EPoS Contribution
EPoS Contribution
The hierarchical nature of star formation

Dimitrios Gouliermis
Zentrum fuer Astronomie der Universitaet Heidelberg, Institut fuer Theoretische Astrophysik, Heidelberg, Germany
Star formation on galactic scales occurs over a variety of structures, from large stellar complexes and aggregates to smaller OB associations and embedded clusters, which themselves often show substructure. All these stellar systems are not independent entities, but rather appear to constitute a self-similar structuring pattern, very similar to the hierarchical structuring behavior of the interstellar matter (ISM). We currently perform an investigation of the large-scale clustering of young hot stars in galaxies of the Local Group, which aims at the assessment of the relation between the hierarchy in stellar structures and that of the ISM. Our results from a quantitative cluster analysis, based on the nearest-neighbor and minimum spanning tree techniques, on the Small Magellanic Cloud and NGC 6822 show indications that indeed the observed morphological hierarchy of young stellar clustering on pc and kpc scales reflects that of the turbulent ISM. I will discuss these findings and present our latest results from the application of star-counts on the exceptionally rich stellar sample achieved with the HST Panchromatic Andromeda galaxy Treasury (PHAT) program.
Caption: The star-forming region NGC346/N66 in the Small Magellanic Cloud, in a combination of multiwavelength data from ESA’s XMM-Newton space-borne X-ray observatory (blue), NASA's Spitzer Space Telescope (red) and the European Southern Observatory's New Technology Telescope (green). The resolved young stellar content of such regions reveal the clustered nature of star formation through its products.
Collaborators:
R. Klessen, ITA, Germany
S. Schmeja, ARI, Germany
PHAT Collaboration, PI J. Dalcanton, UW, USA
Key publication