VizieR Online Data Catalog: Abundances in cool metal-polluted white dwarfs (Blouin, 2020)
Abstract
Our sample is identical to the Sloan Digital Sky Survey (SDSS) sample analysed in Hollands et al. (2017MNRAS.467.4970H, Cat. J/MNRAS/467/4970), but we excluded the 27 known magnetic objects. We decided to exclude magnetic DZs as a description of line broadening under strong magnetic fields (B>1MG) and high helium densities is not yet available. From the results of Hollands et al. (2017MNRAS.467.4970H, Cat. J/MNRAS/467/4970), we are confident that excluding magnetic objects will not induce a bias in the average abundances of our sample. We also excluded SDSS J122656.39+293643.9 since its SDSS spectrum is so noisy that we are unable to extract any meaningful abundances from it, as well as SDSS J051212.78-050503.4 and SDSS J082303.82+054656.1, for which no SDSS spectrum is available. In total, the sample analysed here contains 201 objects. Their observational properties (ugriz photometry and Gaia DR2 distances) are listed in Table 1.
The model atmosphere code used in this paper is described at length in Blouin et al. (2018ApJ...863..184B, 2018ApJ...867..161B). Of particular importance for this work are the unified line profiles that are used to retrieve the photospheric abundances of Ca and Mg. We computed a six-dimensional grid of model atmospheres with Teff varying from 4000 to 9000K in steps of 500K, logg from 7.0 to 9.0 in steps of 0.5dex, logH/He from -5 to -2 in steps of 1dex, logCa/He from -11 to -7 in steps of 0.5dex, logMg/Ca from 0.24 to 2.24 in steps of 0.5dex, and logFe/Ca from 0.16 to 2.16 in steps of 0.5dex. The atmospheric parameters found with the fitting procedure are listed in Table 2. (2 data files).- Publication:
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VizieR Online Data Catalog
- Pub Date:
- June 2023
- Bibcode:
- 2023yCat..74961881B
- Keywords:
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- Stars: white dwarf;
- Abundances: peculiar;
- Effective temperatures;
- Stars: masses;
- Stars: distances;
- Stars: distances;
- Photometry: ugriz