Electron-impact excitation of the beryllium isoelectronic sequence

An analytic atomic independent-particle model potential adjusted to experimental energy levels is used to generate wave functions for the excited states of Bei, Bii, Ciii, Niv, and Ov. Using these wave functions in conjunction with the Born approximation and the $\mathrm{LS}$-coupling scheme, the authors calculate optical oscillator strengths, generalized oscillator strengths, and total cross sections for excitations from the $2s^2\left({}_{}{}^1{}_{}{}^{}S_0^{}{}_{}{}^{}\right)$ ground state. The results are compared with experimental ones and other calculations. Regularities and systematic trends along the isoelectronic sequence are discussed.