Study of environment and photosphere of 51 Oph
The main objective of this work is to improve our understanding of young fast-rotating stars evolving from the Herbig Ae/Be class to the Vega-like one. We observed with the VEGA instrument on CHARA one object so-called 51 Oph that is probably in such an evolutionary phase, allowing us to measure a mean stellar radius for […]
An interferometric journey around massive stars
Since the construction in the late nineties of modern facilities such as the VLTI or CHARA, interferometry became a key technique to probe massive stars and their often-complex circumstellar environments. Over the last decade, the development of a new generation of beam combiners for these facilities enabled major breakthroughs in the understanding of the formation […]
The impact of the rotation on the surface brightness of early-type stars
The surface brightness colors (SBC) relation is a very important tool to derive the distance of extragalactic eclipsing binaries. However, for early-type stars, this SBC relation is critically affected by the stellar environment (wind, circumstellar disk, etc…) and/or by the fast rotation. We calculated 6 models based on the code of Domiciano de Souza et […]
Interferometry of massive stars: the next step
We present some new and interesting results on the complementarity between asteroseismology and interferometry, the detection of non-radial pulsations in massive stars and the possibility for evidencing differential rotation on the surface of Bn stars. We also discuss the curretn interferometric facilities, namely the Very Large Telescope Interferometer (VLTI)/AMBER, VLTI/MIDI, VLTI/PIONIER within the European Southern […]
Resolving the dusty circumstellar environment of the A[e] supergiant HD 62623 with the VLTI/MIDI
HD 62623 is one of the very few A-type supergiants showing the B[e] phenomenon. We studied the geometry of its circumstellar envelope in the mid-infrared using the VLTI/MIDI instrument. Using the radiative transfer code MC3D, we managed to model it as a dusty disk with an inner radius of 3.85 AU, an inclination angle of […]
Imaging “Pinwheel” nebulae with optical long-baseline interferometry
Dusty Wolf-Rayet stars are few but remarkable in terms of dust production rates (up to Ṁ = 10<SUP>-6</SUP> M<SUB>solar</SUB>/yr). Infrared excesses associated to mass-loss are found in the sub-types WC8 and WC9. Few WC9d stars are hosting a “pinwheel” nebula, indirect evidence of a companion star around the primary. While few other WC9d stars have […]
Images of unclassified and supergiant B[e] stars disks with interferometry
B[e] stars are among the most peculiar objects in the sky. This spectral type, characterised by allowed and forbidden emission lines, and a large infrared excess, does not represent an homogenous class of objects, but instead, a mix of stellar bodies seen in all evolutionary status. Among them, one can find Herbig stars, planetary nebulae […]