Are hierarchically formed embedded star clusters surviving gas expulsion depending on their initial conditions?
Journal article, 2021

We investigate the dissolution process of young embedded star clusters with different primordial mass segregation levels using fractal distributions by means of N-body simulations. We combine several star clusters in virial and subvirial global states with Plummer and uniform density profiles to mimic the gas. The star clusters have masses of M-stars = 500 M-circle dot that follow an initial mass function where the stars have maximum distance from the centre of r = 1.5 pc. The clusters are placed in clouds that at the same radius have masses of M-cloud = 2000 M-circle dot, resulting in star formation efficiency of 0.2. We remove the background potential instantaneously at a very early phase, mimicking the most destructive scenario of gas expulsion. The evolution of the fraction of bound stellar mass is followed for a total of 16 Myr for simulations with stellar evolution and without. We compare our results with previous works using equal-mass particles where an analytical physical model was used to estimate the bound mass fraction after gas expulsion. We find that independent of the initial condition, the fraction of bound stellar mass can be well predicted just right after the gas expulsion but tends to be lower at later stages, as these systems evolve due to the stronger two-body interactions resulting from the inclusion of a realistic initial mass function. This discrepancy is independent of the primordial mass segregation level.

galaxies: star clusters: general

methods: numerical

galaxies: star formation

Author

R. Dominguez

Heidelberg University

Juan Pablo Farias Osses

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

M. Fellhauer

University of Concepcion

Ralf S. Klessen

Heidelberg University

Monthly Notices of the Royal Astronomical Society

0035-8711 (ISSN) 1365-2966 (eISSN)

Vol. 508 4 5410-5424

Subject Categories

Subatomic Physics

Meteorology and Atmospheric Sciences

Astronomy, Astrophysics and Cosmology

DOI

10.1093/mnras/stab2644

More information

Latest update

11/26/2021