Rapid Quasirelativistic and Relativistic Calculations of Atomic Data for Plasma Modeling
Final technical rept. 15 Sep 1888-14 Sep 1990
PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF ASTRONOMY
Pagination or Media Count:
A rapid, yet accurate, approach for relativistic atomic structure and relativistic distorted wave exciatation of highly charged ions has been developed and the corresponding computer programs written. These have been applied to large scale calculations of collision strengths and oscillator strengths for Neon-like, Lithium-like, Sodium-like, Copper-like, Fluorine-like and Nickel-like ions. In performing the latter two sets of calculations the atomic structure program was expanded to include the generalized Breit interaction together with other QED corrections. Very recently a version of the collision strength program that includes the generalized Briet interaction in calculating the scattering matrix elements has also been obtained. The effect of this has been found to be quite significant for many transitions involving excitation from the 1s shell in H-like, He-like and Li-like ions with z or 50. It has been shown that distorted wave ionization cross sections can generally be expressed in the convenient form of a summation of the product of a readily calculated quantity that depends only on ion properties and a cross section having exactly the same form as a hydrogenic ionization cross section except that the radial functions are calculated using the appropriate potential for the actual ion being considered. Illustrative numerical results for ionization have been obtained and it appears that fits convenient for plasma modeling applications can be made. Versions of both the excitation and ionization programs that calculate excitation or ionization to specific final magnetic sublevels have been obtained. This is of interest for interpreting some EBIT experiments and some solar flare observations.
- Atomic and Molecular Physics and Spectroscopy