Differential double-excitation cross sections in 50--150-keV proton-helium collisions

Journal Article · Tue Feb 28 23:00:00 EST 1995 · Physical Review A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.51.2140· OSTI ID:6584817

Schulz, M; Htwe, W T; Gaus, A D; Peacher, J L; Vajnai, T ^[1]

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1. Department of Physics and the Laboratory for Atomic, Molecular, and Optical Research, University of Missouri-Rolla, Rolla, Missouri 65401 (United States)

We have measured projectile-energy-loss spectra for 50-, 100-, and 150-keV [ital p]+He collisions. From the data we obtained differential double-excitation cross sections as a function of projectile scattering angle. At 150 keV a pronounced peak structure was observed at about 0.7 mrad for double excitation to the (2[ital p][sup 2]) [sup 1][ital D] and (2[ital s]2[ital p]) [sup 1][ital P] states. Our data provide indications for the dominance of a first-order mechanism involving the electron-electron interaction in double excitation for 150 keV at small scattering angles. At lower projectile energies and larger scattering angles a second-order mechanism appears to be of the same order of magnitude as the first-order mechanism. In these regimes, interference effects between the first- and second-order mechanisms could be important.

• OSTI ID: 6584817
• Journal Information: Physical Review A; (United States), Journal Name: Physical Review A; (United States) Vol. 51:3; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

664300* -- Atomic & Molecular Physics-- Collision Phenomena-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ATOM COLLISIONS
BARYONS
COLLISIONS
CROSS SECTIONS
DIFFERENTIAL CROSS SECTIONS
ELECTRON-ELECTRON INTERACTIONS
ELEMENTARY PARTICLES
ELEMENTS
ENERGY LOSSES
ENERGY RANGE
ENERGY-LEVEL TRANSITIONS
EXCITATION
FERMIONS
FLUIDS
GASES
HADRONS
HELIUM
INELASTIC SCATTERING
INTERACTIONS
ION COLLISIONS
ION-ATOM COLLISIONS
KEV RANGE
KEV RANGE 10-100
LEPTON-LEPTON INTERACTIONS
LOSSES
MANY-BODY PROBLEM
NONMETALS
NUCLEONS
PARTICLE INTERACTIONS
PROJECTILES
PROTONS
RARE GASES
SCATTERING
TWO-BODY PROBLEM