32 results on '"Lucie Leboulleux"'
Search Results
2. Connecting the astronomical testbed community -- the CAOTIC project: Optimized teaching methods for software version control concepts
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Iva Laginja, Pablo Rodríguez Robles, Kevin Barjot, Lucie Leboulleux, Rebecca M. Jensen-Clem, Keira J. Brooks, Christopher Moriarty, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France
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Physics - Instrumentation and Detectors ,FOS: Physical sciences ,[PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det] ,Instrumentation and Detectors (physics.ins-det) ,Astrophysics - Instrumentation and Methods for Astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,[PHYS.PHYS.PHYS-GEN-PH]Physics [physics]/Physics [physics]/General Physics [physics.gen-ph] ,Optics (physics.optics) ,Physics - Optics - Abstract
Laboratory testbeds are an integral part of conducting research and developing technology for high-contrast imaging and extreme adaptive optics. There are a number of laboratory groups around the world that use and develop resources that are imminently required for their operations, such as software and hardware controls. The CAOTIC (Community of Adaptive OpTics and hIgh Contrast testbeds) project is aimed to be a platform for this community to connect, share information, and exchange resources in order to conduct more efficient research in astronomical instrumentation, while also encouraging best practices and strengthening cross-team connections. In these proceedings, we present the goals of the CAOTIC project, our new website, and we focus in particular on a new approach to teaching version control to scientists, which is a cornerstone of successful collaborations in astronomical instrumentation., 15 pages, 6 figures, 2 tables; SPIE proceedings Astronomical Telescopes + Instrumentation 2022, 12185-119
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- 2022
3. Imageur à haut contraste pour les télescopes à ouverture complexe (HICAT) : 8. Démonstration de Dark Zone avec boucles fermées simultanées à bas ordres
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Rémi Soummer, Emiel H. Por, Raphaël Pourcelot, Susan F. Redmond, Iva Laginja, Scott D. Will, Marshall D. Perrin, Laurent Pueyo, Ananya Sahoo, Peter Petrone, Keira J. Brooks, Rachel Fox, Alex Klein, Bryony Nickson, Thomas Comeau, Marc Ferrari, Rob Gontrum, John Hagopian, Lucie Leboulleux, Daniel Leongomez, Joe Lugten, Laurent M. Mugnier, Mamadou N'Diaye, Meiji Nguyen, James Noss, Jean-François Sauvage, Nathan Scott, Anand Sivaramakrishnan, Hari B. Subedi, Sam Weinstock, Space Telescope Science Institute (STSci), Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA), Department of Mechanical and Aerospace Engineering [Princeton] (MAE), Princeton University, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Observatoire de Paris, Université Paris sciences et lettres (PSL), NASA Goddard Space Flight Center (GSFC), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Advanced Nanophotonics, DOTA, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, DOTA, ONERA [Salon], ONERA, Johns Hopkins University (JHU), and NASA
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GOMaP ,[PHYS]Physics [physics] ,[SPI]Engineering Sciences [physics] ,LUVEx ,OPTIQUE ACTIVE ,Coronagraphy high-contrast GOMaP LUVEx LUVOIR ,high-contrast ,LUVOIR ,Coronagraphy ,EXOPLANETE - Abstract
International audience; We present recent laboratory results demonstrating high-contrast coronagraphy for the future space-based large IR/Optical/Ultraviolet telescope recommended by the Decadal Survey. The High-contrast Imager for Complex Aperture Telescopes (HiCAT) testbed aims to implement a system-level hardware demonstration for segmented aperture coronagraphs with wavefront control. The telescope hardware simulator employs a segmented deformable mirror with 37 hexagonal segments that can be controlled in piston, tip, and tilt. In addition, two continuous deformable mirrors are used for high-order wavefront sensing and control. The low-order sensing subsystem includes a dedicated tip-tilt stage, a coronagraphic target acquisition camera, and a Zernike wavefront sensor that is used to measure and correct low-order aberration drifts. We explore the performance of a segmented aperture coronagraph both in "static" operations (limited by natural drifts and instabilities) and in "dynamic" operations (in the presence of artificial wavefront drifts added to the deformable mirrors), and discuss the estimation and control strategies used to reach and maintain the dark-zone contrast using our low-order wavefront sensing and control. We summarize experimental results that quantify the performance of the testbed in terms of contrast, inner/outer working angle and bandpass, and analyze limiting factors.
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- 2022
4. Redundant apodization for direct imaging of exoplanets I: Robustness to primary mirror segmentation-induced errors outside the segment diffraction limit
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Lucie Leboulleux, Alexis Carlotti, and Mamadou N’Diaye
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Space and Planetary Science ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) - Abstract
Direct imaging and spectroscopy of Earth-like planets and young Jupiters require contrasts up to 10^6-10^10 at angular separations of a few dozen milliarcseconds. To achieve this goal, one of the most promising approaches consists of using large segmented primary mirror telescopes with coronagraphic instruments. However, coronagraphs are highly sensitive to wavefront errors. The segmentation itself is responsible for phasing errors and segment vibrations to be controlled at a subnanometric accuracy. We propose an innovative method for a coronagraph design that allows a consequent relaxation of the segment phasing constraints for low segment-count mirrors and generates an instrument that is more robust to segment-level wavefront errors. It is based on an optimization of the coronagraph that includes a segment-level apodization. This is repeated over the pupil to match the segmentation redundancy and improves the contrast stability beyond the minimum separation set by the single-segment diffraction limit. We validate this method on a GMT-like pupil for two coronagraph types: apodized pupil Lyot coronagraphs (APLC) and apodizing phase plate coronagraphs (APP). For the APLC, redundant apodization enables releasing the piston phasing constraints by a factor of 5 to 20 compared to classical designs. For the APP, the contrast remains almost constant up to 1 radian RMS of the phasing errors. We also show that redundant apodizations increase the robustness of the coronagraph to segment tip-tilt errors, as well as to missing segments. This method cannot be applied to higher-segment count mirrors such as the ELT or the TMT, but it is particularly suitable for low segment-count mirrors (fewer than 20 segments) such as the GMT aperture. These mirrors aim for high-contrast imaging of debris disks or exoplanets down to 100 mas., 11 pages, 17 figures
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- 2022
5. Maria Mitchell
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Lucie Leboulleux and Université Grenoble Alpes (UGA)
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[SPI]Engineering Sciences [physics] - Abstract
Maria Mitchell was a pioneer in many aspects: first observer of a comet with a telescope, she received the Gold Medal from the King of Denmark and became the first female astronomer and astronomy professor in the United States of America. But she also got involved in feminism, participating in the foundation of the Association for the Advancement of Women in 1873 as well as promoting the access to higher education for women and their inclusion in science.
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- 2021
6. High-contrast imager for complex aperture telescopes (HiCAT): 7. Dark zone demonstration with fully segmented aperture coronagraph
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Scott D. Will, James Noss, Kelsey Glazer, Jaret Prothro, Iva Laginja, Gregory R. Brady, Hari B. Subedi, Peter Petrone, Raphaël Pourcelot, Evelyn McChesney, Laurent Mugnier, Sam Weinstock, Marshall D. Perrin, Heather Olszewski, Ron Shiri, Susan M. Redmond, John G. Hagopian, Matthew Maclay, Bryony Nickson, Leonid Pogorelyuk, Lucie Leboulleux, Meiji Nguyen, Yinzi Xin, Emiel H. Por, Rémi Soummer, Ananya Sahoo, Mamadou N'Diaye, Anand Sivaramakrishnan, Julia Fowler, Nathan Scott, Maggie Kautz, Rebecca Zhang, Laurent Pueyo, Théo Jolivet, Rob Gontrum, Keira Brooks, Jean-François Sauvage, and Thomas Comeau
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Physics ,Wavefront ,business.industry ,Aperture ,Astrophysics::Instrumentation and Methods for Astrophysics ,Wavefront sensor ,Deformable mirror ,law.invention ,Telescope ,Tilt (optics) ,Optics ,law ,Piston (optics) ,Astrophysics::Earth and Planetary Astrophysics ,business ,Coronagraph - Abstract
We present recent laboratory results demonstrating high-contrast coronagraphy for future space-based large segmented telescopes such as the Large UV, Optical, IR telescope (LUVOIR) mission concept studied by NASA. The High-contrast Imager for Complex Aperture Telescopes (HiCAT) testbed aims to implement a system-level hardware demonstration for segmented aperture coronagraphs with wavefront control. The telescope hardware simulator employs a segmented deformable mirror with 36 hexagonal segments that can be controlled in piston, tip, and tilt. In addition, two continuous deformable mirrors are used for high-order wavefront sensing and control. The low-order sensing subsystem includes a dedicated tip-tilt stage, a coronagraphic target acquisition camera, and a Zernike wavefront sensor that is used to measure low-order aberration drifts. We explore the performance of a segmented aperture coronagraph both in “static” operations (limited by natural drifts and instabilities) and in “dynamic” operations (in the presence of artificial wavefront drifts added to the deformable mirrors), and discuss the estimation and control strategies used to reach and maintain the dark zone contrast. We summarize experimental results that quantify the performance of the testbed in terms of contrast, inner/outer working angle and bandpass, and analyze limiting factors by comparing against our end-to-end models.
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- 2021
7. Caroline Émilie « Lili » Bleeker
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Lucie Leboulleux, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)
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[SPI]Engineering Sciences [physics] - Abstract
International audience; Caroline Émilie « Lili » Bleeker était une physicienne et auto-entrepreneuse néerlandaise. Après un doctorat sur les spectres des alcaloïdes, elle monte la première entreprise néerlandaise de production de matériel et d’instruments optiques. Elle signe notamment avec Frederik Zernike le brevet sur le microscope à contraste de phase, pour lequel le physicien obtient le prix Nobel de Physique en 1953. Elle se démarque également pour son engagement contre le nazisme lors de la Seconde Guerre Mondiale.
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- 2020
8. Changing the color of textiles with realistic visual rendering.
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Mathieu Hébert, Lambert Henckens, Justine Barbier, Lucie Leboulleux, Marine Page, Lucie Roujas, and Anthony Cazier
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- 2015
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9. Cecilia Helena Payne-Gaposchkin
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Lucie Leboulleux
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- 2020
10. Predicting contrast sensitivity to segmented aperture misalignment modes for the HiCAT testbed
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Keira Brooks, Scott D. Will, Iva Laginja, J. Scott Knight, Jean-François Sauvage, Lucie Leboulleux, Laurent Pueyo, Laura E. Coyle, Laurent M. Mugnier, Marshall D. Perrin, Julia Fowler, James Noss, Rémi Soummer, DOTA, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, Space Telescope Science Institute (STSci), Observatoire de Paris, Université Paris sciences et lettres (PSL), Ball Aerospace and Technologies Corp., The Institute of Optics, University of Rochester, University of Rochester [USA], University of California [Santa Cruz] (UCSC), University of California, Makenzie Lystrup, Marshall D. Perrin, Natalie Batalha, Nicholas Siegler, and Edward C. Tong
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Aperture ,Computer science ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,FOS: Physical sciences ,01 natural sciences ,Deformable mirror ,law.invention ,010309 optics ,Telescope ,Error budget ,law ,0103 physical sciences ,Sensitivity (control systems) ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,010303 astronomy & astrophysics ,Coronagraph ,Simulation ,Segmented telescope ,Measure (data warehouse) ,Wavefront requirements ,Testbed ,Wavefront sensing and control ,Exoplanet ,[SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM] ,Upgrade ,High-contrast imaging ,Wavefront error tolerancing ,Astrophysics - Instrumentation and Methods for Astrophysics ,[SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing ,Cophasing - Abstract
This paper presents the setup for empirical validations of the Pair-based Analytical model for Segmented Telescope Imaging from Space (PASTIS) tolerancing model for segmented coronagraphy. We show the hardware configuration of the High-contrast imager for Complex Aperture Telescopes (HiCAT) testbed on which these experiments will be conducted at an intermediate contrast regime between $10^{-6}$ and $10^{-8}$. We describe the optical performance of the testbed with a classical Lyot coronagraph and describe the recent hardware upgrade to a segmented mode, using an IrisAO segmented deformable mirror. Implementing experiments on HiCAT is made easy through its top-level control infrastructure that uses the same code base to run on the real testbed, or to invoke the optical simulator. The experiments presented in this paper are run on the HiCAT testbed emulator, which makes them ready to be performed on actual hardware. We show results of three experiments with results from the emulator, with the goal to demonstrate PASTIS on hardware next. We measure the testbed PASTIS matrix, and validate the PASTIS analytical propagation model by comparing its contrast predictions to simulator results. We perform the tolerancing analysis on the optical eigenmodes (PASTIS modes) and on independent segments, then validate these results in respective experiments. This work prepares and enables the experimental validation of the analytical segment-based tolerancing model for segmented aperture coronagraphy with the specific application to the HiCAT testbed., Comment: 18 pages, 9 figures, published
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- 2020
11. Analytical model-based analysis of long-exposure images from ground-based telescopes
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Gérard Rousset, Lucie Leboulleux, Pierre Baudoz, Raphaël Galicher, and Eric Gendron
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Wavefront ,Image quality ,Computer science ,Real-time computing ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Astrophysics::Instrumentation and Methods for Astrophysics ,Process (computing) ,Phase (waves) ,Starlight ,law.invention ,law ,Astrophysics::Earth and Planetary Astrophysics ,Adaptive optics ,Coronagraph ,Spectrograph - Abstract
The search for Earth-like exoplanets requires high-contrast and high-angular resolution instruments, which designs can be very complex: they need an adaptive optics system to compensate for the effect of the atmospheric turbulence on image quality and a coronagraph to reduce the starlight and enable the companion imaging. During the instrument design phase and the error budget process, studies of performance as a function of optical errors are needed and require multiple end-to-end numerical simulations of wavefront errors through the optical system. In particular, the detailed analysis of long-exposure images enables to evaluate the image quality (photon noise level, impact of optical aberrations and of adaptive optics residuals, etc.). Nowadays simulating one long but finite exposure image means drawing several thousands of random frozen phase screens, simulating the image associated with each of them after propagation through the imaging instrument, and averaging all the images. Such a process is time consuming, demands a great deal of computer resources, and limits the number of parametric optimization. We propose an alternative and innovative method to directly express the statistics of ground-based images for long but finite exposure times. It is based on an analytical model, which only requires the statistical properties of the atmospheric turbulence. Such a method can be applied to optimize the design of future instruments such as SPHERE+ (VLT) or the planetary camera and spectrograph (PCS - ELT) or any ground-based instrument.
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- 2020
12. A socio-demographic study of the exoplanet direct imaging community
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Elsa Huby, Garima Singh, Lucie Leboulleux, Faustine Cantalloube, Elodie Choquet, Observatoire de Paris, Université Paris sciences et lettres (PSL), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Max-Planck-Institut für Astronomie (MPIA), and Max-Planck-Gesellschaft
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0301 basic medicine ,[PHYS.ASTR.IM]Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM] ,[PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP] ,Socio demographics ,FOS: Physical sciences ,Direct imaging ,01 natural sciences ,Representation (politics) ,03 medical and health sciences ,demographics ,0103 physical sciences ,gender ,Seniority ,10. No inequality ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,010303 astronomy & astrophysics ,business.industry ,Field (Bourdieu) ,Public relations ,minorities ,Social relation ,high-contrast imaging ,030104 developmental biology ,exoplanets ,Astrophysics - Instrumentation and Methods for Astrophysics ,Psychology ,business ,Inclusion (education) ,Social behavior - Abstract
Astronomy and science are fields in which specific groups remain under-represented despite multiple studies that investigate this issue and propose solutions. In this article, we analyze the demographics and social behavior of the exoplanet direct imaging community. Our focus is on identifying possible under-representation among this group, and quantifying inappropriate social behaviors. During the Spirit of Lyot conference 2019 (Tokyo, Japan), we conducted a survey that gathered a participation rate of 53\%. We analyzed the data collected under the prisms of gender balance and seniority representation. The proportions of women and of non-binary persons reveal a more diverse community in comparison to the other scientific groups (e.g. the IAU members), but still far from a balanced representation of all genders. Early-career scientists appear to have a lower visibility in the field than permanent researchers, with PhD students being under-represented at international conferences, and postdocs being excluded from conference Science Organizing Committees. Regarding social relations, the results are alarming, in particular when it comes to self-censoring of women or to unprofessional behavior, which was experienced by 54\% of this community (gender-biased behavior: 29\%; oral interruption: 33\%; inappropriate behavior: 33\%), and in particular by women. We recommend the community to become pro-active to build a safe environment and to continue its inclusion efforts. One aspect could be to systematically include socio-demographic surveys in conference registration forms to monitor the evolution of the community, in particular at larger scales. To do so, the survey questions available on GitHub., Comment: 17 pages, 14 figures
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- 2020
13. High-contrast imager for complex aperture telescopes (HiCAT): 6. Two deformable mirror wavefront control (Conference Presentation)
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Anand Sivaramakrishnan, Iva Laginja, Ana-Maria Valenzuela, Keira Brooks, Scott D. Will, Jean-François Sauvage, Gregory R. Brady, Heather Kurtz, Peter Petrone, Roser Juanola-Parramon, Thomas Comeau, Nathan Scott, Marshall D. Perrin, Ron Shiri, Neil T. Zimmerman, Lucie Leboulleux, Julia Fowler, Rémi Soummer, Kathryn St. Laurent, Laurent Pueyo, Evelyn McChesney, Laurent M. Mugnier, Johan Mazoyer, James Noss, John G. Hagopian, Rob Gontrum, Emmanuel Hugot, Kevin Fogarty, Mamadou N'Diaye, and Marc Ferrari
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Wavefront ,Computer science ,Zernike polynomials ,business.industry ,Aperture ,Astrophysics::Instrumentation and Methods for Astrophysics ,Wavefront sensor ,Deformable mirror ,law.invention ,Starlight ,Telescope ,symbols.namesake ,Optics ,law ,symbols ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,business ,Coronagraph - Abstract
The goal of the High-contrast imager for Complex Aperture Telescopes (HiCAT) testbed is to demonstrate coronagraphic starlight suppression solutions for future segmented aperture space telescopes such as the Large UV, Optical, IR telescope (LUVOIR) mission concept being studied by NASA. The testbed design has the flexibility to enable studies with increasing complexity for telescope aperture geometries starting with off-axis telescopes, then on-axis telescopes with central obstruction and support structures. The testbed implements the Apodized Pupil Lyot Coronagraph (APLC) optimized for the HiCAT aperture, which is similar to one of the possible geometries considered for LUVOIR. Wavefront can be controlled using continuous deformable mirrors, and wavefront sensing is performed using the imaging camera, or a dedicated phase retrieval camera, and also in a low-order wavefront sensing arm. We present a progress update of the testbed in particular results using two deformable mirror control to produce high-contrast dark zone, and preliminary results using the testbed’s low order Zernike wavefront sensor.
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- 2019
14. Wavefront error tolerancing for direct imaging of exo-Earths with a large segmented telescope in space
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Rémi Soummer, J. Scott Knight, Emiel H. Por, James Noss, Kathryn St. Laurent, Iva Laginja, Jean-François Sauvage, Laurent Pueyo, Lucie Leboulleux, Laura E. Coyle, Laurent M. Mugnier, Space Telescope Science Institute (STSci), DOTA, ONERA, Université Paris Saclay (COmUE) [Châtillon], ONERA-Université Paris Saclay (COmUE), Ball Aerospace and Technologies Corp., Leiden Observatory [Leiden], and Universiteit Leiden [Leiden]
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Computer science ,FOS: Physical sciences ,01 natural sciences ,wavefront sensing and control ,010305 fluids & plasmas ,law.invention ,Telescope ,[SPI]Engineering Sciences [physics] ,Optics ,law ,coronagraphy ,0103 physical sciences ,Orthonormal basis ,exoplanet ,Adaptive optics ,010303 astronomy & astrophysics ,Coronagraph ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Segmented telescope ,Wavefront ,[PHYS]Physics [physics] ,HabEX ,business.industry ,high-contrast imag- ing ,Astrophysics::Instrumentation and Methods for Astrophysics ,cophasing ,LUVOIR ,Phaser ,Exoplanet ,error budget ,Cophasing ,Computer Science::Computer Vision and Pattern Recognition ,business ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
Direct imaging of exo-Earths and search for life is one of the most exciting and challenging objectives for future space observatories. Segmented apertures in space will be required to reach the needed large diameters beyond the capabilities of current or planned launch vehicles. These apertures present additional challenges for high-contrast coronagraphy, not only in terms of static phasing but also in terms of their stability. The Pair-based Analytical model for Segmented Telescope Imaging from Space (PASTIS) was developed to model the effects of segment-level optical aberrations on the final image contrast. In this paper, we extend the original PASTIS propagation model from a purely analytical to a semi-analytical method, in which we substitute the use of analytical images with numerically simulated images. The inversion of this model yields a set of orthonormal modes that can be used to determine segment-level wavefront tolerances. We present results in the case of segment-level piston error applied to the baseline coronagraph design of LUVOIR A, with minimum and maximum wavefront error constraint between 56 pm and 290 pm per segment. The analysis is readily generalizable to other segment-level aberrations modes, and can also be expanded to establish stability tolerances for these missions., Comment: 15 pages, 10 figures; published
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- 2019
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15. Experimental validation of coronagraphic focal-plane wavefront sensing for future segmented space telescopes
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Thierry Fusco, Jean-François Sauvage, Peter Petrone, Christopher Moriarty, Laurent M. Mugnier, Rémi Soummer, Laurent Pueyo, Lucie Leboulleux, Keira Brooks, Space Telescope Science Institute (STSci), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
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planets and satellites: detection ,Aperture ,FOS: Physical sciences ,Astrophysics ,01 natural sciences ,law.invention ,010309 optics ,Primary mirror ,Optics ,instrumentation: high angular resolution ,law ,0103 physical sciences ,Piston (optics) ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,010303 astronomy & astrophysics ,Coronagraph ,[PHYS]Physics [physics] ,Wavefront ,Physics ,business.industry ,Astrophysics::Instrumentation and Methods for Astrophysics ,techniques: high angular resolution ,Astronomy and Astrophysics ,Tilt (optics) ,Cardinal point ,Space and Planetary Science ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,business ,Focus (optics) - Abstract
Direct imaging of Earth-like planets from space requires dedicated observatories, combining large segmented apertures with instruments and techniques such as coronagraphs, wavefront sensors, and wavefront control in order to reach the high contrast of 10^10 that is required. The complexity of these systems would be increased by the segmentation of the primary mirror, which allows for the larger diameters necessary to image Earth-like planets but also introduces specific patterns in the image due to the pupil shape and segmentation and making high-contrast imaging more challenging. Among these defects, the phasing errors of the primary mirror are a strong limitation to the performance. In this paper, we focus on the wavefront sensing of segment phasing errors for a high-contrast system, using the COronagraphic Focal plane wave-Front Estimation for Exoplanet detection (COFFEE) technique. We implemented and tested COFFEE on the High-contrast imaging for Complex Aperture Telescopes (HiCAT) testbed, in a configuration without any coronagraph and with a classical Lyot coronagraph, to reconstruct errors applied on a 37 segment mirror. We analysed the quality and limitations of the reconstructions. We demonstrate that COFFEE is able to estimate correctly the phasing errors of a segmented telescope for piston, tip, and tilt aberrations of typically 100nm RMS. We also identified the limitations of COFFEE for the reconstruction of low-order wavefront modes, which are highly filtered by the coronagraph. This is illustrated using two focal plane mask sizes on HiCAT. We discuss possible solutions, both in the hardware system and in the COFFEE optimizer, to mitigate these issues., Comment: 12 pages, 15 figures, Astronomy & Astrophysics
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- 2020
16. Sensitivity analysis for high-contrast imaging with segmented space telescopes
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Lucie Leboulleux, Laurent Pueyo, Anand Sivaramakrishnan, Thierry Fusco, Mamadou N'Diaye, Jean-François Sauvage, Johan Mazoyer, Rémi Soummer, Space Telescope Science Institute (STSci), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA, Université Paris Saclay (COmUE) [Châtillon], ONERA-Université Paris Saclay (COmUE), Department of Physics and Astronomy [Baltimore], Johns Hopkins University (JHU), Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
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ZERNIKE POLYNOMIALS ,Computer science ,Zernike polynomials ,MIRRORS ,Interference (wave propagation) ,01 natural sciences ,law.invention ,010309 optics ,Telescope ,symbols.namesake ,Optics ,law ,0103 physical sciences ,Angular resolution ,Sensitivity (control systems) ,VORTEX CORONAGRAPH ,010303 astronomy & astrophysics ,EXOPLANETE ,Wavefront ,COPHASING ,SPACE TELESCOPES ,business.industry ,Angular distance ,Astrophysics::Instrumentation and Methods for Astrophysics ,COMPUTER SIMULATIONS ,Cophasing ,HIGH-CONTRAST IMAGING ,CORONAGRAPHY ,POINT SPREAD FUNCTIONS ,Computer Science::Computer Vision and Pattern Recognition ,symbols ,business ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] - Abstract
International audience; Direct imaging and spectroscopy of Earth-like planets will require high-contrast imaging at very close angular separation: 1e10 star to planet ux ratio at a few tenths of an arcsecond. Large telescopes in space are necessary to provide sufficient collecting area and angular resolution to achieve this goal. In the static case, coronagraphic instrument designs combined with wavefront control techniques have been optimized for segmented on-axis telescope geometries, but the extreme wavefront stability required at very high contrast of the order of tens of picometers remains one of the main challenges. Indeed, cophasing errors and instabilities directly contribute to the degradation of the final image contrast. A systematic understanding is therefore needed to quantify and optimize the static and dynamic constraints on segment phasing. We present an analytical model: Pair-based Analytical model for Segmented Telescopes Imaging from Space (PASTIS), which enables quasi-instantaneous analytical evaluations of the impact of segment-level aberrations and phasing on the image contrast. This model is based on a multiple sum of Young interference fringes between pairs of segments and produces short and long exposure coronagraphic images with a segmented telescope in presence of local phase aberrations on each segment. PASTIS matches end-to-end numerical simulations with high-fidelity (3% rms error on the contrast). Moreover, the model can be inverted by dint of a projection on the singular modes of the phase to provide constraints on each Zernike polynomial for each segment. These singular modes provide information on the contrast sensitivity to segment-level phasing errors in the pupil, which can be used to derive constraints on both static and dynamic mitigation strategies (e.g. backplane geometry or segment vibration sensing and control). The few most sensitive modes can be well identified and must be controlled at the level of tens of picometers, while the least sensitive modes in the hundreds of picometers. This novel formalism enables a fast and efficient sensitivity analysis for any segmented telescopes, in both static and dynamic modes.
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- 2018
17. High-contrast imager for complex aperture telescopes (HiCAT): 5. first results with segmented-aperture coronagraph and wavefront control
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Thomas Comeau, Elodie Choquet, Mamadou N'Diaye, Iva Laginja, Lucie Leboulleux, Anand Sivaramakrishnan, Laurent Pueyo, Ron Shiri, Peter Petrone, Kathryn St. Laurent, Gregory R. Brady, Sylvain Egron, Johan Mazoyer, Rob Gontrum, Thomas E. Dillon, Marshall D. Perrin, Neil Zimmerman, Rémi Soummer, Keira Brooks, A. J. Eldorado Riggs, John G. Hagopian, Ana-Maria Valenzuela, Space Telescope Science Institute (STSci), Caltech Department of Astronomy [Pasadena], California Institute of Technology (CALTECH), University of Delaware [Newark], Iridescence SARL, Advanced Nanophotonics, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA, Université Paris Saclay (COmUE) [Châtillon], ONERA-Université Paris Saclay (COmUE), SigmaSpace Corporation [Lanham, MD], Johns Hopkins University (JHU), Observatoire de la Côte d'Azur (OCA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), NASA Goddard Space Flight Center (GSFC), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Lystrup, Makenzie, MacEwen, Howard A., Fazio, Giovanni G., Batalha, Natalie, Siegler, Nicholas, and Tong, Edward C.
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Aperture ,Computer science ,Apodized Pupil Lyot Coronagraph ,FOS: Physical sciences ,WAVEFRONTS ,01 natural sciences ,CARBON NANOTUBES ,Deformable mirror ,law.invention ,010309 optics ,Telescope ,[SPI]Engineering Sciences [physics] ,Optics ,Software ,Segmented telescopes ,law ,coronagraphy ,0103 physical sciences ,exoplanet ,010303 astronomy & astrophysics ,Coronagraph ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Wide Field Infrared Survey Telescope ,APLC ,Wavefront ,[PHYS]Physics [physics] ,coronagraphy testbed ,SPACE TELESCOPES ,business.industry ,Astrophysics::Instrumentation and Methods for Astrophysics ,METROLOGY ,PHASE RETRIEVAL ,Starlight ,high-contrast imaging ,TELESCOPES ,Astrophysics::Earth and Planetary Astrophysics ,business ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
Segmented telescopes are a possibility to enable large-aperture space telescopes for the direct imaging and spectroscopy of habitable worlds. However, the complexity of their aperture geometry, due to the central obstruction, support structures and segment gaps, makes high-contrast imaging challenging. The High-contrast Imager for Complex Aperture Telescopes (HiCAT) testbed was designed to study and develop solutions for such telescope pupils using wavefront control and coronagraphic starlight suppression. The testbed design has the flexibility to enable studies with increasing complexity for telescope aperture geometries: off-axis telescopes, on-axis telescopes with central obstruction and support structures - e.g. the Wide Field Infrared Survey Telescope (WFIRST) - to on-axis segmented telescopes, including various concepts for a Large UV, Optical, IR telescope (LUVOIR). In the past year, HiCAT has made significant hardware and software updates to accelerate the development of the project. In addition to completely overhauling the software that runs the testbed, we have completed several hardware upgrades, including the second and third deformable mirror, and the first custom Apodized Pupil Lyot Coronagraph (APLC) optimized for the HiCAT aperture, which is similar to one of the possible geometries considered for LUVOIR. The testbed also includes several external metrology features for rapid replacement of parts, and in particular the ability to test multiple apodizers readily, an active tip-tilt control system to compensate for local vibration and air turbulence in the enclosure. On the software and operations side, the software infrastructure enables 24/7 automated experiments that include routine calibration tasks and high-contrast experiments. We present an overview and status update of the project, on the hardware and software side, and describe results obtained with APLC WFC., Comment: 16 pages, 12 figures
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- 2018
18. Phase-retrieval-based wavefront metrology for high contrast coronagraphy
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Iva Laginja, Christopher Moriarty, Peter Petrone, Keira Brooks, Rémi Soummer, Thomas Comeau, Gregory R. Brady, Lucie Leboulleux, Space Telescope Science Institute (STSci), Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), DOTA, ONERA, Université Paris Saclay (COmUE) [Châtillon], ONERA-Université Paris Saclay (COmUE), and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)
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Aperture ,FOS: Physical sciences ,010103 numerical & computational mathematics ,01 natural sciences ,WAVEFRONTS-SENSING ,010309 optics ,[SPI]Engineering Sciences [physics] ,Optics ,0103 physical sciences ,Calibration ,0101 mathematics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Parametric statistics ,Physics ,Wavefront ,[PHYS]Physics [physics] ,Measurement method ,High contrast ,business.industry ,DEFORMABLE MIRROR ,PHASE RETRIEVAL ,CORONAGRAPH ,Metrology ,HIGH-CONTRAST IMAGING ,Phase retrieval ,business ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
We discuss the use of parametric phase-diverse phase retrieval as an in-situ high-fidelity wavefront measurement method to characterize and optimize the transmitted wavefront of a high-contrast coronagraphic instrument. We apply our method to correct the transmitted wavefront of the HiCAT (High contrast imager for Complex Aperture Telescopes) coronagraphic testbed. This correction requires a series of calibration steps, which we describe. The correction improves the system wavefront from 16 nm RMS to 3.0 nm RMS., 13 pages, 12 figures
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- 2018
19. Towards the experimental validation of the non-linear dark hole on the THD bench
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Olivier Herscovici-Schiller, Kjetil Dohlen, Arthur Vigan, Laurent M. Mugnier, Jean-Michel Le Duigou, Fabien Patru, Rémi Soummer, Pierre Baudoz, Thierry Fusco, Lucie Leboulleux, Laurent Pueyo, Raphaël Galicher, Jean-François Sauvage, DTIS, ONERA, Université Paris Saclay (COmUE) [Palaiseau], ONERA-Université Paris Saclay (COmUE), DOTA, ONERA, Université Paris Saclay (COmUE) [Châtillon], Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), European Southern Observatory (ESO), Gemini Observatory [Southern Operations Center], Association of Universities for Research in Astronomy (AURA), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Space Telescope Science Institute (STSci), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), DTIS, ONERA, Université Paris Saclay [Palaiseau], ONERA-Université Paris-Saclay, DOTA, ONERA, Université Paris Saclay [Châtillon], and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
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Wavefront ,Total harmonic distortion ,[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,Computer science ,business.industry ,Phase (waves) ,Astrophysics::Instrumentation and Methods for Astrophysics ,01 natural sciences ,Exoplanet ,Space exploration ,law.invention ,Starlight ,010309 optics ,Optics ,Planet ,law ,0103 physical sciences ,Astrophysics::Earth and Planetary Astrophysics ,business ,010303 astronomy & astrophysics ,Coronagraph - Abstract
International audience; New space missions dedicated to exoplanet imaging will rely on coronagraphs to address the high contrast between the stars and their environments. In order to avoid the image of planets to be lost in post-coronagraphic starlight residuals, high precision wavefront sensing and control is a key element to these missions. We present recent results of simultaneous post-coronagraphic phase and amplitude sensing obtained on the THD bench using the coronagraphic phase diversity. We also present results of simulation studies on the non-linear dark hole technique to assess the main limitations of this technique. Finally, we present a first experimental validation of its principle and corroborate expectations on its speed of convergence. These results suggest that the non-linear dark hole is a good candidate for wave-front control for future space-based exoplanet imaging missions, where fast techniques to produce deep dark holes are of paramount importance.
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- 2018
20. Pair-based Analytical model for Segmented Telescopes Imaging from Space for sensitivity analysis
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Laurent Pueyo, Olivier Fauvarque, Mamadou N'Diaye, Jean-François Sauvage, Johan Mazoyer, Lucie Leboulleux, Rémi Soummer, Anand Sivaramakrishnan, Thierry Fusco, Space Telescope Science Institute (STSci), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA, Université Paris Saclay (COmUE) [Châtillon], ONERA-Université Paris Saclay (COmUE), Johns Hopkins University (JHU), Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)
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Computer science ,Aperture ,Mechanical Engineering ,James Webb Space Telescope ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy and Astrophysics ,Context (language use) ,Image segmentation ,Systems modeling ,01 natural sciences ,Electronic, Optical and Magnetic Materials ,Term (time) ,[SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM] ,010309 optics ,Cophasing ,Space and Planetary Science ,Control and Systems Engineering ,0103 physical sciences ,Sensitivity (control systems) ,010303 astronomy & astrophysics ,Instrumentation ,Algorithm - Abstract
International audience; The imaging and spectroscopy of habitable worlds will require large-aperture space-based telescopes, to increase the collecting area and the angular resolution. These large telescopes will necessarily use segmented primaries to fit in a rocket. However, these massively segmented mirrors make high-contrast performance very difficult to achieve and stabilize, compared to more common monolithic primaries. Despite space telescopes operating in a friendlier environment than ground-based telescopes, remaining vibrations and resonant modes on the segments can still deteriorate the performance. In this context, we present the Pair-based Analytical model for Segmented Telescopes Imaging from Space (PASTIS) that enables the establishment of a comprehensive error budget, both in term of segment alignment and stability. Using this model, one may evaluate the influence of the segment cophasing and surface quality evolution on the final images and contrasts, and set up requirements for any given mission. One can also identify the dominant modes of a given geometry for a given coronagraphic instrument and design the feedback control systems accordingly. In this paper, we first develop and validate this analytical model by comparing its outputs to the images and contrasts predicted by an end-to-end simulation. We show that the contrasts predicted using PASTIS are accurate enough compared to the end-to-end propagation results, at the exo-Earth detection level. Second, we develop a method for a fast and efficient error budget in term of segment manufacturing and alignment that takes into account the disparities of the segment effects on the final performance. This technique is then applied on a specific aperture to provide static and quasi-static requirements on each segment for local piston and 45 •-astigmatism aberrations. Finally we discuss potential application of this new technique to future missions.
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- 2018
21. Active Correction of Aperture Discontinuities-Optimized Stroke Minimization. I. A New Adaptive Interaction Matrix Algorithm
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Colin Norman, Stuart Shaklan, Mamadou N'Diaye, Laurent Pueyo, Neil Zimmerman, Lucie Leboulleux, K. St. Laurent, Kevin Fogarty, Johan Mazoyer, Rémi Soummer, Space Telescope Science Institute (STSci), Technologies et systèmes d'information pour les agrosystèmes (UR TSCF), Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), NASA Goddard Space Flight Center (GSFC), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA, Université Paris Saclay (COmUE) [Châtillon], ONERA-Université Paris Saclay (COmUE), Laboratoire de Physique des Matériaux Divisés et des Interfaces (LPMDI), Université Paris-Est Marne-la-Vallée (UPEM)-Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre national du machinisme agricole, du génie rural, des eaux et forêts (CEMAGREF), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), DOTA, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, and California Institute of Technology (CALTECH)-NASA
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Physics ,[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,Aperture ,Astrophysics::Instrumentation and Methods for Astrophysics ,FOS: Physical sciences ,Astronomy and Astrophysics ,Classification of discontinuities ,Image plane ,01 natural sciences ,Deformable mirror ,law.invention ,010309 optics ,Telescope ,Primary mirror ,Space and Planetary Science ,law ,[SDU]Sciences of the Universe [physics] ,0103 physical sciences ,Astrophysics::Earth and Planetary Astrophysics ,Secondary mirror ,Astrophysics - Instrumentation and Methods for Astrophysics ,010303 astronomy & astrophysics ,Coronagraph ,Algorithm ,Instrumentation and Methods for Astrophysics (astro-ph.IM) - Abstract
Future searches for biomarkers on habitable exoplanets will rely on telescope instruments that achieve extremely high contrast at small planet-to-star angular separations. Coronagraphy is a promising starlight suppression technique, providing excellent contrast and throughput for off-axis sources on clear apertures. However, the complexity of space- and ground-based telescope apertures goes on increasing over time, owing to the combination of primary mirror segmentation, secondary mirror, and support structures. These discontinuities in the telescope aperture limit the coronagraph performance. In this paper, we present ACAD-OSM, a novel active method to correct for the diffractive effects of aperture discontinuities in the final image plane of a coronagraph. Active methods use one or several deformable mirrors that are controlled with an interaction matrix to correct for the aberrations in the pupil. However, they are often limited by the amount of aberrations introduced by aperture discontinuities. This algorithm relies on the recalibration of the interaction matrix during the correction process to overcome this limitation. We first describe the ACAD-OSM technique and compare it to the previous active methods for the correction of aperture discontinuities. We then show its performance in terms of contrast and off-axis throughput for static aperture discontinuities (segmentation, struts) and for some aberrations evolving over the life of the instrument (residual phase aberrations, artifacts in the aperture, misalignments in the coronagraph design). This technique can now obtain the earth-like planet detection threshold of 10^(-10) contrast on any given aperture over at least a 10% spectral bandwidth, with several coronagraph designs., Comment: 14 pages, 21 figures, accepted for publication in The Astronomical Journal
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- 2018
22. James Webb Space telescope optical simulation testbed: experimental results with linear control alignment
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Emmanuel Hugot, Marc Ferrari, Thierry Fusco, Marshall D. Perrin, Elodie Choquet, Mamadou N'Diaye, Clément Escolle, Vincent Michau, Sylvain Egron, Rémi Soummer, Marie Ygouf, Laurent Pueyo, Lucie Leboulleux, Aurélie Bonnefois, and Charles-Philippe Lajoie
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- 2017
23. Sensitivity analysis for high-contrast missions with segmented telescopes
- Author
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Mamadou N'Diaye, Rémi Soummer, Laurent Pueyo, Jean-François Sauvage, Kathryn St. Laurent, Thierry Fusco, Lucie Leboulleux, Space Telescope Science Institute (STSci), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), ONERA - The French Aerospace Lab [Châtillon], ONERA-Université Paris Saclay (COmUE), Observatoire de la Côte d'Azur, and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)
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Aperture ,Computer science ,media_common.quotation_subject ,Context (language use) ,01 natural sciences ,law.invention ,010309 optics ,Telescope ,law ,Planet ,0103 physical sciences ,Contrast (vision) ,exoplanet ,Computer vision ,Sensitivity (control systems) ,010303 astronomy & astrophysics ,Segmented telescope ,media_common ,business.industry ,Astrophysics::Instrumentation and Methods for Astrophysics ,error budget ,Exoplanet ,[SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM] ,Cophasing ,high-contrast imaging ,Computer Science::Computer Vision and Pattern Recognition ,Astrophysics::Earth and Planetary Astrophysics ,Artificial intelligence ,business - Abstract
International audience; Segmented telescopes enable large-aperture space telescopes for the direct imaging and spectroscopy of habitable worlds. However, the increased complexity of their aperture geometry, due to their central obstruction, support structures, and segment gaps, makes high-contrast imaging very challenging. In this context, we present an analytical model that will enable to establish a comprehensive error budget to evaluate the constraints on the segments and the influence of the error terms on the final image and contrast. Indeed, the target contrast of 10^10 to image Earth-like planets requires drastic conditions, both in term of segment alignment and telescope stability. Despite space telescopes evolving in a more friendly environment than ground-based telescopes, remaining vibrations and resonant modes on the segments can still deteriorate the contrast. In this communication, we develop and validate the analytical model, and compare its outputs to images issued from end-to-end simulations.
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- 2017
24. Capabilities of ACAD-OSM, an active method for the correction of aperture discontinuities
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Sylvain Egron, Lucie Leboulleux, Colin Norman, Kevin Fogarty, Laurent Pueyo, Johan Mazoyer, Mamadou N'Diaye, Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS), Observatoire de la Côte d'Azur (OCA), and Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
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[PHYS]Physics [physics] ,Aperture ,Computer science ,business.industry ,Astrophysics::Instrumentation and Methods for Astrophysics ,Phase (waves) ,FOS: Physical sciences ,Active optics ,Classification of discontinuities ,01 natural sciences ,Deformable mirror ,law.invention ,010309 optics ,Optics ,Apodization ,[SDU]Sciences of the Universe [physics] ,law ,0103 physical sciences ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics ,business ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,010303 astronomy & astrophysics ,Throughput (business) ,Coronagraph - Abstract
The increasing complexity of the aperture geometry of the future space- and ground based-telescopes will limit the performance of the next generation of coronagraphic instruments for high contrast imaging of exoplanets. We propose here a new closed-loop optimization technique using two deformable mirrors to correct for the effects of complex apertures on coronagraph performance, alternative to the ACAD technique previously developed by our group. This technique, ACAD-OSM, allows the use of any coronagraphs designed for continuous apertures, with complex, segmented, apertures, maintaining high performance in contrast and throughput. We show the capabilities of this technique on several pupil geometries (segmented LUVOIR type aperture, WFIRST, ELTs) for which we obtained high contrast levels with several deformable mirror setups (size, number of actuators, separation between them), coronagraphs (apodized pupil Lyot and vortex coronagraphs) and spectral bandwidths, which will help us present recommendations for future coronagraphic instruments. We show that this active technique handles, without any revision to the algorithm, changing or unknown optical aberrations or discontinuities in the pupil, including optical design misalignments, missing segments and phase errors., Comment: To appear in the Proceedings of the SPIE: Techniques and Instrumentation for Detection of Exoplanets VIII
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- 2017
25. Comparison of wavefront control algorithms and first results on the high-contrast imager for complex aperture telescopes (hicat) testbed
- Author
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Elodie Choquet, Laurent Pueyo, T. Fusco, Mamadou N'Diaye, Johan Mazoyer, Rémi Soummer, Marshall D. Perrin, Jean-François Sauvage, Lucie Leboulleux, Sylvain Egron, Space Telescope Science Institute (STSci), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), ONERA - The French Aerospace Lab [Châtillon], ONERA-Université Paris Saclay (COmUE), Jet Propulsion Laboratory (JPL), and NASA-California Institute of Technology (CALTECH)
- Subjects
Physics ,Wavefront ,Infrared ,business.industry ,Aperture ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Exoplanet ,Deformable mirror ,Primary mirror ,Speckle pattern ,Optics ,[SDU]Sciences of the Universe [physics] ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,business ,Astrophysics::Galaxy Astrophysics ,Wide Field Infrared Survey Telescope - Abstract
The next generation of space telescopes for direct imaging and spectroscopy of exoplanets includes telescopes with a monolithic mirror, such as the Wide Field Infrared Survey Telescope (WFIRST) [1] and Large Ultra-Violet Optical Infrared (LUVOIR) telescopes with segmented primary mirror, like ATLAST [2, 3] or HDST [4].
- Published
- 2017
26. James Webb Space Telescope optical simulation testbed IV: linear control alignment of the primary segmented mirror and the secondary mirror
- Author
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Laurent Pueyo, Vincent Michau, Mamadou N'Diaye, Charles-Philippe Lajoie, Marshall D. Perrin, Sylvain Egron, Marc Ferrari, Elodie Choquet, Peter Petrone, Lucie Leboulleux, Joseph D. Long, Anand Sivaramakrishnan, Rémi Soummer, Aurélie Bonnefois, Olivier Levecq, Johan Mazoyer, Space Telescope Science Institute (STSci), ONERA - The French Aerospace Lab [Châtillon], ONERA-Université Paris Saclay (COmUE), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Observatoire de la Côte d'Azur (OCA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
- Subjects
Wavefront ,Physics ,Linear control alignment ,JWST Linear control alignment Wavefront control Wavefront Sensing ,JWST ,Reflecting telescope ,Segmented mirror ,business.industry ,James Webb Space Telescope ,Cassegrain reflector ,Deformable mirror ,Primary mirror ,Optics ,[SDU]Sciences of the Universe [physics] ,Wavefront Sensing ,Secondary mirror ,business ,Wavefront control - Abstract
International audience; The James Webb Space Telescope (JWST) Optical Simulation Testbed (JOST) is a tabletop experiment designed to study wavefront sensing and control for a segmented space telescope, such as JWST. With the JWST Science & Operations Center co-located at STScI, JOST was developed to provide both a platform for staff training and to test alternate wavefront sensing and control strategies for independent validation or future improvements beyond the baseline operations. The design of JOST reproduces the physics of JWST's three-mirror anastigmat (TMA) using three custom aspheric lenses. It provides similar quality image as JWST (80% Strehl ratio) over a field equivalent to a NIRCam module, but at 633 nm. An Iris AO segmented mirror stands for the segmented primary mirror of JWST. Actuators allow us to control (1) the 18 segments of the segmented mirror in piston, tip, tilt and (2) the second lens, which stands for the secondary mirror, in tip, tilt and x, y, z positions. We present the most recent experimental results for the segmented mirror alignment. Our implementation of the Wavefront sensing (WFS) algorithms using phase diversity is tested on simulation and experimentally. The wavefront control (WFC) algorithms, which rely on a linear model for optical aberrations induced by misalignment of the secondary lens and the segmented mirror, are tested and validated both on simulations and experimentally. After alignment, JOST achieves 23 nm RMS WFE at 633 nm (RMS = lambda/28), which after accounting for the difference in design wavelengths, is comparable to the budgeted post-alignment WFE expected for JWST. We present the performance of the full active optic control loop in presence of perturbations on the segmented mirror, and we detail the quality of the alignment correction.
- Published
- 2017
27. Real-time implementation of an LQG tip-tilt controller for regular science observation on GeMS
- Author
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Caroline Kulcsár, Cristian Moreno, Vincent Garrel, Vanessa Montes, Pedro Gigoux, Benoit Neichel, Chad Trujillo, Jean-Marc Conan, Rémy Juvénal, Jeff Donahue, Marcos A. van Dam, Gaetano Sivo, Rodrigo Carrasco, Henri-François Raynaud, Lucie Leboulleux, Cyril Petit, Eduardo Marin, William Rambold, Gemini Observatory [Southern Operations Center], Association of Universities for Research in Astronomy (AURA), Laboratoire Charles Fabry / Spim, Laboratoire Charles Fabry (LCF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS), ONERA - The French Aerospace Lab [Châtillon], ONERA-Université Paris Saclay (COmUE), W.M. Keck Observatory, Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Laboratoire Charles Fabry / Imagerie et Information, Institut d'Optique Graduate School (IOGS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, Gemini Observatory, University of Hawai'i [Hilo], Flat Wavefronts, Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), SPIE, Enrico Marchetti, Laird M. Close, and Jean-Pierre Véran
- Subjects
Optimal Control ,Linear-quadratic-Gaussian control ,01 natural sciences ,[SPI.AUTO]Engineering Sciences [physics]/Automatic ,010309 optics ,Control theory ,0103 physical sciences ,Gemini Planet Imager ,LQG ,010303 astronomy & astrophysics ,GeMS ,ComputingMilieux_MISCELLANEOUS ,Simulation ,Physics ,Spectral density ,Natural frequency ,Kalman filter ,Optimal control ,Multi-Conjugated Adaptive Optics ,[SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM] ,Autoregressive model ,Integrator ,[SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic ,Adaptive Optics ,Vibrations Rejection ,Kalman Filter - Abstract
International audience; AO systems aim at detecting and correcting for optical distortions induced by atmospheric turbulences. They are also extremely sensitive to extraneous sources of perturbation such as vibrations, which degrade the performance. The Gemini South telescope has currently two main AO systems: the Gemini Multi Conjugated AO System GeMS and the Gemini Planet Imager GPI. GeMS is operational and regularly used for science observation delivering close to diffraction limit resolution over a large field of view (85×85 arcsec2). Performance limitation due to the use of an integrator for tip-tilt control is here explored. In particular, this type of controller does not allow for the mitigation of vibrations with an arbitrary natural frequency. We have thus implemented a tip-tilt Linear Quadratic Gaussian (LQG) controller with different underlying perturbation models: (i) a sum of autoregressive models of order 2 identified from an estimated power spectrum density (s-AR2) of the perturbation,1 already tested on CANARY2 and routinely used on SPHERE;3 (ii) cascaded ARMA models of order 2 identified using prediction error minimization (c-PEM) as proposed in.4, 5 Both s-AR2 and c-PEM were parameterized to produce tip or tilt state-space models up to order 20 and 30 respectively. We discuss the parallelized implementation in the real time computer and the expected performance. On-sky tests are scheduled during the November 2016 run or the January 2017 run.
- Published
- 2016
28. James Webb Space Telescope optical simulation testbed III: first experimental results with linear-control alignment
- Author
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Elodie Choquet, Mamadou N'Diaye, Sylvain Egron, Lucie Leboulleux, Emmanuel Hugot, Charles-Philippe Lajoie, Vincent Michau, Marie Ygouf, Laurent Pueyo, Marc Ferrari, Marshall D. Perrin, Thierry Fusco, Rémi Soummer, C. Escolle, and Aurélie Bonnefois
- Subjects
Physics ,Wavefront ,Segmented mirror ,business.industry ,James Webb Space Telescope ,Strehl ratio ,01 natural sciences ,Deformable mirror ,law.invention ,010309 optics ,Telescope ,Primary mirror ,Optics ,law ,0103 physical sciences ,Secondary mirror ,business ,010303 astronomy & astrophysics - Abstract
The James Webb Space Telescope (JWST) Optical Simulation Testbed (JOST) is a tabletop experiment designed to study wavefront sensing and control for a segmented space telescope, including both commissioning and maintenance activities. JOST is complementary to existing testbeds for JWST (e.g. the Ball Aerospace Testbed Telescope TBT) given its compact scale and flexibility, ease of use, and colocation at the JWST Science and Operations Center. The design of JOST reproduces the physics of JWST’s three-mirror anastigmat (TMA) using three custom aspheric lenses. It provides similar quality image as JWST (80% Strehl ratio) over a field equivalent to a NIRCam module, but at 633 nm. An Iris AO segmented mirror stands for the segmented primary mirror of JWST. Actuators allow us to control (1) the 18 segments of the segmented mirror in piston, tip, tilt and (2) the second lens, which stands for the secondary mirror, in tip, tilt and x, y, z positions. We present the full linear control alignment infrastructure developed for JOST, with an emphasis on multi-field wavefront sensing and control. Our implementation of the Wavefront Sensing (WFS) algorithms using phase diversity is experimentally tested. The wavefront control (WFC) algorithms, which rely on a linear model for optical aberrations induced by small misalignments of the three lenses, are tested and validated on simulations.
- Published
- 2016
29. High-contrast imager for Complex Aperture Telescopes (HiCAT). 4. Status and wavefront control development
- Author
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Elodie Choquet, Laurent Pueyo, Marshall D. Perrin, Lucie Leboulleux, Thierry Fusco, Sylvain Egron, Mamadou N'Diaye, Jeremy Kasdin, Jean-François Sauvage, A. J. Riggs, Rémi Soummer, Johan Mazoyer, Space Telescope Science Institute (STSci), Aix Marseille Université (AMU), ONERA - The French Aerospace Lab [Châtillon], ONERA-Université Paris Saclay (COmUE), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Department of Mechanical and Aerospace Engineering, Princeton University, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Centre National de la Recherche Scientifique (CNRS), Observatoire de la Côte d'Azur (OCA), and Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Segmented mirror ,Aperture ,01 natural sciences ,Deformable mirror ,law.invention ,010309 optics ,Telescope ,wavefront control ,Optics ,Speckle Nulling ,law ,0103 physical sciences ,Adaptive optics ,010303 astronomy & astrophysics ,Coronagraph ,Wide Field Infrared Survey Telescope ,vibration analysis ,Wavefront ,Physics ,business.industry ,Astrophysics::Instrumentation and Methods for Astrophysics ,high-contrast imaging ,exoplanets ,[SDU]Sciences of the Universe [physics] ,wavefront sensing ,business - Abstract
International audience; Segmented telescopes are a possible approach to enable large-aperture space telescopes for the direct imaging and spectroscopy of habitable worlds. However, the increased complexity of their aperture geometry, due to their central obstruction, support structures and segment gaps, makes high-contrast imaging very challenging. The High-contrast imager for Complex Aperture Telescopes (HiCAT) was designed to study and develop solutions for such telescope pupils using wavefront control and starlight suppression. The testbed design has the flexibility to enable studies with increasing complexity for telescope aperture geometries starting with off-axis telescopes, then on-axis telescopes with central obstruction and support structures (e.g. the Wide Field Infrared Survey Telescope [WFIRST]), up to on-axis segmented telescopes e.g. including various concepts for a Large UV, Optical, IR telescope (LUVOIR), such as the High Definition Space Telescope (HDST). We completed optical alignment in the summer of 2014 and a first deformable mirror was successfully integrated in the testbed, with a total wavefront error of 13nm RMS over a 18mm diameter circular pupil in open loop. HiCAT will also be provided with a segmented mirror conjugated with a shaped pupil representing the HDST configuration, to directly study wavefront control in the presence of segment gaps, central obstruction and spider. We recently applied a focal plane wavefront control method combined with a classical Lyot coronagraph on HiCAT, and we found limitations on contrast performance due to vibration effect. In this communication, we analyze this instability and study its impact on the performance of wavefront control algorithms. We present our Speckle Nulling code to control and correct for wavefront errors both in simulation mode and on testbed mode. This routine is first tested in simulation mode without instability to validate our code. We then add simulated vibrations to study the degradation of contrast performance in the presence of these effects.
- Published
- 2016
30. Changing the color of textiles with realistic visual rendering
- Author
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Justine Barbier, Lucie Roujas, Mathieu Hébert, Marine Page, Lucie Leboulleux, Lambert Henckens, and Anthony Cazier
- Subjects
Lightness ,Textile ,Computer science ,02 engineering and technology ,01 natural sciences ,law.invention ,Rendering (computer graphics) ,010309 optics ,Optics ,law ,0103 physical sciences ,Shadow ,Computer vision ,Hue ,Pixel ,business.industry ,Yarn ,021001 nanoscience & nanotechnology ,Gloss (optics) ,Achromatic lens ,visual_art ,visual_art.visual_art_medium ,Reflection (physics) ,Artificial intelligence ,0210 nano-technology ,business - Abstract
Fast and easy preview of a fabric without having to produce samples would be very profitable for textile designers, but remains a technological challenge. As a first step towards this objective, we study the possibility of making images of a real sample, and changing virtually the colors of its yarns while preserving the shine and shadow texture. We consider two types of fabrics: Jacquard weave fabrics made of polyester warp and weft yarns of different colors, and satin ribbons made of polyester and metallic yarns. For the Jacquard fabric, we make a color picture with a scanner on a sample in which the yarns have contrasted colors, threshold this image in order to distinguish the pixels corresponding to each yarn, and accordingly modify their hue and chroma values. This method is simple to operate but do not enable to simulate the angle-dependent shine. A second method, tested on the satin ribbon made of black polyester and achromatic metallic yarns, is based on polarized imaging. We analyze the polarization state of the reflected light which is different for dielectric and metallic materials illuminated by polarized light. We then add a fixed color value to the pixels representing the polyester yarns and modify the hue and chroma of the pixels representing the metallic yarns. This was performed for many incident angles of light, in order to render the twinkling effect displayed by these ribbons. We could verify through a few samples that the simulated previews reproduce real pictures with visually acceptable accuracy.
- Published
- 2015
31. James Webb Space Telescope Optical Simulation Testbed I: Overview and First Results
- Author
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Rachel Anderson, Elodie Choquet, Charles-Philippe Lajoie, Erin Elliott, Olivier Levecq, Sylvain Egron, Matt Mountain, Chris A. Long, Lucie Leboulleux, Marshall D. Perrin, Mamadou N'Diaye, Roeland P. van der Marel, Marie Ygouf, Laurent Pueyo, George F. Hartig, Rémi Soummer, Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS), Observatoire de la Côte d'Azur (OCA), and Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
[PHYS]Physics [physics] ,Wavefront ,Computer science ,business.industry ,James Webb Space Telescope ,Testbed ,Anastigmat ,FOS: Physical sciences ,Strehl ratio ,Deformable mirror ,law.invention ,Primary mirror ,Telescope ,Lens (optics) ,Spitzer Space Telescope ,[SDU]Sciences of the Universe [physics] ,law ,Aerospace engineering ,business ,Astrophysics - Instrumentation and Methods for Astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,ComputingMilieux_MISCELLANEOUS - Abstract
The James Webb Space Telescope (JWST) Optical Simulation Testbed (JOST) is a tabletop workbench to study aspects of wavefront sensing and control for a segmented space telescope, including both commissioning and maintenance activities. JOST is complementary to existing optomechanical testbeds for JWST (e.g. the Ball Aerospace Testbed Telescope, TBT) given its compact scale and flexibility, ease of use, and colocation at the JWST Science & Operations Center. We have developed an optical design that reproduces the physics of JWST's three-mirror anastigmat using three aspheric lenses; it provides similar image quality as JWST (80% Strehl ratio) over a field equivalent to a NIRCam module, but at HeNe wavelength. A segmented deformable mirror stands in for the segmented primary mirror and allows control of the 18 segments in piston, tip, and tilt, while the secondary can be controlled in tip, tilt and x, y, z position. This will be sufficient to model many commissioning activities, to investigate field dependence and multiple field point sensing & control, to evaluate alternate sensing algorithms, and develop contingency plans. Testbed data will also be usable for cross-checking of the WFS&C Software Subsystem, and for staff training and development during JWST's five- to ten-year mission., Proceedings of the SPIE, 9143-150. 13 pages, 8 figures
- Published
- 2014
32. High-contrast Imager for Complex Aperture Telescopes (HICAT): II. Design overview and first light results
- Author
-
Chris A. Long, Marc Ferrari, Marshall D. Perrin, Lucie Leboulleux, J. Kent Wallace, Erin Elliot, Mamadou N'Diaye, Audrey DiFelice, Emmanuel Hugot, Olivier Levecq, Rémi Soummer, Rachel Anderson, Elodie Choquet, Laurent Pueyo, Michel Marcos, Sylvain Egron, Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS), Observatoire de la Côte d'Azur (OCA), and Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Point spread function ,Diffraction ,Aperture ,Computer science ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Physics::Optics ,01 natural sciences ,law.invention ,010309 optics ,Primary mirror ,Telescope ,Optics ,law ,0103 physical sciences ,010303 astronomy & astrophysics ,Coronagraph ,ComputingMilieux_MISCELLANEOUS ,Wavefront ,[PHYS]Physics [physics] ,business.industry ,Testbed ,Astrophysics::Instrumentation and Methods for Astrophysics ,First light ,Starlight ,[SDU]Sciences of the Universe [physics] ,business - Abstract
We present a new high-contrast imaging testbed designed to provide complete solutions in wavefront sensing, control and starlight suppression with complex aperture telescopes. The testbed was designed to enable a wide range of studies of the effects of such telescope geometries, with primary mirror segmentation, central obstruction, and spiders. The associated diffraction features in the point spread function make high-contrast imaging more challenging. In particular the testbed will be compatible with both AFTA-like and ATLAST-like aperture shapes, respectively on-axis monolithic, and on-axis segmented telescopes. The testbed optical design was developed using a novel approach to define the layout and surface error requirements to minimize amplitude induced errors at the target contrast level performance. In this communication we compare the as-built surface errors for each optic to their specifications based on end-to-end Fresnel modelling of the testbed. We also report on the testbed optical and optomechanical alignment performance, coronagraph design and manufacturing, and preliminary first light results.
- Published
- 2014
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