The Dispersal of Young Stars and the Greater Sco-Cen Association

E. E. Mamajek; E. D. Feigelson

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arXiv · astro-ph/0105290

The Dispersal of Young Stars and the Greater Sco-Cen Association

E. E. Mamajek·E. D. Feigelson

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Abstract

We review topics related to the dispersal of young stars from their birth-sites, and focus in particular on the entourage of young stars related to the ongoing star-formation event in the Sco-Cen OB association. We conduct a follow-up kinematic study to that presented in Mamajek, Lawson, & Feigelson (2000; ApJ 544, 356) amongst nearby, isolated, young stars. In addition to the eta Cha and TW Hya groups, we find several more intriguing Sco-Cen outlier candidates: most notably beta Pic, PZ Tel, HD 199143, and HD 100546. We discuss the connection between Sco-Cen and the southern ``150 pc Conspiracy'' molecular clouds, and in particular, Corona Australis. The kinematic evidence suggests that many of the nearby, isolated ~10 Myr-old stars were born near Sco-Cen during the UCL and LCC starbursts 10-15 Myr ago. We hypothesize that these stars inherited 5-10 km/s velocities moving away from Sco-Cen, either through molecular cloud turbulence, or through formation in molecular clouds associated with the expanding Sco-Cen superbubbles (e.g. Loop I).

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BibTeX RIS

E. E. Mamajek, E. D. Feigelson. 2001-05-16. The Dispersal of Young Stars and the Greater Sco-Cen Association. https://arxiv.org/abs/astro-ph/0105290

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