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arXiv · astro-ph/0410366

Spectral disentangling of the triple system DG Leo: orbits and chemical composition

Abstract

DG Leo is a spectroscopic triple system composed by 3 stars of late-A spectral type, one of which was suggested to be a delta Scuti star. Seven nights of observations at high spectral and high time resolution at the Observatoire de Haute-Provence with the ELODIE spectrograph were used to obtain the component spectra by applying a Fourier transform spectral disentangling technique. Comparing these with synthetic spectra, the stellar fundamental parameters (effective temperature, surface gravity, projected rotation velocity and chemical composition) are derived. The inner binary consists of two Am components, at least one of which is not yet rotating synchronously at the orbital period though the orbit is a circular one. The distant third component is confirmed to be a delta Scuti star with normal chemical composition.

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Y. Fremat, P. Lampens, H. Hensberge. 2004-10-15. Spectral disentangling of the triple system DG Leo: orbits and chemical composition. https://doi.org/10.1111/j.1365-2966.2004.08478.x

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