Action-based models for dwarf spheroidal galaxies and globular clusters
arXiv:1904.08447 · doi:10.1093/mnras/stz1617
Abstract
A new family of self-consistent DF-based models of stellar systems is explored. The stellar component of the models is described by a distribution function (DF) depending on the action integrals, previously used to model the Fornax dwarf spheroidal galaxy (dSph). The stellar component may cohabit with either a dark halo, also described by a DF, or with a massive central black hole. In all cases we solve for the model's self-consistent potential. Focussing on spherically symmetric models, we show how the stellar observables vary with the anisotropy prescribed by the DF, with the dominance and nature of the dark halo, and with the mass of the black hole. We show that precise fits to the observed surface brightness profiles of four globular clusters can be obtained for a wide range of prescribed velocity anisotropies. We also obtain precise fits to the observed projected densities of four dSphs. Finally, we present a three-component model of the Scupltor dSph with distinct DFs for the red and blue horizontal branch stars and the dark matter halo.
submitted to MNRAS
References in corpus (10)
- The Star Formation Histories of Local Group Dwarf Galaxies I. Hubble Space Telescope / Wide Field Planetary Camera 2 Observations
- The kinematic status and mass content of the Sculptor dwarf spheroidal galaxy
- Velocity Dispersion Profiles of Seven Dwarf Spheroidal Galaxies
- The stellar mass-halo mass relation of isolated field dwarfs: a critical test of CDM at the edge of galaxy formation
- Early flattening of dark matter cusps in dwarf spheroidal galaxies
- Action-based distribution functions for spheroidal galaxy components
- A centrally heated dark halo for our Galaxy
- Bringing the Galaxy's dark halo to life
- Made-to-Measure Dark Matter Haloes, Elliptical Galaxies and Dwarf Galaxies in Action Coordinates
- A low pre-infall mass for the Carina dwarf galaxy from disequilibrium modelling