Propagation of UH cosmic ray nuclei in a leaky box

A weighted slab approximation to a leaky box model has been developed to study the influence of various parameters and cross sections on the propagation of Z > 28 ultraheavy (UH) cosmic ray nuclei from the source to earth. This model starts with nuclei of a given charge and energy and then follows them as they lose energy, fragment and escape. It is possible to vary the path length distribution, the escape length and the energy dependent cross sections of all the nuclei generated during the propagation. By combining the results for different nuclei and energies it is possible to compare any assumed source abundance distribution with that predicted at earth. This paper specifically considers the effects introduced when the cross sections are adjusted to take account of radioactive decays in flight, and shows that they are generally rather minor. Some predictions are made as to which elements will provide the best discriminators between various assumed sources.