References of "Boccaletti, Anthony"
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See detailDynamical Evidence of a Spiral Arm-driving Planet in the MWC 758 Protoplanetary Disk
Ren, Bin; Dong, Ruobing; van Holstein, Rob G. et al

in Astrophysical Journal (2020), 898

More than a dozen young stars host spiral arms in their surrounding protoplanetary disks. The excitation mechanisms of such arms are under debate. The two leading hypotheses—companion-disk interaction and ... [more ▼]

More than a dozen young stars host spiral arms in their surrounding protoplanetary disks. The excitation mechanisms of such arms are under debate. The two leading hypotheses—companion-disk interaction and gravitational instability (GI)—predict distinct motion for spirals. By imaging the MWC 758 spiral arm system at two epochs spanning ∼5 yr using the SPHERE instrument on the Very Large Telescope, we test the two hypotheses for the first time. We find that the pattern speeds of the spirals are not consistent with the GI origin. Our measurements further evince the existence of a faint "missing planet" driving the disk arms. The average spiral pattern speed is 0°22 ± 0°03 yr[SUP]-1[/SUP], pointing to a driver at ${172}_{-14}^{+18}$ au around a 1.9 M[SUB]☉[/SUB] central star if it is on a circular orbit. In addition, we witness time-varying shadowing effects on a global scale that are likely originating from an inner disk. [less ▲]

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See detailESA Voyage 2050 White Paper: Detecting life outside our solar system with a large high-contrast-imaging mission
Snellen, Ignas; Albrecht, Simon; Anglada-Escude, Guillem et al

E-print/Working paper (2019)

In this white paper, we recommend the European Space Agency plays a proactive role in developing a global collaborative effort to construct a large high-contrast imaging space telescope, e.g. as currently ... [more ▼]

In this white paper, we recommend the European Space Agency plays a proactive role in developing a global collaborative effort to construct a large high-contrast imaging space telescope, e.g. as currently under study by NASA. Such a mission will be needed to characterize a sizable sample of temperate Earth-like planets in the habitable zones of nearby Sun-like stars and to search for extraterrestrial biological activity. We provide an overview of relevant European expertise, and advocate ESA to start a technology development program towards detecting life outside the Solar system. <P /> [less ▲]

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See detailFirst resolved observations of a highly asymmetric debris disc around HD 160305 with VLT/SPHERE
Perrot, Clément; Thebault, Philippe; Lagrange, Anne-Marie et al

in Astronomy and Astrophysics (2019), 626

Context. Direct imaging of debris discs gives important information about their nature, their global morphology, and allows us to identify specific structures possibly in connection with the presence of ... [more ▼]

Context. Direct imaging of debris discs gives important information about their nature, their global morphology, and allows us to identify specific structures possibly in connection with the presence of gravitational perturbers. It is the most straightforward technique to observe planetary systems as a whole. <BR /> Aims: We present the first resolved images of the debris disc around the young F-type star HD 160305, detected in scattered light using the VLT/SPHERE instrument in the near infrared. <BR /> Methods: We used a post-processing method based on angular differential imaging and synthetic images of debris discs produced with a disc modelling code (GRaTer) to constrain the main characteristics of the disc around HD 160305. All of the point sources in the field of the IRDIS camera were analysed with an astrometric tool to determine whether they are bound objects or background stars. <BR /> Results: We detect a very inclined ( 82°) ring-like debris disc located at a stellocentric distance of about 86 au (deprojected width 27 au). The disc displays a brightness asymmetry between the two sides of the major axis, as can be expected from scattering properties of dust grains. We derive an anisotropic scattering factor g > 0.5. A second right-left asymmetry is also observed with respect to the minor axis. We measure a surface brightness ratio of 0.73 ± 0.18 between the bright and the faint sides. Because of the low signal-to-noise ratio (S/N) of the images we cannot easily discriminate between several possible explanations for this left-right asymmetry, such as perturbations by an unseen planet, the aftermath of the breakup of a massive planetesimal, or the pericenter glow effect due to an eccentric ring. Two epochs of observations allow us to reject the companionship hypothesis for the 15 point sources present in the field. <P />The reduced images (FITS files) are only available at the CDS via anonymous ftp to <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A> (ftp://130.79.128.5) or via <A href="http://cdsarc.u-strasbg.fr/viz- bin/qcat?J/A+A/626/A95">http://cdsarc.u-strasbg.fr/viz- bin/qcat?J/A+A/626/A95</A>Based on observations made with ESO Telescopes at the Paranal Observatory under programs ID 95.C-0298 and 97.C-0865.Note to the reader: The name of the author "Jean-Charles Ausgereau" was a mistake and has been corrected in "Jean-Charles Augereau" on 3 July 2019. [less ▲]

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See detailModeling Debris Disk Evolution
Gaspar, Andras; Apai, Dániel; Augereau, Jean-Charles et al

in Bulletin of the American Astronomical Society (2019), 51(3), 69

Understanding the formation, evolution, and architectures of planetary systems requires detailed knowledge of their components. Debris disks provide a means with which we can study them. The next decade ... [more ▼]

Understanding the formation, evolution, and architectures of planetary systems requires detailed knowledge of their components. Debris disks provide a means with which we can study them. The next decade will deliver a wealth of new information on the nearest systems. Parallel advances in modeling will be necessary to interpret these new datasets. [less ▲]

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See detailKey Technologies for the Wide Field Infrared Survey Telescope Coronagraph Instrument
Bailey, Vanessa P.; Armus, Lee; Balasubramanian, Bala et al

E-print/Working paper (2019)

The Wide Field Infrared Survey Telescope (WFIRST) Coronagraph Instrument (CGI) is a high-contrast imager and integral field spectrograph that will enable the study of exoplanets and circumstellar disks at ... [more ▼]

The Wide Field Infrared Survey Telescope (WFIRST) Coronagraph Instrument (CGI) is a high-contrast imager and integral field spectrograph that will enable the study of exoplanets and circumstellar disks at visible wavelengths. Ground-based high-contrast instrumentation has fundamentally limited performance at small working angles, even under optimistic assumptions for 30m-class telescopes. There is a strong scientific driver for better performance, particularly at visible wavelengths. Future flagship mission concepts aim to image Earth analogues with visible light flux ratios of more than 10^10. CGI is a critical intermediate step toward that goal, with a predicted 10^8-9 flux ratio capability in the visible. CGI achieves this through improvements over current ground and space systems in several areas: (i) Hardware: space-qualified (TRL9) deformable mirrors, detectors, and coronagraphs, (ii) Algorithms: wavefront sensing and control; post- processing of integral field spectrograph, polarimetric, and extended object data, and (iii) Validation of telescope and instrument models at high accuracy and precision. This white paper, submitted to the 2018 NAS Exoplanet Science Strategy call, describes the status of key CGI technologies and presents ways in which performance is likely to evolve as the CGI design matures. <P /> [less ▲]

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See detailThree Years of SPHERE: The Latest View of the Morphology and Evolution of Protoplanetary Discs
Garufi, Antonio; Benisty, Myriam; Stolker, Tomas et al

in Messenger (2017), 169

Spatially resolving the immediate surroundings of young stars is a key challenge for the planet formation community. SPHERE on the VLT represents an important step forward by increasing the opportunities ... [more ▼]

Spatially resolving the immediate surroundings of young stars is a key challenge for the planet formation community. SPHERE on the VLT represents an important step forward by increasing the opportunities offered by optical or near-infrared imaging instruments to image protoplanetary discs. The Guaranteed Time Observation Disc team has concentrated much of its efforts on polarimetric differential imaging, a technique that enables the efficient removal of stellar light and thus facilitates the detection of light scattered by the disc within a few au from the central star. These images reveal intriguing complex disc structures and diverse morphological features that are possibly caused by ongoing planet formation in the disc. An overview of the recent advances enabled by SPHERE is presented. <P /> [less ▲]

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See detailThe SHARDDS survey: First resolved image of the HD 114082 debris disk in the Lower Centaurus Crux with SPHERE
Wahhaj, Zahed; Milli, Julien; Kennedy, Grant et al

in Astronomy and Astrophysics (2016), 596

We present the first resolved image of the debris disk around the 16 ± 8 Myr old star, HD 114082. The observation was made in the H-band using the SPHERE instrument. The star is at a distance of 92 ± 6 pc ... [more ▼]

We present the first resolved image of the debris disk around the 16 ± 8 Myr old star, HD 114082. The observation was made in the H-band using the SPHERE instrument. The star is at a distance of 92 ± 6 pc in the Lower Centaurus Crux association. Using a Markov chain Monte Carlo analysis, we determined that the debris is likely in the form of a dust ring with an inner edge of 27.7[SUP]+2.8[/SUP][SUB]-3.5[/SUB] au, position angle -74.3°[SUP]+0.5[/SUP][SUB]-1.5[/SUB], and an inclination with respect to the line of sight of 6.7°[SUP]+3.8[/SUP][SUB]-0.4[/SUB]. The disk imaged in scattered light has a surface density that is declining with radius of r[SUP]-4[/SUP], which is steeper than expected for grain blowout by radiation pressure. We find only marginal evidence (2σ) of eccentricity and rule out planets more massive than 1.0 M[SUB]Jup[/SUB] orbiting within 1 au of the inner edge of the ring, since such a planet would have disrupted the disk. The disk has roughly the same fractional disk luminosity (L[SUB]disk[/SUB]/L[SUB]∗[/SUB] = 3.3 × 10[SUP]-3[/SUP]) as HR 4796 A and β Pictoris, however it was not detected by previous instrument facilities most likely because of its small angular size (radius 0.4''), low albedo ( 0.2), and low scattering efficiency far from the star due to high scattering anisotropy. With the arrival of extreme adaptive optics systems, such as SPHERE and GPI, the morphology of smaller, fainter, and more distant debris disks are being revealed, providing clues to planet-disk interactions in young protoplanetary systems. The reduced images are only available at the CDS via anonymous ftp to <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A> (<A href="http://130.79.128.5">http://130.79.128.5</A>) or via <A href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/596/L4">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/596/L4</A> [less ▲]

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See detailDetection of Sharp Symmetric Features in the Circumbinary Disk around AK Sco
Janson, Markus; Thalmann, Christian; Boccaletti, Anthony et al

in Astrophysical Journal (2016), 816(1), 1

The Search for Planets Orbiting Two Stars survey aims to study the formation and distribution of planets in binary systems by detecting and characterizing circumbinary planets and their formation ... [more ▼]

The Search for Planets Orbiting Two Stars survey aims to study the formation and distribution of planets in binary systems by detecting and characterizing circumbinary planets and their formation environments through direct imaging. With the SPHERE Extreme Adaptive Optics instrument, a good contrast can be achieved even at small (<300 mas) separations from bright stars, which enables studies of planets and disks in a separation range that was previously inaccessible. Here, we report the discovery of resolved scattered light emission from the circumbinary disk around the well-studied young double star AK Sco, at projected separations in the ̃13-40 AU range. The sharp morphology of the imaged feature is surprising, given the smooth appearance of the disk in its spectral energy distribution. We show that the observed morphology can be represented either as a highly eccentric ring around AK Sco, or as two separate spiral arms in the disk, wound in opposite directions. The relative merits of these interpretations are discussed, as well as whether these features may have been caused by one or several circumbinary planets interacting with the disk. <P />Based on observations collected at the European Southern Observatory, Chile, under observing program 095.C-0346(B). [less ▲]

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See detailFast-moving features in the debris disk around AU Microscopii
Boccaletti, Anthony; Thalmann, Christian; Lagrange, Anne-Marie et al

in Nature (2015), 526

In the 1980s, excess infrared emission was discovered around main- sequence stars; subsequent direct-imaging observations revealed orbiting disks of cold dust to be the source. These `debris disks' were ... [more ▼]

In the 1980s, excess infrared emission was discovered around main- sequence stars; subsequent direct-imaging observations revealed orbiting disks of cold dust to be the source. These `debris disks' were thought to be by-products of planet formation because they often exhibited morphological and brightness asymmetries that may result from gravitational perturbation by planets. This was proved to be true for the β Pictoris system, in which the known planet generates an observable warp in the disk. The nearby, young, unusually active late-type star AU Microscopii hosts a well-studied edge-on debris disk; earlier observations in the visible and near-infrared found asymmetric localized structures in the form of intensity variations along the midplane of the disk beyond a distance of 20 astronomical units. Here we report high- contrast imaging that reveals a series of five large-scale features in the southeast side of the disk, at projected separations of 10-60 astronomical units, persisting over intervals of 1-4 years. All these features appear to move away from the star at projected speeds of 4-10 kilometres per second, suggesting highly eccentric or unbound trajectories if they are associated with physical entities. The origin, localization, morphology and rapid evolution of these features are difficult to reconcile with current theories. [less ▲]

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See detailSPICES: A Mission Concept to Characterize Long Period Planets from Giants to Super-Earths
Boccaletti, Anthony; Maire, Anne-Lise ULiege; Galicher, Raphaël et al

in IAUS 293: Formation, Detection, and Characterization of Extrasolar Habitable Planets (2014, April 01)

SPICES (Spectro-Polarimetric Imaging and Characterization of Exoplanetary Systems) was proposed in 2010 for a five-year M-class mission in the context of ESA Cosmic Vision. Its purpose is to image and ... [more ▼]

SPICES (Spectro-Polarimetric Imaging and Characterization of Exoplanetary Systems) was proposed in 2010 for a five-year M-class mission in the context of ESA Cosmic Vision. Its purpose is to image and characterize long-period extrasolar planets located at several AUs (0.5-10 AU) from nearby stars (<25 pc) with masses ranging from a few Jupiter masses down to super-Earths (~2 Earth radii, ~10 M[SUB]⊕[/SUB]), possibly habitable. In addition, circumstellar disks as faint as a few times the zodiacal light in the Solar System can be studied. SPICES is based on a 1.5-m off-axis telescope and can perform spectro-polarimetric measurements in the visible (450 - 900 nm) at a spectral resolution of about 40. This paper summarizes the top science program and the choices made to conceive the instrument. The performance is illustrated for a few emblematic cases. <P /> [less ▲]

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See detailAtmospheric Characterization of Cold Exoplanets Using a 1.5-m Space Coronagraph
Maire, Anne-Lise ULiege; Galicher, Raphaël; Boccaletti, Anthony et al

in IAUS 293: Formation, Detection, and Characterization of Extrasolar Habitable Planets (2014, April 01)

We present numerical results of the science performance of the SPICES mission, which aims to characterize the spectro-polarimetric properties of cold exoplanets and circumstellar disks in the visible. We ... [more ▼]

We present numerical results of the science performance of the SPICES mission, which aims to characterize the spectro-polarimetric properties of cold exoplanets and circumstellar disks in the visible. We focus on the instrument ability to retrieve the spectral signatures of molecular species, clouds and surface of super-Earths in the habitable zone of solar-type stars. Considering realistic reflected planet spectra and instrument limitation, we show that SPICES could analyse the atmosphere and surface of a few super-Earths within 5 pc of the Sun. <P /> [less ▲]

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See detailSearch for cool extrasolar giant planets combining coronagraphy, spectral and angular differential imaging
Maire, Anne-Lise ULiege; Boccaletti, Anthony; Rameau, Julien et al

in IAUS 299: Exploring the Formation and Evolution of Planetary Systems (2014, January 01)

Spectral differential imaging (SDI) is part of the observing strategy of current and on-going high-contrast imaging instruments on ground-based telescopes. Although it improves the star light rejection ... [more ▼]

Spectral differential imaging (SDI) is part of the observing strategy of current and on-going high-contrast imaging instruments on ground-based telescopes. Although it improves the star light rejection, SDI attenuates the signature of off-axis companions to the star, just like angular differential imaging (ADI). However, the attenuation due to SDI has the peculiarity of being dependent on the spectral properties of the companions. To date, no study has investigated these effects. Our team is addressing this problem based on data from a direct imaging survey of 16 stars combining the phase-mask coronagraph, the SDI and the ADI modes of VLT/NaCo. The objective of the survey is to search for cool (Teff<1000-1300 K) giant planets at separations of 5-10 AU orbiting young, nearby stars (<200 Myr, <25 pc). The data analysis did not yield any detections. As for the estimation of the sensivity limits of SDI-processed images, we show that it requires a different analysis than that used in ADI-based surveys. Based on a method using the flux predictions of evolutionary models and avoiding the estimation of contrast, we determine directly the mass sensivity limits of the survey for the ADI processing alone and with the combination of SDI and ADI. We show that SDI does not systematically improve the sensitivity due to the spectral properties and self-subtraction of point sources. <P /> [less ▲]

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See detailDetection and spectral characterization of mature planetary systems using space-based high-contrast imaging
Maire, Anne-Lise ULiege; Boccaletti, Anthony; Schneider, Jean-Louis et al

Conference (2014)

Several projects of space high-contrast imaging telescopes are currently under study for the detection and spectral characterization (R∼50) of mature planetary systems at visible wavelengths, from gas ... [more ▼]

Several projects of space high-contrast imaging telescopes are currently under study for the detection and spectral characterization (R∼50) of mature planetary systems at visible wavelengths, from gas giant planets to super-Earths. We present the science program, instrument concept, and simulations of science performance of one of these projects, SPICES, which was submitted to the M3 ESA Cosmic Vision call. Such an instrument would be able to spectrally characterize ∼300 planetary systems within 15 pc of the Sun. [less ▲]

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See detailSmall-angle, high-contrast exoplanet imaging with the L-band AGPM vector vortex coronagraph now offered at the VLT
Mawet, Dimitri; Absil, Olivier ULiege; Milli, Julien et al

in Shaklan, Stuart (Ed.) Techniques and Instrumentation for Detection of Exoplanets VI (2013, September 26)

In November 2012, we installed an L-band annular groove phase mask (AGPM) vector vortex coronagraph (VVC) inside NACO, the adaptive optics camera of ESO's Very Large Telescope. The mask, made out of ... [more ▼]

In November 2012, we installed an L-band annular groove phase mask (AGPM) vector vortex coronagraph (VVC) inside NACO, the adaptive optics camera of ESO's Very Large Telescope. The mask, made out of diamond subwavelength gratings has been commissioned, science qualified, and is now offered to the community. Here we report ground-breaking on-sky performance levels in terms of contrast, inner working angle, and discovery space. This new practical demonstration of the VVC, coming a few years after Palomar's and recent record-breaking lab experiments in the visible (E. Serabyn et al. 2013, these proceedings), shows once again that this new-generation coronagraph has reached a high level of maturity. [less ▲]

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See detailLaboratory demonstration of a mid-infrared AGPM vector vortex coronagraph
Delacroix, Christian ULiege; Absil, Olivier ULiege; Forsberg, Pontus et al

in Astronomy and Astrophysics (2013), 553

Coronagraphy is a powerful technique to achieve high contrast imaging and hence to image faint companions around bright targets. Various concepts have been used in the visible and near-infrared regimes ... [more ▼]

Coronagraphy is a powerful technique to achieve high contrast imaging and hence to image faint companions around bright targets. Various concepts have been used in the visible and near-infrared regimes, while coronagraphic applications in the mid-infrared remain nowadays largely unexplored. Vector vortex phase masks based on concentric subwavelength gratings show great promise for such applications. We aim at producing and validating the first high-performance broadband focal plane phase mask coronagraphs for applications in the mid-infrared regime, and in particular the L band with a fractional bandwidth of ~16% (3.5-4.1 \mu m). Based on rigorous coupled wave analysis, we designed an annular groove phase mask (AGPM) producing a vortex effect in the L band, and etched it onto a series of diamond substrates. The grating parameters were measured by means of scanning electron microscopy. The resulting components were then tested on a mid-infrared coronagraphic test bench. A broadband raw null depth of 2 x 10^{-3} was obtained for our best L-band AGPM after only a few iterations between design and manufacturing. This corresponds to a raw contrast of about 6 x 10^{-5} (10.5 mag) at 2\lambda/D. This result is fully in line with our projections based on rigorous coupled wave analysis modeling, using the measured grating parameters. The sensitivity to tilt and focus has also been evaluated. After years of technological developments, mid-infrared vector vortex coronagraphs finally become a reality and live up to our expectations. Based on their measured performance, our L-band AGPMs are now ready to open a new parameter space in exoplanet imaging at major ground-based observatories. [less ▲]

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See detailSPICES a small space coronagraph to characterize giant and telluric planets in reflected light
Boccaletti, Anthony; Maire, Anne-Lise ULiege; Galicher, Raphaël et al

in Hot Planets and Cool Stars (2013, April 01)

SPICES (Spectro-Polarimetric Imaging and Characterization of Exoplanetary Systems) was proposed in 2010 for a a five-year M-class mission in the context of ESA Cosmic Vision. Its purpose is to image and ... [more ▼]

SPICES (Spectro-Polarimetric Imaging and Characterization of Exoplanetary Systems) was proposed in 2010 for a a five-year M-class mission in the context of ESA Cosmic Vision. Its purpose is to image and characterize long-period extrasolar planets located at several AUs (0.5-10 AU) from nearby stars (<25 pc) with masses ranging from a few Jupiter masses down to Super-Earths (̃2 Earth radii, ̃10M[SUB]⊕[/SUB]), possibly habitable. In addition, circumstellar disks as faint as a few times the zodiacal light in the Solar System can be studied. SPICES is based on a 1.5-m off-axis telescope and can perform spectro-polarimetric measurements in the visible (450-900 nm) at a spectral resolution of about 40. This paper summarizes the top science program and the choices made to conceive the instrument. The performance is illustrated for a few emblematic cases. <P /> [less ▲]

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See detailSPICES: spectro-polarimetric imaging and characterization of exoplanetary systems. From planetary disks to nearby Super Earths
Boccaletti, Anthony; Schneider, Jean; Traub, Wes et al

in Experimental Astronomy (2012), 34

SPICES (Spectro-Polarimetric Imaging and Characterization of Exoplanetary Systems) is a five-year M-class mission proposed to ESA Cosmic Vision. Its purpose is to image and characterize long-period ... [more ▼]

SPICES (Spectro-Polarimetric Imaging and Characterization of Exoplanetary Systems) is a five-year M-class mission proposed to ESA Cosmic Vision. Its purpose is to image and characterize long-period extrasolar planets and circumstellar disks in the visible (450-900 nm) at a spectral resolution of about 40 using both spectroscopy and polarimetry. By 2020/2022, present and near-term instruments will have found several tens of planets that SPICES will be able to observe and study in detail. Equipped with a 1.5 m telescope, SPICES can preferentially access exoplanets located at several AUs (0.5-10 AU) from nearby stars (<25 pc) with masses ranging from a few Jupiter masses to Super Earths (̃2 Earth radii, ̃10 M[SUB]⊕[/SUB]) as well as circumstellar disks as faint as a few times the zodiacal light in the Solar System. [less ▲]

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See detailAtmospheric characterization of cold exoplanets with a 1.5-m space coronagraph
Maire, Anne-Lise ULiege; Galicher, Raphaël; Boccaletti, Anthony et al

in Space Telescopes and Instrumentation 2012: Optical, Infrared, and Millimeter Wave (2012, September 01)

Several small space coronagraphs have been proposed to characterize cold exoplanets in reflected light. Studies have mainly focused on technical feasibility because of the huge star/planet flux ratio to ... [more ▼]

Several small space coronagraphs have been proposed to characterize cold exoplanets in reflected light. Studies have mainly focused on technical feasibility because of the huge star/planet flux ratio to achieve in the close-in stellar environment (10[SUP]8[/SUP]-10[SUP]10[/SUP] at 0.2"). However, the main interest of such instruments, the analysis of planet properties, has remained highly unexplored so far. We performed numerical simulations to assess the ability of a small space coronagraph to retrieve spectra of mature Jupiters, Neptunes and super-Earths under realistic assumptions. We describe our assumptions: exoplanetary atmosphere models, instrument numerical simulation and observing conditions. Then, we define a criterion and use it to determine the required exposure times to measure several planet parameters from their spectra (separation, metallicity, cloud and surface coverages) for particular cases. Finally, we attempt to define a parameter space of the potential targets. In the case of a solar-type star, we show that a small coronagraph can characterize the spectral properties of a 2-AU Jupiter up to 10 pc and the cloud and surface coverage of super-Earths in the habitable zone for a few stars within 4-5 pc. Potentially, SPICES could perform analysis of a hypothetical Earth-size planet around α Cen A and B. <P /> [less ▲]

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See detailSPICES: a 1.5-m space coronagraph for spectro-polarimetric characterization of cold exoplanets
Maire, Anne-Lise ULiege; Boccaletti, Anthony; Schneider, Jean et al

in Space Telescopes and Instrumentation 2012: Optical, Infrared, and Millimeter Wave (2012, September 01)

The study of the physico-chemical properties of wide-separated exoplanets (> 1 AU) is a major goal of high-contrast imaging techniques. SPICES (Spectro-Polarimetric Imaging and Characterization of ... [more ▼]

The study of the physico-chemical properties of wide-separated exoplanets (> 1 AU) is a major goal of high-contrast imaging techniques. SPICES (Spectro-Polarimetric Imaging and Characterization of Exoplanetary Systems) is a project of space coronagraph dedicated to the spectro-polarimetric analysis of gas and ice giant planets, super-Earths and circumstellar disks in visible light at a spectral resolution of about 40. After recalling the science cases of the mission, we describe the optical design and the critical subsystems of the instrument. We then discuss the SPICES performance that we derived from numerical simulations. <P /> [less ▲]

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See detailSPICES: Spectro-polarimetric imaging and characterization of exoplanetary systems
Boccaletti, Anthony; Maire, Anne-Lise ULiege; Galicher, Raphaël et al

Conference (2012)

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