Electron-impact-excitation cross sections of hydrogenlike ions

Abstract

We present cross sections for electron-impact-induced transitions n → n ′ in hydrogen-like ions C 5+ , N e 9+ , Al 12+ , and Ar 17+ . The cross sections are computed by Coulomb-Born with exchange and normalization (CBE) method for all transitions with n < n ′ < 7 and by convergent closecoupling (CCC) method for transitions with n < n ′ < 5 in C 5+ and Al 12+ . Cross sections 1s → 2s and 1s → 2p are presented as well. The CCC and CBE cross sections agree to better than 10% with each other and with earlier close-coupling results (available for transition 1 → 2 only). Analytical expression for n → n ′ cross sections and semiempirical formulae are discussed. PACS number(s): 34.80.Kw

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