Ne KAuger electron emission following high-energyNe9+andAr9+ion impact on Ne

The production of $\mathrm{Ne} K$ Auger electrons is investigated in fast heavy-ion—atom collisions with the use of gas target and ${\mathrm{Ne}}^{9+}$ and ${\mathrm{Ar}}^{9+}$ ions ranging in energy from 3 MeV/amu to about 15 MeV/amu. In particular, the projectile energy dependence of multiple $L$-shell ionization in Ne is compared to previous results from heavy-ion—atom collisions covering a projectile energy range from 1.2 MeV/amu to about 3 MeV/amu with atomic numbers varying between 8 and 18. The proposed linear relationship between the mean number of multiple ionized outer-shell electrons and the centroid energy of the corresponding Auger spectra is confirmed. The scaling behavior of the multiple ionization in Ne as a function of projectile energy and atomic number is investigated. It is found that the degree of multiple outer-shell ionization can be represented by a universal curve over a wide range of projectile energy and species.