References of "Cassaing, F"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailPEGASE, an infrared interferometer to study stellar environments and low mass companions around nearby stars
Ollivier, M.; Absil, Olivier ULg; Allard, F. et al

in Experimental Astronomy (2009), 23

PEGASE is a mission dedicated to the exploration of the environment (including habitable zone) of young and solar-type stars (particularly those in the DARWIN catalogue) and the observation of low mass ... [more ▼]

PEGASE is a mission dedicated to the exploration of the environment (including habitable zone) of young and solar-type stars (particularly those in the DARWIN catalogue) and the observation of low mass companions around nearby stars. It is a space interferometer project composed of three free flying spacecraft, respectively featuring two 40 cm siderostats and a beam combiner working in the visible and near infrared. It has been proposed to ESA as an answer to the first ``Cosmic Vision'' call for proposals, as an M mission. The concept also enables full-scale demonstration of space nulling interferometry operation for DARWIN. [less ▲]

Detailed reference viewed: 64 (9 ULg)
Full Text
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 ▲]

Detailed reference viewed: 7 (0 ULg)
Full Text
See detailPegase: a space-based nulling interferometer
Le Duigou, J. M.; Ollivier, M.; Léger, A. et al

in Mather, John C.; MacEwen, Howard A.; de Graauw, Mattheus W. M. (Eds.) Space Telescopes and Instrumentation I: Optical, Infrared, and Millimeter (2006, July 01)

The space based mission Pegase was proposed to CNES in the framework of its call for scientific proposals for formation flying missions. This paper presents a summary of the phase-0 performed in 2005. The ... [more ▼]

The space based mission Pegase was proposed to CNES in the framework of its call for scientific proposals for formation flying missions. This paper presents a summary of the phase-0 performed in 2005. The main scientific goal is the spectroscopy of hot Jupiters (Pegasides) and brown dwarfs from 2.5 to 5 mum. The mission can extend to other objectives such as the exploration of the inner part of protoplanetary disks, the study of dust clouds around AGN,... The instrument is basically a two-aperture (D=40 cm) interferometer composed of three satellites, two siderostats and one beam-combiner. The formation is linear and orbits around L2, pointing in the anti-solar direction within a +/-30° cone. The baseline is adjustable from 50 to 500 m in both nulling and visibility measurement modes. The angular resolution ranges from 1 to 20 mas and the spectral resolution is 60. In the nulling mode, a 2.5 nm rms stability of the optical path difference (OPD) and a pointing stability of 30 mas rms impose a two level control architecture. It combines control loops implemented at satellite level and control loops operating inside the payload using fine mechanisms. According to our preliminary study, this mission is feasible within an 8 to 9 years development plan using existing or slightly improved space components, but its cost requires international cooperation. Pegase could be a valuable Darwin/TPF-I pathfinder, with a less demanding, but still ambitious, technological challenge and a high associated scientific return. [less ▲]

Detailed reference viewed: 12 (0 ULg)
Full Text
See detailPEGASE: a DARWIN/TPF pathfinder
Ollivier, M.; Le Duigou, J.-M.; Mourard, D. et al

in Aime, C.; Vakili, F. (Eds.) Direct Imaging of Exoplanets: Science & Techniques (2006)

The space mission PEGASE, proposed to the CNES (Centre National d'Etudes Spatiales = French Space Agency) in the framework of its call for scientific proposals : "formation flying missions", is a 2 ... [more ▼]

The space mission PEGASE, proposed to the CNES (Centre National d'Etudes Spatiales = French Space Agency) in the framework of its call for scientific proposals : "formation flying missions", is a 2-aperture interferometer, composed by 3 free flying satellites (2 siderostats and 1 beam combiner), allowing baselines from 50 to 500 m in both nulling and visibility modes. With an angular resolution of a few mas and a spectral resolution of several tens in the spectral range 2.5-5 microns, PEGASE has several goals:science : spectroscopy of hot jupiters (Pegasides) and brown dwarves, exploration of the inner part of protoplanetary diskstechnology : validation in real space conditions of formation flying, nulling and visibility interferometry concepts.PEGASE has been studied at a 0-level. In this paper, we summarize the scientific program and associated technological and mission trade-off coming from this 0-level study. We also discuss how PEGASE can be considered as a TPF/DARWIN pathfinder in an international roadmap towards more complex space interferometry missions such as DARWIN/TPF. [less ▲]

Detailed reference viewed: 9 (0 ULg)
See detailPEGASE... towards DARWIN
Ollivier, M.; Le Duigou, J.-M.; Mourard, D. et al

in Casoli, F.; Contini, T.; Hameury, J.-M. (Eds.) et al SF2A-2005: Semaine de l'Astrophysique Francaise (2005, December 01)

The space mission PEGASE, proposed to CNES in the framework of its call for scientific proposals on "formation flying", is a 2-aperture interferometer, composed by 3 free flying satellites. With an ... [more ▼]

The space mission PEGASE, proposed to CNES in the framework of its call for scientific proposals on "formation flying", is a 2-aperture interferometer, composed by 3 free flying satellites. With an angular resolution of a few mas and a spectral resolution of several tens in the spectral range 2.5-5 mum, PEGASE has several goals: - science: spectroscopy of hot jupiters (Pegasides) and brown dwarves, exploration of the inner part of protoplanetary disks; - technology: validation in real space conditions of formation flying, nulling and visibility interferometry concepts. PEGASE, presently in 0-phase study takes place in the context of DARWIN preparation. We detail in this paper the present situation of this project [less ▲]

Detailed reference viewed: 5 (0 ULg)
See detailThe PEGASE project: characterisation of "Pegasi planets" and Brown Dwarfs
Baudoz, P.; Rouan, D.; Schneider, J. et al

in Combes, F.; Barret, D.; Contini, T. (Eds.) et al SF2A-2004: Semaine de l'Astrophysique Francaise (2004, December 01)

I will present the PEGASE project proposed within the framework of the CNES call for idea on flights in formation. This ambitious project, gathering a dozen laboratories, proposes an interferometry ... [more ▼]

I will present the PEGASE project proposed within the framework of the CNES call for idea on flights in formation. This ambitious project, gathering a dozen laboratories, proposes an interferometry mission in infrared I(1.5 to 6 µm) with spectroscopic capabilities. The bases of the interferometer will reach up to 500m, giving to PEGASE a resolution higher than the milli-arcsecond. The interferometric recombination includes a very simple mode, measurement of the visibility by excursion of the optical path difference and a mode in black fringe or nulling. The very high angular resolution of the instrument and high dynamical range with the nulling mode will allow to consider exciting scientific objectives: the characterization of Pegasids or hot Jupiters, the study of the internal structure and the atmospheres of brown dwarfs and the analysis of the internal areas of proto-planetary disks. I will first of all describe the basic configuration of the mission and will show that its simplicity ensures the feasibility of the project. I will explain then the relevance of such an instrument for the characterization of Pegasids. I will detail finally the various possible technical options to be attached to the initial version, in order to increase the effectiveness of the mission and to extend its scientific objectives. [less ▲]

Detailed reference viewed: 3 (0 ULg)