Electron degradation and yields of initial products. VII. Subexcitation electrons in gaseous and solid H sub 2 O

Journal Article · Sat Dec 01 04:00:00 EST 1990 · Physical Review, A; (USA)

DOI:https://doi.org/10.1103/PhysRevA.42.6486· OSTI ID:6097562

Ishii, M A; Kimura, M; Inokuti, M ^[1]

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1. Argonne National Laboratory, Argonne, IL (USA)

A comparative study of electron degradation spectra and yields for various species in gaseous and solid H{sub 2}O is carred out by using the rigorous Spencer-Fano theory and the continuous-slowing-down approximation (CSDA). As input we use cross-section data given by Hayashi (in {ital Atomic} {ital and} {ital Molecular} {ital Data} {ital for} {ital Radiotherapy}, Proceedings of an IAEA Advisory Group Meeting, Vienna, June 1988, Report No. IAEA-TECDOC-506 (International Atomic Energy Agency, Vienna, 1989), p. 193) for the gas and by Michaud and Sanche (Phys. Rev. 36, 4672 (1987)) for the solid. Vibrational excitation is the dominant mechanism of the slowing down of the electron in both gas and solid phases at intermediate energies of 8--2 eV. Rotational excitation for the gas and phonon excitation for the solid, which share the same origin of dynamics, are the second important mechanism. The general trends of the electron degradation spectra are similar in the two phases. However, details of the spectra differ notably from one another. Because the energy dependence of some of the cross sections is complex, the CSDA fails to reproduce even a local average of the Spencer-Fano degradation spectrum, and gives yields of various products appreciably different from those evaluated from the Spencer-Fano degradation spectrum.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 6097562
• Journal Information: Physical Review, A; (USA), Journal Name: Physical Review, A; (USA) Vol. 42:11; ISSN 1050-2947; ISSN PLRAA
• Country of Publication: United States
• Language: English

Related Subjects

654001* -- Radiation & Shielding Physics-- Radiation Physics
Shielding Calculations & Experiments
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
CHARGED-PARTICLE TRANSPORT
DATA ANALYSIS
ELECTRONS
ELEMENTARY PARTICLES
ENERGY LOSSES
ENERGY RANGE
EV RANGE
FERMIONS
FILMS
FLUIDS
GASES
ICE
LEPTONS
LOSSES
RADIATION TRANSPORT
REFLECTION
SLOWING-DOWN
SPENCER-FANO THEORY
THERMALIZATION
THIN FILMS
TRANSMISSION
VAPORS
WATER VAPOR