References of "Biémont, Emile"
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See detailTransition probabilities in Xe V
Biémont, Emile ULg; Quinet, Pascal ULg; Zeippen, C. J.

in Physica Scripta (2005), 71(2), 163-169

Transition probabilities have been calculated with the pseudorelativistic Hartree-Fock (HFR) approach in which core-polarization effects have been included for Deltan = 0 and Deltan = 1 transitions ... [more ▼]

Transition probabilities have been calculated with the pseudorelativistic Hartree-Fock (HFR) approach in which core-polarization effects have been included for Deltan = 0 and Deltan = 1 transitions connecting the 5s(2)5p(2), 5s(2)5p6p. 5s(2)5p4f and the 5s5p(3). 5s(2)5p5d and 5s(2)5p6s configurations of Xe V. The accuracy of the present set of results is partly assessed through comparisons with the few experimental radiative lifetimes available. The reasons for the discrepancies between theory and experiment are outlined. [less ▲]

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See detailTransition probabilities for lines from 4d96s, 4d95d of Ag II spectrum and from 3d94d of Cu II lines
Biémont, Emile ULg; Blagoev, K.; Campos, J. et al

Conference (2005)

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See detailLes unités de division du temps
Biémont, Emile ULg

in Bulletin de la Société Royale des Sciences de Liège (2005), 74(4), 243-269

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See detailAstronomes célèbres et astronomes moins connus ... (6) John Flamsteed
Biémont, Emile ULg

in Galactée (2005), 46

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See detailRecent advances and difficulties in oscillator strength determination for rare-earth elements and ions
Biémont, Emile ULg

in Physica Scripta (2005), T119

Recent advances regarding radiative parameters determination for rare- earth atoms and ions are briefly discussed. In particular the difficulties associated with both the theoretical and the experimental ... [more ▼]

Recent advances regarding radiative parameters determination for rare- earth atoms and ions are briefly discussed. In particular the difficulties associated with both the theoretical and the experimental investigations of the elements or ions of this group are emphasized. The present status of the DREAM database is also briefly described. [less ▲]

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See detailRadiative parameters for some transitions in Cu(II) and Ag(II) spectrum
Biémont, Emile ULg; Blagoev, K.; Campos, J. et al

in Journal of Electron Spectroscopy & Related Phenomena (2005), 144-147

Radiative parameters for transitions depopulating the levels belonging to the 3d84s2 configuration of Cu(II) and 4d96s and 4d95d configurations of Ag(II) have been obtained both theoretically and ... [more ▼]

Radiative parameters for transitions depopulating the levels belonging to the 3d84s2 configuration of Cu(II) and 4d96s and 4d95d configurations of Ag(II) have been obtained both theoretically and experimentally. On the experimental side, a laser-produced plasma was used as a source of Cu(II) and Ag(II) spectra. The light emitted by the plasma was focused on the input slit of a grating monochromator coupled with a time-resolved optical multichannel analyzer system. Spectral response calibration of the experimental system was made using a deuterium lamp in the wavelength range extending from 200 to 400 nm, and a standard tungsten lamp in the range from 350 to 600 nm. The transition probabilities were obtained using measured branching fractions and available radiative lifetimes of the corresponding states. On the theoretical side, a relativistic Hartree-Fock (HFR) approach, including core-polarization effects, has been used for the calculations. A reasonable agreement theory–experiment has been observed. [less ▲]

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See detailA database of astrophysical interest covering the UV region
Biémont, Emile ULg; Quinet, Pascal ULg

in Journal of Electron Spectroscopy & Related Phenomena (2005), 144-147

Our knowledge of the spectra of the rare-earths is still very poor due to the fragmentary laboratory analyses, on the one hand, and to the complexity of the configurations involving unfilled 4f shells, on ... [more ▼]

Our knowledge of the spectra of the rare-earths is still very poor due to the fragmentary laboratory analyses, on the one hand, and to the complexity of the configurations involving unfilled 4f shells, on the other hand. The database DREAM (Database on Rare Earths at Mons University) contains presently radiative parameters (wavelengths, levels, transition probabilities, Land´e factors) for over 60 000 transitions and is continuously updated. The different tables, which cover not only the UV region, but also the visible and near infrared spectral ranges, which are located on the web page: http://www.umh.ac.be/∼astro/dream.shtml. Up to now, data are tabulated for the following ions : La III, Ce II, Ce III, Pr II, Pr III, Nd II, Nd III, Sm II, Sm III, Eu III, Gd III, Tb III, Dy III, Ho III, Er II, Er III, Tm II, Tm III, Yb II, Yb III, Yb IV, Lu I, Lu II and Lu III. Some information is also provided for Th III. The relevant references (about 40 papers), summarizing and discussing the new experimental and theoretical results obtained during the past few years, are given on this web site. [less ▲]

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See detailRelativistic Hartree-Fock and Dirac-Fock atomic structure calculations in Fr-like ions Ra+, Ac2+Th3+ and U5+
Biémont, Emile ULg; Fivet, V.; Quinet, Pascal ULg

in Journal of Physics B-Atomic Molecular and Optical Physics (2004), 37(20), 4193-4204

A detailed investigation of radiative parameters for electric dipole (El) transitions is presented for the ions Ra II, Ac 111, Th IV and U VI along the francium isoelectronic sequence. The pseudo ... [more ▼]

A detailed investigation of radiative parameters for electric dipole (El) transitions is presented for the ions Ra II, Ac 111, Th IV and U VI along the francium isoelectronic sequence. The pseudo-relativistic Hartree-Fock (BFR) method including core-polarization effects is used for the calculations. Comparisons with multiconfigurational Dirac-Fock (MCDF) calculations show that the most important relativistic effects are taken into account. In view of their importance in nuclear laser spectroscopy, forbidden rates (transitions M1 and E2) in Th IV are also reported in this paper. [less ▲]

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See detailRadiative lifetime and transition probabilities in CdI and CdII
Xu, H. L.; Persson, A.; Svanberg, S. et al

in Physical Review A (2004), 70(4), 1-14

Radiative lifetimes of 11 levels belonging to the 5s5p P-1(1)o 5snd D-3(1,2) (n=6-9) and 5sns S-3(1) (n=7,8) series of Cd I, and of 5 levels of Cd II (i.e., 4d(10)5p P-2(1/2.3/2)o, 4d(10)6s S-2(1/2), and ... [more ▼]

Radiative lifetimes of 11 levels belonging to the 5s5p P-1(1)o 5snd D-3(1,2) (n=6-9) and 5sns S-3(1) (n=7,8) series of Cd I, and of 5 levels of Cd II (i.e., 4d(10)5p P-2(1/2.3/2)o, 4d(10)6s S-2(1/2), and 4d(10)5d D-2(3/2,5/2)) have been measured using the time-resolved laser-induced fluorescence technique. Free neutral and singly ionized cadmium atoms have been generated by laser ablation. Single- or two-step excitation processes were considered to populate the levels under study. Branching fractions of Cd II transitions have been measured by laser-induced breakdown spectroscopy. Transition probabilities and oscillator strengths for Cd I and Cd II spectral lines originating from the above states as well as from the 4d(9)5 s(22)D(3/2,5/2) states of Cd II have been deduced by combining the experimental lifetimes and theoretical branching fractions obtained in multiconfigurational relativistic Hartree-Fock calculations taking core-polarization effects into account. [less ▲]

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See detailOn the importance of an M2 depopulating channel for a KrII metastable state
Biémont, Emile ULg; Derkatch, A.; Lundin, P. et al

in Physical Review Letters (2004), 93(6),

An experimental investigation of the radiative lifetime of the metastable 4s(2)4p(4)(P-3)4d D-4(7/2) level in Kr II shows an unusual situation regarding the importance of an M2 depopulation channel. While ... [more ▼]

An experimental investigation of the radiative lifetime of the metastable 4s(2)4p(4)(P-3)4d D-4(7/2) level in Kr II shows an unusual situation regarding the importance of an M2 depopulation channel. While the first order M1 and E2 channels are expected to contribute in a dominant way to the decay, the experimental result, obtained using a laser probing technique on a stored ion beam, tau=0.57+/-0.03 s, is far too short to be due to these channels according to our relativistic multiconfiguration Dirac-Fock calculation. Only if second order contributions to the decay branches (including essentially the M2 contribution) are taken into account in the calculations could the unexpected short lifetime be explained. [less ▲]

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See detailLande g-factors for experimentally determined energy levels in doubly ionized lanthanides
Quinet, Pascal ULg; Biémont, Emile ULg

in Atomic Data and Nuclear Data Tables (2004), 87(2), 207-230

Lande g-factors have been calculated for over 1500 energy levels of doubly ionized lanthanides (Z = 57-71). Configuration interaction and relativistic effects have been included in the computations using ... [more ▼]

Lande g-factors have been calculated for over 1500 energy levels of doubly ionized lanthanides (Z = 57-71). Configuration interaction and relativistic effects have been included in the computations using the relativistic Hartree-Fock (HFR) technique combined with a least-squares fitting of the Hamiltonian eigenvalues to the observed energy levels. These new results are compared with previous experimental and theoretical values when available. (C) 2004 Elsevier Inc. All rights reserved. [less ▲]

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See detailRadiative lifetimes of Zn I, II excited states
Blagoev, K. B.; Malcheva, G.; Penchev, V. et al

in Physica Scripta (2004), 69(6), 433-440

Radiative lifetimes of excited states of Zn I (3d(10)4sns S-3(1), n = 6-8; 3d(10) 4snd D-3, n = 4-7) and Zn II (3d(10) 4p P-2(1/2.3/2), 4d D-2(3/2,5/2), 3d(10)5S S-2(1/2)) have been measured using a time ... [more ▼]

Radiative lifetimes of excited states of Zn I (3d(10)4sns S-3(1), n = 6-8; 3d(10) 4snd D-3, n = 4-7) and Zn II (3d(10) 4p P-2(1/2.3/2), 4d D-2(3/2,5/2), 3d(10)5S S-2(1/2)) have been measured using a time-resolved laser-induced fluorescence technique. Single- or two-step excitation of atoms and ions produced by laser ablation was employed. The experimental radiative lifetimes have been compared with theoretical results obtained within a multiconfigurational relativistic Hartree-Fock approach taking core-polarization effects into account. [less ▲]

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See detailLifetimes of metastable levels in ArII
Schef, P.; Derkatch, A.; Lundin, P. et al

in European Physical Journal D -- Atoms, Molecules, Clusters & Optical Physics (2004), 29(2), 195-199

We report on a calculation of five lifetimes of metastable levels in Ar II, obtained with a relativistic Hartree-Fock method in which most of the intravalence correlation is represented within a ... [more ▼]

We report on a calculation of five lifetimes of metastable levels in Ar II, obtained with a relativistic Hartree-Fock method in which most of the intravalence correlation is represented within a configuration interaction scheme while core-valence correlation is described by a core-polarization model potential with a core-penetration corrective term. The quality of the calculation has been assessed through an experimental determination of the radiative lifetime of the metastable 3d(4)F(9/2) level. The experiment was performed with a laser probing technique on a stored ion beam at the CRYRING of Stockholm. [less ▲]

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See detailExperimental lifetime determination in neutral praseodymium (Pr I) and neodymium (Nd I)
Biémont, Emile ULg; Quinet, Pascal ULg; Svanberg, S. et al

in Journal of Physics B-Atomic Molecular and Optical Physics (2004), 37(7), 1381-1389

Radiative lifetime measurements have been performed, with a time-resolved laser-induced fluorescence technique, for 18 even-parity levels of Pr I and 15 odd-parity levels of Nd I. The new results are ... [more ▼]

Radiative lifetime measurements have been performed, with a time-resolved laser-induced fluorescence technique, for 18 even-parity levels of Pr I and 15 odd-parity levels of Nd I. The new results are compared with the few experimental data available in the literature and good agreement is found. However, fragmentary knowledge of the spectra prevents reliable calculation of branching fractions and calls for additional laboratory efforts in order to provide the astrophysicists with reliable transition probabilities needed for investigating the magnetic fields in chemically peculiar stars. [less ▲]

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See detailRadiative lifetimes of Cd I and Cd II excited states
Xu, H.; Persson, A.; Svanberg, S. et al

Conference (2004)

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See detailL'astronomie en Europe à la fin du XVIIIè siècle (1789-1802)
Biémont, Emile ULg

Conference (2004)

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See detailAstronomes célèbres et astronomes moins connus ... (4) Bailly
Biémont, Emile ULg

in Galactée (2004), 40

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See detailAstronomes célèbres et astronomes moins connus ... (5) Hubble
Biémont, Emile ULg

in Galactée (2004), 43

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See detailTime-resolved laser-induced fluorescence lifetime measurements and relativistic Hartree-Fock calculations of transition probabilities in SmII
Xu, H. L.; Svanberg, S.; Quinet, Pascal ULg et al

in Journal of Physics B-Atomic Molecular and Optical Physics (2003), 36(24), 4773-4787

Radiative lifetime measurements were performed with time-resolved laser-induced fluorescence techniques for 47 levels of the astrophysically important ion Sm1+ over the energy range 21000-36 000 cm(-1 ... [more ▼]

Radiative lifetime measurements were performed with time-resolved laser-induced fluorescence techniques for 47 levels of the astrophysically important ion Sm1+ over the energy range 21000-36 000 cm(-1). The new results have been compared with previous measurements but also with theoretical calculations taking configuration interactions and core-polarization effects into account, and a satisfying agreement has been found for many levels of this complex ion. New calculated transition probabilities are deduced from the experimental lifetimes and from the theoretical branching fractions for 162 transitions of astrophysical interest. These results will help astrophysicists in the quantitative investigation of the chemical composition of CP stars. [less ▲]

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