Fluorine Abundances in Local Stellar Populations

The origin of the light, odd-Z element fluorine remains uncertain, though it is thought to be produced in multiple stellar sites such as asymptotic giant branch stars, rapidly rotating massive stars, Wolf-Rayet stars, the v-process in core-collapse supernovae, and novae. Several nucleosynthetic channels may contribute to the Galactic fluorine abundance, with different processes dominating certain stellar populations (such as thin-disk, thick-disk, and budge stars) and/or at certain metallicities. We determine the abundance of fluorine in local stellar populations from the (2-0) R9 2.3358 μm feature of the HF molecule for 11 normal K giants using spectra obtained with the Phoenix IR spectrometer on the 2.1-m telescope at Kitt Peak. The chemical abundances are analyzed in the context of Galactic chemical evolution to explore the contributions of different nucleosynthetic channels that have been suggested.