Quantifying the strength and asymmetry of giant resonances in the photorecombination ofSc3+and the photoionization ofSc2+

Abstract

We report on strong interference effects for the dominant, highly correlated, broad, and asymmetric 3p 5 3d 2 ( 2 F o 5/2,7/2 ) giant resonances in the photorecombination of Sc 3+ . Using a nonorthogonal perturbative multiconfiguration Breit-Pauli approach, we present theoretical photorecombination cross sections that are in line with the Test Storage Ring measurements of Schippers et al. In order to reproduce the observed asymmetric resonance profiles near threshold, it was necessary to include resonance-continuum interference. Also, we present Sc 2+ photoionization cross sections that agree with the Advance Light Source measurements of Schippers et al. This perturbative method is based on analytical expressions for the cross sections in terms of computed energies and transition rates, thereby directly determining resonance strengths and Fano asymmetry parameters. Of particular note, our reported absolute cross sections are in excellent agreement with experimental results, in contrast to all previous theoretical calculations. Furthermore, the apparent violation of the sum rule prediction, determined both from our integrated photoionization cross sections and from experimental results, is found to be due to radiative damping of narrow resonances.

Potential barrier effects in high-order harmonic generation by transition-metal ions

“…The calculation of these photoionization cross sections with proper account of many-electron interactions presents a considerable technical challenge even at the present time. [20].) In Fig.…”

Dielectronic recombination of argon-like ions

“…2 have been analyzed more fully in our earlier studies of Sc iv (Nikolić et al 2010) and Ti v (Nikolić et al 2009), but the following points should be made. First, there is experimental data available for both of these ions (Schippers et al 1998(Schippers et al , 2002, and these measurements were useful for quantifying the positions of low-energy resonances.…”

“…Details about the full optimization procedure are reported earlier by Nikolić et al (2009). adopted from: (a) Nikolić et al (2010); (b) Nikolić et al (2009). and conveniently modeled using physically-motivated fitting formulae (Burgess 1965)…”

“…The present computational study is part of an ongoing investigation of DR processes in argon-like ions (Nikolić et al 2007(Nikolić et al , 2009(Nikolić et al , 2010, and deals with Δn c = 0, 1 ionic core excitations and associated dielectronic resonances that dominate electron-ion recombination in photoionized plasmas. The theoretical foundation and computational method we use for the DR calculations are found elsewhere (Badnell et al 2003) and here we only outline the essence.…”

Vortices and vortex states in Rashba spin-orbit-coupled condensates

“…This happens when the number of condensed particles per vortex becomes small. Quantum melting of Abrikosov lattices has been argued to yield fractional quantum Hall liquids [84][85][86][87][88][89][90] . It is entirely possible by analogy that quantum melting of the type-I vortex lattice would also produce a fractional quantum liquid.…”