An Upper Limit to the Age of the Galactic Bar

This is the authors' abstract. We don't add key points for this paper.

Using data from the Two Micron All Sky Survey, we identify a population of infrared carbon stars with J - K S ≥ 2 in the Milky Way. These stars are shown to trace the stellar bar previously identified in IR and optical surveys. The properties of C stars strongly suggest that they are of intermediate age. We conclude that the bar is likely to have formed more recently than 3 Gyr ago and must be younger than 6 Gyr. Implications and further tests of this conclusion are briefly discussed.