Spectro-interferometric observations of interacting massive stars with VEGA/CHARA

Daniel Bonneau (1) , Olivier Chesneau (1) , Denis Mourard (1) , Philippe Stee (1)

1 FIZEAU - Laboratoire Hippolyte Fizeau

We obtained spectro-interferometric observations in the visible of $\beta$~Lyrae and $\upsilon$~Sgr using the instrument VEGA of the CHARA interferometric array. For $\beta$~Lyrae, the dispersed fringe visibilities and differential phases were obtained in spectral regions containing the H$\alpha$ and HeI 6678 lines and the H$\beta$ and HeI 4921 lines. Whereas the source is unresolved in the continuum, the source of the emission lines is resolved and the photocenter of the bulk of the H$\alpha$ emission exhibits offsets correlated with the orbital phase. For $\upsilon$~Sgr, both the continuum and H$\alpha$ sources are resolved, but no clear binary signal is detected. The differential phase shift across the line reveals that the bulk of the H$\alpha$ emission is clearly offset from the primary.

Domaines: Astrophysique stellaire et solaire [astro-ph.SR]; Astrophysique stellaire et solaire [astro-ph.SR]

Daniel Bonneau, Olivier Chesneau, Denis Mourard, Philippe Stee. Spectro-interferometric observations of interacting massive stars with VEGA/CHARA. 2010. ⟨hal-00432349⟩