The creation, destruction, and transfer of multipole moments in electron- and proton-impact ionization of atoms and ions

• Published in: Journal of physics. B, Atomic, molecular, and optical physics Atomic, molecular, and optical physics, 2013-12, Vol.46 (24), p.1-12
• Main Authors: Csanak, G, Inal, M K, Fontes, C J, Kilcrease, D P
• Format: Article
• Language: English
• Subjects: Cross sections; Cross sections (physics); Destruction; Ionization; Multipoles; Plasmas; Symmetry; Wave propagation
• ISSN: 0953-4075; 1361-6455
• DOI: 10.1088/0953-4075146124/245202

Expanding on previous works that involved elastic and inelastic scattering of electrons by atoms and ions, we use the wave-packet propagation scheme of Dollard to define multipole moment creation, destruction and transfer cross sections for electron- and proton-impact ionization of atoms and ions. The electron-impact cross sections can then be used by defining appropriate rate coefficients for use in Fujimoto's population-alignment collisional-radiative model for cylindrically symmetric plasmas. Our result for the alignment creation cross section is in agreement with those formulae that were obtained earlier intuitively or by semi-classical collisional methods. The multipole cross sections obtained here can be used also for modelling the relaxation behaviour of laser-excited plasmas under cylindrical symmetry conditions. We have also derived the electron- and proton-impact ionization multipole cross sections in terms of Liouville-space quantities, which then enabled us by using group theoretical methods to obtain the azimuthal-angle dependence of the multipole cross sections and symmetry properties that are results of reflection across a plane over the collisional axis.