Protonium formation in collinear collisions between antiprotons and hydrogen molecular ions: Quantum-classical hybrid method versus adiabatic approximation

Journal Article · Thu Apr 01 04:00:00 EST 2004 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.69.042710· OSTI ID:20640995

Sakimoto, Kazuhiro ^[1]

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1. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Yoshinodai, Sagamihara 229-8510 (Japan)

A quantum-classical hybrid (or semiclassical) method is applied to protonium formation p+H{sub 2}{sup +}{yields}pp+H and dissociation p+H{sub 2}{sup +}{yields}p+p+H at kinetic energies up to 200 eV. The electronic motion is accurately solved quantum mechanically, while the motion of the heavy particles p and p is described by classical mechanics. The p-p-p collinear configuration is assumed as a preliminary to three-dimensional calculations, and to assess the validity of the adiabatic approximation. Vibrational excitation to the dissociative continuum is crucial in pp formation in contrast to the importance of electron emission for the atomic-hydrogen target. For this reason, pp formation occurs efficiently even well beyond the ionization threshold if the target is a molecule.

• OSTI ID: 20640995
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 4 Vol. 69; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ADIABATIC APPROXIMATION
ANTIPROTON SOURCES
ANTIPROTONS
DISSOCIATION
ELECTRON EMISSION
EV RANGE
EXCITATION
HYBRIDIZATION
HYDROGEN
HYDROGEN IONS 2 PLUS
ION-MOLECULE COLLISIONS
IONIZATION
KINETIC ENERGY
MOLECULES
PROTONIUM
SEMICLASSICAL APPROXIMATION
THREE-DIMENSIONAL CALCULATIONS
VIBRATIONAL STATES