Observatoire de Paris Institut national de recherche scientifique français Univerité Pierre et Marie Curie Université Paris Diderot - Paris 7

"Interacting binaries at very high angular resolution" and "Cophasing the next generation of optical interferometers."

Thursday 9 February 2012, by Nicolas Blind (Institut de Planétologie et d'Astrophysique de Grenoble)

Thursday 16 February 2012 à 11h00 , Lieu : Salle de confĂ©rence du bât. 17

Interacting binaries are systems in which mass is transferred from a giant component to a more compact companion. These systems present numerous properties relevant to many astrophysical objects (e.g. accretion disks), making them excellent laboratories to study a large spectrum of physical processes. The breakthrough for studying these systems promises to come from optical interferometry, allowing to zoom in their most inner regions.

However, optical interferometers highly suffer of the atmospheric turbulence. Similarly to Adaptive Optics for single-dish telescopes, the development of external Fringe Trackers is critical to cophase future interferometers combining 4 to 6 telescopes. Fringe Trackers will reveal the full potential of interferometry by increasing the sensitivity up to a factor of 1000 and by allowing model-independent spectro-imaging.

This talk will be split in to parts. First, I will focus on interacting binaries with the particular system SS Leporis observed at the VLT Interferometer. Then, I will come to Fringe Tracking issues and will present several studies having led to "POPS", a 2nd generation Fringe Tracker concept for the VLTI.

N.B. Seminar in french