Related papers: Towards Multiple-Star Population Synthesis
From an initial sample of a few hundred stars selected for an Hipparcos program, a subsample of 33 objects with direct determination of their effective temperature, bolometric magnitude and [Fe/H] has been derived. An accurate observational…
Recently, with the goal to study multiplicity of chemically peculiar stars, we carried out a survey of 40 stars using diffraction limited near infrared (IR) imaging with NAOS-CONICA (NACO) at the VLT. Here, we announce the detection of 27…
The conditions required for massive star formation are debated, particularly whether massive stars must form in conjunction with massive clusters. Some authors have advanced the view that stars of any mass (below the total cluster mass) can…
We have measured the 3.6 micron luminosity and mass evolution of about 1000 galaxies in 32 clusters at 0.2<z<1.25 with a special attention to methodological issues, as emphasized in this proceeding contribution. We find that the luminosity…
Population synthesis is used to model the number of neutron stars in globular clusters that are observed as LMXBs and millisecond PSRs. The dynamical interaction between binary and single stars in a GC are assumed to take place with a…
Photometric calibration to 5% accuracy is frequently needed at arbitrary celestial locations; however, existing all-sky astronomical catalogs do not reach this accuracy and time consuming photometric calibration procedures are required. I…
The paper deals with the conditions required to form at least two stellar generations in globular clusters under the constraints generated by feedback from massive stars as well as radiative cooling and the metallicity of the primordial…
Discussion of the designation of multiple-star components leads to a conclusion that, apart from components, we need to designate systems and centers-of-mass. The hierarchy is coded then by simple links to parent. This system is adopted in…
We exploit the astro-photometric dataset of the multi-epoch infrared parallel field of a $\textit{Hubble Space Telescope}$ Large Programme aimed at studying the faintest stars of the globular cluster NGC$\,$6752 to determine the luminosity…
The ``MORPHS'' group has obtained an extensive spectroscopic dataset of galaxies in the fields of 10 rich clusters at $0.37<z<0.56$; the stellar population properties of about 700 objects have been determined from a detailed analysis of…
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…
Recent surveys of star forming regions have shown that most stars, and probably all massive stars, are born in dense stellar clusters. The mechanism by which a molecular cloud fragments to form several hundred to thousands of individual…
In order to build more realistic single stellar population (SSP) models with variable alpha-enhancement, we have recently determined [Mg/Fe] in a uniform scale with a precision of about 0.1 dex for 752 stars in the MILES empirical library.…
Globular clusters were thought to be simple stellar populations, but recent photometric and spectroscopic evidence suggests that the clusters' early formation history was more complicated. In particular, clusters show star-to-star abundance…
Binary stars are common and it is necessary to model stellar populations using binary stars. We introduce a method to model binary-star stellar populations quickly. The method can also be used to model single-star stellar populations. The…
HST is very well tailored for observations of extragalactic star clusters. One obvious reason is HST's high spatial resolution, but equally important is the wavelength range offered by the instruments on board HST, in particular the blue…
Recent studies have started to cast doubt on the assumption that most stars are formed in clusters. Observational studies of field stars and star cluster systems in nearby galaxies can lead to better constraints on the fraction of stars…
We present a study of the effect of crowding on stellar photometry. We develop an analytical model through which we are able to predict the error in magnitude and color for a given star for any combination of telescope resolution, stellar…
Integrated light from distant galaxies is often compared to stellar population models via the equivalent widths of spectral features--spectral indices--whose strengths rely on the abundances of one or more elements. Such comparisons hinge…
We explore the relative percentages of binary systems and higher-order multiples that are formed by pure stellar dynamics, within a small subcluster of $N$ stars. The subcluster is intended to represent the fragmentation products of a…