Stopping Power of 1-9-MeV ${\mathrm{He}}^{++}$ Ions in U${\mathrm{O}}_2$, (U, Pu)${\mathrm{O}}_2$, and Th${\mathrm{O}}_2$

The stopping power and the range of ${\mathrm{He}}^{++}$ ions with energies between about 1 and 9 MeV have been measured for the oxides of nuclear interest U${\mathrm{O}}_2$, and (U, Pu)${\mathrm{O}}_2$, and Th${\mathrm{O}}_2$, using a new and versatile method. The experimental technique consisted in evaporating oxide layers onto a source emitting $\alpha$ particles of five different energies, and then determining $\frac{\mathrm{dE}}{\mathrm{dx}}$ by $\alpha$ spectroscopy. These multienergy sources could conveniently be obtained by exposing a metal foil to the recoil atoms of ${\mathrm{Th}}^{228}$, the radioactive decay chain of which contains five daughter nuclides with different $\alpha$ energies. In addition, the $\alpha$ spectra of thick homogeneous samples were also evaluated and yieldd confirmatory results. The data are compared to theoretical calculations. and their application in self-diffusion studies is discussed.