Mass assembly history and infall time of the Fornax dwarf spheroidal galaxy

Understand

We use cosmological simulations to identify dark matter subhalo host candidates of the Fornax dwarf spheroidal galaxy using the stellar kinematic properties of Fornax.

• We consider cold dark matter (CDM), warm dark matter (WDM), and decaying dark matter (DDM) simulations for our models of structure formation.
• The subhalo candidates in CDM typically have smaller mass and higher concentrations at z = 0 than the corresponding candidates in WDM and DDM.
• We examine the formation histories of the ~ 100 Fornax candidate subhalos identified in CDM simulations and, using approximate luminosity-mass relationships for subhalos, we find two of these subhalos that are consistent with both the Fornax luminosity and kinematics.