Program: GS-2017A-Q-62

The origin of fluorine is still unkown. Several sources are proposed for its production but until now there is observational evidence only in AGB stars. However, recent redeterminations of the F content in these stars has opened a discussion about the real contribution of AGB stars to the total F inventory and on the dependence of its production with the stellar metallicity. We will use high resolution spectroscopy to determine F abundances from HF lines in the K-band in a sample of Galactic SC-type carbon stars and extragalactic metal-poor AGB carbon stars to better evaluate the role of AGB stars in the evolution of the F abundance and the mechanism for its production in these stars.