Three-body Interactions In Proton-helium Angular Scattering

H++He scattering at 0.5 MeV has been investigated using a coincidence technique that completely determines the three-body transverse momentum exchange in single ionization collisions. Three scattering regions could be distinctly recognized that are dominated by proton helium-nucleus, proton-electron, or electron helium-nucleus interactions. Calculations and the experimental data show that the coupling between the electronic and nuclear degrees of freedom is required to understand the dynamics for more than 97% of the ionizing collisions. © 1989 The American Physical Society

\u3ci\u3eCivil Society, Conflict and Violence\u3c/i\u3e

Editors: Wolfgang Dörner and Regina A. List Chapter 6, The Law, Security and Civil Society Freedoms, co-authored by Brett Kyle, UNO faculty member. This book looks at the role that civil society organizations play in dealing with conflict and violence. The authors argue that in most of the prevalent conceptualizations the conflict dimension of civil society is either downplayed or inadequately addressed. They contend that the ability to deal with conflict is at the heart of organized civil society; in the political process, one of civil society\u27s key functions is to express and mediate between different interests, thus contributing to political decision-making. The chapters draw on detailed, empirical data from the CIVICUS Civil Society Index - a unique comparative data-set drawn from 25 countries, which has not previously been made publicly available. It examines the different ways violence has been manifested in civil societies, the meaning of violent protest and the impact of security legislation that might hinder the mediating efforts of civil society. The book offers a sophisticated comparison between conflict and post-conflict countries and an analysis of the role of civil society in conflict resolution, reconciliation and transitional justice.https://digitalcommons.unomaha.edu/facultybooks/1307/thumbnail.jp

Transfer ionization and its sensitivity to the ground-state wave function

We present kinematically complete theoretical calculations and experiments for transfer ionization in H$^++$He collisions at 630 keV/u. Experiment and theory are compared on the most detailed level of fully differential cross sections in the momentum space. This allows us to unambiguously identify contributions from the shake-off and two-step-2 mechanisms of the reaction. It is shown that the simultaneous electron transfer and ionization is highly sensitive to the quality of a trial initial-state wave function

Recoil-Ion and Electron Momentum Spectroscopy: Reaction-Microscopes

Recoil-ion and electron momentum spectroscopy is a rapidly developing technique that allows one to measure the vector momenta of several ions and electrons resulting from atomic or molecular fragmentation. In a unique combination, large solid angles close to 4 and superior momentum resolutions around a few per cent of an atomic unit (a.u.) are typically reached in state-of-the art machines, so-called reaction-microscopes. Evolving from recoil-ion and cold target recoil-ion momentum spectroscopy (COLTRIMS), reaction-microscopes—the `bubble chambers of atomic physics'—mark the decisive step forward to investigate many-particle quantum-dynamics occurring when atomic and molecular systems or even surfaces and solids are exposed to time-dependent external electromagnetic fields. This paper concentrates on just these latest technical developments and on at least four new classes of fragmentation experiments that have emerged within about the last five years. First, multi-dimensional images in momentum space brought unprecedented information on the dynamics of single-photon induced fragmentation of fixed-in-space molecules and on their structure. Second, a break-through in the investigation of high-intensity short-pulse laser induced fragmentation of atoms and molecules has been achieved by using reaction-microscopes. Third, for electron and ion-impact, the investigation of two-electron reactions has matured to a state such that the first fully differential cross sections (FDCSs) are reported. Fourth, comprehensive sets of FDCSs for single ionization of atoms by ion-impact, the most basic atomic fragmentation reaction, brought new insight, a couple of surprises and unexpected challenges to theory at keV to GeV collision energies. In addition, a brief summary on the kinematics is provided at the beginning. Finally, the rich future potential of the method is briefly envisaged