Issue |
A&A
Volume 626, June 2019
|
|
---|---|---|
Article Number | A95 | |
Number of page(s) | 11 | |
Section | Planets and planetary systems | |
DOI | https://doi.org/10.1051/0004-6361/201834687 | |
Published online | 19 June 2019 |
First resolved observations of a highly asymmetric debris disc around HD 160305 with VLT/SPHERE★,★★
1
LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université Paris Diderot, Sorbonne Paris Cité,
5 place Jules Janssen,
92195
Meudon,
France
e-mail: clement.perrot@obspm.fr
2
Instituto de Física y Astronomía, Facultad de Ciencias, Universidad de Valparaíso,
Av. Gran Bretaña 1111,
Valparaíso,
Chile
3
Núcleo Milenio Formación Planetaria – NPF, Universidad de Valparaíso,
Av. Gran Bretaña 1111,
Valparaíso, Chile
4
CNRS, IPAG, Université Grenoble Alpes,
38000
Grenoble, France
5
CNRS, CNES, LAM, Aix-Marseille University,
Marseille,
France
6
INAF – Osservatorio Astronomico di Padova,
Vicolo dell Osservatorio 5,
35122
Padova,
Italy
7
INAF – Osservatorio Astrofisico di Catania,
Via S.Sofia 78,
95123
Catania,
Italy
8
Max Planck Institute for Astronomy,
Königstuhl 17,
69117
Heidelberg,
Germany
9
Institute for Astronomy, University of Edinburgh,
EH9 3HJ,
Edinburgh,
UK
10
Institute for Particle Physics and Astrophysics, ETH Zurich,
Wolfgang-Pauli-Strasse 27,
8093
Zurich,
Switzerland
11
Unidad Mixta Internacional Franco-Chilena de Astronomía, CNRS/INSU UMI 3386 and Departamento de Astronomía, Universidad de Chile,
Casilla 36-D,
Santiago, Chile
12
Geneva Observatory, University of Geneva,
Chemin des Mailettes 51,
1290
Versoix, Switzerland
13
Université Côte d’Azur, OCA, CNRS,
Lagrange,
France
14
CRAL, CNRS, Université Lyon 1, ENS,
9 avenue Charles André,
69561
Saint Genis Laval,
France
15
STAR Institute, University of Liège,
Allée du Six Août 19c,
4000
Liège,
Belgium
16
INCT, Universidad De Atacama,
calle Copayapu 485,
Copiapò,
Atacama,
Chile
17
DOTA, ONERA, Université Paris Saclay,
91123
Palaiseau, France
Received:
19
November
2018
Accepted:
15
April
2019
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.
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.
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.
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.
Key words: scattering / stars: individual: HD160305 / methods: observational / techniques: high angular resolution / planet-disk interactions / techniques: image processing
The reduced images (FITS files) are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/626/A95
© P. Clément et al. 2019
Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.