Analysis of the results of calibrating meteoritic olivine crystals with²³⁸U nuclei at the Bevalac accelerator

The results are presented of calibrating the sensitivity of olivine crystals from meteorites by the U-238 nuclei produced at the Bevalac accelerator. The comparative studies of the spectra of the etchable track lengths due to the U-238 nuclei and to "fossil" tracks in these olivines have shown that the group of the 210-mu-m "fossil" tracks observed in 1980 at the LNR, JINR is due to the galactic cosmic-ray nuclei of the Th-U group. As regards the origin of the 340-360-mu-m group of "fossil" tracks which were considered in [2] to be candidates for superheavy nuclei in cosmic rays the presence of the track with a length of up to 360-mu-m in the calibrating U-2388 track length spectra indicates that the above interpretation has to be questioned. The possible ways of the unambiguous identification of the group of the abnormally long "fossil" tracks are discussed.