Measurement of the ratio of double-to-single photoionization of helium at 2. 8 keV using synchrotron radiation

Journal Article · Mon Aug 19 04:00:00 EDT 1991 · Physical Review Letters; (United States)

DOI:https://doi.org/10.1103/PhysRevLett.67.968· OSTI ID:5312751

Levin, J C; Lindle, D W; Keller, N; Miller, R D; Azuma, Y; Mansour, N B; Berry, H G; Sellin, I A ^[1]

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1. Department of Physics, University of Tennessee, Knoxville, Tennessee (USA) Oak Ridge National Laboratory, Oak Ridge, Tennessee (USA) National Institute of Standards and Technology, Gaithersburg, Maryland (USA) Physics Division, Argonne National Laboratory, Argonne, Illinois (USA)

We report the first measurement of the ratio of double-to-single photoionization of helium well above the double-ionization threshold. Using a time-of-flight technique, we find He{sup ++}/He{sup +}=1.6{plus minus}0.3% at {ital h}{nu}=2.8 keV. This value lies between calculations by Amusia (2.3%) and by Samson, who predicts 1.2% by analogy with electron-impact ionization cross sections of singly charged ions. Good agreement is obtained with older shake calculations of Byron and Joachain, and of Aberg, who predict 1.7%.

• DOE Contract Number: AC05-84OR21400; W-31109-ENG-38; AC02-76CH00016
• OSTI ID: 5312751
• Journal Information: Physical Review Letters; (United States), Journal Name: Physical Review Letters; (United States) Vol. 67:8; ISSN PRLTA; ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

640302* -- Atomic
Molecular & Chemical Physics-- Atomic & Molecular Properties & Theory
74 ATOMIC AND MOLECULAR PHYSICS
CHARGE STATE
CORRELATIONS
CROSS SECTIONS
DATA
ELECTROMAGNETIC RADIATION
ELEMENTS
ENERGY
ENERGY RANGE
EV RANGE
EV RANGE 100-1000
EXPERIMENTAL DATA
FLUIDS
GASES
HELIUM
INFORMATION
IONIZATION
IONIZING RADIATIONS
KEV RANGE
KEV RANGE 01-10
NONMETALS
NUMERICAL DATA
PHOTOIONIZATION
RADIATIONS
RARE GASES
THRESHOLD ENERGY
TIME-OF-FLIGHT METHOD
X RADIATION