L-subshell ionization of Ce, Nd, and Lu by 4-10-MeV C ions
- Department of Physics, East Carolina University, Greenville, North Carolina 27858 (United States)
- Department of Physics, University of Burdwan, Burdwan 713104 (India)
- Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India)
- Institute of Nuclear Research of the Hungarian Academy of Sciences (ATOMKI) H-4001, Debrecen, Pf. 51 (Hungary)
- Institute fuer Theoretische Physik, Universitaet Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland)
Ll,L{alpha},L{beta},L{gamma},L{gamma}{sub 1+5},L{gamma}{sub 2+3},L{gamma}{sub 4+4=} {sup '} x-ray production cross sections of {sub 58}Ce, {sub 60}Nd and {sub 71}Lu induced by 4-, 6-, 8-, and 10-MeV carbon ions were measured. For Lu, L{gamma}{sub 2+3} is separated from L{gamma}{sub 2+3+6} after revision of the technique of Datz et al. so that L{gamma}{sub 1+5} was used instead of L{gamma}{sub 1}, the L{gamma}{sub 4+4{sup '}}/L{gamma}{sub 1+5} ratio was corrected for multiple ionization, and uncertainties in L{gamma}{sub 4+4{sup '}} were incorporated in the fitting process. L-subshell ionization cross sections were extracted as a weighted average from two combinations of these cross sections, {l_brace}L{alpha},L{gamma}{sub 1+5},L{gamma}{sub 2+3}{r_brace} and {l_brace}L{alpha},L{gamma}{sub 1+5},L{gamma}{r_brace}. It is shown that, to within a few percent, the first of these two combinations results in the identical cross sections as this weighted average. Within 10%, permutations of different sets of single-hole atomic parameters yielded the same ionization cross sections. These cross sections are typically within 15% and at most 35% of the cross sections obtained with atomic parameters that were altered in two different ways for multiple ionization. Extracted subshell and total L-shell ionization cross sections as well as Ce and Nd data of Braziewicz et al. are compared with the ECPSSR theory of Brandt and Lapicki that accounts for the energy-loss (E), Coulomb-deflection (C), perturbed-stationary-state (PSS) and relativistic (R) effects. These measurements are also compared with the ECPSSR theory after its corrections--in a separated and united atom (USA) treatment, and for the intrashell (IS) transitions with the factors of Sarkadi and Mukoyama normalized to match L-shell cross section with the sum of L-subshell cross sections--as well as with the similarly improved semiclassical approximation of Trautmann. For Ce and Nd, the agreement of the extracted ionization cross sections with these theories is poor for L{sub 1} and good for L{sub 2}, L{sub 3}, and total L shell ionization. For the L{sub 2} subshell, this agreement is better for Ce and Nd than for Lu. The ECPSSR theory corrected for the USA and IS effects is surprisingly good for the L{sub 1}-subshell ionization of Lu, while at 4 MeV a similarly corrected semiclassical approximation is in excellent agreement with L{sub 2} and L{sub 3} data but overestimates the L{sub 1} measurement by almost a factor of 2.
- OSTI ID:
- 20718149
- Journal Information:
- Physical Review. A, Vol. 72, Issue 2; Other Information: DOI: 10.1103/PhysRevA.72.022729; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1050-2947
- Country of Publication:
- United States
- Language:
- English
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