Excitation-autoionization cross sections and rate coefficients of Cu-like ions
- Racah Institute of Physics, The Hebrew University, 91904 Jerusalem (Israel)
- Nuclear Research Center---Negev, P.O. Box 9001, 84190 Beer Sheva (Israel)
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States)
Detailed level-by-level calculations of the excitation-autoionization (EA) cross sections and rate coefficients were performed using the relativistic distorted-wave method along the Cu isoelectronic sequence for all the elements with 34{le}{ital Z}{le}92. While in a previous work only the 3{ital d}-4{ital l} inner-shell collisional excitations had been taken into account, the present extensive calculations include the 3{ital d}{sup 10}4{ital s}-3{ital d}{sup 9}4{ital snl} ({ital n}=4{endash}7 and {ital l}=0{endash}{ital n}{minus}1) and the 3{ital p}{sup 6}3{ital d}{sup 10}4{ital s}-3{ital p}{sup 5}3{ital d}{sup 10}4{ital snl} ({ital n}=4,5 and {ital l}=0{endash}{ital n}{minus}1) excitations. An extrapolation method is used to evaluate the contribution for higher principal quantum numbers. Configuration mixing and secondary autoionization processes following radiative decay from autoionizing levels are also included. The results show that the EA processes give a dominant contribution compared to direct ionization, up to a factor of about 15 at {ital Z}=43. The additional inner-shell excitations for {ital Z}{lt}55 produce an increase in the EA effect varying from 20{percent} to a factor of 2, with respect to the previously predicted 3{ital d}-4{ital l} EA rates. The additional excitations are the most significant for heavy elements with {ital Z}{approx_gt}55, since they open EA channels, resulting in an EA rate varying typically along the sequence from 3 to 1 times the direct ionization rate. {copyright} {ital 1996 The American Physical Society.}
- OSTI ID:
- 283846
- Journal Information:
- Physical Review A, Journal Name: Physical Review A Journal Issue: 5 Vol. 53; ISSN 1050-2947; ISSN PLRAAN
- Country of Publication:
- United States
- Language:
- English
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