6$\mu$m images of 97 early-type galaxies, we develop and verify methodology to measure globular cluster populations from the S$^4$G survey images. We find that 1) the ratio, T$_{\rm N}$, of the number of clusters, N$_{\rm CL}$, to…

The distinction of the stellar content in globular clusters (GCs) in multiple stellar populations characterized by different amounts of proton-capture elements has been well assessed since a long time. On the other hand, the existence of…

We study the stellar mass content of massive haloes in the redshift range 0.86<z<1.34, by measuring: (1) The stellar mass in the central galaxy versus total dynamical halo mass. (2) The total stellar mass (including satellites) versus total…

We present the results of the analysis of deep photometric data of 32 Galactic globular clusters. We analysed 69 parallel field images observed with the Wide Field Channel of the Advanced Camera for Surveys of the Hubble Space Telescope…

It is now commonly accepted that globular clusters (GCs) have undergone a complex formation and that they host at least two stellar generations. This is a recent paradigm and is founded on both photometric and spectroscopic evidence. We…

In HST Cycle 17, we imaged the well known globular star cluster 47 Tucanae for 121 orbits using ACS and both the UVIS and IR channels of WFC3 (GO-11677, PI - H. Richer). This unique data set was obtained to address many scientific questions…

Around the turn of the last century, star clusters of all kinds were considered "simple" stellar populations. Over the past decade, this situation has changed dramatically. At the same time, star clusters are among the brightest stellar…

Stellar mass governs stellar evolution and the distribution of stellar masses plays a central role in the dynamical evolution of stellar clusters. Using high-precision astrometry and photometry from Gaia DR3, we investigate mass segregation…

We obtain stringent constraints on the actual efficiency of mass loss for red giant branch stars in the Galactic globular cluster 47 Tuc, by comparing synthetic modeling based on stellar evolution tracks with the observed distribution of…

A search for stellar clusters has been carried out in 18 nearby spiral galaxies, using HST/WFPC2 archive images. All of the galaxies have previously been imaged from the ground in UBVI. A catalogue of structural parameters, photometry and…

The globular cluster 47~Tucanae (47~Tuc) is one of the most massive star clusters in the Milky Way and is exceptionally rich in exotic stellar populations. For several decades it has been a favorite target of observers, and yet it is…

We compare the existent methods including the minimum spanning tree based method and the local stellar density based method, in measuring mass segregation of star clusters. We find that the minimum spanning tree method reflects more the…

The globular cluster 47 Tucanae is well studied but it has many characteristics that are unexplained, including a significant rise in the velocity dispersion profile at large radii, indicating the exciting possibility of two distinct…

Globular star clusters are among the first stellar populations to have formed in the Milky Way, and thus only a small sliver of their initial spectrum of stellar types are still burning hydrogen on the main-sequence today. Almost all of the…