The cross sections for the production of 99 different target fragments from reactions of 8.0 GeV ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ with ${}_{}{}^{181}{}_{}{}^{}\mathrm{Ta}$ and ${}_{}{}^{197}{}_{}{}^{}\mathrm{Au}$ were measured. The target fragment radioactivities were measured by off-line gamma-ray spectroscopy. Details of the measurement as well as the calculation of the independent isotopic production cross sections and the integrated mass yields are given. Comparisons of these data to previously reported data for proton induced reactions show that the target residue production cross sections scale with the total projectile kinetic energy, not velocity. The total cross section for residue production indicates that some products result from collisions with significant overlap of the central densities of the two nuclei, in contrast to results obtained with low mass targets. Comparisons of the data with a Monte Carlo cascade calculation and an abrasion-ablation calculation verify the importance of ground state correlations of the neutrons and protons on the fragmentation isotopic cross sections.

NUCLEAR REACTIONS ${}_{}{}^{181}{}_{}{}^{}\mathrm{Ta}$(${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$, spallation), ${}_{}{}^{197}{}_{}{}^{}\mathrm{Au}$ (${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$, spallation), $E=8.0\mathrm{}$ GeV; measured radionuclide production cross sections and isobaric yields; comparison to proton induced spallation of ${}_{}{}^{181}{}_{}{}^{}\mathrm{Ta}$ and ${}_{}{}^{197}{}_{}{}^{}\mathrm{Au}$; comparison to abrasion-ablation and Monte Carlo cascade models for residue production; Ge(Li) spectroscopy, radioanalytical mass and charge distributions; relativistic heavy ion nuclear reactions.

• Received 14 June 1979

DOI:https://doi.org/10.1103/PhysRevC.21.1783