Super Star Clusters Versus OB Associations

Weidner, Carsten; Bonnell, Ian A.; Zinnecker, Hans
Referencia bibliográfica

The Astrophysical Journal, Volume 724, Issue 2, pp. 1503-1508 (2010).

Fecha de publicación:
12
2010
Número de autores
3
Número de autores del IAC
0
Número de citas
40
Número de citas referidas
36
Descripción
Super star clusters (M ecl > 105 M sun) are the largest stellar nurseries in our local Universe, containing hundreds of thousands to millions of young stars within a few light years. Many of these systems are found in external galaxies, especially in pairs of interacting galaxies, and in some dwarf galaxies, but relatively few in disk galaxies like our own Milky Way. We show that a possible explanation for this difference is the presence of shear in normal spiral galaxies which impedes the formation of the very large and dense super star clusters but prefers the formation of loose OB associations possibly with a less massive cluster at the center. In contrast, in interacting galaxies and in dwarf galaxies, regions can collapse without having a large-scale sense of rotation. This lack of rotational support allows the giant clouds of gas and stars to concentrate into a single, dense, and gravitationally bound system.