Scaled electron ionization cross sections in the Born approximation for atoms with 55< or =Z< or =102

Journal Article · Wed Aug 01 04:00:00 EDT 1979 · Phys. Rev., A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.20.445· OSTI ID:6248316

McGuire, E J

Using the generalized oscillator-strength formulation of the Born approximation, the author calculated electron ionization cross sections for all significant subshells of every fourth atom with 58< or =Z< or =102, and for Hg. The calculations used approximate Herman-Skillman wave functions and eigenvalues. The cross sections were put in scaled form, depending essentially on ionization energy only. The scaled cross sections were used with experimental energies to calculate the cross sections for Cs, Cs/sup +/, Ba, Ba/sup +/, Au, Hg, Tl, Tl/sup +/, and Pb. The cross sections so calculated were in good agreement with the measurements. Both inner-shell ionization and excitation followed by autoionization were prominent contributors to the cross section. The scaling procedure was used to calculate the electron ionization cross section of the noble-gas metastable levels, and there is excellent agreement with measured values for Ne and A. The scaling procedure was used to calculate cross sections for the sequential ionization Ni/sup +1/--Ni/sup +14/ and Au/sup +3/--Au/sup +14/, which were compared with cross sections obtained from the semiempirical expression of Lotz. Good agreement was found for the Ni ions, but there was poor agreement for the Au ions. Lotz's expression is a factor of 3 smaller than our scaled cross section for the 4d, 4f, and 5d subshells. It is suggested that the absence of measurements on these subshells precluded correct parametrization in the semiempirical expression of Lotz.

• Research Organization: Sandia Laboratories, Albuquerque, New Mexico 87115
• OSTI ID: 6248316
• Journal Information: Phys. Rev., A; (United States), Journal Name: Phys. Rev., A; (United States) Vol. 20:2; ISSN PLRAA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular &amp; Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ALKALI METALS
ALKALINE EARTH METALS
ATOM COLLISIONS
ATOMIC IONS
BARIUM
BARIUM IONS
BORN APPROXIMATION
CESIUM
CESIUM IONS
CHARGED PARTICLES
COLLISIONS
CROSS SECTIONS
ELECTRON COLLISIONS
ELECTRON-ATOM COLLISIONS
ELECTRON-ION COLLISIONS
ELEMENTS
GOLD
ION COLLISIONS
IONIZATION
IONS
LEAD
MERCURY
METALS
THALLIUM
THALLIUM IONS
TRANSITION ELEMENTS
TRANSURANIUM ELEMENTS