Experimental cross sections for electron-impact ionization of chromium ions: Cr/sup 6+/, Cr/sup 7+/, Cr/sup 8+/, and Cr/sup 10+/

Journal Article · Wed Mar 01 00:00:00 EST 1989 · Phys. Rev. A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.39.2397· OSTI ID:6207773

Sataka, M; Ohtani, S; Swenson, D; Gregory, D C

Absolute cross sections have been measured from below threshold to 1500 eV for electron-impact single ionization of chromium ions in initial charge states 6+, 7+, 8+, and 10+. The measurements utilized the Oak Ridge National Laboratory Electron Cyclotron Resonance ion source and electron-ion crossed-beams apparatus. The lowest three charge states, which have 3s/sup 2/3p/sup n/ ground-state electron configurations, all exhibit ionization onsets at lower energies than expected for ground-state ions, indicating the presence of ions in metastable configurations in the incident beams. Significant contributions to the total cross sections by excitation autoionization are observed for each ion. The present measurements are compared to calculations of direct ionization from the Lotz formula, and the Cr/sup 10+/ measurements are compared to previous data for the isoelectronic ion Ni/sup 14+/.

• Research Organization: Department of Physics, Japan Atomic Energy Research Institute, Tokai-mura, Ibaraki, 319-11 Japan
• OSTI ID: 6207773
• Journal Information: Phys. Rev. A; (United States), Vol. 39:5
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
CHROMIUM IONS
ELECTRON-ION COLLISIONS
EV RANGE 100-1000
EXPERIMENTAL DATA
IONIZATION
KEV RANGE 01-10
TOTAL CROSS SECTIONS
CHARGED PARTICLES
COLLISIONS
CROSS SECTIONS
DATA
ELECTRON COLLISIONS
ENERGY RANGE
EV RANGE
INFORMATION
ION COLLISIONS
IONS
KEV RANGE
NUMERICAL DATA
640304* - Atomic
Molecular & Chemical Physics- Collision Phenomena