8 papers
Structural Diversity Among the Milky Way's Dwarf Spheroidal Satellites
Matthew G. Walker, Raphaël Errani, Andrew B. Pace +3
We fit a flexible double power-law (`') model to the stellar density fields observed for the Milky Way's known dwarf spheroidal satellite galaxies. We show that where stand…
Collisional Dynamics of Stars and Dark Matter in Ultra-Faint Galaxies
Raphaël Errani, Raphaël Errani, Nicolas Esser +3
We use controlled N-body simulations to study the collisional exchange of energy between stars and dark matter in ultra-faint galaxies. We find that dynamical friction between star…
Stellar Cores Live Long and Prosper in Cuspy Dark Matter Halos
Jenni Häkkinen, Alexander Rawlings, Till Sawala +1
The existence of cuspy or cored centers of dark matter halos is a crucial discriminant between different dark matter models. It has recently been claimed based on dynamical argumen…
Tailored mass estimators for Milky Way dwarf Spheroidals
Sofia L. Splawska, Raphaël Errani, Jorge Peñarrubia +1
Assuming spherical symmetry and dynamical equilibrium within a given gravitational potential, a dwarf spheroidal (dSph) galaxy's globally averaged stellar velocity dispersion depen…
Signatures of dark subhalos in dwarf spheroidal galaxies: I. Fluctuations in surface density
Eduardo Vitral, Jorge Peñarrubia, Matthew G. Walker
Dark matter (DM) subhalos offer critical tests of cosmological models through their abundance and properties, yet most remain undetectable due to their lack of stars. We investigat…
Stellar Mass Segregation in Dark Matter Halos
Raphaël Errani, Jorge Peñarrubia, Matthew G. Walker
We study the effect of stellar mass segregation driven by collisional relaxation within the potential well of a smooth dark matter halo. This effect is of particular relevance for…