Abstract
The threshold behavior of the single-photon double-ionization cross section of atomic oxygen has been studied using vacuum uv radiation from a synchrotron storage ring. The double-ionization cross section appears to follow a power law (where E is the kinetic energy of the two electrons) from its threshold to about 2.0 eV above with an exponent α=1.08±0.03, which is consistent with Wannier’s theoretical value of 1.056. The cross section also shows the influence of the doubly excited 2s2 (n,≳3) neutral states, among which the first three converge to the 2s2)4p) ionic state of oxygen.
- Received 11 August 1995
DOI:https://doi.org/10.1103/PhysRevA.52.4595
©1995 American Physical Society