The early dynamical evolution of cool, clumpy star clusters
| Autor: | Simon P. Goodwin, Richard J. Parker, Simon Portegies Zwart, Richard de Grijs, Richard J. Allison |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
Physics
010308 nuclear & particles physics Astronomy and Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics Escape velocity Astrophysics 01 natural sciences Stars Star cluster Space and Planetary Science 0103 physical sciences Cluster (physics) Astrophysics::Solar and Stellar Astrophysics Halo 010303 astronomy & astrophysics Astrophysics::Galaxy Astrophysics Dense core |
| Zdroj: | Monthly Notices of the Royal Astronomical Society. 407:1098-1107 |
| ISSN: | 0035-8711 |
| DOI: | 10.1111/j.1365-2966.2010.16939.x |
| Popis: | Observations and theory both suggest that star clusters form sub-virial (cool) with highly sub-structured distributions. We perform a large ensemble of N-body simulations of moderate-sized (N=1000) cool, fractal clusters to investigate their early dynamical evolution. We find that cool, clumpy clusters dynamically mass segregate on a short timescale, that Trapezium-like massive higher-order multiples are commonly formed, and that massive stars are often ejected from clusters with velocities > 10 km/s (c.f. the average escape velocity of 2.5 km/s). The properties of clusters also change rapidly on very short timescales. Young clusters may also undergo core collapse events, in which a dense core containing massive stars is hardened due to energy losses to a halo of lower-mass stars. Such events can blow young clusters apart with no need for gas expulsion. The warmer and less substructured a cluster is initially, the less extreme its evolution. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text