TheB-splineR-matrix method for atomic processes: application to atomic structure, electron collisions and photoionization

Abstract

The basic ideas of the B-spline R-matrix (BSR) approach are reviewed, and the use of the method is illustrated with a variety of applications to atomic structure, electron–atom collisions and photo-induced processes. Special emphasis is placed on complex, open-shell targets, for which the method has proven very successful in reproducing, for example, a wealth of near-threshold resonance structures. Recent extensions to a fully relativistic framework and intermediate energies have allowed for an accurate treatment of heavy targets as well as a fully nonperturbative scheme for electron-impact ionization. Finally, field-free BSR Hamiltonian and electric dipole matrices can be employed in the time-dependent treatment of intense short-pulse laser–atom interactions.

Electron collisions with atoms, ions, molecules, and surfaces: Fundamental science empowering advances in technology

“…The remaining discrepancies very close to threshold are most likely due to experimental issues, whereas theory apparently has some problems left for the 5s′[1/2] 1 state. Nevertheless, the unprecedented agreement between experiment and theory achieved in this study resolved discrepancies between previous measurements and calculations of angle-integrated cross sections for this collision system, as well as other heavy noble-gas targets (18). Fig.…”

LXCat: an Open‐Access, Web‐Based Platform for Data Needed for Modeling Low Temperature Plasmas

“…[32] An overview of the method and many examples of its application can be found in a recent review by Zatsarinny and Bartschat. [33] An important advantage of the method is its ability to employ individually optimized, term-dependent sets of nonorthogonal orbitals to account for the strong term dependence in the one-electron orbitals that is often found in complex targets. Furthermore, recent large-scale calculations, with a dense distribution of pseudostates to account for important coupling to the target continuum via the Rmatrix with pseudo-states (RMPS) approach, [34] have allowed for the ab initio calculation of ionization cross sections.…”

Free electron degeneracy effects on collisional excitation, ionization, de-excitation and three-body recombination

“…Experimentally, it is found that the differential crosssection is greater where one electron has more energy. The Mott differential 320 cross-section has been found to be a good fit to many experimental measurements [26], [27]. The Mott differential cross section can be written as follows [28] σ(E, E 1 ) = 4πa 2 0 R 2…”