A5070736407- Adaptive optics and wavefront sensing
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Optical measurement and interference techniques
- Optical Polarization and Ellipsometry
- Optical Systems and Laser Technology
- Advanced optical system design
- Astrophysics and Cosmic Phenomena
- Solar Thermal and Photovoltaic Systems
- solar cell performance optimization
- Calibration and Measurement Techniques
- Gamma-ray bursts and supernovae
- Particle Detector Development and Performance
- Photovoltaic System Optimization Techniques
- Dark Matter and Cosmic Phenomena
- Radiation Detection and Scintillator Technologies
- Solar Radiation and Photovoltaics
- Optical Coherence Tomography Applications
- Geophysics and Gravity Measurements
- Quantum Mechanics and Applications
- Astrophysics and Star Formation Studies
- Advanced Measurement and Metrology Techniques
- Astronomical Observations and Instrumentation
- Solar and Space Plasma Dynamics
- Particle Accelerators and Free-Electron Lasers
Institut de Planétologie et d'Astrophysique de Grenoble
2014-2024
Université Grenoble Alpes
2013-2023
Centre National de la Recherche Scientifique
2012-2022
Observatoire de la Côte d’Azur
2006-2017
Université Laval
2017
Université Joseph Fourier
2013-2016
IPAG Business School
2016
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2014
Institut de Recherche sur les Lois Fondamentales de l'Univers
2014
Institute for High Energy Physics
2014
The Nearby Supernova Factory (<i>Snfactory</i>) is an international experiment designed to lay the foundation for next generation of cosmology experiments (such as <i>CFHTLS</i>, <i>w</i>P, <i>SNAP</i> and <i>LSST</i>) which will measure expansion history Universe using Type Ia supernovae. <i>Snfactory</i> discover obtain frequent lightcurve spectrophotometry covering 3200-10000Å roughly 300 supernovae at low-redshift end smooth Hubble flow. quantity, quality, breadth galactic...
<i>Context. <i/>Among optical stellar interferometers, the CHARA Array located at Mt Wilson in California offers potential of very long baselines (up to 330 m) and prospect coupling multiple beam combiners. This paper presents principle measured performance VEGA, Visible spEctroGraph polArimeter installed September 2007 coherent focus array.<i>Aims. <i/>With 0.3 ms arc spatial resolution up spectral resolution, VEGA intends measure fundamental parameters stars, study activities image analyze...
ABSTRACT This paper presents an overview of SPIRou, the new-generation near-infrared spectropolarimeter/precision velocimeter recently installed on 3.6-m Canada–France–Hawaii Telescope (CFHT). Starting from two main science goals, i.e., quest for planetary systems around nearby M dwarfs and study magnetized star/planet formation, we outline instrument concept that was designed to efficiently address these forefront topics, detail in-lab on-sky performances measured throughout intensive...
SPIRou is a near-IR \'echelle spectropolarimeter and high-precision velocimeter under construction as next-generation instrument for the Canada-France-Hawaii-Telescope. It designed to cover very wide simultaneous spectral range (0.98-2.35 {\mu}m) at resolving power of 73.5K, providing unpolarized polarized spectra low-mass stars radial velocity (RV) precision 1m/s. The main science goals are detection habitable super-Earths around study how critically magnetic fields impact star / planet...
SNIFS is an integral field spectrograph devoted to the observation of supernovae. This instrument today in manufacturing phase and should be able observe supernovae at end this year (2003) on 2.2m telescope University Hawaii. The concept split 6" x view into 225 samples 0.4" through a microlens array. Then spectral decomposition each sample imaged 2k 4k CCD. In order cover all large range with high resolution, composed two modules, one for blue wavelengths (320 nm 560nm)with resolution...
Abstract This paper aims at optimizing the concentration ratio of multi-faceted focusing heliostats implemented into a solar tower power plant. The ideal shape heliostat located off-axis in field is known to be local section fictitious paraboloïd whose parameters are varying continuously with Sun angular position. We describe an optimization procedure applicable those heliostats. flux densities formed receiver and achievable concentrating ratios computed using improved convolution algorithm....
MAORY is one of the four instruments for E-ELT approved construction. It an adaptive optics module offering two compensation modes: multi-conjugate and single-conjugate optics. The project has recently entered its phase B. A system-level overview current status given in this paper.
MAORY is one of the approved instruments for European Extremely Large Telescope. It an adaptive optics module, enabling high-angular resolution observations in near infrared by real-time compensation wavefront distortions due to atmospheric turbulence and other disturbances such as wind action on telescope. An overview instrument design given this paper.
We describe MUSE (Multi Unit Spectroscopic Explorer), a second-generation integral-field spectrograph for the VLT, operating in visible and near IR wavelength range. It combines 1' x Field of View with improved spatial resolution (0.2") provided by adaptive optics covers large simultaneous spectral range (0.48 - 1 μm). With this unique combination capabilities, has wide domain application, discovery potential. will provide ultra deep fields limiting magnitude spectroscopy R = 28. After brief...
Context: Exoplanet science has made staggering progress in the last two decades, due to relentless exploration of new detection methods and refinement existing ones. Yet astrometry offers a unique untapped potential discovery habitable-zone low-mass planets around all solar-like stars solar neighborhood. To fulfill this goal, must be paired with high precision calibration detector. Aims: We present way calibrate detector for accuracy astrometry. An experimental testbed combining an...
The research and development activity on image slicer systems for integral field spectroscopy has increased in recent years, allowing the simultaneous observation same detector matrix of two‐dimensional sky maps spectral decomposition light. Nowadays, slicers lead to possible applications future instrumentation ground‐ space‐based telescopes, covering a domain ranging from UV mid‐IR wavelengths. Among such projects, MUSE (Multi Unit Spectroscopic Explorer) is an spectrograph proposed by...
The next generation of optical interferometers will provide high-resolution imaging celestial objects by using either the aperture synthesis technique or direct principle. To determine technical requirements, we have developed an interferometric test bench, called SIRIUS. preserve quality image, fast corrections path differences within a fraction wavelength to be applied: this is cophasing array, whereas making it coherent aims at stabilizing coherence length. In SIRIUS and are achieved...
The Cherenkov Telescope Array (CTA) will be the largest cosmic gamma ray detector ever built in world. It installed at two different sites North and South hemispheres should operational for about 30 years. In order to cover desired energy range, CTA is composed of typically 50-100 collecting telescopes various sizes (from 6 24-m diameters). Most them are equipped with a focal plane camera consisting 1500 2000 Photomultipliers (PM) light concentrating optics, whose double function maximize...
The Multi Unit spectroscopic Explorer (MUSE) is a second generation VLT panoramic integral-field spectrograph operating in the visible wavelength range. MUSE has field of 1 x arcmin<sup>2</sup> sampled at 0.2x0.2 arcsec<sup>2</sup> and assisted by ground layer adaptive optics system using four laser guide stars. simultaneous spectral range 0.465-0.93 μm, resolution R~3000. couples discovery potential large imaging device to measuring capabilities high-quality spectrograph, while taking...
MAORY is a post-focal adaptive optics module that forms part of the first light instrument suite for ELT. The main function to relay beam from ELT focal plane client while compensating effects atmospheric turbulence and other disturbances affecting wavefront scientific sources interest.
The introduction of Image Slicers in Astronomy has been growing rapidly the recent years. These optical devices allow simultaneous observation on same detector matrix two-dimensional sky maps and spectral decomposition light all their angular samples, therefore dramatically reducing times getting rid spectro-photometric variations atmosphere. Today implementation is planned various ground space telescopes, covering a domain ranging from blue to mid-IR wavelengths. Among such different...
The use of wavefront sensors (WFS) is nowadays fundamental in the field instrumental optics. This paper discusses principle an original and recently proposed new class WFS. Their consists evaluating slopes errors by means varying density filters placed into image plane tested optical system. device, sometimes called ‘optical differentiation WFS’ completed a digital data-processing system reconstructing from obtained slopes. Various luminous sources different wavelengths spectral widths can...
This paper describes a backward-gazing method for measuring the optomechanical errors of solar concentrating surfaces. It makes use four cameras placed near receiver and simultaneously recording images sun reflected by optical Simple data processing then allows reconstructing slope shape The originality is enforced generalized quad-cell formulas approximate mathematical relations between mirrors their wavefront in case sun-tracking heliostats at high-incidence angles. Numerical simulations...
The pointing and canting accuracies the surface shape of heliostats have a great influence on solar tower power plant efficiency. At industrial scale, one issues to solve is time efforts devoted adjust different mirrors faceted heliostats, which could take several months if current methods were used. Accurate control heliostat tracking requires complicated onerous devices. Thus, used quickly whole field are essential for rise technology with huge number heliostats. Wavefront detection widely...
Nulling interferometry is one of the most promising methods to study habitable extrasolar systems. Several projects, such as Darwin, TPF, Pegase, FKSI or Aladdin, are currently considered and supported by R&D programs. One main issues nulling feasibility a stable polychromatic null despite presence significant disturbances, induced vibrations, atmospheric turbulence on ground satellite drift for spaceborne missions. To reduce cost complexity whole system, it necessary optimize not only...
This paper presents a Fresnel diffraction analysis of classical Ronchi and reverse Hartmann tests. Simplified analytical expressions the intensity patterns observed by camera are established, allowing quantitative measurements wavefront slopes tested optical system. The wavefronts then reconstructed from their using double Fourier transform algorithm. optimization operational parameters system is discussed in view different quality criteria, including relative pupil shear contrast factors...
Stabilizing a nulling interferometer at nanometric level is the key issue to obtain deep null depths. The PERSEE breadboard has been designed study and optimize operation of cophased bench in most realistic disturbing environment space mission. This presentation focuses on current results bench. In terms metrology, we 0.33 nm rms for piston 60 mas tip/tilt. A Linear Quadratic Gaussian (LQG) control coupled with an unsupervised vibration identification allows us maintain that correction, even...
HARMONI is a first-light visible and near-IR integral field spectrograph of ESO's Extremely Large Telescope (ELT) which will sit on top Cerro Armazones, Chile. A Single Conjugate Adaptive Optics (SCAO) subsystem provide diffraction-limited spectro-images in Nyquist-sampled 0.61 x 0.86 arcsec view, with R=3000-20000 spectral resolution. Inside the instrument, High Contrast Module (HCM) could give ability to spectrally characterize young giant exoplanets (and disks) flux ratio down...