The Persistent Correlation Eeects in Double Ionization of Helium{like Atoms or Ions Which Are Probed with High Energy Photons Typeset Using Revt E X 2
نویسنده
چکیده
We analyze the correlation eeects in two electron atoms and ions which can be probed in double ionization with high energy photons. We consider total cross sections and diierential cross sections for double ionization by pho-toabsorption and Compton scattering and discuss the shake and non{shake mechanisms which may contribute to these observables. The total cross section for photoabsorption (at high energies) is determined by two mechanisms, the shake{oo mechanism and a quasi{equal{energy sharing mechanism, while for Compton scattering it is determined by the shake{oo mechanism. In general the shake{oo mechanism probes diierent distances in the two processes, so that the shake{oo ratios are diierent. Analyzing diierential cross sections , we are able to distinguish the shake from the non{shake contributions in photoabsorption, or the variation of shake{oo result with distance probed in Compton scattering. We discuss the utilization of the double ionization Compton proole (as distinguished from the ordinary Compton proole) for 1 studying the correlation eeects in Helium.
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