FIRST SCATTERED-LIGHT IMAGE OF THE DEBRIS DISK AROUND HD 131835 WITH THE GEMINI PLANET IMAGER

AbstractWe present first imaging results from the PALM-3000 adaptive optics system and PHARO camera on the Hale 5 m telescope. Observations using a vector vortex coronagraph have given us direct detections of the two-ring dusty debris system around the star HD 141569. Our observations reveal the inner clearing in the disk to unprecedentedly small angular separations, and are the most sensitive yet at the H and K bands. We are for the first time able to measure and compare the colors of the scattered light in the inner and outer dust rings, and find that the outer ring is significantly bluer than the inner ring.

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Quadrant polarization parameters for the scattered light of circumstellar disks. Analysis of debris disk models and observations of HR 4796A

Astronomy and Astrophysics ◽

10.1051/0004-6361/202140405 ◽

2021 ◽

Author(s):

H. M. Schmid

Keyword(s):

Scattered Light ◽

Circumstellar Disks ◽

Debris Disk

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Constraining the detectability of water ice in debris disks

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936014 ◽

2019 ◽

Vol 629 ◽

pp. A141

Author(s):

M. Kim ◽

S. Wolf ◽

A. Potapov ◽

H. Mutschke ◽

C. Jäger

Keyword(s):

Scattered Light ◽

Spectral Energy ◽

Debris Disks ◽

Water Ice ◽

Spatially Resolved ◽

Infrared Telescope ◽

Effective Medium Theories ◽

Debris Disk ◽

Highly Porous ◽

Entire Planet

Context. Water ice is important for the evolution and preservation of life. Identifying the distribution of water ice in debris disks is therefore of great interest in the field of astrobiology. Furthermore, icy dust grains are expected to play important roles throughout the entire planet formation process. However, currently available observations only allow deriving weak conclusions about the existence of water ice in debris disks. Aims. We investigate whether it is feasible to detect water ice in typical debris disk systems. We take the following ice destruction mechanisms into account: sublimation of ice, dust production through planetesimal collisions, and photosputtering by UV-bright central stars. We consider icy dust mixture particles with various shapes consisting of amorphous ice, crystalline ice, astrosilicate, and vacuum inclusions (i.e., porous ice grains). Methods. We calculated optical properties of inhomogeneous icy dust mixtures using effective medium theories, that is, Maxwell-Garnett rules. Subsequently, we generated synthetic debris disk observables, such as spectral energy distributions and spatially resolved thermal reemission and scattered light intensity and polarization maps with our code DMS. Results. We find that the prominent ~3 and 44 μm water ice features can be potentially detected in future observations of debris disks with the James Webb Space Telescope (JWST) and the Space Infrared telescope for Cosmology and Astrophysics (SPICA). We show that the sublimation of ice, collisions between planetesimals, and photosputtering caused by UV sources clearly affect the observational appearance of debris disk systems. In addition, highly porous ice (or ice-rich aggregates) tends to produce highly polarized radiation at around 3 μm. Finally, the location of the ice survival line is determined by various dust properties such as a fractional ratio of ice versus dust, physical states of ice (amorphous or crystalline), and the porosity of icy grains.

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A Resolved Millimeter Emission Belt in the AU Mic Debris Disk

Proceedings of the International Astronomical Union ◽

10.1017/s1743921313008752 ◽

2013 ◽

Vol 8 (S299) ◽

pp. 313-317

Author(s):

Meredith MacGregor

Keyword(s):

Angular Resolution ◽

Scattered Light ◽

Dust Emission ◽

Emission Peak ◽

Parametric Models ◽

Central Component ◽

Millimeter Wavelengths ◽

Stellar Photosphere ◽

Debris Disk ◽

Centroid Position

AbstractImaging debris disks at millimeter wavelengths is important, because emission at these long wavelengths is dominated by large grains with dynamics similar to the population of dust-producing planetesimals. We have used the SMA and ALMA to make 1.3 millimeter observations of the debris disk surrounding the nearby (9.9 pc), ~10 Myr-old, M-type flare star AU Microscopii. We characterize the disk by implementing Markov Chain Monte Carlo methods to fit parametric models to the visibilities. The millimeter observations reveal a belt of dust emission that peaks at a radius of 40 AU. This outer size scale agrees with predictions for a reservoir of planetesimals (a “birth ring”) based on the shape of the midplane scattered light profile. We do not find any significant asymmetries in the structure or the centroid position of the emission belt. The ALMA observations with a resolution of 0.6 arcsec (6 AU) also reveal a previously unknown central emission peak, ~6 times brighter than the stellar photosphere at these wavelengths. This central component remains unresolved and could be explained by stellar activity or an inner planetesimal belt located ≲3 AU from the star and containing roughly 1% the mass of the outer belt. Future observations with higher angular resolution will be able to distinguish between these possibilities.

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First Scattered-light Images of the Gas-rich Debris Disk around 49 Ceti

The Astrophysical Journal ◽

10.3847/2041-8213/834/2/l12 ◽

2017 ◽

Vol 834 (2) ◽

pp. L12 ◽

Cited By ~ 20

Author(s):

Élodie Choquet ◽

Julien Milli ◽

Zahed Wahhaj ◽

Rémi Soummer ◽

Aki Roberge ◽

...

Keyword(s):

Scattered Light ◽

Debris Disk

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Warm Debris Disks with WISE and HST

Proceedings of the International Astronomical Union ◽

10.1017/s1743921315006456 ◽

2015 ◽

Vol 10 (S314) ◽

pp. 175-178 ◽

Cited By ~ 1

Author(s):

Deborah Padgett ◽

Karl Stapelfeldt

Keyword(s):

Scattered Light ◽

Terrestrial Planets ◽

Wide Field ◽

Debris Disks ◽

Circumstellar Material ◽

Excess Emission ◽

Sky Survey ◽

Debris Disk ◽

Infrared Survey

AbstractUsing 22 μm data from the Wide Field Infrared Survey Explorer (WISE), we have completed a sensitive all-sky survey for debris disks in Hipparcos and Tycho catalog stars within 120 pc. This warm excess emission traces material in the circumstellar region likely to host terrestrial planets. Several hundred previously unknown debris disk candidates were identified. We are currently performing follow-up observations to characterize the stars, companions, and circumstellar material in these systems with a variety of facilities including Keck, Herschel, and HST. Thirteen WISE debris disks have been observed to date using HST/STIS coronagraphy. Five of these disks have been detected in scattered light. One is a large and highly asymmetric edge-on disk which appears to be both warped and bifurcated.

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HD141569A: Disk Dissipation Caught in Action

Proceedings of the International Astronomical Union ◽

10.1017/s1743921315006432 ◽

2015 ◽

Vol 10 (S314) ◽

pp. 201-202 ◽

Cited By ~ 2

Author(s):

J. Péricaud ◽

E. Di Folco ◽

A. Dutrey ◽

J.-C. Augereau ◽

V. Piétu ◽

...

Keyword(s):

Scattered Light ◽

Dust Emission ◽

Debris Disks ◽

Debris Disk ◽

Multiple Rings

AbstractDebris disks are usually thought to be gas-poor, the gas being dissipated by accretion or evaporation during the protoplanetary phase. HD141569A is a 5 Myr old star harboring a famous debris disk, with multiple rings and spiral features. I present here the first PdBI maps of the 12CO(2−1), 13CO(2−1) gas and dust emission at 1.3 mm in this disk. The analysis reveals there is still a large amount of (primordial) gas extending out to 250 AU, i.e. inside the rings observed in scattered light. HD141569A is thus a hybrid disk with a huge debris component, where dust has evolved and is produced by collisions, with a large remnant reservoir of gas.

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HD 117214 debris disk: scattered-light images and constraints on the presence of planets

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936828 ◽

2020 ◽

Vol 635 ◽

pp. A19 ◽

Cited By ~ 2

Author(s):

N. Engler ◽

C. Lazzoni ◽

R. Gratton ◽

J. Milli ◽

H. M. Schmid ◽

...

Keyword(s):

Imaging Techniques ◽

Scattered Light ◽

High Sensitivity ◽

3D Models ◽

Ring Structure ◽

Geometrical Parameters ◽

Debris Disks ◽

Disk Structure ◽

Ring Structures ◽

Debris Disk

Context. Young stars with debris disks are the most promising targets for an exoplanet search because debris indicate a successful formation of planetary bodies. Debris disks can be shaped by planets into ring structures that give valuable indications on the presence and location of planets in the disk. Aims. We performed observations of the Sco-Cen F star HD 117214 to search for planetary companions and to characterize the debris disk structure. Methods. HD 117214 was observed with the SPHERE subsystems IRDIS, IFS, and ZIMPOL at optical and near-IR wavelengths using angular and polarimetric differential imaging techniques. This provided the first images of scattered light from the debris disk with the highest spatial resolution of 25 mas and an inner working angle <0.1″. With the observations with IRDIS and IFS we derived detection limits for substellar companions. The geometrical parameters of the detected disk were constrained by fitting 3D models for the scattering of an optically thin dust disk. Investigating the possible origin of the disk gap, we introduced putative planets therein and modeled the planet–disk and planet–planet dynamical interactions. The obtained planetary architectures were compared with the detection limit curves. Results. The debris disk has an axisymmetric ring structure with a radius of 0.42(±0.01)″ or ~45 au and an inclination of 71(±2.5)° and exhibits a 0.4″ (~40 au) wide inner cavity. From the polarimetric data, we derive a polarized flux contrast for the disk of (Fpol)disk/F∗ = (3.1 ± 1.2) × 10−4 in the RI band. Conclusions. The fractional scattered polarized flux of the disk is eight times lower than the fractional IR flux excess. This ratio is similar to the one obtained for the debris disk HIP 79977, indicating that dust radiation properties are similar for these two disks. Inside the disk cavity we achieve high-sensitivity limits on planetary companions with a mass down to ~4 MJ at projected radial separations between 0.2″ and 0.4″. We can exclude stellar companions at a radial separation larger than 75 mas from the star.

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Two cold belts in the debris disk around the G-type star NZ Lupi

Astronomy and Astrophysics ◽

10.1051/0004-6361/201935135 ◽

2019 ◽

Vol 625 ◽

pp. A21 ◽

Cited By ~ 6

Author(s):

A. Boccaletti ◽

P. Thébault ◽

N. Pawellek ◽

A.-M. Lagrange ◽

R. Galicher ◽

...

Keyword(s):

Scattered Light ◽

Planetary Systems ◽

High Angular Resolution ◽

High Contrast ◽

Contrast Imaging ◽

Nearby Star ◽

Imaging Device ◽

High Contrast Imaging ◽

Debris Disk ◽

Dust Distribution

Context. Planetary systems hold the imprint of the formation and of the evolution of planets especially at young ages, and in particular at the stage when the gas has dissipated leaving mostly secondary dust grains. The dynamical perturbation of planets in the dust distribution can be revealed with high-contrast imaging in a variety of structures. Aims. SPHERE, the high-contrast imaging device installed at the VLT, was designed to search for young giant planets in long period, but is also able to resolve fine details of planetary systems at the scale of astronomical units in the scattered-light regime. As a young and nearby star, NZ Lup was observed in the course of the SPHERE survey. A debris disk had been formerly identified with HST/NICMOS. Methods. We observed this system in the near-infrared with the camera in narrow and broad band filters and with the integral field spectrograph. High contrasts are achieved by the mean of pupil tracking combined with angular differential imaging algorithms. Results. The high angular resolution provided by SPHERE allows us to reveal a new feature in the disk which is interpreted as a superimposition of two belts of planetesimals located at stellocentric distances of ~85 and ~115 au, and with a mutual inclination of about 5°. Despite the very high inclination of the disk with respect to the line of sight, we conclude that the presence of a gap, that is, a void in the dust distribution between the belts, is likely. Conclusions. We discuss the implication of the existence of two belts and their relative inclination with respect to the presence of planets.

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