A KMOS survey of the nuclear disk of the Milky Way I: Survey design and metallicities

Understand

In the central few degrees of the bulge of the Milky Way there is a flattened structure of gas, dust and stars (the central molecular zone) similar to nuclear disks in other galaxies.

• Due to extreme foreground extinction we possess only sparse information about the (mostly old) stellar population of the nuclear disc.
• Here we present our KMOS spectroscopic survey of the stars in the nuclear disk reaching the old populations.
• In order to obtain an unbiased data set, we sample stars in the full extinction range along each line-of-sight.