References of "Barillot, M"
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See detailExozodiacal discs with ALADDIN: how faint can we detect them?
Absil, Olivier ULg; Coudé Du Foresto; Barillot, M. et al

in Spinoglio, L.; Epchtein, N. (Eds.) 3rd ARENA Conference: An Astronomical Observatory at CONCORDIA (Dome C, Antarctica) (2010)

In this paper, we describe the expected performance of ALADDIN, a nulling interferometer project optimised for operation at Dome C. After reviewing the main atmospheric parameters pertaining to infrared ... [more ▼]

In this paper, we describe the expected performance of ALADDIN, a nulling interferometer project optimised for operation at Dome C. After reviewing the main atmospheric parameters pertaining to infrared interferometry on the high Antarctic plateau, we shortly describe the ALADDIN instrument and compute its estimated performance in terms of the smallest exozodiacal dust disc density that can be detected. Our estimations are based on a thorough end-to-end software simulator previously developed for the GENIE nulling interferometer project at VLTI. We then propose a possible mission scenario, where the southern target stars of future exo-Earth characterisation missions can be surveyed for the presence of bright exozodiacal discs (>50 zodi) within one winter-over at Concordia. [less ▲]

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See detailGENIE: a Ground-Based European Nulling Instrument at ESO Very Large Telescope Interferometer
Gondoin, P.; den Hartog, R.; Fridlund, M. et al

in Richichi, A.; Delplancke, F.; Paresce, F. (Eds.) et al The Power of Optical/IR Interferometry: Recent Scientific Results and 2nd Generation Instrumentation (2008)

Darwin is one of the most challenging space projects ever considered by the European Space Agency (ESA). Its principal objectives are to detect Earth-like planets around nearby stars, to analyze the ... [more ▼]

Darwin is one of the most challenging space projects ever considered by the European Space Agency (ESA). Its principal objectives are to detect Earth-like planets around nearby stars, to analyze the composition of their atmospheres and to assess their ability to sustain life as we know it. Darwin is conceived as a space ``nulling interferometer'' which makes use of on-axis destructive interferences to extinguish the stellar light while keeping the off-axis signal of the orbiting planet. Within the frame of the Darwin program, definition studies of a Ground based European Nulling Interferometry Experiment, called GENIE, were completed in 2005. This instrument built around the Very Large Telescope Interferometer (VLTI) in Paranal will test some of the key technologies required for the Darwin Infrared Space Interferometer. GENIE will operate in the L' band around 3.8 microns as a single Bracewell nulling interferometer using either two Auxiliary Telescopes (ATs) or two 8m Unit Telescopes (UTs). Its science objectives include the detection and characterization of dust disks and low-mass companions around nearby stars. [less ▲]

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See detailNulling interferometry: performance comparison between Antarctica and other ground-based sites
Absil, Olivier ULg; Coudé Du Foresto, V.; Barillot, M. et al

in Astronomy and Astrophysics (2007), 475

Context: Detecting the presence of circumstellar dust around nearby solar-type main sequence stars is an important pre-requisite for the design of future life-finding space missions such as ESA's Darwin ... [more ▼]

Context: Detecting the presence of circumstellar dust around nearby solar-type main sequence stars is an important pre-requisite for the design of future life-finding space missions such as ESA's Darwin or NASA's Terrestrial Planet Finder (TPF). The high Antarctic plateau may provide appropriate conditions to perform such a survey from the ground. Aims: We investigate the performance of a nulling interferometer optimised for the detection of exozodiacal discs at Dome C, on the high Antarctic plateau, and compare it to the expected performance of similar instruments at temperate sites. Methods: Based on the currently available measurements of the atmospheric turbulence characteristics at Dome C, we adapt the GENIEsim software (Absil et al. 2006, A&A, 448, 787) to simulate the performance of a nulling interferometer on the high Antarctic plateau. To feed a realistic instrumental configuration into the simulator, we propose a conceptual design for ALADDIN, the Antarctic L-band Astrophysics Discovery Demonstrator for Interferometric Nulling. We assume that this instrument can be placed above the 30-m thick boundary layer, where most of the atmospheric turbulence originates. Results: We show that an optimised nulling interferometer operating on a pair of 1-m class telescopes located 30 m above the ground could achieve a better sensitivity than a similar instrument working with two 8-m class telescopes at a temperate site such as Cerro Paranal. The detection of circumstellar discs about 20 times as dense as our local zodiacal cloud seems within reach for typical Darwin/TPF targets in an integration time of a few hours. Moreover, the exceptional turbulence conditions significantly relax the requirements on real-time control loops, which has favourable consequences on the feasibility of the nulling instrument. Conclusions: The perspectives for high dynamic range, high angular resolution infrared astronomy on the high Antarctic plateau look very promising. [less ▲]

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See detailProspects for Nulling Interferometry from Antarctica
Coudé Du Foresto, V.; Absil, Olivier ULg; Barillot, M. et al

Poster (2007, June 01)

The high Antarctic plateau is a very unique environment whose main characteristics make it a premier site for high angular resolution, high dynamic range observations at infrared wavelengths. This is due ... [more ▼]

The high Antarctic plateau is a very unique environment whose main characteristics make it a premier site for high angular resolution, high dynamic range observations at infrared wavelengths. This is due to a combination of cold temperatures (low emissivity), dry air (infrared transparency), and a night time atmospheric turbulence which is concentrated in the first ~30m near the ground (which results in a large isoplanatic angle). Above that turbulent layer (a location that can be reached either by support structures or tethered balloons), the free air seeing is both exceptionally benign and slow. There, simulations show that a small dedicated interferometer (two 1m-class telescopes) equipped with a nuller instrument performs better than the same instrument behind 8m-class telescopes on a temperate site. It can characterize the distribution of dust emission around nearby main sequence stars, a necessary precursor science for Darwin and TPF-I. The nature of the site, intermediate between ground and space both in potential and technical challenge, adds particular relevance to the demonstration of nulling for a space mission. [less ▲]

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See detailALADDIN: an optimized nulling ground-based demonstrator for DARWIN
Coudé du Foresto, V.; Absil, Olivier ULg; Swain, M. et al

in Monnier, John; Schöller, Markus; Danchi, William (Eds.) Advances in Stellar Interferometry (2006, July 01)

The ESA Darwin space mission will require a ground based precursor to i/ demonstrate nulling interferometry in an operational context and ii/ carry out some precursor science, such as the characterization ... [more ▼]

The ESA Darwin space mission will require a ground based precursor to i/ demonstrate nulling interferometry in an operational context and ii/ carry out some precursor science, such as the characterization of the level of exozodiacal light around the main Darwin targets. These are the stated objectives of the GENIE nulling instrument that was studied for the VLTI. We argue here that the same objectives can be met in a more efficient way by an antarctic-based nulling experiment. The ALADDIN mission concept is an integrated L-band nulling breadboard with relatively modest collectors (1m) and baseline (40m). Because of its privileged location, this is suffcient to achieve a sensitivity (in terms of detectable zodi levels) which is 1.6 to 3.5 times better than GENIE at the VLTI, bringing it below the 20-zodi threshold value identified to carry out the Darwin precursor science. The integrated design enables top-level optimization and full access to the light collectors for the duration of the experiment, while reducing the complexity of the nulling breadboard. [less ▲]

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See detailALADDIN: a DARWIN Pathfinder Mission on the Antarctic Plateau
Coudé Du Foresto, V.; Absil, Olivier ULg; Barillot, M.

in Coudé du Foresto, Vincent; Rouan, Daniel; Rousset, Gérard (Eds.) Visions for Infrared Astronomy (2006, March)

We propose an innovative concept for a DARWIN pathfinder experiment. It involves an integrated nulling interferometer of relatively modest dimensions (two 1 m class collectors on a 40 m truss), which ... [more ▼]

We propose an innovative concept for a DARWIN pathfinder experiment. It involves an integrated nulling interferometer of relatively modest dimensions (two 1 m class collectors on a 40 m truss), which would take advantage of a privileged location (at Dome C on the Antarctic plateau) to perform better than a nulling instrument on a large interferometer (such as GENIE at the VLTI). [less ▲]

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