How old is my star? Calibrating [C/N] Abundance Ratios Using Star Clusters to Determine Stellar Ages.

In astronomy, large-scale surveys have been a useful tool in investigating Galactic evolution, both kinematically and chemically, however reliable stellar ages for stars are elusive. High resolution spectroscopic surveys can provide chemical abundances of different elements in stellar populations of clusters. These abundances can later be used to further constraint stellar ages. In particular, elemental abundances of carbon and nitrogen can be used as age indicators in red giant stars. These elements are produced in the CNO-cycle in previous evolutionary phases and due to the first dredge-up, and other convective mixing, they are brought to the stars surfaces. This convective mixing is dependent on the mass of the star and hence is related to the age of the star, giving a relationship between [C/N] abundances and stellar ages. Using the Open Cluster Abundances and Mapping (OCCAM) survey, based on SDSS/APOGEE survey, to obtain stellar parameters and abundances, we were able to create a uniform empirical relationship between stellar ages and [C/N] using open star clusters. We will explore the [C/N] abundance ratio for the large OCCAM sample probing a wider range of age and metallicity than previous work to further constraint stellar ages. This work is supported by NSF AST-1715662.