相关论文: Ages and Age Spreads in Young Stellar Clusters

The next generation near- and mid-infrared Galactic surveys will yield a large number of new highly obscured star clusters. Detailed characterization of these new objects with spectroscopy is time-consuming. Diagnostic tools that will be…

The heated debate on the importance of stellar rotation and age spreads in massive star clusters has just become hotter by throwing stellar variability into the mix.

Aims. We study the connection between spatially resolved star formation and young star clusters across the disc of M51. Methods. We combine star cluster data based on B, V, and I-band Hubble Space Telescope ACS imaging, together with new…

Over the next decade, observations conducted with ALMA and the SKA will reveal the process of mass assembly and accretion onto young stars and will be revolutionary for studies of star formation. Here we summarise the capabilities of ALMA…

Context: Knowledge of the age distribution of stars in young clusters and associations is crucial to constrain models of star formation. HR diagrams of different young clusters and associations suggest the presence of age spreads, but the…

Surface temperature distribution of horizontal-branch (HB) stars is very sensitive to age in old stellar systems, which makes it an attractive age indicator. In this paper, we present the recent revision of our model calculations for the HB…

We present an unbiased method for evaluating the ranges of ages and metallicities which are allowed by the photometric properties of the stellar populations that dominate the light of early-type galaxies in clusters. The method is based on…

We present a grid of evolutionary calculations for metal-poor low-mass stars for a variety of initial helium and metal abundances. The intention is mainly to provide a database for deriving directly stellar ages of halo and globular cluster…

(Abridged) We study the nuclear star clusters in spiral galaxies of various Hubble types using spectra obtained with STIS on-board HST. We observed the nuclear clusters in 40 galaxies, selected from two previous HST/WFPC2 imaging surveys.…

Stellar ages are key for determining the formation history of the Milky Way, but are difficult to measure precisely. Furthermore, methods that use chemical abundances to infer ages may entangle the intrinsic evolution of stars with the…

The recent identification of several groups of young stars within 100 parsecs of the Sun has generated widespread interest. Given their proximity and possible age differences, these systems are ideally suited for detailed studies of disk…

The environments around star clusters evolve as stellar feedback reshapes the interstellar medium and dynamical processes reorganize the structure of the surrounding stellar field. As approximately single-age populations, star clusters can…

Various methods for age dating globular clusters in ellipticals are presented. We first present spectroscopy of individual globular clusters (feasible with the advent of the 10m-class telescopes), and the measurement of Balmer line indices.…

We present colour-magnitude diagrams for two rich (~10^4 Msun) Large Magellanic Cloud star clusters with ages ~10^7 years, constructed from optical and near-infrared data obtained with the Hubble Space Telescope. These data are part of an…

Establishing ages for young clusters is key for properly tracking the star formation history of a region. In this paper we investigate a new approach to estimating ages for young populations, based on the well-founded assumption that the…

An overview of our current understanding of the formation and evolution of star clusters is given, with main emphasis on high-mass clusters. Clusters form deeply embedded within dense clouds of molecular gas. Left-over gas is cleared within…

The main sequence turnoff luminosity is the best stellar `clock' which can be used to determine the absolute ages of globular clusters. This is due to the fact that it is generally assumed that the luminosity and lifetimes of main sequence…

Galaxy clusters are the largest structures in Universe. They are very important as both cosmological probes and astrophysical laboratories. Several methods have been developed to detect galaxy clusters with different techniques (optical,…

We present preliminary results from our on-going survey of Galactic globular clusters relative ages. The investigation is based on V,I images obtained at the ESO and La Palma telescopes, which make up the largest homogenous photometric…

The average age difference between pairs of star clusters in the Large Magellanic Clouds increases with their separation as the ~0.35 power. This suggests that star formation is hierarchical in space and time. Small regions form stars…