Conference paper Open Access

The Dynamics of OB Associations

Wright, Nicholas J.

Editor(s)
Scott Wolk

The formation and evolution of young star clusters and OB associations is fundamental to our understanding of the star formation process, the conditions faced by young binary and planetary systems, and the formation of long-lived open and globular clusters. Despite this our understanding of the physical processes that drive this evolution has been limited by the static nature of most observations. This is all changing thanks to a revolution in kinematic data quality from large-scale radial velocity surveys and new astrometric facilities such as {\it Gaia}. Here I summarise recent studies of multiple OB associations from both {\it Gaia} and ground-based astrometric surveys. These observations show that OB associations have considerable kinematic substructure and no evidence for the radial expansion pattern predicted by theories such as residual gas expulsion. This means that, contrary to the standard view of OB associations as expanded star clusters, these systems could never have been dense star clusters in the past and were most likely born as extended and highly substructured groups of stars. This places strong constraints on the primordial clustering of young stars and the conditions faced by young planetary systems.

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  • Allison, R. J., Goodwin, S. P., Parker, R. J., Portegies Zwart, S. F., de Grijs, R., et al. 2009, MNRAS, 395, 1449.

  • Ambartsumian, V. A. 1947, Stellar Evolution and Astrophysics (Armenian Acad. of Sci.).

  • Ambartsumian, V. A. 1949, Dokl. Akad. Nauk SSR, 68.

  • Armstrong, J. J., Wright, N. J., & Jeffries, R. D. 2018, MNRAS, 480, L121.

  • Baumgardt, H. & Kroupa, P. 2007, MNRAS, 380, 1589.

  • Blaauw, A. 1952, BAIN, 11, 414.

  • Blaauw, A. 1964, ARA&A, 2, 213.

  • Bonnell, I. A., Bate, M. R., Clarke, C. J., & Pringle, J. E. 2001, MNRAS, 323, 785.

  • Briceño, C., Preibisch, T., Sherry, W. H., Mamajek, E. A., Mathieu, R. D., et al. 2007, In Protostars and Planets V, edited by B. Reipurth, D. Jewitt, & K. Keil, pp. 345–360.

  • Brown, A. G. A., Blaauw, A., Hoogerwerf, R., de Bruijne, J. H. J., & de Zeeuw, P. T. 1999, In NATO Advanced Sci- ence Institutes (ASI) Series C, edited by C. J. Lada & N. D. Kylafis, vol. 540, p. 411.

  • Brown, A. G. A., Dekker, G., & de Zeeuw, P. T. 1997, MNRAS, 285, 479.

  • Cartwright, A. & Whitworth, A. P. 2004, MNRAS, 348, 589.

  • Chen, C. H., Mamajek, E. E., Bitner, M. A., Pecaut, M., Su, K. Y. L., et al. 2011, ApJ, 738, 122.

  • Dahm, S. E., Slesnick, C. L., & White, R. J. 2012, ApJ, 745, 56.

  • de Zeeuw, P. T., Hoogerwerf, R., de Bruijne, J. H. J., Brown, A. G. A., & Blaauw, A. 1999, AJ, 117, 354.

  • Dobbs, C. L. & Pringle, J. E. 2013, MNRAS, 432, 653.

  • Drew, J. E., Greimel, R., Irwin, M. J., & Sale, S. E. 2008, MN- RAS, 386, 1761.

  • Gaia Collaboration, Brown, A. G. A., Vallenari, A., Prusti, T., de Bruijne, J. H. J., et al. 2016a, A&A, 595, A2.

  • Gaia Collaboration, Prusti, T., de Bruijne, J. H. J., Brown, A. G. A., Vallenari, A., et al. 2016b, A&A, 595, A1.

  • Geary, R. C. 1954, The Incorporated Statistician, 5, 115.

  • Gontcharov, G. A. 2006, Astronomy Letters, 32, 759.

  • Griffiths, D. W., Goodwin, S. P., & Caballero-Nieves, S. M. 2018, MNRAS, 476, 2493.

  • Hills, J. G. 1980, ApJ, 235, 986.

  • Kharchenko, N. V., Scholz, R.-D., Piskunov, A. E., Röser, S., & Schilbach, E. 2007, Astronomische Nachrichten, 328, 889.

  • Kiminki, D. C., Kobulnicky, H. A., Kinemuchi, K., Irwin, J. S., Fryer, C. L., et al. 2007, ApJ, 664, 1102.

  • Kruijssen, J. M. D. 2011, In Stellar Clusters and Associations: A RIA Workshop on Gaia, pp. 137–141.

  • Lada, C. J. & Lada, E. A. 2003, ARA&A, 41, 57.

  • Lada, C. J., Margulis, M., & Dearborn, D. 1984, ApJ, 285, 141.

  • Mamajek, E. E. & Bell, C. P. M. 2014, MNRAS, 445, 2169.

  • Mamajek, E. E., Meyer, M. R., & Liebert, J. 2002, AJ, 124, 1670.

  • Maschberger, T. & Clarke, C. J. 2011, MNRAS, 416, 541.

  • Moran, P. A. P. 1950, Biometrika, 37, 17.

  • Parker, R. J. & Wright, N. J. 2016, MNRAS, 457, 3430.

  • Parker, R. J., Wright, N. J., Goodwin, S. P., & Meyer, M. R. 2014, MNRAS, 438, 620.

  • Pecaut, M. J. & Mamajek, E. E. 2016, MNRAS, 461, 794.

  • Pfalzner, S. 2009, A&A, 498, L37.

  • Preibisch, T. & Mamajek, E. 2008, The Nearest OB Associa- tion: Scorpius-Centaurus (Sco OB2), p. 235 (Handbook of Star Forming Regions).

  • Rizzuto, A. C., Ireland, M. J., & Robertson, J. G. 2011, MNRAS, 416, 3108.

  • Rygl, K. L. J., Brunthaler, A., Sanna, A., Menten, K. M., Reid, M. J., et al. 2012, A&A, 539, A79.

  • Weidner, C. & Kroupa, P. 2006, MNRAS, 365, 1333.

  • Wright, N. J., Bouy, H., Drew, J. E., Sarro, L. M., Bertin, E., et al. 2016, MNRAS, 460, 2593.

  • Wright, N. J. & Drake, J. J. 2009, ApJS, 184, 84.

  • Wright, N. J., Drake, J. J., Drew, J. E., & Vink, J. S. 2010, ApJ, 713, 871.

  • Wright, N. J., Drake, J. J., Guarcello, M. G., Aldcroft, T. L., Kashyap, V. L., et al. 2014a, ArXiv e-prints 1408.6579.

  • Wright, N. J., Drew, J. E., & Mohr-Smith, M. 2015, MNRAS, 449, 741.

  • Wright, N. J. & Mamajek, E. E. 2018, MNRAS, 476, 381.

  • Wright, N. J., Parker, R. J., Goodwin, S. P., & Drake, J. J. 2014b, MNRAS, 438, 639.

  • Yorke, H. W. & Sonnhalter, C. 2002, ApJ, 569, 846.

  • Zinnecker, H. & Yorke, H. W. 2007, ARA&A, 45, 481.

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