ON THE ORIGIN OF EXOZODIACAL DUST
“EXOZODI” : an ANR-funded project [2011-2014]

  J.-C. Augereau

 
 

Scientific Background:


When observing an extrasolar planetary system, the most luminous component after the star itself is generally the light scattered and/or thermally emitted by a population of micron-sized dust grains. These grains are expected to be continuously replenished by the collisions and evaporation of larger bodies just as in our solar zodiacal cloud. Exozodiacal clouds (exozodis) must therefore be seriously taken into account when attempting to directly image faint Earth-like planets.


Exozodis remained elusive until the first near-infrared interferometric detection in 2006 by our team around the star Vega. The origin of exozodiacal dust is still an unresolved issue. However, the richness of this subject, its connection to the general dynamical evolution of planetary systems, in particular in the innermost potentially habitable regions, makes it a fast emerging research field.


Main goals of the EXOZODI project:

  1. i)Carry out the first ever statistical near-IR interferometric survey of exozodiacal disks in both hemispheres thanks to one instrument in California (FLUOR at CHARA), and an other in Chile (PIONIER at the VLTI);

  2. ii)Complete among the first dynamical simulations for the detected exozodis, thereby better assessing the origin of the exozodiacal disks, and in particular, its connection with the presence of planets and an external Kuiper-like Belt;

  3. iii)Realize a qualitative step forward in debris disks modeling, by merging the statistical and dynamical approaches and develop the first models able to investigate the coupled effects of collisions and dynamics.

Exozodis detected by our team:

  1. Vega (2006)

  2. τ Ceti (2007)

  3. ζ Aql (2008)

  4. Fomalhaut (2009)

  5. More to come ...

Post-Doc and PhD Positions in the context of the EXOZODI Project:
informal inquiries should be sent to J.-C. Augereau
[augereau at ujf-grenoble.fr]