Related papers: The physical properties of Cluster Chains
We argue that rich star clusters take at least several local dynamical times to form, and so are quasi-equilibrium structures during their assembly. Observations supporting this conclusion include morphologies of star-forming clumps,…
We address the nature and origin of Super Star Clusters (SSCs) discovered by Holtzman et al. (1992) within a radius of $\sim$$5\,\rm kpc$ from the center of NGC 1275, the giant elliptical galaxy at the center of the Perseus Cluster. We show…
The genesis of spheroids is central to our understanding of galaxy formation -- they are relatively simple systems, containing about half the stellar mass of the Universe. A major subset of spheroids, massive elliptical galaxies, are…
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…
Observational and theoretical arguments support the idea that violent events connected with $AGN$ activity and/or intense star forming episodes have played a significant role in the early phases of galaxy formation at high red shifts. Being…
The Orion Nebula Cluster (ONC) is the most massive region of active star formation within a kpc of the Sun. Using Gaia DR3 parallaxes and proper motions, we examine the bulk motions of stars radially and tangentially relative to the cluster…
The ONC appears to be unusual on two grounds: The observed constellation of the OB stars of the entire Orion Nebula cluster and its Trapezium at its centre implies a time-scale problem given the age of the Trapezium, and an IMF problem for…
The origin of {\omega} Centauri remains one of the key open problems in stellar dynamics and chemical evolution. Its large abundance spreads and multiple populations suggest a formation history more complex than that of a typical globular…
We analyze high quality, complete stellar catalogs for four young (roughly 1 Myr) and nearby (within ~300 pc) star-forming regions: Taurus, Lupus3, ChaI, and IC348, which have been previously shown to have stellar groups whose properties…
We explore, through a simplified, semi-analytic model, the formation of dense clusters containing massive stars. The parent cloud spawning the cluster is represented as an isothermal sphere. This sphere is in near force balance between…
Nuclear star clusters (NSCs) are found in at least 70% of all galaxies, but their formation path is still unclear. In the most common scenarios, NSCs form in-situ from the galaxy's central gas reservoir, through merging of globular clusters…
Using the APM cluster data we investigate whether the dynamical status of clusters is related to the large-scale structure of the Universe. We find that cluster substructure is strongly correlated with the tendency of clusters to be aligned…
In recent years a correlation between mass accretion rates onto new-born stars and their proto-planetary disc masses was detected in nearby young star-forming regions. Although such a correlation can be interpreted as due to…
The standard picture of accretion is a steady flow of matter from the disc onto the young star - a concept which assumes the star-disc system to be completely isolated. However, in a dense cluster environment star-disc systems do interact…
Using new proper motion data from recently published catalogs, we revisit the membership of previously identified members of the Upper Scorpius association. We confirmed 750 of them as cluster members based on the convergent point method,…
Star formation is triggered in essentially three ways: (1) the pressures from existing stars collect and squeeze nearby dense gas into gravitationally unstable configurations, (2) random compression from supersonic turbulence makes new…
We study the links between star formation history and structure for a large mass-selected galaxy sample at 0.05 < z_phot < 0.30. The galaxies inhabit a very broad range of environments, from cluster cores to the field. Using HST images, we…
We discuss the mechanism of cluster formation in hierarchically collapsing molecular clouds. Recent evidence, both observational and numerical, suggests that molecular clouds (MCs) may be undergoing global, hierarchical gravitational…
Observations and theory suggest that star clusters can form in a subvirial (cool) state and are highly substructured. Such initial conditions have been proposed to explain the level of mass segregation in clusters through dynamics, and have…
We review topics related to the dispersal of young stars from their birth-sites, and focus in particular on the entourage of young stars related to the ongoing star-formation event in the Sco-Cen OB association. We conduct a follow-up…