The absorption and emission spectrum of the magnetic Herbig Ae star HD 190073

TL;DR

This study analyzes the absorption and emission spectra of the magnetic Herbig Ae star HD 190073, providing detailed measurements and discussing the implications for the star's atmospheric conditions, with a focus on spectral line features.

Contribution

It offers the first detailed quantitative measurements of over 60 emission lines and discusses the spectral features without modeling, highlighting the star's complex atmospheric regions.

Findings

Most elemental abundances are close to solar values.

Emission lines vary significantly in width, indicating diverse formation regions.

Presence of emission lines suggests complex, multi-region stellar atmospheres.

Abstract

We determine abundances from the absorption spectrum of the magnetic Herbig Ae star HD 190073 (V1295 Aql). The observations are primarily from HARPS spectra obtained at a single epoch. We accept arguments that the presence of numerous emission lines does not vitiate a classical abundance analysis, though it likely reduces the achievable accuracy. Most abundances are closely solar, but several elements show departures of a factor of two to three, as an earlier study has also shown. We present quantitative measurements of more than 60 emission lines, peak intensities, equivalent widths, and FWHM's. The latter range from over 200 km/s (H-alpha, He D3) down to 10--20 km/s (forbidden lines). Metallic emission lines have intermediate widths. We eschew modeling, and content ourselves with a presentation of the observations a successful model must explain. Low-excitation features such as the Na I D-lines and [O I] appear with He I D3, suggesting proximate regions with widely differing Te and Ne as found in the solar chromosphere. The [O I] and [Ca II] lines show sharp, violet-shifted features. Additionally, [Fe II] lines appear to be weakly present in emission.