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1. Hypertelescopes and exo-planetary coronagraphy Antoine Labeyrie ( Collège de France & LISE)
2. Detecting auroral activity on exo-Jupiters Visible, UV: narrow emission lines detectable ?
with un-resolved interferometry ( 100m hypertelescope)
With resolved interferometry ( 100 km hypertelescope “Exo-Earth Imager”)
Radio: hypertelescope imaging and coronagraphy also applicable, in space
3. Towards an Exo-Earth Imager : 100 km hypertelescope with coronagraph. Goals:
resolved image of an Earth at 3 pc in 30 mn,
search colored spots of photosynthetic life,
free-flyer ’s array : 150 km size,
150 3 m mirrors.
4. What ’s a hypertelescope ? A multi-element imaging interferometric array.
Uses densified-pupil imaging to provide direct images.
Usable for coronagraphy at focus.
5. Densify the pupil, but preserve the apertures pattern. Principle of the hypertelescope (Labeyrie A&A, 1996)
6. Optical scheme: on-axis source
7. Optical scheme: off-axis source
8. Field of a periodic & fully densified hypertelescope:
9. Hypertelescope with coronagraph Coronagraph fits like on conventional telescope
The densified exit pupil behaves like a classical pupil
10. Hypertelescope proposed for DARWIN and TPF (Boccaletti et al., Icarus, May 2000)
11. hypertelescope element (artist concept by Boeing/SVS)
12. Hypertelescope proposed for DARWIN and TPF: focal combiner and densifier
13. Removing coronagraphic residues
14. Multi-stage stellar coronagraphyfor detecting planets in the visible Residual stellar speckles phased ( analyzer not shown)
Interference peak in the far field, masked
Cleaned relayed image of planet(s)
Cascadable until few stellar photons left
15. Feasibility of a “Neutron Star Imager” Size: 105 - 106 kilometers to resolve the 20 km source.
8-meter mirrors,
and combiner of similar size, for diffractive matching.
Paraboloïdal primary locus, for manageable combiner size.
Internal laser metrology + global pointing for image acquisition in HOF ( 10 mas) and ZOF (nanoseconds)
Many photons/resel/s on Crab pulsar, but too few on ordinary stars.
16. Coronagraphy of binary star within l/d
17. Mosaïc of high resolution images
coro 1 résidue : ghost image of star in each image multiple channels of two-stage coronography
18. Ground versions:hypertelescope image at VLTI Off axis example