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Full-Text Articles in Physics
Sub-Femtosecond Correlated Dynamics Explored With Antiprotons, J. Ullrich, A. Dorn, Daniel Fischer, R. Moshammer, B. Najjari, Michael Schulz, A. B. Voitkiv, C. P. Welsch
Sub-Femtosecond Correlated Dynamics Explored With Antiprotons, J. Ullrich, A. Dorn, Daniel Fischer, R. Moshammer, B. Najjari, Michael Schulz, A. B. Voitkiv, C. P. Welsch
Physics Faculty Research & Creative Works
Ionizing collisions of antiprotons with atoms or molecules at energies between a few keV up to about one MeV provide a unique tool to explore correlated dynamics of electrons at large perturbations on a time scale between several femtoseconds (1 fs = 10-15 s) down to some tens of attoseconds (1 as = 10-18 s). Exploiting and developing many-particle imaging methods - Reaction-Microscopes - integrated into a novel ultra-low energy storage ring (USR) for slow antiprotons will enable to access for the first time fully differential cross sections for single and multiple ionization in such collisions. Moreover, the …
Precollision And Postcollision Electron-Electron Correlation Effects For Intermediate-Energy Proton-Impact Ionization Of Helium, M. Foster, Jerry Peacher, Michael Schulz, Ahmad Hasan, Don H. Madison
Precollision And Postcollision Electron-Electron Correlation Effects For Intermediate-Energy Proton-Impact Ionization Of Helium, M. Foster, Jerry Peacher, Michael Schulz, Ahmad Hasan, Don H. Madison
Physics Faculty Research & Creative Works
We report fully differential cross sections (FDCS) for the single ionization of helium by a 75 keV incident energy proton. Previous three-body distorted wave (3DW) calculations for this collision system are in poor agreement with the absolute magnitude of the experimental measurements. The 3DW approximation treats the four-body problem as an effective three-body problem in which the passive electron does not participate in the collision. We have developed a full four-body approach in which the passive electron fully participates in the collision. It will be shown that the FDCS is very sensitive to the treatment of the passive electron-ejected electron …
Projectile-Residual-Target-Ion Scattering After Single Ionization Of Helium By Slow Proton Impact, N. V. Maydanyuk, Ahmad Hasan, M. Foster, B. Tooke, Don H. Madison, Michael Schulz, Emilio Nanni
Projectile-Residual-Target-Ion Scattering After Single Ionization Of Helium By Slow Proton Impact, N. V. Maydanyuk, Ahmad Hasan, M. Foster, B. Tooke, Don H. Madison, Michael Schulz, Emilio Nanni
Physics Faculty Research & Creative Works
We have measured fully differential single ionization cross sections for 75 keV p+He collisions. At this relatively small projectile velocity, signatures of the projectile-residual-target-ion interaction, which are not observable for fast projectiles and for electron impact, are revealed rather sensitively. In fact, this interaction appears to be more important than the postcollision interaction, which so far was assumed to be the most important factor in higher-order effects for slow ion impact. These features are not well reproduced by our three-distorted-wave calculations.