Calculation of the triple-to-double ionization cross-section ratio of Li in the sudden approximation at high energies

The triple-to-double ionization cross-section ratio of Li in the high-energ y limit was computed in the sudden approximation with relativistic wave fun ctions. Together with the calculated value of Dalgarno and Sadeghpour ( Phy s. Rev. A, 46 (1992) R3591), for the Li double-to-single ionization cross-s ection ratio, the value of 6.263 x 10(-5) was obtained for the triple-to-si ngle ionization cross-section ratio. This value is in full agreement with W ehlitz et al. experimental value of ( 6.38 +/- 2.40) x 10(-5) obtained rece ntly with synchrotron radiation ( Phys. Rev. Lett., 81 (1998) 1813).