Far Ultraviolet Spectroscopic Explorer Measurements of Interstellar Fluorine

The source of fluorine is not well understood, although core-collapse supernovae, Wolf-Rayet stars, and asymptotic giant branch stars have been suggested. A search for evidence of the -process during Type II supernovae is presented. Absorption from interstellar F i is seen in spectra of HD 208440 and HD 209339A acquired with the Far Ultraviolet Spectroscopic Explorer. In order to extract the column density for F i from the line at 954 8, absorption from H2 has to be modeled and then removed. Our analysis indicates that for H2 column densities less than about 3 ; 10 cm , the amount of F i can be determined from k954. For these two sight lines, there is no clear indication for enhanced F abundances resulting from the -process in a region shaped by past supernovae. Subject headinggs: ISM: abundances — ISM: atoms — nuclear reactions, nucleosynthesis, abundances — stars: individual (HD 208440, HD 209339A)