R-matrix calculation of antiproton capture by helium ions

Journal Article · Mon Oct 15 04:00:00 EDT 2007 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.76.042513· OSTI ID:21020719

Sakimoto, Kazuhiro ^[1]

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

Rigorous treatment is presented for antiproton capture by helium ions, i.e., p+He{sup +}{yields}(pHe{sup +}){sup **}{yields}pHe{sup 2+}+e, by using R-matrix theory. The present work applies the R-matrix method to an exotic collision system containing an antiproton, a nucleus, and an electron. The eigenvalue problem in the R-matrix method is solved by the discrete-variable-representation algorithm without use of any decoupling approximation. The probability of antiproton capture is calculated for the total angular momentum J=30. A huge number of the overlapping resonances are found to be prominent everywhere over a wide range of energies. As suggested in a time-dependent wave-packet propagation calculation [K. Sakimoto, Phys. Rev. A 74, 022709 (2006)], the resonances make a dominant contribution to the antiproton capture. It is found that the nonadiabatic coupling is always weak in off-resonance collisions, but can be very strong in resonance collisions.

• OSTI ID: 21020719
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 4 Vol. 76; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ANGULAR MOMENTUM
ANTIPROTONS
APPROXIMATIONS
ATOM-ATOM COLLISIONS
CAPTURE
CATIONS
COUPLING
EIGENFUNCTIONS
EIGENVALUES
ELECTRON-ATOM COLLISIONS
ELECTRONS
EXCITATION
HADRONIC ATOMS
HELIUM IONS
METASTABLE STATES
R MATRIX
TIME DEPENDENCE
WAVE PACKETS
WAVE PROPAGATION