title: Agreement of Experiment and Theory on the Single Ionization of Helium by Fast Proton Impact.
abstract: Even though the study of ion-atom collisions is a mature field of atomic physics, large discrepancies between experiment and theoretical calculations are still common. Here we present experimental results with high momentum resolution on the single ionization of helium induced by 1-MeV protons, and we compare these to theoretical calculations. The overall agreement is strikingly good, and even the first Born approximation yields good agreement between theory and experiment. This has been expected for several decades, but so far has not been accomplished. The influence of projectile coherence effects on the measured data is briefly discussed in terms of an ongoing dispute on the existence of nodal structures in the electron angular emission distributions.
authors.affiliation: Institut für Kernphysik, Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Gassert
authors.affiliation: Joint Institute for Nuclear Research, Dubna, Moscow region 141980, Russia.|Institute of Mathematics, National University of Mongolia, 210646 Ulaanbaatar, Mongolia.
authors.forename: O
authors.initials: O
authors.lastname: Chuluunbaatar
authors.affiliation: Institut für Kernphysik, Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Waitz
authors.affiliation: Institut für Kernphysik, Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Trinter
authors.affiliation: Institut für Kernphysik, Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
authors.forename: H-K
authors.initials: HK
authors.lastname: Kim
authors.affiliation: Institut für Kernphysik, Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Bauer
authors.affiliation: Institut für Kernphysik, Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Laucke
authors.affiliation: Institut für Kernphysik, Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
authors.forename: Ch
authors.initials: Ch
authors.lastname: Müller
authors.affiliation: Institut für Kernphysik, Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Voigtsberger
authors.affiliation: Institut für Kernphysik, Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Weller
authors.affiliation: Institut für Kernphysik, Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Rist
authors.affiliation: Institut für Kernphysik, Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Pitzer
authors.affiliation: Institut für Kernphysik, Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Zeller
authors.affiliation: Institut für Kernphysik, Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Jahnke
authors.affiliation: Institut für Kernphysik, Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
authors.forename: L Ph H
authors.initials: LP
authors.lastname: Schmidt
authors.affiliation: Department of Physics, University of Nevada, Reno, Nevada 89557, USA.
authors.forename: J B
authors.initials: JB
authors.lastname: Williams
authors.affiliation: Department of Physics, Pacific State University, Tikhookeanskaya 136, Khabarovsk 680035, Russia.
authors.forename: S A
authors.initials: SA
authors.lastname: Zaytsev
authors.affiliation: Joint Institute for Nuclear Research, Dubna, Moscow region 141980, Russia.
authors.forename: A A
authors.initials: AA
authors.lastname: Bulychev
authors.affiliation: Faculty of Physics, Lomonosov Moscow State University, Moscow 119991, Russia.
authors.forename: K A
authors.initials: KA
authors.lastname: Kouzakov
authors.affiliation: Institut für Kernphysik, Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Schmidt-Böcking
authors.affiliation: Institut für Kernphysik, Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Dörner
authors.affiliation: Joint Institute for Nuclear Research, Dubna, Moscow region 141980, Russia.|Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow 119991, Russia.
authors.forename: Yu V
authors.initials: YV
authors.lastname: Popov
authors.affiliation: Institut für Kernphysik, Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt, Germany.
authors.forename: M S
authors.initials: MS
authors.lastname: Schöffler