The galactic population of white dwarfs
  The contribution of white dwarfs of the different Galactic populations to the
stellar content of our Galaxy is only poorly known. Some authors claim a vast
population of halo white dwarfs, which would be in accordance with some
investigations of the early phases of Galaxy formation claiming a top-heavy
initial-mass-function. Here, I present a model of the population of white
dwarfs in the Milky Way based on observations of the local white dwarf sample
and a standard model of Galactic structure. This model will be used to estimate
the space densities of thin disc, thick disc and halo white dwarfs and their
contribution to the baryonic mass budget of the Milky Way. One result of this
investigation is that white dwarfs of the halo population contribute a large
fraction of the Galactic white dwarf number count, but they are not responsible
for the lion's share of stellar mass in the Milky Way. Another important result
is the substantial contribution of the - often neglected - population of thick
disc white dwarfs. Misclassification of thick disc white dwarfs is responsible
for overestimates of the halo population in previous investigations.
