
%0 Journal Article
%A Gribakin, G. F. 
%A Gribakina, A. A. 
%A Flambaum, V. V. 
%T Quantum Chaos in Multicharged Ions and Statistical Approach to the Calculation of Electron&#8211;Ion Resonant Radiative Recombination
%J Australian Journal of Physics
%D 1999/07/15
%V 52
%N 3
%P 443-457
%K 
%R https://doi.org/10.1071/PH98093
%U https://www.publish.csiro.au/paper/PH98093 
%X We show that the spectrum and eigenstates of open-shell multicharged atomic ions near the ionisation threshold are chaotic, as a result of extremely high level densities of multiply excited electron states (103 eV&#8211;1 in Au24+) and strong configuration mixing. This complexity enables one to use statistical methods to analyse the system. We examine the dependence of the orbital occupation numbers and single-particle energies on the excitation energy of the system, and show that the occupation numbers are described by the Fermi&#8211;Dirac distribution, and the temperature and chemical potential can be introduced. The Fermi&#8211;Dirac temperature is close to the temperature defined through the canonical distribution. Using a statistical approach we estimate the contribution of multielectron resonant states to the radiative capture of low-energy electrons by Au25+ and demonstrate that this mechanism fully accounts for the 102 times enhancement of the recombination over the direct radiative recombination, in agreement with recent experimental observations. 
