|
European Astronomical Society
|
|
|
|
|
|
|
EAS Job Directory
Find Jobs
| Efficient data processing techniques for high-angular resolution images in the visible. | Closing date: 2017-04-15
Contact: Benoit Neichel |
| High-angular resolution imaging at visible wavelengths is one of the main challenge for the next generation ground-based instrumentation, with applications both for astronomy (Hubble Space Telescope replacement) or defense (imaging low-orbit satellites). At the heart of those instruments, Adaptive Optics [AO] provides diffraction-limited images. | | ▸ more | Current AO systems are however, mostly limited to corrections delivered in the Near Infra-Red. Pushing the corrections toward visible wavelengths, providing diffraction-limited images on medium field-of-view (15? to 30?), and with reasonable sky coverage would represent a unique science niche for 8m telescopes in the 30/40m telescope era. However, pushing AO wide-field correction toward visible wavelengths requires new observational strategy and challenging development in concepts and technologies. And in particular, an optimized and efficient post-processing stage is mandatory in order to reduce significantly the residual optical aberrations and to reach the ultimate performance. The PhD work proposed will be at the center of these developments.
Being able to capture short-exposure science images would allow retrieving the ultimate performance by compensating the residual turbulence aberrations that would not be compensated by the AO system. The standard methods for data processing, like deconvolution, become a challenge when applied to short exposures images. At visible wavelengths, the AO correction is varying quickly in time (from one frame to the next) and spatially (within a single image). This fundamental change calls for revisiting the entire process of impulse response (or PSF) reconstruction, and associated image processing. New methods, based on existing ones like ?speckle imaging/interferometry?, ?deconvolution by Wave-Front Sensing?, of ?myopic deconvolution? will have to be explored. The main goal of this PhD is then to propose new approaches for data processing, including the most recent development in AO and in visible wavelengths imaging. The work will be divided in 4 steps:
(i) Theoretical comparison of current methods for short and long exposure images
(ii) Proposing innovative methods for short exposure processing, including information provided
by the AO real-time instrument.
(iii) Application of the methods to on-sky observations based on the ODISEE bench located at the
?Observatoire de la Côte d?Azur?.
(iv) Application of the methods to the design and definition of a new instrument for astronomical 8m telescope
The student will be at the center of a rich scientific context, at the interface between instrumentation, detectors physics and astronomical needs, sharing work and results with an international team. We expect that this young researcher will be an excellent way to disseminate the results of her/his research in the international community and reinforce the collaboration between the institutions involved in this project.
|
More resources
Links to other job lists
|
