References of "Absil, Olivier"
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See detailExozodiacal clouds: Hot and warm dust around main sequence stars
Kral, Quentin; Krivov, Alexander V.; Defrere, Denis ULiege et al

in Astronomical Review (in press)

A warm/hot dust component (at temperature $>$ 300K) has been detected around $\sim$ 20% of stars. This component is called "exozodiacal dust" as it presents similarities with the zodiacal dust detected in ... [more ▼]

A warm/hot dust component (at temperature $>$ 300K) has been detected around $\sim$ 20% of stars. This component is called "exozodiacal dust" as it presents similarities with the zodiacal dust detected in our Solar System, even though its physical properties and spatial distribution can be significantly different. Understanding the origin and evolution of this dust is of crucial importance, not only because its presence could hamper future detections of Earth-like planets in their habitable zones, but also because it can provide invaluable information about the inner regions of planetary systems. In this review, we present a detailed overview of the observational techniques used in the detection and characterisation of exozodiacal dust clouds ("exozodis") and the results they have yielded so far, in particular regarding the incidence rate of exozodis as a function of crucial parameters such as stellar type and age, or the presence of an outer cold debris disc. We also present the important constraints that have been obtained, on dust size distribution and spatial location, by using state-of-the-art radiation transfer models on some of these systems. Finally, we investigate the crucial issue of how to explain the presence of exozodiacal dust around so many stars (regardless of their ages) despite the fact that such dust so close to its host star should disappear rapidly due to the coupled effect of collisions and stellar radiation pressure. Several potential mechanisms have been proposed to solve this paradox and are reviewed in detail in this paper. The review finishes by presenting the future of this growing field. [less ▲]

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See detailCoronagraphy and Interferometry: Imaging the sky at high contrast and high-angular resolution
Defrere, Denis ULiege; Absil, Olivier ULiege

Scientific conference (2017, September 15)

Short overview of the main activities related to exoplanet imaging at the STAR Institute

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See detailDeep imaging search for planets forming in the TW Hya protoplanetary disk with the Keck/NIRC2 vortex coronagraph
Ruane, G.; Mawet, D.; Kastner, J. et al

in Astronomical Journal (The) (2017), 154

Distinct gap features in the nearest protoplanetary disk, TW Hya (distance of 59.5$\pm$0.9 pc), may be signposts of ongoing planet formation. We performed long-exposure thermal infrared coronagraphic ... [more ▼]

Distinct gap features in the nearest protoplanetary disk, TW Hya (distance of 59.5$\pm$0.9 pc), may be signposts of ongoing planet formation. We performed long-exposure thermal infrared coronagraphic imaging observations to search for accreting planets especially within dust gaps previously detected in scattered light and submm-wave thermal emission. Three nights of observations with the Keck/NIRC2 vortex coronagraph in $L^\prime$ (3.4-4.1$\mu$m) did not reveal any statistically significant point sources. We thereby set strict upper limits on the masses of non-accreting planets. In the four most prominent disk gaps at 24, 41, 47, and 88 au, we obtain upper mass limits of 1.6-2.3, 1.1-1.6, 1.1-1.5, and 1.0-1.2 Jupiter masses ($M_J$) assuming an age range of 7-10 Myr for TW Hya. These limits correspond to the contrast at 95\% completeness (true positive fraction of 0.95) with a 1\% chance of a false positive within $1^{\prime\prime}$ of the star. We also approximate an upper limit on the product of planet mass and planetary accretion rate of $M_p\dot{M}\lesssim10^{-8} M_J^2/yr$ implying that any putative $\sim0.1 M_J$ planet, which could be responsible for opening the 24 au gap, is presently accreting at rates insufficient to build up a Jupiter mass within TW Hya's pre-main sequence lifetime. [less ▲]

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See detailCharacterizing exoplanetary atmospheres with a mid-infrared nulling interferometer
Defrere, Denis ULiege; Léger, Alain; Absil, Olivier ULiege

Speech/Talk (2017)

The discovery of an increasing number of terrestrial planets around nearby stars marks the dawn of a new era in the exoplanet field: the characterization and understanding of their atmospheres. To make ... [more ▼]

The discovery of an increasing number of terrestrial planets around nearby stars marks the dawn of a new era in the exoplanet field: the characterization and understanding of their atmospheres. To make significant progress, it becomes clear that a large number of exoplanetary atmospheres have to be studied at various wavelengths. This is particularly relevant for identifying possible bio-signatures. In this talk, we present a concept of a space-based mid-infrared nulling spectrograph that can characterize a large number of exoplanetary atmospheres and provide key information on their size, surface temperature, and the presence of key molecules such as CO2, H2O, CH4 and O3. The proposed mission concept would be particularly suited to characterize Proxima Cen b. [less ▲]

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See detailLatest results with LBTI's Vortex coronagraph: real-time tip/tilt sensing, new data reduction algorithms, and YSO observations
Defrere, Denis ULiege; Hinz, Philip; Absil, Olivier ULiege

Speech/Talk (2017)

Vortex coronagraphs are among the most promising solutions to perform high contrast imaging at small angular separations from bright stars. They enhance the dynamic range at very small inner working angle ... [more ▼]

Vortex coronagraphs are among the most promising solutions to perform high contrast imaging at small angular separations from bright stars. They enhance the dynamic range at very small inner working angle (down to the diffraction limit of the telescope) and provide a clear 360 degree discovery space for high-contrast direct imaging of exoplanets. In 2013, we installed and commissioned an L-band coronagraph in LBTI/LMIRCam and obtained outstanding images of the four planets around HR8799 during the first hours on sky. In this presentation, we will present the results of the latest data reduction performed with the VIP software that is developed at the University of Liège and that features state-of-the-art image processing algorithms inherited from the field of background subtraction in computer vision (including machine learning algorithms and low rank modeling algorithms). We will also present the results obtained with the second L- and M-band coronagraph that was recently installed in LMIRCam to enable binocular Vortex observations. During the first observations (October 2016), we tested and validated a new real-time post-coronagraphic tip-tilt sensing technique (called QACITS) to quickly align each beam on the center of their respective Vortex coronagraph and obtained observations of a young star showing disk features near the resolution limit of each aperture. Finally, we will present some exciting prospects for the Vortex coronagraph that will be installed on VISIR and ELT/METIS. [less ▲]

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See detailResolved astrometric orbits of ten O-type binaries
Le Bouquin, J.-B.; Sana, H.; Gosset, Eric ULiege et al

in Astronomy and Astrophysics (2017), 601

Our long term aim is to derive model-independent stellar masses and distances for long period massive binaries by combining apparent astrometric orbit with double-lined radial velocity amplitudes (SB2 ... [more ▼]

Our long term aim is to derive model-independent stellar masses and distances for long period massive binaries by combining apparent astrometric orbit with double-lined radial velocity amplitudes (SB2). We follow-up ten O+O binaries with AMBER, PIONIER and GRAVITY at the VLTI. Here, we report about 130 astrometric observations over the last 7 years. We combine this dataset with distance estimates to compute the total mass of the systems. We also compute preliminary individual component masses for the five systems with available SB2 radial velocities. Nine over the ten binaries have their three dimensional orbit well constrained. Four of them are known colliding wind, non-thermal radio emitters, and thus constitute valuable targets for future high angular resolution radio imaging. Two binaries break the correlation between period and eccentricity tentatively observed in previous studies. It suggests either that massive star formation produce a wide range of systems, or that several binary formation mechanisms are at play. Finally, we found that the use of existing SB2 radial velocity amplitudes can lead to unrealistic masses and distances. If not understood, the biases in radial velocity amplitudes will represent an intrinsic limitation for estimating dynamical masses from SB2+interferometry or SB2+Gaia. Nevertheless, our results can be combined with future Gaia astrometry to measure the dynamical masses and distances of the individual components with an accuracy of 5 to 15\%, completely independently of the radial velocities. [less ▲]

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See detailOn-sky performance of the QACITS pointing control technique with the Keck/NIRC2 vortex coronagraph
Huby, Elsa ULiege; Bottom, Michael; Femenia, Bruno et al

in Astronomy and Astrophysics (2017), 600

A vortex coronagraph is now available for high contrast observations with the Keck/NIRC2 instrument at L band. Reaching the optimal performance of the coronagraph requires fine control of the wavefront ... [more ▼]

A vortex coronagraph is now available for high contrast observations with the Keck/NIRC2 instrument at L band. Reaching the optimal performance of the coronagraph requires fine control of the wavefront incident on the phase mask. In particular, centering errors can lead to significant stellar light leakage that degrades the contrast performance and prevents the observation of faint planetary companions around the observed stars. It is thus critical to correct for the possible slow drift of the star image from the phase mask center, generally due to mechanical flexures induced by temperature and/or gravity field variation, or to misalignment between the optics that rotate in pupil tracking mode. A control loop based on the QACITS algorithm for the vortex coronagraph has thus been developed and deployed for the Keck/NIRC2 instrument. This algorithm executes the entire observing sequence, including the calibration steps, initial centering of the star on the vortex center and stabilisation during the acquisition of science frames. On-sky data show that the QACITS control loop stabilizes the position of the star image down to 2.4 mas rms at a frequency of about 0.02 Hz. However, the accuracy of the estimator is probably limited by a systematic error due to a misalignment of the Lyot stop with respect to the entrance pupil, estimated to be on the order of 4.5 mas. A method to reduce the amplitude of this bias down to 1 mas is proposed. The QACITS control loop has been successfully implemented and provides a robust method to center and stabilize the star image on the vortex mask. In addition, QACITS ensures a repeatable pointing quality and significantly improves the observing efficiency compared to manual operations. It is now routinely used for vortex coronagraph observations at Keck/NIRC2, providing contrast and angular resolution capabilities suited for exoplanet and disk imaging. [less ▲]

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See detailCharacterizing exoplanetary atmospheres with a mid-infrared nulling spectrograph
Defrere, Denis ULiege; Léger, Alain; Absil, Olivier ULiege et al

Poster (2017, March 07)

The discovery of an increasing number of terrestrial planets around nearby stars marks the dawn of a new era in the exoplanet field: the characterization and understanding of their atmospheres. To make ... [more ▼]

The discovery of an increasing number of terrestrial planets around nearby stars marks the dawn of a new era in the exoplanet field: the characterization and understanding of their atmospheres. To make significant progress, it becomes clear that a large number of exoplanetary atmospheres have to be studied at various wavelengths. This is particularly relevant for identifying possible bio-signatures. In this poster, we present a concept of a space-based mid-infrared nulling spectrograph that can characterize a large number of exoplanetary atmospheres and provide key information on their size, surface temperature, and the presence of key molecules such as CO2, H2O, CH4 and O3. The proposed mission concept would be particularly suited to characterize Proxima Cen b. [less ▲]

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See detailStructure of Herbig AeBe disks at the milliarcsecond scale. A statistical survey in the H band using PIONIER-VLTI
Lazareff, B.; Berger, J.-P.; Kluska, J. et al

in Astronomy and Astrophysics (2017), 599

Context. It is now generally accepted that the near-infrared excess of Herbig AeBe stars originates in the dust of a circumstellar disk. Aims. The aims of this article are to infer the radial and vertical ... [more ▼]

Context. It is now generally accepted that the near-infrared excess of Herbig AeBe stars originates in the dust of a circumstellar disk. Aims. The aims of this article are to infer the radial and vertical structure of these disks at scales of order one au, and the properties of the dust grains. Methods. The program objects (51 in total) were observed with the H-band (1.6micron) PIONIER/VLTI interferometer. The largest baselines allowed us to resolve (at least partially) structures of a few tenths of an au at typical distances of a few hundred parsecs. Dedicated UBVRIJHK photometric measurements were also obtained. Spectral and 2D geometrical parameters are extracted via fits of a few simple models: ellipsoids and broadened rings with azimuthal modulation. Model bias is mitigated by parallel fits of physical disk models. Sample statistics were evaluated against similar statistics for the physical disk models to infer properties of the sample objects as a group. Results. We find that dust at the inner rim of the disk has a sublimation temperature Tsub~1800K. A ring morphology is confirmed for approximately half the resolved objects; these rings are wide delta_r>=0.5. A wide ring favors a rim that, on the star-facing side, looks more like a knife edge than a doughnut. The data are also compatible with a the combination of a narrow ring and an inner disk of unspecified nature inside the dust sublimation radius. The disk inner part has a thickness z/r~0.2, flaring to z/r~0.5 in the outer part. We confirm the known luminosity-radius relation; a simple physical model is consistent with both the mean luminosity-radius relation and the ring relative width; however, a significant spread around the mean relation is present. In some of the objects we find a halo component, fully resolved at the shortest interferometer spacing, that is related to the HAeBe class. [less ▲]

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See detailVLT/SPHERE robust astrometry of the HR8799 planets at milliarcsecond-level accuracy. Orbital architecture analysis with PyAstrOFit
Wertz, Olivier; Absil, Olivier ULiege; Gómez González, Carlos ULiege et al

in Astronomy and Astrophysics (2017), 598

HR8799 is orbited by at least four giant planets, making it a prime target for the recently commissioned Spectro-Polarimetric High-contrast Exoplanet REsearch (VLT/SPHERE). As such, it was observed on ... [more ▼]

HR8799 is orbited by at least four giant planets, making it a prime target for the recently commissioned Spectro-Polarimetric High-contrast Exoplanet REsearch (VLT/SPHERE). As such, it was observed on five consecutive nights during the SPHERE science verification in December 2014. We aim to take full advantage of the SPHERE capabilities to derive accurate astrometric measurements based on H-band images acquired with the Infra-Red Dual-band Imaging and Spectroscopy (IRDIS) subsystem, and to explore the ultimate astrometric performance of SPHERE in this observing mode. We also aim to present a detailed analysis of the orbital parameters for the four planets. We report the astrometric positions for epoch 2014.93 with an accuracy down to 2.0 mas, mainly limited by the astrometric calibration of IRDIS. For each planet, we derive the posterior probability density functions for the six Keplerian elements and identify sets of highly probable orbits. For planet d, there is clear evidence for nonzero eccentricity ($e \simeq 0.35$), without completely excluding solutions with smaller eccentricities. The three other planets are consistent with circular orbits, although their probability distributions spread beyond $e = 0.2$, and show a peak at $e \simeq 0.1$ for planet e. The four planets have consistent inclinations of about $30\deg$ with respect to the sky plane, but the confidence intervals for the longitude of ascending node are disjoint for planets b and c, and we find tentative evidence for non-coplanarity between planets b and c at the $2 \sigma$ level. [less ▲]

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See detailCharacterization of the low-mass companion HD 142527 B
Christiaens, Valentin ULiege; Casassus, Simon; Absil, Olivier ULiege et al

Poster (2017, February)

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See detailFirst scattered-light images of the gas-rich debris disk around 49 Ceti
Choquet, É.; Milli, J.; Wahhaj, Z. et al

in Astrophysical Journal Letters (2017), 834(2), 12

We present the first scattered-light images of the debris disk around 49 ceti, a ~40 Myr A1 main sequence star at 59 pc, famous for hosting two massive dust belts as well as large quantities of atomic and ... [more ▼]

We present the first scattered-light images of the debris disk around 49 ceti, a ~40 Myr A1 main sequence star at 59 pc, famous for hosting two massive dust belts as well as large quantities of atomic and molecular gas. The outer disk is revealed in reprocessed archival Hubble Space Telescope NICMOS F110W images, as well as new coronagraphic H band images from the Very Large Telescope SPHERE instrument. The disk extends from 1.1" (65 AU) to 4.6" (250 AU), and is seen at an inclination of 73degr, which refines previous measurements at lower angular resolution. We also report no companion detection larger than 3 M_Jup at projected separations beyond 20 AU from the star (0.34"). Comparison between the F110W and H-band images is consistent with a grey color of 49 ceti's dust, indicating grains larger than >2microns. Our photometric measurements indicate a scattering efficiency / infrared excess ratio of 0.2-0.4, relatively low compared to other characterized debris disks. We find that 49 ceti presents morphological and scattering properties very similar to the gas-rich HD 131835 system. From our constraint on the disk inclination we find that the atomic gas previously detected in absorption must extend to the inner disk, and that the latter must be depleted of CO gas. Building on previous studies, we propose a schematic view of the system describing the dust and gas structure around 49 ceti and hypothetic scenarios for the gas nature and origin. [less ▲]

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See detailThe W. M. Keck Observatory infrared vortex coronagraph and a first image of HIP79124 B
Serabyn, Eugene; Huby, Elsa ULiege; Matthews, Keith et al

in Astronomical Journal (The) (2017), 153(1), 43

An optical vortex coronagraph has been implemented within the NIRC2 camera on the Keck II telescope and used to carry out on-sky tests and observations. The development of this new L'-band observational ... [more ▼]

An optical vortex coronagraph has been implemented within the NIRC2 camera on the Keck II telescope and used to carry out on-sky tests and observations. The development of this new L'-band observational mode is described, and an initial demonstration of the new capability is presented: a resolved image of the low-mass companion to HIP79124, which had previously been detected by means of interferometry. With HIP79124 B at a projected separation of 186.5 mas, both the small inner working angle of the vortex coronagraph and the related imaging improvements were crucial in imaging this close companion directly. Due to higher Strehl ratios and more relaxed contrasts in L' band versus H band, this new coronagraphic capability will enable high-contrast small-angle observations of nearby young exoplanets and disks on a par with those of shorter-wavelength extreme adaptive optics coronagraphs. [less ▲]

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See detailCharacterization of the inner disk around HD 141569 A from Keck/NIRC2 L-band vortex coronagraphy
Mawet, Dimitri; Choquet, Élodie; Absil, Olivier ULiege et al

in Astronomical Journal (The) (2017), 153(1), 44

HD 141569 A is a pre-main sequence B9.5 Ve star surrounded by a prominent and complex circumstellar disk, likely still in a transition stage from protoplanetary to debris disk phase. Here, we present a ... [more ▼]

HD 141569 A is a pre-main sequence B9.5 Ve star surrounded by a prominent and complex circumstellar disk, likely still in a transition stage from protoplanetary to debris disk phase. Here, we present a new image of the third inner disk component of HD 141569 A made in the L' band (3.8 micron) during the commissioning of the vector vortex coronagraph recently installed in the near-infrared imager and spectrograph NIRC2 behind the W.M. Keck Observatory Keck II adaptive optics system. We used reference point spread function subtraction, which reveals the innermost disk component from the inner working distance of $\simeq 23$ AU and up to $\simeq 70$ AU. The spatial scale of our detection roughly corresponds to the optical and near-infrared scattered light, thermal Q, N and 8.6 micron PAH emission reported earlier. We also see an outward progression in dust location from the L'-band to the H-band (VLT/SPHERE image) to the visible (HST/STIS image), likely indicative of dust blowout. The warm disk component is nested deep inside the two outer belts imaged by HST NICMOS in 1999 (respectively at 406 and 245 AU). We fit our new L'-band image and spectral energy distribution of HD 141569 A with the radiative transfer code MCFOST. Our best-fit models favor pure olivine grains, and are consistent with the composition of the outer belts. While our image shows a putative very-faint point-like clump or source embedded in the inner disk, we did not detect any true companion within the gap between the inner disk and the first outer ring, at a sensitivity of a few Jupiter masses. [less ▲]

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See detailDiscovery of a low-mass companion inside the debris ring surrounding the F5V star HD 206893
Milli, J.; Hibon, P.; Christiaens, Valentin ULiege et al

in Astronomy and Astrophysics (2017), 597

<BR /> Aims: Uncovering the ingredients and the architecture of planetary systems is a very active field of research that has fuelled many new theories on giant planet formation, migration, composition ... [more ▼]

<BR /> Aims: Uncovering the ingredients and the architecture of planetary systems is a very active field of research that has fuelled many new theories on giant planet formation, migration, composition, and interaction with the circumstellar environment. We aim at discovering and studying new such systems, to further expand our knowledge of how low-mass companions form and evolve. <BR /> Methods: We obtained high-contrast H-band images of the circumstellar environment of the F5V star HD 206893, known to host a debris disc never detected in scattered light. These observations are part of the SPHERE High Angular Resolution Debris Disc Survey (SHARDDS) using the InfraRed Dual-band Imager and Spectrograph (IRDIS) installed on VLT/SPHERE. <BR /> Results: We report the detection of a source with a contrast of 3.6 × 10[SUP]-5[/SUP] in the H-band, orbiting at a projected separation of 270 milliarcsec or 10 au, corresponding to a mass in the range 24 to 73 M[SUB]Jup[/SUB] for an age of the system in the range 0.2 to 2 Gyr. The detection was confirmed ten months later with VLT/NaCo, ruling out a background object with no proper motion. A faint extended emission compatible with the disc scattered light signal is also observed. <BR /> Conclusions: The detection of a low-mass companion inside a massive debris disc makes this system an analog of other young planetary systems such as β Pictoris, HR 8799 or HD 95086 and requires now further characterisation of both components to understand their interactions. [less ▲]

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See detailPost-coronagraphic PSF sharpening with the vortex coronagraph
Orban De Xivry, Gilles ULiege; Jolivet, Aïssa ULiege; Huby, Elsa ULiege et al

Poster (2017)

Small-angle coronagraphs are key components for future instruments being developed for the ELTs. Because they deliver high contrast capabilities at small angular separations from the host star, they ... [more ▼]

Small-angle coronagraphs are key components for future instruments being developed for the ELTs. Because they deliver high contrast capabilities at small angular separations from the host star, they enable us to address by direct imaging one of the most important science case of the ELTs, the discovery and characterization of exoplanets and proto-planetary systems. Small-angle coronagraphs based on a focal-plane mask such as the vortex phase mask are however quite sensitive to low-order aberrations. They require precise wavefront control to avoid spurious starlight leakage that would decrease the contrast level and possibly mimic the signatures of off-axis companions. Here, we present a low-order wavefront sensor technique based on an iterative process using post-coronagraphic focal images with a vortex coronagraph. Our approach is similar to a PSF sharpening technique, which is sometimes used in classical imaging to reduce NCPA aberrations, but applied to post-coronagraphic images with the objective of minimizing the residual light of the on-axis source. We describe the laboratory implementation of this technique on the VODCA coronagraphic bench at the University of Liège, and present experimental results validating our method. Finally, we discuss its on-sky practicability and further possible developments. [less ▲]

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See detailHigh dynamic range thermal infrared imager for the VLTI
Defrere, Denis ULiege; Absil, Olivier ULiege; Ertel, Steve et al

in Pott, Jörg-Uwe; Surdej, Jean (Eds.) Future of otpical-infrared interferometry in Europe (2017)

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See detailProspects for the characterization of exozodiacal dust with the VLTI
Ertel, Steve; Absil, Olivier ULiege; Augereau, Jean-Charles et al

in Pott, Jörg-Uwe; Surdej, Jean (Eds.) Future of optical-infrared interferometry in Europe (2017)

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See detailVIP: Vortex Image Processing package for high-contrast direct imaging
Gómez González, Carlos ULiege; Wertz, Olivier; Absil, Olivier ULiege et al

in Astronomical Journal (The) (2017)

We present the Vortex Image Processing (VIP) library, a python package dedicated to astronomical high-contrast imaging. Our package relies on the extensive python stack of scientific libraries and aims to ... [more ▼]

We present the Vortex Image Processing (VIP) library, a python package dedicated to astronomical high-contrast imaging. Our package relies on the extensive python stack of scientific libraries and aims to provide a flexible framework for high-contrast data and image processing. In this paper, we describe the capabilities of VIP related to processing image sequences acquired using the angular di↵erential imaging (ADI) observing technique. VIP implements functionalities for building high-contrast data processing pipelines, encompass- ing pre- and post-processing algorithms, potential sources position and flux estimation, and sensitivity curves generation. Among the reference point-spread function subtraction techniques for ADI post-processing, VIP includes several flavors of principal component analysis (PCA) based algorithms, such as annular PCA and incremental PCA algorithm capable of processing big datacubes (of several gigabytes) on a computer with limited memory. Also, we present a novel ADI algorithm based on non-negative matrix factorization (NMF), which comes from the same family of low-rank matrix approximations as PCA and provides fairly similar results. We showcase the ADI capabilities of the VIP library using a deep sequence on HR8799 taken with the LBTI/LMIRCam and its recently commissioned L-band vortex coronagraph. Using VIP we investigated the presence of additional companions around HR8799 and did not find any significant additional point source beyond the four known planets. VIP is available at http://github.com/vortex-exoplanet/VIP and is accompanied with Jupyter notebook tutorials illustrating the main functionalities of the library. [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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