Electron scattering from krypton: High-resolution electron scattering experiments and B-spline R-matrix calculations

In a joint experimental and theoretical effort, we carried out a detailed study of elastic scattering and electron impact excitation of the $\rm 4p^5 5s$ states in Kr. We present independently normalized, absolute angle-differential cross sections over the entire angular range ($0^\circ - 180^\circ$) for a number of energies in the near-threshold region, as well as energy scans for selected angles. Interesting double minima were observed in the elastic cross section as a function of energy for backward angles. The present experimental results are in very satisfactory agreement with predictions from a fully relativistic Dirac \hbox{$B$-spline}\hbox{$R$-matrix} model~[1,2]. They clearly improve the agreement between experiment and theory relative to our earlier comparison [2] with the data of Phillips [3]. \\[4pt] [1] O. Zatsarinny and K. Bartschat, Phys. Rev. A {\bf 77} (2008) 062701.\\[0pt] [2] T. H. Hoffmann, M.-W. Ruf, H. Hotop, O. Zatsarinny, K. Bartschat, and M. Allan, J. Phys. B {\bf 43} (2010) 085206.\\[0pt] [3] J. M. Phillips, J. Phys. B {\bf 15} (1982) 4259.