Relative multiple ionization cross sections of neon by projectiles in the 1-2-MeV/amu energy range

The change in the Kα x-ray spectra of neon is studied as a function of projectiles of C+3,+4,+5,+6, N+4,+6,+7, O+4,+5,+6,+7,+8, and F⁺⁹ having an energy between 1 and 2 MeV/amu. The spectra are observed using a curved crystal spectrometer. Combined with previous measurements data are obtained for projectiles from carbon to argon. X rays are observed from different ionization states of Ne designated by KLⁿ for n=1-7. An 81% correction between the KL⁵ peak and KL⁶ peak is derived. Semiempirical fluorescence yields are applied to the relative x-ray intensities to obtain relative multiple ionization cross sections. These cross sections are fitted by a binomial distribution as predicted by Coulomb ionization. All cases give good fits except for the F⁺⁹ induced spectra. A possible explanation is that a different excitation mechanism may exist for this near-symmetric collision case.