PERSEE: experimental results on the cophased nulling bench
2010
Nulling interferometry is still a promising method to characterize spectra of exoplanets. One of the main issues
is to cophase at a nanometric level each arm despite satellite disturbances. The bench PERSEE aims to prove
the feasibility of that technique for spaceborne missions. After a short description of PERSEE, we will first
present the results obtained in a simplified configuration: we have cophased down to 0.22 nm rms in optical
path difference (OPD) and 60 mas rms in tip/tilt, and have obtained a monochromatic null of 3 · 10 -5 stabilized
at 3•10 -6 . The goal of 1 nm with additional typical satellite disturbances requires the use of an optimal
control law; that is why we elaborated a dedicated Kalman filter. Simulations and experiments show a good
rejection of disturbances. Performance of the bench should be enhanced by using a Kalman control law, and we
should be able to reach the desired nanometric stability. Following, we will present the first results of the final
polychromatic configuration, which includes an achromatic phase shifter, perturbators and optical delay lines.
As a conclusion, we give the first more general lessons we have already learned from this experiment, both at
system and component levels for a future space mission.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
16
References
6
Citations
NaN
KQI