High-resolution projectile Auger spectroscopy for Li, Be, B and C excited in single gas collisions. I. Line energies for prompt decays

Energy levels, Auger branching ratios, and radiative rates of the core-excited states of B-like carbon

Energy levels, Auger branching ratios, and radiative rates of the core-excited states of B-like carbon are calculated by the saddle-point variation and saddle-point complex-rotation methods. Relativistic and mass polarization corrections are included using first-order perturbation theory. Calculated Auger channel energies and branching ratios are used to identify high-resolution Auger spectrum in the 300-keV C(+) → CH(4) collision experiment. It is found that Auger decay of these five-electron core-excited states gives significant contributions to Auger spectrum in the range of 238-280 eV.

Metastable bound (1,3)D(o) states below N=3 ionization threshold of He+

The applicability of Ritz-variational principle for 3dnf ((1,3)D(o)) states lying between N=2 and N=3 ionization threshold of singly ionized helium is discussed in this communication. Probable existence of such a state for O(6+) within the planetary atmosphere in the polar regions of Jupiter is discussed.

Photoexcitation of He- hollow-ion resonances: observation of the 2s2p2 4P state

Highly correlated states are studied in He-, a fundamental 3-electron system and prototypical negative ion. The 2s2p(2) 4P state is observed for the first time. This state is detected in a resonant simultaneous double-Auger decay of unprecedented strength. In addition, the first measurements of photodetachment cross sections, positions, widths, and shapes of triply excited resonances in He- are reported. These measurements provide a sensitive test for several sophisticated ab initio calculations, and indicate differences in the position and shape of some structures.

Fock space multireference coupled cluster calculations based on an underlying bivariational self-consistent field on Auger and shape resonances

The Fock space multireference coupled cluster based on an underlying bivariational self-consistent field is applied to the problem of computing complex energy associated with Auger and shape resonances in e-atom scattering. It is concluded that the Fock space multireference coupled cluster based on a bivariational self-consistent field provides a useful and practical approach to calculation of resonance parameters. Numerical results are presented for the 2P shape resonance of Mg and Auger 1 s(-1) hole of Be.

Angle-resolved photoelectron spectrometry studies of the autoionization of the 2s(2)2p 2P triply excited state of atomic lithium: experimental results and R-matrix calculations

We have measured the angle-resolved energy dependence of the electrons emitted over the energy range of the triply excited 2s(2)2p 2P lithium resonance using synchrotron radiation. We have also calculated the behavior of the angular distribution parameter beta using the R-matrix approximation. Experimental and theoretical results are in good agreement and show deep minima in the 1s2p (1, 3)P ionic channels. The energy at which the minima occur does not coincide with the resonance energy, but is shifted towards higher energy.