References of "Biémont, Emile"
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See detailRadiative lifetime measurements and calculations in doubly ionized tantalum (Ta III)
Fivet, V.; Biémont, Emile ULg; Engström, L. et al

in Journal of Physics : B Atomic Molecular & Optical Physics (2008), 41

Radiative lifetimes of six odd-parity levels belonging to the 5d26p configuration of doubly ionized tantalum (Ta III) have been measured using the time-resolved-laser-inducedfluorescence technique ... [more ▼]

Radiative lifetimes of six odd-parity levels belonging to the 5d26p configuration of doubly ionized tantalum (Ta III) have been measured using the time-resolved-laser-inducedfluorescence technique. Supporting theoretical calculations, including core-polarization effects, have been performed to model configuration interaction and to estimate branching fractions. The excellent agreement between the theoretical and experimental lifetimes allows us to assess the reliability of the 206 calculated transition probabilities. It is expected that this new set of results will be useful to astrophysicists for the investigation of the chemical composition of stars. [less ▲]

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See detailLifetime and Landé factor measurements of 5p7p levels of Sn I by time-resolved laser spectroscopy
Zhang, Y.; Xu, J.; Zhang, W. et al

in Physical Review. A (2008), 78

Lifetimes for nine levels and Landé gJ factors for eight levels of the 5p7p configuration of neutral tin have been measured by the time-resolved fluorescence method and by the Zeeman quantum beat ... [more ▼]

Lifetimes for nine levels and Landé gJ factors for eight levels of the 5p7p configuration of neutral tin have been measured by the time-resolved fluorescence method and by the Zeeman quantum beat technique, respectively. A two-step laser excitation technique has been used for the measurements. The results obtained are compared with relativistic Hartree-Fock lifetime and gJ values taking core-polarization effects into account. [less ▲]

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See detailLaser-induced-fluorescence lifetime measurements and relativistic Hartree-Fock oscillator strength calculations in singly ionized platinum
Quinet, Pascal ULg; Palmeri, P.; Fivet, V. et al

in Physical Review. A (2008), 77

Radiative lifetimes of eight odd-parity states of Pt II, in the energy range from 51 408 to 64 388 cm−1, have been measured by means of the time-resolved laser-induced-fluorescence technique. Free, singly ... [more ▼]

Radiative lifetimes of eight odd-parity states of Pt II, in the energy range from 51 408 to 64 388 cm−1, have been measured by means of the time-resolved laser-induced-fluorescence technique. Free, singly ionized platinum ions were obtained in a laser-produced plasma and a tunable laser with 1.5 ns duration pulse was used to selectively excite the Pt+ ions. The comparison of the experimental results with relativistic Hartree-Fock calculations emphasizes the importance of valence-valence correlation and of core-polarization effects in this complex ion. A new and extensive set of calculated oscillator strengths and transition probabilities is reported in the present paper. [less ▲]

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See detailTransition probabilities in Au III
Enzonga Yoca, S.; Biémont, Emile ULg; Delahaye, F. et al

in Physica Scripta (2008), 78

Theoretical transition probabilities are reported for doubly ionized gold (Au III). They have been obtained through the use of two different independent theoretical approaches, i.e. the SUPERSTRUCTURE ... [more ▼]

Theoretical transition probabilities are reported for doubly ionized gold (Au III). They have been obtained through the use of two different independent theoretical approaches, i.e. the SUPERSTRUCTURE code and a HFR model including valence–valence and core–valence configuration interaction in a detailed way. The new scale of A-values is assessed through the comparison of the two sets of results and also through the use of a model similar to the one selected for an isoelectronic ion, i.e. Pt II, for which accurate laser-induced-fluorescence lifetimes have been measured recently. [less ▲]

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See detailATOMIC STRUCTURES OF HEAVY ELEMENTS : RECENT PROGRESS AND PERSPECTIVES
Biémont, Emile ULg; Fivet, V.; Palmeri, P. et al

Conference (2008)

In the present paper, we discuss some recent advances concerning the determination of new radiative parameters (transition probabilities, oscillator strengths, radiative lifetimes, branching fractions ... [more ▼]

In the present paper, we discuss some recent advances concerning the determination of new radiative parameters (transition probabilities, oscillator strengths, radiative lifetimes, branching fractions, Landé factors) in heavy ions. We also emphasize the difficulties that are frequently met in the field and that sometimes prevent obtaining accurate atomic data for the transitions of astrophysical interest. We concentrate particularly on the determination of radiative parameters for selected rare-earth (RE) ions (lanthanides and actinides) and for some atoms and ions of the sixth row of the periodic table. [less ▲]

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See detailExperimental and theoretical transition probabilities in singly ionized gold
Biémont, Emile ULg; Blagoev, K.; Fivet, V. et al

in Monthly Notices of the Royal Astronomical Society (2007), 380(4), 1581-1588

Absolute transition probabilities have been measured for lines originating from the 5d(9)6d and 5d(9)7s electronic configurations in the spectrum of singly ionized gold (Au II). The laser-induced ... [more ▼]

Absolute transition probabilities have been measured for lines originating from the 5d(9)6d and 5d(9)7s electronic configurations in the spectrum of singly ionized gold (Au II). The laser-induced breakdown spectroscopy has been applied to free gold atoms and ions produced by laser ablation. Absolute transition probabilities have been determined using the branching fraction and the Boltzmann plot methods. Theoretical branching fractions as well as radiative lifetime values have also been obtained by a relativistic Hartree-Fock method taking core polarization and configuration interaction effects into account. The new results are compared with previous results when available. [less ▲]

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See detailAtomic data for radioactive elements RaI, RaII, AcI and AcII and application to their detection in HD 101065 and HR 465
Quinet, Pascal ULg; Argante, C.; Fivet, V. et al

in Astronomy and Astrophysics (2007), 474(1), 307-314

Radiative data for transitions of astrophysical interest in radioactive elements Ra I, Ra II, Ac I and Ac II have been computed using a semi- empirical relativistic Hartree- Fock approach including core ... [more ▼]

Radiative data for transitions of astrophysical interest in radioactive elements Ra I, Ra II, Ac I and Ac II have been computed using a semi- empirical relativistic Hartree- Fock approach including core polarization effects. Most of the oscillator strengths reported in the present paper are new. A possible detection of radium ( Ra II) and actinium ( Ac II) in the spectrum of the stars HD 101065 and HR 465 is examined and discussed. [less ▲]

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See detailTransition probabilities in singly ionized promethium and the identification of PmII lines in Przybylski's star and HR 465
Fivet, V.; Quinet, Pascal ULg; Biémont, Emile ULg et al

in Monthly Notices of the Royal Astronomical Society (2007), 380(2), 771-780

The first theoretical transition probabilities are obtained for a set of 46 Pm ii transitions of astrophysical interest. These data fill in a gap in astrophysics and will allow to establish, on a firmer ... [more ▼]

The first theoretical transition probabilities are obtained for a set of 46 Pm ii transitions of astrophysical interest. These data fill in a gap in astrophysics and will allow to establish, on a firmer basis, the presence of some lines of this radioactive element in the spectra of chemically peculiar stars and, consequently, a quantitative investigation of the stellar Pm abundance. A search for Pm ii lines in Przybylski's star (HD 101065) and in HR 465 is reported and discussed, supporting the detection of this ion. A more detailed quantitative analysis is awaiting the availability of dedicated model atmospheres for these stars. [less ▲]

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See detailRelativistic atomic data for EUV and X-ray lines in the highly charged Zn-like ions from Yb40+ to U62+
Quinet, Pascal ULg; Biémont, Emile ULg; Palmeri, P. et al

in Atomic Data and Nuclear Data Tables (2007), 93(5), 711-729

The wavelengths and transition probabilities for EUV and X-ray lines in the spectra from Yb XLI to U LXIII along the zinc isoelectronic sequence have been calculated using a multiconfiguration Dirac-Fock ... [more ▼]

The wavelengths and transition probabilities for EUV and X-ray lines in the spectra from Yb XLI to U LXIII along the zinc isoelectronic sequence have been calculated using a multiconfiguration Dirac-Fock (MCDF) model. Results are reported for the 4S(2) -4s4p, 4s4p-4p(2), and 4s4p-4s4d transitions. A comparison of the calculated wavelengths with the few experimental results available is also presented. (c) 2007 Elsevier Inc. All rights reserved. [less ▲]

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See detailLifetime and transition probability determination in xenon ions - The cases of XeVII and XeVIII
Biémont, Emile ULg; Clar, Mathieu ULg; Fivet, V. et al

in European Physical Journal D -- Atoms, Molecules, Clusters & Optical Physics (2007), 44(1), 23-33

Radiative lifetimes have been calculated for 15 levels of Xe VII belonging to the configurations 5s5p, 5p(2), 5s5d, 5s6s, 5p5d, 4f5p, 5p5d and 5s5f and for 4 levels of the 5p and 5d configurations of Xe ... [more ▼]

Radiative lifetimes have been calculated for 15 levels of Xe VII belonging to the configurations 5s5p, 5p(2), 5s5d, 5s6s, 5p5d, 4f5p, 5p5d and 5s5f and for 4 levels of the 5p and 5d configurations of Xe VIII. A relativistic Hartree-Fock approach including core-polarization effects, on the one hand, and a purely relativistic multiconfiguration Dirac-Fock method, on the other hand, have been used for the calculations. The accuracy of the present set of results has been assessed through comparisons with radiative lifetime measurements obtained by beam-foil spectroscopy. A good agreement between theory and experiment is observed for most of the levels. A new set of transition probabilities is proposed for 169 transitions of Xe VII and 45 transitions of Xe VIII. [less ▲]

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See detailRadiative decay from the 7s(1/2) level in Pb+ and transition probabilities of astrophysical interest in Pb+ and Bi++
Quinet, Pascal ULg; Biémont, Emile ULg; Palmeri, P. et al

in Journal of Physics B-Atomic Molecular and Optical Physics (2007), 40(10), 1705-1712

In the present work, we report on experimental and theoretical determination of the decay rates from the 7s(1)/2 state in singly ionized lead. Lifetime measurements performed using time-resolved laser ... [more ▼]

In the present work, we report on experimental and theoretical determination of the decay rates from the 7s(1)/2 state in singly ionized lead. Lifetime measurements performed using time-resolved laser-induced fluorescence spectroscopy and lifetime computations carried out with themulticonfiguration Dirac-Fock method allow us to solve the discrepancies previously observed between theory and experiment for this level. New transition probabilities are proposed for the two depopulation channels, i. e. the 6p(1/2-7s1/2) and 6p(3/2-7s1/2) transitions of astrophysical interest in Pb II and Bi III, respectively. [less ▲]

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See detailWavelengths and transition probabilities in heavy Ge-like ions (70 <= Z <= 92)
Palmeri, P.; Quinet, Pascal ULg; Biémont, Emile ULg et al

in Atomic Data and Nuclear Data Tables (2007), 93(3), 355-374

Wavelengths and transition probabilities have been calculated for the 4s(2)4P(2) -4s4P(3) and 4s(2)4p(2) -4s(2)4p4d allowed transitions and for the forbidden (M1 and E2) transitions occurring within the ... [more ▼]

Wavelengths and transition probabilities have been calculated for the 4s(2)4P(2) -4s4P(3) and 4s(2)4p(2) -4s(2)4p4d allowed transitions and for the forbidden (M1 and E2) transitions occurring within the ground configuration (4s(2)4p(2)) in the heavy Ge-like ions with Z = 70-92. The fully relativistic multiconfiguration Dirac-Fock method taking into account both the correlations within the n = 4 complex and the QED effects has been used for the calculations. The present results are compared to and agree well with recent electron-beam ion-trap measurements in tungsten, osmium, gold, bismuth, thorium, and uranium. (C) 2006 Elsevier Inc. All rights reserved. [less ▲]

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See detailTransition probabilities in complex ions: The case of americium
Fivet, V.; Quinet, Pascal ULg; Biémont, Emile ULg

in Journal of Electron Spectroscopy and Related Phenomena (2007), 156

We report on the first calculations of transition probabilities in neutral americium, a heavy radioactive element belonging to the actinide group. A relativistic Hartree-Fock approach, including core ... [more ▼]

We report on the first calculations of transition probabilities in neutral americium, a heavy radioactive element belonging to the actinide group. A relativistic Hartree-Fock approach, including core-polarization effects, has been used for obtaining branching fractions and radiative lifetimes for some low-lying levels belonging to the 7s7p configuration. A comparison with the few experimental results available shows reasonable agreement between theory and experiment. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailTransition probabilities and lifetimes for atoms and ions from the sixth row of the periodic table and the database DESIRE
Fivet, V.; Quinet, Pascal ULg; Palmeri, P. et al

in Journal of Electron Spectroscopy and Related Phenomena (2007), 156

We have started a systematic investigation of the radiative properties of the elements of the sixth row of the periodic table. Using a combination of experimental radiative lifetimes obtained with the ... [more ▼]

We have started a systematic investigation of the radiative properties of the elements of the sixth row of the periodic table. Using a combination of experimental radiative lifetimes obtained with the time-resolved laser-induced fluorescence (LIF) technique and of theoretical branching fractions (BF) calculated with a HFR approach taking configuration interaction and core-polarization effects into account, transition probabilities have been deduced for a number of transitions of astrophysical interest. So far results have been obtained for the elements Ta, Re, Os, Ir, Tl or An or their ions. The results obtained are stored in the database DatabasE for the SIxth Row Elements (DESIRE), an extension of the database DREAM, which will be progressively created on a web site of the University of Mons-Hainaut in Belgium. In the present paper, some emphasis is put on the procedures followed to obtain the new results but also on the difficulties associated with their determination. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailLaser-probing measurements and calculations of lifetimes of the 5d D-2(3/2) and 5d D-2(5/2) metastable levels in BaII
Gurell, J.; Biémont, Emile ULg; Blagoev, K. et al

in Physical Review A (2007), 75(5), 1-6

The two metastable levels 5d(2)D(3/2) and 5d(2) D-5/2 in Ba II both show extremely long lifetimes of the order of several tens of seconds each. This has been found both by experiments and by theoretical ... [more ▼]

The two metastable levels 5d(2)D(3/2) and 5d(2) D-5/2 in Ba II both show extremely long lifetimes of the order of several tens of seconds each. This has been found both by experiments and by theoretical predictions. The small transition probabilities associated with these two levels make them interesting and challenging for theoreticians as well as for experimentalists. Several calculations and measurements of these two lifetimes have been made previously but discrepancies between the results are present. This article presents values of ??? = 89.4 +/- 15.6 s for the D-2(3/2) level and ??? = 32.0 +/- 4.6 s for the D-2(5/2) level measured in a beam-laser experiment performed at the ion storage ring CRYRING. These values are supported by our new calculations resulting in ???= 82.0 s for the D-2(3/2) level and ???= 31.6 s for the D-2(5/2) level. [less ▲]

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See detailWavelengths and transition probabilities for n= 4 -> n '=4 transitions in heavy Cu-like ions (70 <= Z <= 92)
Palmeri, P.; Quinet, Pascal ULg; Biémont, Emile ULg et al

in Atomic Data and Nuclear Data Tables (2007), 93(3), 537-547

Wavelengths and transition probabilities have been calculated for the n = 4 ->-> n' = 4 allowed transitions in the heavy Cu-like ions with Z = 70-92. Fully relativistic multiconfiguration Dirac-Fock (MCDF ... [more ▼]

Wavelengths and transition probabilities have been calculated for the n = 4 ->-> n' = 4 allowed transitions in the heavy Cu-like ions with Z = 70-92. Fully relativistic multiconfiguration Dirac-Fock (MCDF) calculations were carried out. They take into account the correlations within the it = 4 complex, the core-valence n = 3 ->-> n' = 4 virtual excitations, and quantum electrodynamics effects. The present results are compared to and agree well with recent electron-beam ion-trap (EBIT) measurements in ytterbium, tungsten, osmium, gold, lead, bismuth, thorium, and uranium. (C) 2006 Elsevier Inc. All rights reserved. [less ▲]

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See detailImproved atomic data for iridium atom (Ir I) and ion (Ir II) and the solar content of iridium
Xu, H. L.; Svanberg, S.; Quinet, Pascal ULg et al

in Journal of Quantitative Spectroscopy & Radiative Transfer (2007), 104(1), 52-70

From a combination of radiative lifetime measurements, performed with a time-resolved laser-induced fluorescence technique, for nine odd-parity levels of Ir I and four odd-parity levels of Ir 11 and ... [more ▼]

From a combination of radiative lifetime measurements, performed with a time-resolved laser-induced fluorescence technique, for nine odd-parity levels of Ir I and four odd-parity levels of Ir 11 and branching fraction calculations, extended sets of transition probabilities have been derived for transitions of astrophysical interest. The new results are compared with the few experimental data available in the literature and a good agreement is found. They extend considerably the previous sets of transition probabilities available in the literature. Implications of the new results regarding the solar content of iridium are briefly discussed. (c) 2006 Elsevier Ltd. All rights reserved. [less ▲]

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See detailDecay of metastable states in NdII
Biémont, Emile ULg; Ellmann, A.; Lundin, P. et al

in European Physical Journal D -- Atoms, Molecules, Clusters & Optical Physics (2007), 41(2), 211-219

The difficulty associated with an accurate determination of transition rates for forbidden lines in lowly ionized heavy elements is illustrated in the case of Nd II. We have investigated the radiative ... [more ▼]

The difficulty associated with an accurate determination of transition rates for forbidden lines in lowly ionized heavy elements is illustrated in the case of Nd II. We have investigated the radiative decay of the low-lying metastable levels in Nd+ including the two levels 4f(4)(I-5) 5d K-6(11/2) and 4f(4)(I-5) 5d I-6(13/2). In these two particular cases, using di. erent theoretical approaches, we. nd that the decay is dominated by the M1 channels but that the E2 contributions are of the same order of magnitude. These levels have also been studied experimentally by lifetime measurements with the heavy ion storage ring CRYRING of Stockholm University. The difficulties encountered when performing such experiments are underlined and discussed. [less ▲]

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See detailRadiative parameters for some transitions arising from the 3d(9)4d and 3d(8)4s(2) electronic configurations in CuII spectrum
Ortiz, M.; Mayo, R.; Biémont, Emile ULg et al

in Journal of Physics B-Atomic Molecular and Optical Physics (2007), 40(1), 167-176

Transition probabilities of 41 transitions originating from the 3d(9)4d and 3d(8)4s(2) electronic configurations of singly ionized copper have been determined using laser-induced breakdown spectroscopy ... [more ▼]

Transition probabilities of 41 transitions originating from the 3d(9)4d and 3d(8)4s(2) electronic configurations of singly ionized copper have been determined using laser-induced breakdown spectroscopy. The Cu II ions have been produced by laser ablation. The experimental relative transition probabilities have been converted into an absolute scale using measured branching fractions and theoretical radiative lifetimes of the corresponding upper states obtained by a relativistic Hartree-Fock method taking core-polarization and configuration interaction effects into account. Comparison of the new results with previously available data is also presented. [less ▲]

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See detailRadiative decay of the 4d(5)(S-6)5p z(5,7)P(o) states in TcII: comparison along the homologous and isoelectronic sequences. Application to astrophysics
Palmeri, P.; Quinet, Pascal ULg; Biémont, Emile ULg et al

in Monthly Notices of the Royal Astronomical Society (2007), 374(1), 63-71

Using three independent theoretical approaches (CA, HFR+CP, AUTOSTRUCTURE), oscillator strengths have been calculated for a set of Tc II transitions of astrophysical interest and the reliability of their ... [more ▼]

Using three independent theoretical approaches (CA, HFR+CP, AUTOSTRUCTURE), oscillator strengths have been calculated for a set of Tc II transitions of astrophysical interest and the reliability of their absolute scale has been assessed. The examination of the spectra emitted by some Ap stars has allowed the identification of Tc II transitions in HD 125248. This Tc II detection should however await confirmation from spectral synthesis relying on dedicated model atmospheres. New partition functions are also provided for Tc I, TcII and Tc III for temperatures ranging between 4000 and 13 000 K. [less ▲]

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