相关论文: Predicted HST FOC and broad band colours for young…
Theoretical integrated broad-band colors ranging from far-UV to near-IR have been computed for old stellar systems from our evolutionary population synthesis code. These models take into account, for the first time, the detailed systematic…
We present a comprehensive analysis of the ability of current stellar population models to reproduce the optical (ugriz) and near infra-red (JHK) colours of a small sample of well-studied nearby elliptical and S0 galaxies. We find broad…
(abridged) We investigate biases in cluster ages and [Fe/H] estimated from the (V-K)-(V-I) diagram, arising from inconsistent Horizontal Branch morphology, metal mixture, treatment of core convection between observed clusters and the…
We investigate the uncertainties in the synthetic integrated colors of simple stellar populations. Three types of uncertainties are from the stellar models, the population synthesis techniques, and from the spectral libraries. Despite some…
Several population synthesis models now predict integrated colors of simple stellar populations in the mid-infrared bands. To date, the models have not been extensively tested in this wavelength range. In a comparison of the predictions of…
We present an empirical assessment of the use of broadband optical colours as age indicators for unresolved extragalactic clusters and investigate stochastic sampling effects on integrated colours. We use the integrated properties of…
We have measured an extensive set of UBVRIJHK colors for M31 globular clusters [Barmby et al. 2000]. We compare the predicted simple stellar population colors of three population synthesis models to the intrinsic colors of Galactic and M31…
We report on the properties of 89 low mass star clusters located in the vicinity of luminous young clusters (blue globulars) in the disk of M31. 82 of the clusters are newly detected. We have determined their integrated magnitudes and…
We briefly review the main features in the broad-band colour evolution of star clusters, over the complete age interval from 10^7 to 10^(10) yr. The emphasis is in the problem of age-dating distant young clusters (<2 Gyr) from their…
We present integrated JHK_s 2MASS photometry and a compilation of integrated-light optical photoelectric measurements for 84 star clusters in the Magellanic Clouds. These clusters range in age from ~200 Myr to >10 Gyr, and have [Fe/H]…
We examine the influence of stochastic effects on the integrated near-infrared light of star clusters with ages between 7.5<log(t)<9.25. To do this, we use stellar evolution models and a Monte Carlo technique to simulate the effects of…
[Abridged] We present new model predictions for 16 Lick absorption line indices from Hdelta through Fe5335, and UBV colors for single stellar populations (SPs) with ages ranging between 1 and 15 Gyr, [Fe/H] ranging from -1.3 to +0.3, and…
The presence of an extended blue horizontal branch (HB) in a stellar population is known to affect the age inferred from spectral fitting to stellar population synthesis models. However, most population synthesis models still rely on…
The restframe mid-ultraviolet spectral region (2000-3200 A) is important in analyzing the stellar populations of the "red envelope" systems observed at high redshifts. Here, we explore the usefulness of the mid-UV for determining ages and…
We present Monte Carlo models of open stellar clusters with the purpose of mapping out the behavior of integrated colors with mass and age. Our cluster simulation package allows for stochastic variations in the stellar mass function to…
(ABRIDGED) We assess the systematic uncertainties in (young) cluster age, mass, and - to a lesser extent - extinction and metallicity determinations, based on broad-band imaging observations with the Hubble Space Telescope. Our aim here is…
Observations of Young Star Cluster ({\bf YSC}) systems in interacting galaxies are reviewed with particular emphasis on their Luminosity Functions ({\bf LF}) and colour distributions. A few spectroscopic abundance measurements are…
We present an analysis of compact star clusters in deep HST/WFPC2 images of NGC 1275. B and R band photometry of roughly 3000 clusters shows a bimodality in the B-R colors, suggesting that distinct old and young cluster populations are…
Using a widely used stellar population synthesis model, we study the ability of using pairs of AB system colours to break the well-known stellar age--metallicity degeneracy and give constraints on the two stellar-population parameters (age…
We present a new set of stellar interior and synthesis models for predicting the integrated emission from stellar populations in star clusters and galaxies of arbitrary age and metallicity. This work differs from existing spectral synthesis…