Early evolution and three-dimensional structure of embedded star clusters

ABSTRACT We perform simulations of star cluster formation to investigate the morphological evolution embedded clusters in earliest stages their evolution. conduct our with Torch, which uses Amuse framework couple state-of-the-art stellar dynamics formation, radiation, winds, and hydrodynamics Flash. simulate a suite 104 M⊙ clouds at 0.0683 pc resolution for ∼2 Myr after onset virial parameters α = 0.8, 2.0, 4.0 different random samplings initial mass function prescriptions primordial binaries. Our result population realistic morphologies (sizes, densities, ellipticities) that reproduce known trend higher having lower efficiencies. key results are as follows: (1) Cluster growth is not monotonic, can lose up half while they embedded. (2) morphology correlated changes over ∼0.01 time-scales. (3) The an indicative its long-term but only recent history: radius ellipticity increase sharply when accretes stars. (4) dynamical very young masses ≲1000 dominated by overall gravitational potential star-forming region rather than internal processes such two- or few-body relaxation.