| Issue |
A&A
Volume 524, December 2010
|
|
|---|---|---|
| Article Number | A62 | |
| Number of page(s) | 9 | |
| Section | Galactic structure, stellar clusters and populations | |
| DOI | https://doi.org/10.1051/0004-6361/201014901 | |
| Published online | 23 November 2010 | |
Calibration of radii and masses of open clusters with a simulation
1
Astronomisches Rechen-Institut, Zentrum für Astronomie der
Universität Heidelberg, Mönchhofstrasse 12–14, 69120
Heidelberg,
Germany
e-mail: aernst@ari.uni-heidelberg.de
2
National Astronomical Observatories of China, Chinese Academy of
Sciences, Datun Lu 20A, Chaoyang
District, Beijing
100012, PR
China
3
Main Astronomical Observatory, National Academy of Sciences of
Ukraine, Akademika Zabolotnoho
27, 03680
Kyiv,
Ukraine
4
Institut für Astronomie der Universität Wien,
Türkenschanzstraße
17, 1180
Wien,
Austria
Received:
30
April
2010
Accepted:
1
September
2010
Context. Piskunov and collaborators developed a method to make a simple mass estimate for tidally limited star clusters based on the identification of the tidal radius in a King profile with the dynamical Jacobi radius. The application of this method to an unbiased open cluster catalog yielded significantly higher cluster masses than the classical methods.
Aims. We quantify the bias in the mass determination as a function of projection direction and cluster age by analyzing a simulated star cluster.
Methods. We use direct N-body simulations of a star cluster in an analytic Milky Way potential that account for stellar evolution and apply a best fit to the projected number density of cluster stars.
Results. We obtain significantly overestimated star cluster masses that depend strongly on the viewing direction. The overestimation is typically in the range of 10–50 percent and reaches a factor of 3.5 for young clusters. Mass segregation reduces the derived limiting radii systematically.
Key words: methods: statistical / methods: data analaysis / open clusters and associations: general / solar neighborhood
© ESO, 2010
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.