Ratio of double to single ionization of helium: The relationship between ionization by photons and by bare charged particles

Journal Article · Sun Jan 01 04:00:00 EST 1995 · Physical Review A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.51.400· OSTI ID:6692883

Manson, S T ^[1]; McGuire, J H ^[2]

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1. Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303 (United States)
2. Department of Physics, Tulane University, New Orleans, Louisiana 70118 (United States)

It is well known that cross sections for ionization of atoms by fast charged particles and by photons are related by the Bethe-Born theory. We employ this relationship to derive a corresponding relation for the ratio [ital R] of double to single ionization including the first two terms of the Bethe expansion. For sufficiently fast charged particles, where the second term can be ignored, the ratios as a function of [Delta][ital E]---the energies transferred to the atom by the projectile---for ionization by charged particles [ital R][sub [ital z]]([Delta][ital E]) and by photons [ital R][sub [gamma]]([Delta][ital E]) are equal: [ital R][sub [ital z]]([Delta][ital E])=[ital R][sub [gamma]]([Delta][ital E]). In addition, a relation for the ratio of total charged-particle impact ionization cross sections to the photon ratio is derived. The results are compared with recent experimental data and various discrepancies are found and discussed.

• OSTI ID: 6692883
• Journal Information: Physical Review A; (United States), Journal Name: Physical Review A; (United States) Vol. 51:1; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

664200* -- Spectra of Atoms & Molecules & their Interactions with Photons-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ATOM COLLISIONS
CHARGED PARTICLES
COLLISIONS
CONFIGURATION INTERACTION
CORRELATIONS
CROSS SECTIONS
ELECTRON CORRELATION
ELEMENTS
FLUIDS
GASES
HELIUM
IONIZATION
NONMETALS
PHOTOIONIZATION
PHOTON COLLISIONS
PHOTON-ATOM COLLISIONS
RARE GASES