Effect of the Initial Density and Angular-Velocity Profiles of Pre-stellar Cores on the Properties of Young Stellar Objects
- Author(s)
- Eduard Vorobyov
- Abstract
The physical properties of young stellar objects are studied as functions of the initial spatial distributions of the gas surface density and angular velocity in pre-stellar cores using numerical hydrodynamic simulations. Two limiting cases are considered: spatially homogeneous cores with Omega=const and Sigma = const and centrally concentrated cores with radius-dependent densities ~ 1/r and Omega ~ 1/r. The degree of gravitational instability and protostellar disk fragmentation is mostly determined by the initial core mass and the ratio of the rotational to the gravitational energy, and depends only weakly on the initial spatial configuration of pre-stellar cores, except for the earliest stages of evolution, when models with spatially homogeneous cores can be more gravitationally unstable. The accretion of disk matter onto a protostar also depends weakly on the initial distributions of Omega and Sigma, with matter from the collapsing core falling onto the disk at a rate that is slightly higher in models with spatially homogeneous cores. An appreciable dependence of the disk mass, disk radius, and the disk-to-protostar mass ratio on the initial density and angular velocity profiles of the parent core is found only for class 0 young objects; this relationship is not systematic in the later I and II stages of stellar evolution. The mass of the central
protostar depends weakly on the initial core configuration in all three evolutionary stages.
- Organisation(s)
- Department of Astrophysics
- Journal
- Astronomy Reports
- Volume
- 56
- Pages
- 179-192
- No. of pages
- 14
- ISSN
- 1063-7729
- DOI
- https://doi.org/10.1134/S1063772912020102
- Publication date
- 2012
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103004 Astrophysics
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/956f2d7b-5998-4a0f-8f44-c19583a1aee9