Wright, NJ, Parker, RJ, Goodwin, SP and Drake, JJ (2013) Dynamical evolution of star-forming regions. Monthly Notices of the Royal Astronomical Society, 438 (1). pp. 620-638. ISSN 1365-2966

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We model the dynamical evolution of star-forming regions with a wide range of initial properties. We follow the evolution of the regions’ substructure using the Q-parameter, we search for dynamical mass segregation using the ΛMSR technique, and we also quantify the evolution of local density around stars as a function of mass using the ΣLDR method. The amount of dynamical mass segregation measured by ΛMSR is generally only significant for subvirial and virialized, substructured regions – which usually evolve to form bound clusters. The ΣLDR method shows that massive stars attain higher local densities than the median value in all regions, even those that are supervirial and evolve to form (unbound) associations. We also introduce the Q−ΣLDR plot, which describes the evolution of spatial structure as a function of mass-weighted local density in a star-forming region. Initially dense (>1000 stars pc−2), bound regions always have Q>1,ΣLDR>2 after 5 Myr, whereas dense unbound regions always have Q<1,ΣLDR>2 after 5 Myr. Less dense regions (<100 stars pc−2) do not usually exhibit ΣLDR > 2 values, and if relatively high local density around massive stars arises purely from dynamics, then the Q−ΣLDR plot can be used to estimate the initial density of a star-forming region.

Item Type: Article
Additional Information: This article was accepted for publication in the Monthly Notices of the Royal Astronomical Society © 2013, published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
Uncontrolled Keywords: methods, numerical, stars, formation, open clusters and associations, general
Subjects: Q Science > QB Astronomy
Q Science > QC Physics
Divisions: Faculty of Natural Sciences > School of Physical and Geographical Sciences
Depositing User: Symplectic
Date Deposited: 12 Dec 2016 11:18
Last Modified: 23 May 2019 13:05
URI: https://eprints.keele.ac.uk/id/eprint/2619

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