相关论文: Precision age indicators that exploit chemically p…

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…

During the past decade, several studies reported a correlation between chemical abundances of stars and condensation temperature (also known as Tc trend). However, the real astrophysical nature of this correlation is still debated. The main…

We present a catalog of 2,990 extended sources in a 1deg x1deg area centered on M33 using the MegaCam camera on the 3.6m Canada-France-Hawaii telescope (CFHT). The catalog includes 599 new candidate stellar clusters, 204 previously…

Transiting planets around stars are discovered mostly through photometric surveys. Unlike radial velocity surveys, photometric surveys do not tend to target slow rotators, inactive or metal-rich stars. Nevertheless, we suspect that…

We introduce a practical methodology for investigating the star formation and chemical evolution history of a galaxy: age-divided mean stellar populations (ADPs) from full spectrum fitting. In this method, the mass-weighted mean stellar…

Studies during the last decade have revealed that nearly all Globular Clusters (GCs) host multiple populations (MPs) of stars with a distinctive chemical patterns in light elements. No evidence of such MPs has been found so far in…

Identifying stars formed in pristine environments (Pop III) within the first billion years is vital to uncovering the earliest growth and chemical evolution of galaxies. Pop III galaxies, however, are typically expected to be too faint and…

Asymptotic giant branch stars are essential contributors to the near and mid-IR emission of intermediate age (0.1-1Gyr old) stellar populations. Detecting this light sets constraints on the star formation history in galaxies and,…

Integrated spectra have been obtained of 31 star clusters in the Magellanic Clouds (MC) and of 4 Galactic globular clusters. The spectra cover the wavelength range 3500 -- 4700 Angstroms at a resolution of 3.2 Angstroms FWHM. The MC…

The conventional picture of coeval, chemically homogeneous, populous star clusters -- known as `simple stellar populations' (SSPs) -- is a view of the past. Photometric and spectroscopic studies reveal that almost all ancient globular…

In this contribution I will discuss fundamental stellar parameters as determined from young star clusters; specifically those with ages less than or approximately equal to that of the Pleiades. I will focus primarily on the use of stellar…

We identified star clusters in archived HST/WFPC2 images of the merger and ultra-luminous infrared galaxy NGC 6240, with the aim of investigating whether star cluster properties (luminosity, age and mass) in such an extreme environment…

It is widely accepted that individual Galactic globular clusters harbor two coeval generations of stars, the first one born with the `standard' alpha-enhanced metal mixture observed in field Halo objects, the second one characterized by an…

A fraction of brightest cluster galaxies (BCGs) shows bright emission in the UV and the blue part of the optical spectrum, which has been interpreted as evidence of recent star formation. Most of these results are based on the analysis of…

Eclipsing binary stars provide highly accurate measurements of the fundamental physical properties of stars. They therefore serve as stringent tests of the predictions of evolutionary models upon which most stellar age determinations are…

CONTEXT. A set of 20 extremely red galaxies at 2.5<z<3.8 with photometric features of old passive-evolving galaxies without dust, with stellar masses of ~10^{11} M_sun, have colors that could be related to passive-evolving galaxies with…

With the aim to corroborate the result of a search for chemically peculiar stars in the Large Magellanic Cloud (LMC) we present measurements obtained from CCD-imaging of two fields, one containing a young open cluster (NGC 1711). While for…

The possibility of identifying co-natal stars that have dispersed into the Galactic disc based on chemistry only is called strong chemical tagging. Its feasibility has been debated for a long time, with the promise of reconstructing the…

Combined spectroscopic abundance analyses of stable and radioactive elements can be applied for deriving stellar ages. The achievable precision depends on factors related to spectroscopy, nucleosynthesis, and chemical evolution. We quantify…

We present evolutionary population synthesis models for the study of the cool and luminous intermediate age stellar populations in resolved galaxies with particular emphasis on carbon star populations. We study the effects of the star…