is also enhanced in the latter, and remnants can reach luminosities and velocity dispersions as low as those of Ultra Faint Dwarfs (UFDs) In two cases a merger transforms the objects quickly into a spheroidal system already before infall. We argue that cuspy progenitors must be the exception rather than the rule among satellites of the MW since all the MW and M31 satellites in the luminosity range of our remnants are dSphs, a result matched only in the simulation with “cored” models. This suggests an early and efficient transformation of cusps into cores for Local Group satellites.'
author:
- 'Mihai Tomozeiu, Lucio Mayer'
- Thomas Quinn
bibliography:
- 'ads.bib'
title: ' The evolution of dwarf galaxy satellites with different dark matter density profiles in the ErisMod simulations. I. The early infalls'
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Introduction
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Dwarf galaxy satellites of the Milky Way (MW) and M31 are the main focus of “near-field cosmology”, providing a plethora of useful constraints and tests for galaxy formation theories as well as for the nature of dark matter in the $\Lambda$CDM paradigm. Yet their origin is still not completely understood. Nearly all the known satellites, located within the expected virial radius of the bright spirals, 