Effects of multiple ionization and intrashell coupling in L-subshell ionization by heavy ions
- Department of Physics, East Carolina University, Greenville, North Carolina 27858 (United States)
- Swami Jnanananda Laboratories for Nuclear Reasearch, Andhra University, Visakhapatnam-530 003 (India)
- Institute of Physics, Sachivalaya Marg, Bhubaneswar-751 005 (India)
L-subshell ionization cross sections are extracted from measured L{alpha}, L{beta}, L{gamma}, L{gamma}{sub 1}, L{gamma}{sub 23}, and L{gamma}{sub 44} x-ray production cross sections in thin targets of {sub 75}Re, {sub 78}Pt, and {sub 79}Au bombarded by 4-8 MeV C{sup 3+} ions. For each projectile energy, using the fluorescence and Coster-Kronig yields recently recommended by Campbell with an amendment for multiple ionization effects, a mutually consistent set of ionization cross sections is extracted from L{alpha} and six pairs of other L-line x-ray production cross sections. Extracted L{sub 1}-, L{sub 2}-, L{sub 3}-ionization cross sections are compared with the predictions of the ECPSSR theory--which accounts for the energy (E) loss and Coulomb (C) deflection of the projectile as well as for perturbed-stationary state (PSS) and relativistic (R) nature of L subshells--and its modification, ECUSAR-IS. In the ECUSAR-IS theory, the PSS effect is calculated with a united and separated atom (USA) treatment and the intrashell (IS) coupling is accounted for by multiplicative factors of Sarkadi and Mukoyama normalized so that the sum of L-subshell ECUSAR-IS cross sections equals ECUSAR L-shell ionization cross section without the IS correction. Further improvement of this theory to account for better wave functions in its evaluation is made by scaling it with ratios of Dirac-Hartree-Slater cross sections to the screened hydrogenic formulas used in the ECPSSR theory. Very good agreement is obtained with L{sub 2} and L{sub 3} ionization data. For the L{sub 1} subshell, the data are in good agreement with the ECPSSR theory but are by factors of 2 to 3 above the results of its modifications.
- OSTI ID:
- 20649949
- Journal Information:
- Physical Review. A, Vol. 70, Issue 6; Other Information: DOI: 10.1103/PhysRevA.70.062718; (c) 2004 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1050-2947
- Country of Publication:
- United States
- Language:
- English
Similar Records
[ital L]-subshell ionization cross sections in gold and bismuth by 3. 6--9. 5-MeV carbon and 4. 0--7. 2-MeV oxygen ions
Multiple ionization and coupling effects in L-subshell ionization of heavy atoms by oxygen ions