The Belgian repository of fundamental atomic data and stellar spectra (BRASS). I. Cross-matching atomic databases of astrophysical interest

Abstract

Fundamental atomic parameters, such as oscillator strengths, play a key role in modelling and understanding the chemical composition of stars in the universe. Despite the significant work underway to produce these parameters for many astrophysically important ions, uncertainties in these parameters remain large and can propagate throughout the entire field of astronomy. The Belgian repository of fundamental atomic data and stellar spectra (BRASS) aims to provide the largest systematic and homogeneous quality assessment of atomic data to date in terms of wavelength, atomic and stellar parameter coverage. To prepare for it, we first compiled multiple literature occurrences of many individual atomic transitions, from several atomic databases of astrophysical interest, and assessed their agreement. Several atomic repositories were searched and their data retrieved and formatted in a consistent manner. Data entries from all repositories were cross-matched against our initial BRASS atomic line list to find multiple occurrences of the same transition. Where possible we used a non-parametric cross-match depending only on electronic configurations and total angular momentum values. We also checked for duplicate entries of the same physical transition, within each retrieved repository, using the non-parametric cross-match. We report the cross-matched transitions for each repository and compare their fundamental atomic parameters. We find differences in log(gf) values of up to 2 dex or more. We also find and report that ~2% of our line list and Vienna Atomic Line Database retrievals are composed of duplicate transitions. Finally we provide a number of examples of atomic spectral lines with different log(gf) values, and discuss the impact of these uncertain log(gf) values on quantitative spectroscopy. All cross-matched atomic data and duplicate transitions are available to download at brass.sdf.org.

arXiv comment18 pages, 12 figures, 9 tables. Accepted for publication in A&A

References in corpus (20)

• The chemical composition of the Sun
• The Gaia mission
• Solar Chemical Abundances Determined with a CO5BOLD 3D Model Atmosphere
• HERMES: a high-resolution fibre-fed spectrograph for the Mercator telescope
• The elemental composition of the Sun II. The iron group elements Sc to Ni
• The photospheric solar oxygen project: I. Abundance analysis of atomic lines and influence of atmospheric models
• The elemental composition of the Sun I. The intermediate mass elements Na to Ca
• The elemental composition of the Sun III. The heavy elements Cu to Th
• Improved Ti II log(gf) Values and Abundance Determinations in the Photospheres of the Metal-Poor Star HD 84937
• Atomic and Molecular Data for Optical Stellar Spectroscopy
• Quantitative Spectroscopy of BA-type Supergiants
• Fe I Oscillator Strengths for the Gaia-ESO Survey
• An accurate and self-consistent chemical abundance catalogue for the APOGEE/Kepler sample
• The spectrum of Fe II
• Fe I oscillator strengths for transitions from high-lying odd-parity levels
• Stellar laboratories IV. New Ga IV, Ga V, and Ga VI oscillator strengths and the gallium abundance in the hot white dwarfs G191-B2B and RE0503-289
• Laboratory oscillator strengths of Sc I in the near-infrared region for astrophysical applications
• New Mn II energy levels from STIS-HST spectrum of the HgMn star HD 175640
• SpectroWeb: Oscillator Strength Measurements of Atomic Absorption Lines in the Sun and Procyon
• Experimental radiative lifetimes for highly excited states and calculated oscillator strengths for lines of astrophysical interest in singly ionized cobalt (Co II)

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