Nucleosynthesis in FG Sge

We have obtained a series of high-quality spectra of FG Sge since before its dramatic 1992 August decline in brightness. These declines are very similar to those seen in R CrB stars. The results of our abundance analysis (using model atmospheres with a solar He/H ratio) indicate that the carbon abundance is currently greater than that determined by Langer et al, who first reported on the dramatic increase in the abundances of the rare-earth elements in FG Sge. We derive higher relative abundances of the rare-earths ([Me/Fe] similar to 3) than either Langer et al or Kipper and Kipper, which we attribute to some enhancement of these elements since similar to 1970. The pattern of relative heavy element abundances is consistent with a single neutron exposure near 0.3 mbarn(-1). We confirm previous claims that the relative scandium abundance is high ([Sc/Fe] similar to 1) in FG Sge and suggest that it is the result of neutron captures by the light elements leading up to Sc-45.