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arXiv · 1207.7071

The VLT-FLAMES Tarantula Survey VI: Evidence for rotation of the young massive cluster R136

V. Hénault-Brunet·M. Gieles·C. J. Evans·H. Sana·N. Bastian·J. Maíz Apellániz·W. D. Taylor·N. Markova·E. Bressert·A. de Koter·J. Th. van Loon
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Abstract

Although it has important ramifications for both the formation of star clusters and their subsequent dynamical evolution, rotation remains a largely unexplored characteristic of young star clusters (few Myr). Using multi-epoch spectroscopic data of the inner regions of 30 Doradus in the Large Magellanic Cloud (LMC) obtained as part of the VLT-FLAMES Tarantula Survey, we search for rotation of the young massive cluster R136. From the radial velocities of 36 apparently single O-type stars within a projected radius of 10 pc from the centre of the cluster, we find evidence, at the 95% confidence level, for rotation of the cluster as a whole. We use a maximum likelihood method to fit simple rotation curves to our data and find a typical rotational velocity of ~3 km/s. When compared to the low velocity dispersion of R136, our result suggests that star clusters may form with at least ~20% of the kinetic energy in rotation.

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V. Hénault-Brunet, M. Gieles, C. J. Evans, H. Sana, N. Bastian, J. Maíz Apellániz, W. D. Taylor, N. Markova, E. Bressert, A. de Koter, J. Th. van Loon. 2012-07-30. The VLT-FLAMES Tarantula Survey VI: Evidence for rotation of the young massive cluster R136. https://doi.org/10.1051/0004-6361%2F201219472

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