The ultra heavy nuclei of the galactic cosmic radiation

Abstract

Solid state nuclear track detectors have played a major role in the study of the charge and energy spectra of cosmic radiation. This is particularly so in the case of the elements in the upper regions of the periodic table where, up to 1979, the only data available was obtained by use of nuclear emulsions and plastic track detectors. Recent electronic experiments aboard earth orbiting satellites have provided new measurements of the charge spectra of these very rare nuclei. Because of their very small abundances in our galaxy (and apparently in the cosmic radiation also) further large scale experiments will be necessary to determine the charge spectrum accurately. High charge resolution will be required and recent developments indicate that nuclear track detectors are once again on the threshold of making a major contribution to this field.