Abstract
In this paper we report a clustering analysis of upper main-sequence stars in the Small Magellanic Cloud, using data from the VMC survey (the VISTA near-infrared YJK s survey of the Magellanic system). Young stellar structures are identified as surface overdensities on a range of significance levels. They are found to be organized in a hierarchical pattern, such that larger structures at lower significance levels contain smaller ones at higher significance levels. They have very irregular morphologies, with a perimeter-area dimension of 1.44 ± 0.02 for their projected boundaries. They have a power-law mass-size relation, power-law size/mass distributions, and a log-normal surface density distribution. We derive a projected fractal dimension of 1.48 ± 0.03 from the mass-size relation, or of 1.4 ± 0.1 from the size distribution, reflecting significant lumpiness of the young stellar structures. These properties are remarkably similar to those of a turbulent interstellar medium, supporting a scenario of hierarchical star formation regulated by supersonic turbulence.
Original language | English |
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Article number | 31 |
Pages (from-to) | 1-15 |
Number of pages | 15 |
Journal | Astrophysical Journal |
Volume | 858 |
Issue number | 1 |
DOIs | |
Publication status | Published - 3 May 2018 |
Bibliographical note
Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.Keywords
- galaxies: star clusters: general
- infrared: stars
- Magellanic Clouds
- stars: formation