相关论文: Young Globular Clusters and Dwarf Spheroidals
Dwarf spheroidal galaxies are regarded as the basic building blocks in the formation of larger galaxies and are believed to be the most dark matter dominated systems known in the Universe. There are several models that attempt to explain…
We have investigated the formation of globular cluster (GC) systems in the fiducial semi-analytic galaxy formation model of Cole et al. We assume that GCs are formed at high-redshift (z > 5) in proto-galactic fragments, and during the…
The relations between the luminosities $M_{V}$, the metallicities $[Fe/H]$, the Galactocentric radii $R$, and the central concentration indices $c$ of Galactic globular clusters are discussed. It is found that the most luminous clusters…
Photometry of a large field around the young globular cluster Palomar 12 has revealed the main-sequence of a low surface-brightness stellar system. This main-sequence is indicative of a stellar population that varies significantly in…
We present a review of the present state of knowledge regarding the relative ages of Galactic globular clusters. First, we discuss the relevant galaxy formation models and describe the detailed predictions they make with respect to the…
We investigate a scenario where the formation of Globular Clusters (GCs) is triggered by high-speed collisions between infalling atomic-cooling subhalos during the assembly of the main galaxy host, a special dynamical mode of star formation…
Globular clusters in most large galaxies are a mixture of metal-poor and metal-rich (bimodal), but the halo stars are almost entirely metal-rich. This and other lines of evidence argue that the metal-poor globular clusters formed within…
Globular clusters formed in galactic mergers (e.g., The Antennae) can now be studied at different stages of their evolution. In young merger remnants (e.g., NGC 7252) these "second-generation" globulars appear by the hundreds as young halo…
Young star clusters in interacting galaxies are often found in groups or clusters of star clusters containing up to 100 single clusters. In our project we study the future fate of these clusters of star clusters. We find that the star…
This paper explores if, and to what an extent, the stellar populations of early type galaxies can be traced through the colour distribution of their globular cluster systems. The analysis, based on a galaxy sample from the Virgo ACS data,…
This paper explores the quantitative connection between globular clusters and the diffuse stellar population of the galaxies they are associated with. Both NGC 1399 and NGC 4486 (M87) are well suited for this kind of analysis due to their…
Young stars form on a wide range of scales, producing aggregates and clusters with various degrees of gravitational self-binding. The loose aggregates have a hierarchical structure in both space and time that resembles interstellar…
Luminosities and tidal radii of globular clusters have been used to estimate the perigalactic distances P of well-observed Galactic globulars that do not have collapsed cores. It is found that the cluster metallicity [Fe/H] correlates…
This work reports the discovery of three new globular clusters (GCs) towards the Galactic bulge - Camargo 1107, 1108, and 1109. The discovery was made using the WISE, 2MASS, VVV, and Gaia-DR2 photometry. The new findings are old (12.0-13.5…
More than half of all stars in the local Universe are found in massive spheroidal galaxies, which are characterized by old stellar populations with little or no current star formation. In present models, such galaxies appear rather late as…
Star clusters can be found in galaxy mergers, not only in central regions, but also in the tidal debris. In both the Eastern and Western tidal tails of NGC 3256 there are dozens of young star clusters, confirmed by their blue colors and…
We present a spectroscopic search for halo field stars that originally formed in globular clusters. Using moderate-resolution SDSS-III/SEGUE-2 spectra of 561 red giants with typical halo metallicities (-1.8 < [Fe/H] < -1.0), we identify 16…
Globular clusters (GCs) provide one way of determining when the most important periods of star formation in dwarf elliptical (dE) galaxies occurred. Thus, they are also useful for comparing the star formation histories of dwarf and giant…
I discuss the chemical evolution of star clusters, with emphasis on old globular clusters, in relation to their formation histories. Globular clusters clearly formed in a complex fashion, under markedly different conditions from any younger…
We present evidence for the existence of an old stellar halo in the dwarf irregular galaxy WLM, an isolated member of the Local Group. The halo consists of population-II stars, with low metallicities and age $\geq 10^{10}$yr. The finding of…