相关论文: Clearing the Dust from Globular Clusters

We employ hydrodynamical simulations to investigate the underlying mechanism responsible for the low levels of gas and dust in globular clusters. Our models examine the competing effects of energy and mass supply from the various components…

We present Spitzer Space Telescope IRAC and MIPS observations of the galactic globular cluster M15 (NGC 7078), one of the most metal-poor clusters with a [Fe/H] = -2.4. Our Spitzer images reveal a population of dusty red giants near the…

How stellar clusters disrupt, and over what timescales, is intimately linked with how they form. Here, we review the theory and observations of cluster disruption, both the suggested initial rapid dissolution phase (infant mortality) and…

After the stars of a new, embedded star cluster have formed they blow the remaining gas out of the cluster. Especially winds of massive stars and definitely the on-set of the first supernovae can remove the residual gas from a cluster. This…

It is often argued that young stellar clusters suffer a significant infant mortality that is partly related to the expulsion of dust and gas in their early phases caused by radiation pressure from hot stars and supernovae. Near-infrared…

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…

Star formation within the central galaxies of galaxy clusters is often interpreted as being fueled by cooling of the hot intracluster medium. However, the star-forming gas is dusty, and Spitzer spectra show that the dust properties are…

Stacked analyses of galaxy clusters at low-to-intermediate redshift show signatures attributable to dust, but the origin of this dust is uncertain. We test the hypothesis that the bulk of cluster dust derives from galaxy ejecta. To do so,…

Globular clusters host complex stellar populations whose chemical signatures suggest early (3 Myr - 1 Gyr) retention and reprocessing of stellar ejecta, yet direct evidence for intracluster gas is lacking. Here we present a unified…

Globular cluster stars evolving off the main sequence are known to lose mass, and it is expected that some of the lost material should remain within the cluster as an intracluster medium (ICM). Most attempts to detect such an ICM have been…

Star clusters stand at the intersection of much of modern astrophysics: the interstellar medium, gravitational dynamics, stellar evolution, and cosmology. Here we review observations and theoretical models for the formation, evolution, and…

We created artificial color-magnitude diagrams of Monte Carlo dynamical models of globular clusters, and then used observational methods to determine the number of blue stragglers in those clusters. We compared these blue stragglers to…

Gas expulsion is a central concept in some of the models for multiple populations and the light-element anticorrelations in globular clusters. If the star formation efficiency was around 30 per cent and the gas expulsion happened on the…

To a great extent, our understanding of the life cycle of dust is based on the observational and theoretical studies of the Milky Way and the Magellanic Clouds, which will be the topic of this contribution. Over past years, a large volume…

The results of N-body simulations of the expulsion of residual gas from young globular clusters are presented. Globular clusters with a variety of initial masses, Galactocentric radii, concentration and initial mass function slope with star…

Star clusters are often used as tracers of major star formation events in external galaxies as they can be studied up to much larger distances than individual stars. It is vital to understand their evolution if they are used to derive, for…

We report the discovery of four dusty cometary tails around low mass stars in two young clusters belonging to the W5 star forming region. Fits to the observed emission profiles from 24 micron observations with the Spitzer Space Telescope…

We have conducted an archival Spitzer study of 38 early-type galaxies (ETGs) in order to determine the origin of the dust in approximately half of this population. Our sample galaxies generally have good wavelength coverage from 3.6um to…

We report on five years of 3-5 micron photometry measurements obtained by warm Spitzer to track the dust debris emission in the terrestrial zone of HD 166191 in combination with simultaneous optical data. We show that the debris production…

We have carried out a large grid of N-body simulations in order to investigate if mass-loss as a result of primordial gas expulsion can be responsible for the large fraction of second generation stars in globular clusters (GCs) with…