511 research outputs found
Full two-electron calculations of antiproton collisions with molecular hydrogen
Total cross sections for single ionization and excitation of molecular
hydrogen by antiproton impact are presented over a wide range of impact energy
from 1 keV to 6.5 MeV. A nonpertubative time-dependent close-coupling method is
applied to fully treat the correlated dynamics of the electrons. Good agreement
is obtained between the present calculations and experimental measurements of
single-ionization cross sections at high energies, whereas some discrepancies
with the experiment are found around the maximum. The importance of the
molecular geometry and a full two-electron description is demonstrated. The
present findings provide benchmark results which might be useful for the
development of molecular models.Comment: 4 pages, 3 figure
Beam-Material Interaction
Th is paper is motivated by the growing importance of better understanding of
the phenomena and consequences of high- intensity energetic particle beam
interactions with accelerator, generic target , and detector components. It
reviews the principal physical processes of fast-particle interactions with
matter, effects in materials under irradiation, materials response, related to
component lifetime and performance, simulation techniques, and methods of
mitigating the impact of radiation on the components and envir onment in
challenging current and future applicationComment: 28 pages, contribution to the 2014 Joint International Accelerator
School: Beam Loss and Accelerator Protection, Newport Beach, CA, USA , 5-14
Nov 201
Convergent close-coupling approach to antiproton and proton collisions with atomic and molecular targets
A semi-classical single-centre convergent close-coupling method for describing antiproton collisions with atomic and molecular targets has been developed. Excitation and ionisation of noble-gas atoms, molecular hydrogen and water molecule by antiproton impact have been investigated. In addition, a semi-classical two-centre convergent close-coupling method has been developed to study collisions of protons with atomic hydrogen including electron capture into bound and continuum states of the projectile. Calculated cross sections are in good agreement with experimental data
Coordinate-space Faddeev-Hahn-type approach to three-body charge transfer reactions involving exotic particles
Low-energy muon-transfer cross sections and rates in collisions of muonic
atoms with hydrogen isotopes are calculated using a six-state close-coupling
approximation to coordinate-space Faddeev-Hahn-type equations. In the muonic
case satisfactory results are obtained for all hydrogen isotopes and the
experimentaly observed strong isotopic dependence of transfer rates is also
reproduced. A comparison with results of other theoretical and available
experimental works is presented. The present model also leads to good transfer
cross sections in the well-understood problem of antihydrogen formation in
antiproton-positronium collision.Comment: 18 pages REVTeX, accepted for publication in Phys. Rev.
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