References of "Palmeri, P."
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See detailAb initio calculation of the 66 low lying electronic states of HeH+ : adiabatic and diabatic representations
Loreau, J; Liévin, J; Palmeri, P et al

in Journal of Physics : B Atomic Molecular & Optical Physics (2010), 43

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See detailRadiative decay rates for W I, W II and W III allowed and forbidden transitions of interest for spectroscopic diagnostics in fusion plasmas
Quinet, Pascal ULg; Vinogradoff, V.; Palmeri, P. et al

in Journal of Physics : B Atomic Molecular & Optical Physics (2010), 43

Transition probabilities for allowed and forbidden lines in neutral, singly ionized and doubly ionized tungsten are discussed in the present paper. For the electric dipole transitions, recommended values ... [more ▼]

Transition probabilities for allowed and forbidden lines in neutral, singly ionized and doubly ionized tungsten are discussed in the present paper. For the electric dipole transitions, recommended values are proposed from a critical evaluation of the data available in the literature. For the magnetic dipole and electric quadrupole transitions, for which no data have been published so far, a new set of radiative rates has been obtained using a relativistic Hartree–Fock approach including core-polarization effects. The tables summarizing the compiled data are expected to be useful for plasma modelling in fusion reactors. [less ▲]

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See detailTransition probabilities of astrophysican interest in the niobium ions (Nb II and Nb III)
Nilsson, H.; Hartman, H.; Engström, L. et al

in Astronomy and Astrophysics (2010)

Aims. We attempt to derive accurate transition probabilities for astrophysically interesting spectral lines of Nb ii and Nb iii and determine the niobium abundance in the Sun and metal-poor stars rich in ... [more ▼]

Aims. We attempt to derive accurate transition probabilities for astrophysically interesting spectral lines of Nb ii and Nb iii and determine the niobium abundance in the Sun and metal-poor stars rich in neutron-capture elements. Methods. We used the time-resolved laser-induced fluorescence technique to measure radiative lifetimes in Nb ii. Branching fractions were measured from spectra recorded using Fourier transform spectroscopy. The radiative lifetimes and the branching fractions were combined yielding transition probabilities. In addition, we calculated lifetimes and transition probablities in Nb ii and Nb iii using a relativistic Hartree-Fock method that includes core polarization. Abundances of the sun and five metal-poor stars were derived using synthetic spectra calculated with the MOOG code, including hyperfine broadening of the lines. Results. We present laboratory measurements of 17 radiative lifetimes in Nb ii. By combining these lifetimes with branching fractions for lines depopulating the levels, we derive the transition probabilities of 107 Nb ii lines from 4d35p configuration in the wavelength region 2240−4700 Å. For the first time, we present theoretical transition probabilities of 76 Nb III transitions with wavelengths in the range 1430−3140 Å. The derived solar photospheric niobium abundance log = 1.44 ± 0.06 is in agreement with the meteoritic value. The stellar Nb/Eu abundance ratio determined for five metal-poor stars confirms that the r-process is a dominant production method for the n-capture elements in these stars. [less ▲]

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See detailLandé g-factors along the sixth row of the periodic table
Biémont, Emile ULg; Palmeri, P.; Quinet, Pascal ULg

in Journal of Physics : B Atomic Molecular & Optical Physics (2010), 43

Land´e g-factors are calculated, in intermediate coupling, for 2084 levels belonging to atoms or ions of the sixth row of the periodic table. Extensive configuration interaction and relativistic effects ... [more ▼]

Land´e g-factors are calculated, in intermediate coupling, for 2084 levels belonging to atoms or ions of the sixth row of the periodic table. Extensive configuration interaction and relativistic effects are included in the framework of the relativistic Hartree–Fock approximation including core-polarization effects. The results have been refined using least-squares fittings of the Hamiltonian eigenvalues to the observed energy levels (when available). The new results fill in some gaps in the existing data for a large number of levels belonging to ions of astrophysical interest and are expected to be useful for investigating magnetic fields in CP stars. [less ▲]

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See detailHD 65949: Rosetta Stone or Red Herring
Cowley, C. R.; Hubrig, S.; Palmeri, P. et al

in Monthly Notices of the Royal Astronomical Society (2010), 405

HD 65949 is a late B star with exceptionally strong Hg II λ3984, but it is not a typical HgMn star. The Re II spectrum is of extraordinary strength. Abundances or upper limits are derived here for 58 ... [more ▼]

HD 65949 is a late B star with exceptionally strong Hg II λ3984, but it is not a typical HgMn star. The Re II spectrum is of extraordinary strength. Abundances or upper limits are derived here for 58 elements based on a model with Teff = 13 100K and log(g) = 4.0. Even-Z elements through nickel show minor deviations from solar abundances. Anomalies among the odd-Z elements through copper are mostly small. Beyond the iron peak, a huge scatter is found. Enormous enhancements are found for the elements rhenium through mercury (Z = 75–80). We note the presence of Th III in the spectrum. The abundance pattern of the heaviest elements resembles the N = 126 r-process peak of solar material, though not in detail. An odd-Z anomaly appears at the triplet (Zr Nb Mo), and there is a large abundance jump between Xe (Z = 54) and Ba (Z = 56). These are signatures of chemical fractionation. We find a significant correlation of the abundance excesses with second ionization potentials for elements withZ > 30. If this is not a red herring (false lead), it indicates the relevance of photospheric or near-photospheric processes. Large excesses (4–6 dex) require diffusion from deeper layers with the elements passing through a number of ionization stages. That would make the correlation with second ionization potential puzzling. We explore a model with mass accretion of exotic material followed by the more commonly accepted differentiation by diffusion. That model leads to a number of predictions which challenge future work. New observations confirm the orbital elements of Gieseking and Karimie, apart from the systemic velocity, which has increased. Likely primary and secondary masses are near 3.3 and 1.6 M , with a separation of ca. 0.25 au. New atomic structure calculations are presented in two appendices. These include partition functions for the first through third spectra of Ru, Re and Os, as well as oscillator strengths in the Re II spectrum. [less ▲]

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See detailK-shell photoionization and photoabsorption of Ne, Mg, Si, S, Ar and Ca
Witthoeft, M; Bautista, M A; Mendoza, C et al

in Astrophysical Journal Supplement Series (2009), 182

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See detailNitrogen K-shell photoabsorption
Garcia, J; Kallman, T R; Witthoeft, M et al

in Astrophysical Journal Supplement Series (2009), 185

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See detailSpectrum synthesis modeling of the X-ray spectrum of GRO J1655-40 during the 2005 outburst
Kallman, T R; Bautista, M A; Goriely, S et al

in Astrophysical Journal (2009), 701

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See detailRadiative transition rates and collision strengths for Si II
Bautista, M A; Quinet, Pascal ULg; Palmeri, P et al

in Astronomy and Astrophysics (2009), 508

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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 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 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 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 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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