Projectile Auger spectra of gas- and foil-excited oxygen ions at MeV energies

Bruch, R.; Schneider, D.; Schwarz, Winfried H.; Meinhart, M.; Johnson, B. M.; Taulbjerg, K

doi:10.1103/physreva.19.587

Cited by 63 publications

(51 citation statements)

References 37 publications

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“…A comparison of the calculations of the group of K.T. Chung (Lin et al 2001;Shiu et al 2001;Lin et al 2002) with the measurements of Bruch et al (1979Bruch et al ( , 1987 shows excellent agreement; the average difference between observed and calculated values is −0.05 ± 0.16 eV; we therefore adopt a nominal uncertainty of 0.20 eV for these calculated energies, equal to the measurement errors in the best measurements. A comparison of the energies calculated by Chen (1985) with the above mentioned calculations by the group of K.T.…”

Section: X-ray Absorption Linesmentioning

confidence: 79%

X-ray/UV campaign on the Mrk 279 outflow: Density diagnostics in Active Galactic Nuclei using O v K-shell absorption lines

Kaastra

Raassen

Mewe

et al. 2004

A&A

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Abstract.One of the main problems in modeling the ionised outflows in Active Galactic Nuclei is the unknown distance of the outflowing wind to the central source. Only if the density is known this distance can be determined through the ionisation parameter. Here we study density diagnostics based upon O  transitions. O  is known to have metastable levels that are density dependent. We study the population of those levels under photoionisation equilibrium conditions and determine for which parameter range they can have a significant population. We find that resonance line trapping plays an important role in reducing the critical densities above which the metastable population becomes important. We investigate the K-shell absorption lines from these metastable levels. Provided that there is a sufficient population of the metastable levels, the corresponding K-shell absorption lines are detectable and are well separated from the main absorption line originating from the ground state. We then present the Chandra LETGS spectrum of the Seyfert 1 galaxy Mrk 279 that may show for the first time the presence of these metastable level absorption lines. A firm identification is not yet possible due to both uncertainties in the observed wavelength of the strongest line as well as uncertainties in the predicted wavelength. If the line is indeed due to absorption from O , then we deduce a distance to the central source of one light week to a few light months, depending upon the importance of additional heating processes.

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Section: X-ray Absorption Linesmentioning

confidence: 79%

X-ray/UV campaign on the Mrk 279 outflow: Density diagnostics in Active Galactic Nuclei using O v K-shell absorption lines

Kaastra

Raassen

Mewe

et al. 2004

A&A

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“…To get a high-quality wave function, in present work, the number of angular-spin components ranges from 50 to 80, and the number of linear parameters ranges from 1,600 to 2,700. For the 4 P states, the parity (À1) …”

Section: Resultsmentioning

confidence: 99%

“…Early in the 1970s, the wavelengths and lifetimes for a number of transitions of B-like oxygen ion in the spectral region 100-5,000 Å were studied by the beam-foil technique [1][2][3]. Bruch et al [4] observed the high-resolution projectile Auger spectra of singly and doubly core-excited states for B-like O 3þ with the beam energy from 2 to 18 MeV. Later, Westerlind et al [5] investigated the lifetimes of the 1s 2 2s2p3p and 1s 2 2s2p3d quartet states for B-like O 3þ , using the beamfoil technique.…”

Section: Introduction Imentioning

confidence: 99%

Energies, fine structures, and radiative lifetimes for the multiexcited quartet states of B‐like oxygen

Sun

Feng

Lin

et al. 2011

Int J of Quantum Chemistry

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Energies for the multiexcited states 1s 2 2s2pnl and 1s 2 2p 2 nl 4 P e,o (n ! 2) of B-like oxygen are calculated using Rayleigh-Ritz variation method with configuration interaction. The mass polarization and relativistic corrections are obtained with firstorder perturbation theory. Configuration structures of the high-lying multiexcited series are identified by energies and contribution to normalization of angular-spin components. These structures are further checked by calculations of relativistic corrections and fine structure splittings. Hyperfine parameters and hyperfine coupling constants are calculated for the first time. Wavelengths including quantum electrodynamic effect and higher-order relativistic corrections and lifetimes are also calculated. These results are compared with available results in the literature.

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“…Several experimental observations [1][2][3][4][5][6][7][8] and theoretical data [8][9][10][11][12][13] for these core-excited states have been reported. As is well known in Rødbor et al [1][2][3][4], the Auger electron spectra of highly excited autoionizing levels of carbon, oxygen, and neon ions were studied by the projectile electrons' collision with rare gases or carbon foil. The x-ray spectra of carbon [5,6], magnesium [7], and silicon [8] ions are observed by foil excitation of fast ion beams and laser-induced plasma experiments.…”

Section: Introductionmentioning

confidence: 94%

Energies and the radiative and Auger transition rates of1s2p4resonances of B-like ions

2013

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Energy levels and the radiative and Auger transition rates of the 1s2p 4 2,4 L (L = S, P , D) resonances in the boron isoelectronic sequence are calculated using the saddle-point variation and saddle-point complex-rotation methods. Large-scale wave functions are used to saturate the functional space. Relativistic and mass polarization corrections are included by the first-order perturbation theory. The Auger branching ratios of the important decay channels for these core-excited states are calculated. The reliable transition wavelengths and Auger electron energies are used to identify available x-ray spectra and Auger electron spectra. Identifications of several unknown experimental lines from 1s2p 4 resonances are reported. The total radiative rates and total Auger rates of these 1s2p 4 resonances are also reported and discussed along with the increase of atomic number Z. It is found that the total Auger rates are several orders of magnitude greater than the total radiative rates in these low-Z ions.

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Projectile Auger spectra of gas- and foil-excited oxygen ions at MeV energies

Cited by 63 publications

References 37 publications

X-ray/UV campaign on the Mrk 279 outflow: Density diagnostics in Active Galactic Nuclei using O v K-shell absorption lines

X-ray/UV campaign on the Mrk 279 outflow: Density diagnostics in Active Galactic Nuclei using O v K-shell absorption lines

Energies, fine structures, and radiative lifetimes for the multiexcited quartet states of B‐like oxygen

Energies and the radiative and Auger transition rates of1s2p4resonances of B-like ions

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