Excitation cross section of the niobium atom

We have extended and further improved a recent R-matrix with pseudo-states calculation for electron-impact excitation of boron. Based on excellent agreement between experimental and theoretical structure results, new data for elastic scattering and electron-impact excitation from the (2s 2 2p) 2 P o ground state and the (2s2p 2 ) 4 P metastable excited state are presented for incident projectile energies between 0 and 3 Ryd, together with the total ionization cross section. Comparison of the results with those from previous R-matrix and distortedwave calculations illustrates the need for sophisticated treatments of both the discrete and the continuum target spectrum.

Section: Introductionsupporting

confidence: 55%

R-matrix with pseudo-states calculation for electron-impact excitation and ionization of boron

Marchalant

Bartschat

1997

“…Accurate cross section data for electron scattering from boron-like atoms and ions are of great practical importance, for example, for plasma diagnostics in astrophysics and thermonuclear fusion (see, for example, Itikawa et al 1984, Itikawa 1990. Experimental data for excitation cross sections of neutral boron were obtained by Kuchenev and Smirnov (1981) who applied the method of intersecting electron and atomic beams. However, a sophisticated R-matrix calculation for electron scattering from neutral boron by Nakazaki and Berrington (1991), who used the R-matrix code of Berrington et al (1978), indicated possible normalization problems in the absolute values given by Kuchenev and Smirnov (1981).…”

mentioning

confidence: 99%

“…Experimental data for excitation cross sections of neutral boron were obtained by Kuchenev and Smirnov (1981) who applied the method of intersecting electron and atomic beams. However, a sophisticated R-matrix calculation for electron scattering from neutral boron by Nakazaki and Berrington (1991), who used the R-matrix code of Berrington et al (1978), indicated possible normalization problems in the absolute values given by Kuchenev and Smirnov (1981). In addition to the R-matrix results, predictions from first-order distorted-wave calculations Clark 1992, Clark andAbdallah 1996) are also available in the literature.…”

mentioning

confidence: 99%

Electron-impact excitation of boron

Marchalant

Bartschat

Berrington

et al. 1997

Results from an R-matrix with pseudo-states (RMPS) calculation are presented for electron-impact excitation of the (2s 2 2p) 2 P o → (2s2p 2 ) 4 P, (2s 2 2p) 2 P o → (2s 2 3s) 2 S and (2s 2 2p) 2 P o → (2s2p 2 ) 2 D transitions in neutral boron for incident energies from threshold up to 3 Ryd. At energies above the ionization threshold (0.61 Ryd), the inclusion of target continuum states in the close-coupling expansion is found to be crucial for accurate results to be obtained. Compared to previous first-order distorted-wave and R-matrix calculations with only discrete states, the present work represents a significant improvement in the prediction of the total excitation cross sections in the above energy range.

“…Furthermore, as determined e.g. for calcium (Kuchenev and Smirnov 1995), aluminum (Kuchenev and Smirnov 1990), and xenon (Smirnov 2002a), there is a remarkable similarity of OEF shapes in unperturbed sections of series for transitions originating at levels with different n values. On the contrary, perturbations may cause OEFs to differ sharply.…”

Section: Resultsmentioning

confidence: 59%

Empirical regularities in the excitation cross-section behavior of the lead atom (transitions from energy levels of 6pndconfigurations)

Smirnov¹

2018

Electron-impact excitation of lead atom levels belonging to 6pnd configurations has been studied in experiment. One hundred two excitation cross-sections have been measured at an incident electron energy of 50 eV. Eleven optical excitation functions (OEFs) have been recorded in the exciting electron energy range of E=0-200 eV. The resulting findings were used to study the excitation cross-sections dependence on the principal quantum number of upper levels for thirteen PbI spectral series.