Current Status and Developments of the Atomic Database on Rare-Earths at Mons University (DREAM)

Abstract

<jats:p>The main purpose of the Database on Rare Earths At Mons University (DREAM) is to provide the scientific community with updated spectroscopic parameters related to lanthanide atoms (Z = 57–71) in their lowest ionization stages. The radiative parameters (oscillator strengths and transitions probabilities) listed in the database have been obtained over the past 20 years by the Atomic Physics and Astrophysics group of Mons University, Belgium, thanks to a systematic and extensive use of the pseudo-relativistic Hartree-Fock (HFR) method modified for taking core-polarization and core-penetration effects into account. Most of these theoretical results have been validated by the good agreement obtained when comparing computed radiative lifetimes and accurate experimental values measured by the time-resolved laser-induced fluorescence technique. In the present paper, we report on the current status and developments of the database that gathers radiative parameters for more than 72,000 spectral lines in neutral, singly-, doubly-, and triply-ionized lanthanides.</jats:p>

Multiconfiguration Dirac–Hartree–Fock radiative parameters for emission lines in Ce ii–ivions and cerium opacity calculations for kilonovae

“…The wavelengths, transition probabilities and oscillator strengths were then computed for the spectral lines involving all the Ce II atomic states obtained in the CV1 model. When comparing these results with the data taken from the DREAM database (Quinet & Palmeri 2020), we found a good overall agreement, i.e. within 5% for the wavelengths and within 30% for the transition rates.…”

“…In Figures 14, 15 and 16, we show the expansion opacities calculated by using transition rates of Ce II, Ce III, and Ce IV, respectively. The blue lines correspond to the results deduced from the best atomic data computed in the present paper, while the red lines in Figures 14 and 15 display the results obtained using the radiative parameters listed in the DREAM database (Quinet and Palmeri 2020). When looking at Figure 14 it can be clearly observed that, for Ce II, the behaviour of opacity is similar whether we use our atomic data or those taken from DREAM, both curves having a maximum at about 4400 Å (4355 Å using our data and 4395 Å using DREAM).…”

“…In Table 4, we compare the radiative transition probabilities obtained using our CV2 model with those listed in the DREAM database (Quinet & Palmeri 2020) for the 50 most intense lines (gA > 10 7 s −1 ). A rather good overall agreement is observed when comparing both sets of data, the mean ratio gA T his work /gADREAM being found to be equal to 0.90 ± 0.56.…”

“…In order to allow a wide dissemination of the new results obtained, we created the DREAM database (Database on Rare-Earths At Mons University) 1 which currently contains spectroscopic information for more than 72000 spectral lines belonging to neutral, singly-, doubly-, and trebly-ionized lanthanide atoms. These investigations gave rise to about fifty publications, the summary of which is given in a recent review paper (Quinet & Palmeri 2020).…”

A Decade with VAMDC: Results and Ambitions

“…The Database of Rare Earths At Mons University (DREAM) contains information concerning the radiative parameters (wavelengths, transition probabilities and oscillator strengths) for more than 72,000 spectral lines belonging to the lower ionisation stages of lanthanide elements (Z = 57 to 71), from neutral to triply ionised species. This database, originally created by Biémont et al [45] and recently updated by Quinet and Palmeri [39], is hosted by Mons University (http://hosting.umons.ac. be/html/agif/databases/dream.html).…”