4MOST Consortium Survey 4: Milky Way Disc and Bulge High-Resolution
  Survey (4MIDABLE-HR)
  The signatures of the formation and evolution of a galaxy are imprinted in
its stars. Their velocities, ages, and chemical compositions present major
constraints on models of galaxy formation, and on various processes such as the
gas inflows and outflows, the accretion of cold gas, radial migration, and the
variability of star formation activity. Understanding the evolution of the
Milky Way requires large observational datasets of stars via which these
quantities can be determined accurately. This is the science driver of the
4MOST MIlky way Disc And BuLgE High-Resolution (4MIDABLE-HR) survey: to obtain
high-resolution spectra at $R \sim 20\,000$ and to provide detailed elemental
abundances for large samples of stars in the Galactic disc and bulge. High data
quality will allow us to provide accurate spectroscopic diagnostics of two
million stellar spectra: precise radial velocities; rotation; abundances of
many elements, including those that are currently only accessible in the
optical, such as Li, s-, and r-process; and multi-epoch spectra for a
sub-sample of stars. Synergies with complementary missions like Gaia and TESS
will provide masses, stellar ages and multiplicity, forming a multi-dimensional
dataset that will allow us to explore and constrain the origin and structure of
the Milky Way.
