Orateur
Prof.
Wyn Evans
(IOA, Cambridge University)
Description
The recent years have seen an abundance of discoveries of substructure
in the haloes of the Milky Way and Andromeda galaxies. These have been
driven by availability of high quality multi-band photometric data.
The "missing satellite" problem has been transformed with the doubling
of the number of known Milky Way dwarf galaxies in the last few
years. The number density of satellite galaxies continues to rise
towards low luminosities, but may flatten at or below an absolute
magnitude of -5. There is now rough agreement with theories of galaxy
formation in CDM cosmologies, although the detailed luminosity function
eludes prediction.
There have also been discoveries of many new tidal streams from dwarf
galaxies and globular clusters, including the Orphan Stream and the
GD-1 stream. These can be used to delineate the size and shape of the
dark matter halo of the Galaxy, the rotation curve of the Galaxy, as
well as to constrain the abundance of dark matter substructure.
Detailed luminosity profiles of the largest stellar stream, the
Sagittarius stream, allow us to reassemble its progenitor, which is
comparable to the present-day Small Magellanic Cloud in brightness and
dark matter content.
Implications of the panoply of discoveries for the dark matter
distribution in the Milky Way as well as direct and indirect detection
experiments for dark matter will be discussed.
Author
Prof.
Wyn Evans
(IOA, Cambridge University)
