Electron-impact ionization of neon at 100 eV: a benchmark comparison between experiment and theory for a complex target*

As a fundamental test for state-of-the-art theoretical approaches, we have studied the single ionization $(2p)$ of neon at a projectile energy of 100~eV. The experimental data were acquired using an advanced reaction microscope that benefits from a high efficiency and a large solid-angle acceptance of almost $4\pi$ [1]. We put special emphasis on the ability to measure inter\-normalized triple-differential cross-sections over a large part of the phase space. The data are compared to predictions from a second-order hybrid distorted-wave plus $R$-matrix model and a fully non\-perturbative $B$-spline $R$-matrix with pseudo-states approach [2]. For a target of this complexity and the low-energy regime, unprecedented agreement between experiment and the BSR model is found. This represents a significant step forward in the investigation of (e,2e) processes involving complex targets.\\[4pt] [1] J. Ullrich, R. Moshammer, A. Dorn, R. D\"orner, L. Schmidt, and H. Schmidt-B\"ocking, Rep. Prog. Phys. {\bf 66} (2003) 1463.\\[0pt] [2] O. Zatsarinny and K. Bartschat, Phys. Rev. A {\bf 86} (2012) 022717.