Related papers: The Binary Second Sequence in Cluster Colour--Magn…
This paper is concerned with the spread in apparent magnitudes (or absolute magnitudes) of main-sequence stars in a star cluster. I specifically consider the effect of binary stars in broadening the main sequence. I present analytic and…
We apply probabilistic generative modelling of colour-magnitude diagrams to six young Galactic open star clusters and determine their mass functions, binary mass-ratio distributions, and the frequencies of binary stars. We find that younger…
About seventy percent of intermediate-age star clusters in the Large Magellanic Clouds have been confirmed to have broad main sequence, multiple or extended turn-offs and dual red giant clumps. The observed result seems against the…
The theoretical relation between the number of post main sequence stars from stellar populations and their total mass in investigated. This is used to derive some basic relations between the stellar number counts of stellar populations with…
Globular clusters contain many stars with surface abundance patterns indicating contributions from hydrogen burning products, as seen in the anti-correlated elemental abundances of e.g. sodium and oxygen, and magnesium and aluminium.…
Binary stars are common in star clusters and galaxies, but the detailed effects of binary evolution are not taken into account in some colour-magnitude diagram (CMD) studies. This paper studies the CMDs of twelve globular clusters via…
The fraction of binary stars is an important ingredient to interpret globular cluster dynamical evolution and their stellar population. We investigate the properties of main-sequence binaries measured in a uniform photometric sample of 59…
The total mass of a distant star cluster is often derived from the virial theorem, using line-of-sight velocity dispersion measurements and half-light radii, under the implicit assumption that all stars are single (although it is known that…
Almost all globular clusters (GCs) contain multiple populations consisting of stars with varying helium and light-element abundances. These populations include first-population stars, which exhibit similar chemical compositions to…
In this paper, some statistical distributions of wide pairs included in Double Star Catalogue are investigated. Frequency distributions and testing hypothesis are derived for some basic parameters of visual binaries. The results reached…
The identification of binary stars of different mass ratios in resolved stellar populations is a challenging task. We show how the photometric diagram constructed with the pseudo-colors (H-W2)-W1 vs W2-(BP-K) can be employed to estimate the…
Many, possibly most, stars form in binary and higher-order multiple systems. Therefore, the properties and frequency of binary systems provide strong clues to the star-formation process, and constraints on star-formation models. However,…
Approximately 10 per cent of star clusters are found in pairs, known as binary clusters. We propose a mechanism for binary cluster formation; we use N-body simulations to show that velocity substructure in a single (even fairly smooth)…
Based on the results of detailed population synthesis models, it was recently claimed that the clump of red giants in the colour-magnitude diagram (CMD) of composite stellar populations should present an extension to lower luminosities,…
Binaries are excellent astrophysical laboratories that provide us with direct measurements of fundamental stellar parameters. Compared to single isolated star, multiplicity induces new processes, offering the opportunity to confront our…
A number of scenarios for the formation of multiple populations in globular clusters (GCs) predict that second generation (2G) stars form in a compact and dense subsystem embedded in a more extended first-generation (1G) system. If these…
When modeling the population of merging binary black holes, analyses have generally focused on characterizing the distribution of primary (i.e. more massive) black holes in the binary, while simplistic prescriptions are used for the…
Globular Clusters (GCs) are known to host distinct stellar populations, characterized by different chemical compositions. Despite extensive research, the origin of these populations remains elusive. According to many formation scenarios,…
The dynamics of a close binary system of globular clusters is considered. It is shown that the star transfer process from one of the components to the other should lead to the decrease of dimension of the first cluster with simultaneous…
We analyse color-magnitude diagrams of eight Globular Clusters (GCs) in the outer Galactic Halo. Images were taken with the Wide Field Channel of the Advanced Camera for Survey and the Ultraviolet and Visual Channel of the Wide Field Camera…