The Herbig Ae SB2 System HD 104237

TL;DR

This study analyzes the binary system HD 104237, providing updated orbital data, detailed elemental abundances for both stars, and comparing their spectra with other Herbig Ae stars to understand their properties.

Contribution

It offers new orbital parameters, detailed abundance analyses for both stars, and spectral comparisons, enhancing understanding of Herbig Ae star systems.

Findings

Significant orbital change from previous data.

Abundances mostly near solar, with lithium marginally enhanced in primary.

Emission spectrum typical of Herbig Ae stars.

Abstract

The double-lined spectroscopic binary HD 104237 (DX Cha) is part of a complex system of some half-dozen nearby young stars. We report a significant change from an orbit for the SB2 system derived from 1999-2000 observations. We obtain abundances from the primary and secondary spectra. The abundance analysis uses both detailed spectral synthesis and determinations based on equivalent widths of weak absorption lines with W(lambda) typically < 25 mA. Abundances are derived for 25 elements in the primary, and 17 elements in the secondary. Apart from lithium and zirconium, abundances do not depart significantly from solar. Lithium may be marginally enhanced with respect to the meteoritic value in the primary. It somewhat depleted in the secondary. The emission-line spectrum is typical of Herbig Ae stars. We compare and contrast the spectra of the HD 104237 primary and two other Herbig Ae stars with low v.sin(i), HD 101412 and HD 190073.