Observations of AraS. Lacour & X. Haubois

Be stars -> Hot main sequence stars with :

• Emission in H• Circumstellar shell• Rotation• Non radial pulsations• Flares : Mass Ejection ?

Reduction…

UV plane and visibilities

Without calibration With calibration

But the information is in the phase! (differential)

• 0.3 rad rms 16 degree rms : The closure phase measurements are very noisy

• The differential phase is great!