Experimental test of the superheavy fission hypothesis in acid residues from the allende meteorite

A description of a series of experiments to find evidence to confirm or contradict the hypothesis that isotopically anomalous Xe (called CCF-Xe) in carbonaceous chondrite meteorites results from the fission decay of a superheavy element is given. The first two experiments were searches for fossil evidence - fission tracks and isotopic anomalies - of superheavy fission decay in the Allende carbonaceous chondrite. It was demonstrated that chromite, a mineral rich in CCF-Xe, records fission tracks, and a search for such tracks in Allende chromite was performed with negative results. It was also demonstrated in certain CCF-XE rich phases of Allende, isotopic anomalies like those seen in Xe should be detectable in Ba and the light rare earths. Preliminary results from a collaborative measurement (with the University of Paris) show the Ba isotopic ratios to be normal in a CCF-Xe rich Allende sample. The third experiment was motivated by reports of the detection of a live, fissioning superheavy element, using a neutron counting technique, in bulk Allende (Flerov, 1978). Since almost all of the allegedly fissiogenic Xe in Allende is concentrated in certain acid insoluble phases, we developed a technique to detect low-level fission activity in these phases. Allende acid insoluble residue (provided by the University of Chicago) was dispersed in a 1 mg/cm2 layer, between two track recording detectors. An automatic track locating system was developed to allow large detector areas to be scanned for rate fission events