Physical Review Letters
First page number:
Last page number:
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++/He+=1.6±0.3% at hν=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 Åberg, who predict 1.7%.
Helium; Photoionization of gases; Synchrotron radiation
Analytical Chemistry | Atomic, Molecular and Optical Physics | Biological and Chemical Physics | Elementary Particles and Fields and String Theory | Physical Chemistry
Copyright American Physical Society, used with permission
Levin, J. C.,
Lindle, D. W.,
Miller, R. D.,
Berrah Mansour, N.,
Berry, H. G.,
Sellin, I. A.
Measurement of the Ratio of Double-to-Single Photoionization of Helium at 2.8 keV Using Synchrotron Radiation.
Physical Review Letters, 67(8),
Analytical Chemistry Commons, Atomic, Molecular and Optical Physics Commons, Biological and Chemical Physics Commons, Elementary Particles and Fields and String Theory Commons, Physical Chemistry Commons