References of "Quinet, Pascal"
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See detailBranching fractions and A values in singly ionized tantalum (Ta II)
Quinet, Pascal ULg; Fivet, V.; Palmeri, P. et al

in Astronomy and Astrophysics (2009), 493

Aims. We report on the theoretical and experimental lifetimes of Ta II, and calculated branching fractions for selected transitions. Methods. The theoretical data are obtained by means of a relativistic ... [more ▼]

Aims. We report on the theoretical and experimental lifetimes of Ta II, and calculated branching fractions for selected transitions. Methods. The theoretical data are obtained by means of a relativistic Hartree-Fock method with detailed attention to correlation effects. The experimental lifetimes are measured with the time-resolved, laser-induced, fluorescence technique. Results. The calculated results are in good agreement with both previously known and new experimental lifetimes. New transition probabilities have been deduced for a set of Ta II transitions of astrophysical interest. [less ▲]

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See detailRadiative lifetimes along even-parity J = 1, 2 Rydberg series of neutral tin
Zhang, W.; You, S.; Sun, C. et al

in European Physical Journal D -- Atoms, Molecules, Clusters & Optical Physics (2009), 55

Using the time-resolved laser-induced fluorescence (LIF) technique in a tin atomic beam, 40 natural radiative lifetimes have been measured for the even-parity J = 1 5pnp (n = 10–13, 15–19) and J = 2 5pnp ... [more ▼]

Using the time-resolved laser-induced fluorescence (LIF) technique in a tin atomic beam, 40 natural radiative lifetimes have been measured for the even-parity J = 1 5pnp (n = 10–13, 15–19) and J = 2 5pnp (n = 10–13, 15–19, 27, 31, 32), 5pnf (n = 4, 5, 9–19, 22, 23) levels along the Rydberg series and for all the 5p8p perturbing levels of neutral tin with energies in the range 52263.8 to 59099.9 cm−1. A two-step laser excitation scheme was used in the experiment. A multiconfigurational relativistic Hartree-Fock (HFR) calculation taking core-polarization effects into account has also been performed for the even-parity states for testing the ability of this approach to correctly predict the radiative properties of tin atom. Through an analysis of the energy levels structure by the multichannel quantum defect theory (MQDT), the channel admixture coefficients have been obtained and used to fit the theoretical lifetimes to the experimental ones in order to predict new values for the levels not measured. A generally good overall agreement between experimental and theoretical MQDT and HFR lifetimes has been achieved except for a few levels. [less ▲]

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See detailLand´e factors for even-parity 5pnp and 5pnf J = 1, 2 levels along the Rydberg series of Sn I
Xu, J.; You, S.; Zhang, Y. et al

in Journal of Physics : B Atomic Molecular & Optical Physics (2009), 42

Land´e g-factors have been measured by time-resolved laser-induced fluorescence and Zeeman quantum-beat techniques for the even-parity levels of the J = 1 5pnp (n = 11–13, 15–19) and J = 2 5pnp (n = 11–13 ... [more ▼]

Land´e g-factors have been measured by time-resolved laser-induced fluorescence and Zeeman quantum-beat techniques for the even-parity levels of the J = 1 5pnp (n = 11–13, 15–19) and J = 2 5pnp (n = 11–13, 15–19, 31, 32), 5pnf (n = 4, 5, 9–19, 22, 23) Rydberg series and for all the 5p7p and 5p8p perturbing levels of neutral tin. A two-colour two-step excitation scheme was used in the experiment. The experimental results have been compared with theoretical g-values obtained by the multichannel quantum defect theory and the relativistic Hartree–Fock theory, respectively. In most cases, the theoretical values agree well with the experimental data. [less ▲]

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See detailExperimental and theoretical radiative decay rates for highly excited ruthenium atomic levels and the solar abundance of ruthenium
Fivet, V.; Quinet, Pascal ULg; Palmeri, P. et al

in Monthly Notices of the Royal Astronomical Society (2009), 396

The solar photospheric abundance of ruthenium is revised on the basis of a new set of oscillator strengths derived for Ru I transitions with wavelengths in the spectral range 2250–4710 Å. The new ... [more ▼]

The solar photospheric abundance of ruthenium is revised on the basis of a new set of oscillator strengths derived for Ru I transitions with wavelengths in the spectral range 2250–4710 Å. The new abundance value (in the usual logarithmic scale where the solar hydrogen abundance is equal to 12.00), ARu = 1.72 ± 0.10, is in agreement with the most recent meteoritic result, ARu = 1.76 ± 0.03. The accuracy of the transition probabilities, obtained using a relativistic Hartree–Fock model including core-polarization effects, has been assessed by comparing the theoretical lifetimes with previous experimental results. A comparison is also made with new measurements performed in this work by the time-resolved laser-induced fluorescence spectroscopy for 10 highly excited odd-parity levels of Ru I [less ▲]

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See detailLifetime measurements in Ru II and calculated oscillator strengths in Ru II and Ru III
Palmeri, P.; Quinet, Pascal ULg; Fivet, V. et al

in Journal of Physics : B Atomic Molecular & Optical Physics (2009), 42

A new set of theoretical f -values is reported for 178 Ru II transitions of astrophysical interest, involving energy levels below 58 000 cm−1. The theoretical model, including core-polarization effects ... [more ▼]

A new set of theoretical f -values is reported for 178 Ru II transitions of astrophysical interest, involving energy levels below 58 000 cm−1. The theoretical model, including core-polarization effects, has been tested by comparing theoretical lifetimes with new measurements performed by time-resolved laser-induced fluorescence spectroscopy for 23 4d6(5D)5p odd levels of Ru II and by comparing theoretical and experimental Land´e g-factors. The first set of transition probabilities is proposed for 25 strong lines depopulating the 4d55p 5,7P◦ terms of Ru III. The new results will allow quantitative investigations of stellar spectra and allow the astrophysicists to refine the ruthenium abundance in stars. [less ▲]

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See detailRadiative and Auger decay data for modeling nickel K lines
Palmeri, P; Quinet, Pascal ULg; Mendoza, C et al

in Astrophysical Journal Supplement Series (2008), 179

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See detailRadiative and Auger decay of K-vacancy levels in the Ne, Mg, Si, S, Ar and Ca isonuclear sequences
Palmeri, P; Quinet, Pascal ULg; Mendoza, C et al

in Astrophysical Journal Supplement Series (2008), 177

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See detailThe spectra of massive stars with GAIA
Bouret, J C; Lanz, T; Frémat, Y et al

in Revista Mexicana de Astronomía y Astrofísica (2008), 33

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See detailRadiative data in the Zr I spectrum obtained by Laser Induced Fluorescence
Malcheva, G.; Mayo, R.; Ortiz, M. et al

Conference (2008)

Radiative lifetimes of 17 excited states in Zr I, in the energy interval 29000 – 40974 cm-1, have been investigated using the Time-Resolved Laser-Induced Fluorescence (TR-LIF) method. The levels belong to ... [more ▼]

Radiative lifetimes of 17 excited states in Zr I, in the energy interval 29000 – 40974 cm-1, have been investigated using the Time-Resolved Laser-Induced Fluorescence (TR-LIF) method. The levels belong to the 4d25s5p, 4d35p and 4d5s25p electronic configurations were excited in a single - step process from levels belonging to the ground 4p25s2 a 3F or to low-lying 4p25s2 a 3P, a 5F terms. For 14 levels, the lifetimes have been measured for the first time. Experimental results are compared with theoretical calculations performed with a multiconfigurational relativistic Hartree–Fock method including core polarization effects. [less ▲]

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See detailLifetime measurements and calculated transition probabilities in WIII
Palmeri, P.; Quinet, Pascal ULg; Fivet, V. et al

in Physica Scripta (2008), 78

New experimental lifetimes for two levels in doubly ionized tungsten, W III, have been obtained using the time-resolved laser-induced-fluorescence technique. Theoretical oscillator strengths obtained from ... [more ▼]

New experimental lifetimes for two levels in doubly ionized tungsten, W III, have been obtained using the time-resolved laser-induced-fluorescence technique. Theoretical oscillator strengths obtained from a HFR calculation including the effects of core-polarization are reported for all transitions from levels below E < 70 000 cm−1 and with log g f > −2, thus greatly extending our knowledge of the radiative data in W III. Good agreement is found between the calculated lifetimes and the experimental values from this and previous works. These new results fill a gap in the available data for this ion which is expected to play an important role in fusion reactors. [less ▲]

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See detailLifetime measurements and transition probability calculations in singly ionized tungsten (WII)
Nilsson, H.; Engström, L.; Lundberg, H. et al

in European Physical Journal D -- Atoms, Molecules, Clusters & Optical Physics (2008), 49

New measurements of radiative lifetimes for 9 levels in singly ionized tungsten (Wii) have been performed with the time-resolved laser-induced-fluorescence technique. Transition probabilities have been ... [more ▼]

New measurements of radiative lifetimes for 9 levels in singly ionized tungsten (Wii) have been performed with the time-resolved laser-induced-fluorescence technique. Transition probabilities have been obtained from a combination of experimental lifetimes and theoretical branching fractions. The reliability of the present results is assessed through the good agreement observed between the calculated lifetimes and the experimental values from this work and from previous publications. These new results fill in a gap in the available data for this atomic species particularly important for fusion reactors. [less ▲]

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See detailLifetimes of metastable levels of singly ionized titanium: theory and experiment
Palmeri, P.; Quinet, Pascal ULg; Biémont, Emile ULg et al

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

This paper presents new theoretical lifetimes of metastable levels in singly ionized titanium, Ti II. Along with the lifetimes, transition probabilities for several decay channels from these metastable ... [more ▼]

This paper presents new theoretical lifetimes of metastable levels in singly ionized titanium, Ti II. Along with the lifetimes, transition probabilities for several decay channels from these metastable levels are presented. The calculations are supported by experimental lifetime determinations of the 3d3 b 2D5/2 and 3d2(3P)4s b 2P3/2 levels along with revised values of the previously published lifetimes of the 3d2(3P)4s b 4P5/2 and 3d2(3P)4s b 2P1/2 levels originating partly from a reanalysis utilizing a recently developed method applied on the previously recorded data and partly from new measurements. The presented theoretical investigation of lifetimes of metastable levels in Ti II shows that the HFR calculations are in general compatible with measurements performed using the ion storage ring CRYRING of Stockholm University. The transition probabilities of forbidden lines derived from the new lifetime values will be useful for the diagnostics of low density laboratory or astrophysical plasmas, particularly those encountered in the strontium filament found in the ejecta of η Carinae. [less ▲]

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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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