Chemodynamical Modelling of the Galactic Bulge and Bar
  We present the first self-consistent chemodynamical model fitted to reproduce
data for the galactic bulge, bar and inner disk. We extend the Made-to-Measure
method to an augmented phase-space including the metallicity of stars, and show
its first application to the bar region of the Milky Way. Using data from the
ARGOS and APOGEE (DR12) surveys, we adapt the recent dynamical model from
Portail et al. to reproduce the observed spatial and kinematic variations as a
function of metallicity, thus allowing the detailed study of the 3D density
distributions, kinematics and orbital structure of stars in different
metallicity bins. We find that metal-rich stars with [Fe/H] > -0.5 are strongly
barred and have dynamical properties that are consistent with a common disk
origin. Metal-poor stars with [Fe/H] < -0.5 show strong kinematic variations
with metallicity, indicating varying contributions from the underlying stellar
populations. Outside the central kpc, metal-poor stars are found to have the
density and kinematics of a thick disk while in the inner kpc, evidence for an
extra concentration of metal-poor stars is found. Finally, the combined orbit
distributions of all metallicities in the model naturally reproduce the
observed vertex deviations in the bulge. This paper demonstrates the power of
Made-to-Measure chemodynamical models, that when extended to other chemical
dimensions will be very powerful tools to maximize the information obtained
from large spectroscopic surveys such as APOGEE, GALAH and MOONS.
