By the 1980s, CCF Xe actually being the product of fission was doubtful, and the alternate theory that it had arisen from r-process (neutron capture) nucleosynthesis gained more ground. Researchers looked at the isotopic anomalies in nearby elements samarium, neodymium, and barium, and compared to the amount of xenon. Whether CCF Xe was produced by nucleosynthesis or fission, comparable amounts of barium-135 should be produced. When researchers compared the experimental data to predicted amounts of Barium following each model, neither model came close to predicting the anomalies correctly, leading to Lewis et al. calling the experiment an "embarrassment" for both models. However, in the case of nucleosynthesis, it is possible that samarium, neodymium, and barium were separated from Xe by prior condensation in the supernova shell or plasma processes. Based on this data it was deemed unlikely that CCF Xe had actually arose from fission.