Photoionization of doublet and quartet boron states as benchmarks for NewStock and ASTRA

Boron, a pervasive element in nature, is the simplest atom featuring three active electrons in the valence over an appreciably polarizable core. For these reasons, it is also an interesting system for benchmarking ab initio photoionization codes and their ability to investigate the effects of core-core, core-valence, and valence-valence correlation on observables characteristic of the electronic continuum such as the position and Auger decay rate of autoionizing states, photoionization cross-sections, and resonant asymmetry parameters. Here we present a comparison between calculations, for the doublet and quartet states of the boron atom, conducted with an ad-hoc high-precision three-active-electron code [1], with the results obtained with the NewStock atomic and the new ASTRA molecular polyelectronic ionization codes. In NewStock and ASTRA, resonance parameters are determined by diagonalizing the multi-channel close-coupling in the presence of exterior-complex scaling and complex absorbing boundaries, respectively.

[1] L. Argenti, R. Moccia, Phys. Rev. A 93, 042503 (2016).