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 nu-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 Angstrom, absorption from H-2 has to be modeled and then removed. Our analysis indicates that for H-2 column densities less than about 3 x 10(20) cm(-2), the amount of F I can be determined from lambda954. For these two sight lines, there is no clear indication for enhanced F abundances resulting from the nu-process in a region shaped by past supernovae.