Generalizations of the R-Matrix Method to the Treatment of the Interaction of Short-Pulse Electromagnetic Radiation with Atoms

Since its initial development in the 1970s by Phil Burke and his collaborators, R-matrix theory associated computer codes have become method of choice for calculation accurate data general electron–atom/ion/molecule collision photoionization processes. The use a non-orthogonal set orbitals based on B-splines, now called B-spline (BSR) approach, was pioneered Zatsarinny. It has considerably extended flexibility approach improved particularly treatment complex many-electron atomic ionic targets, which are needed many modelling applications processes involving low-temperature plasmas. Both original BSR been to interaction short, intense electromagnetic (EM) radiation with atoms molecules. Here, we provide an overview theoretical tools that were required facilitate extension time domain. As example practical application, show results two-photon ionization argon short-pulse extreme ultraviolet radiation.