Is the HD 15115 inner disk really asymmetrical ?

Abstract

Context. Debris disks are intrinsically connected to the planetary system's formation and evolution. The development of high-contrast imaging techniques in the past 20 years is now allowing the detection of faint material around bright stars with high angular resolution, hence opening an avenue to study in detail the structures of circumstellar disks and their relation to planetary formation. Aims. The purpose of this paper is to revisit the morphology of the almost edge-on debris disk around HD 15115. Methods. We analyzed data from the Gemini science archive obtained in 2009 and 2011 with the Near-Infrared Coronagraphic Imager instrument in the H and Ks bands using coronagraphy and angular differential imaging tech- niques. Results. We resolved the disk in both the H and Ks bands. We confirmed the position angles inferred by previous authors, as well as the brightness asymmetry, which is the origin of the object's nickname, the blue needle. We were able to detect the bow-like shape of the disk suspected from other observations. However, these new NICI images suggest the presence of a highly inclined ring-like disk of which we see the brighter side and the ansae located at 90 AU symmetrically about the star. The inner part is likely depleted of dust. The fainter side of the disk is suspected but not firmly detected, which also indicates a large anisotropic scattering factor. Conclusions. The morphological symmetry of the disk contrasts with the obvious brightness asymmetry. This asymmetry may be explained by the coexistence of several types of grains in this disk and/or variable dust density. Interaction with the interstellar medium was invoked by previous authors as a possible explanation but other mechanisms may account for the brightness asymmetry, for instance a recent collision in the disk

10 pages, 10 figures. Submitted in A&A on June 26, 2014. Accepted in A&A on August 29, 2014

References in corpus (34)

• Validation of the new Hipparcos reduction
• Angular Differential Imaging: a Powerful High-Contrast Imaging Technique
• Images of a fourth planet orbiting HR 8799
• A giant planet imaged in the disk of the young star Beta Pictoris
• Detection and Characterization of Exoplanets and Disks using Projections on Karhunen-Loeve Eigenimages
• A probable giant planet imaged in the Beta Pictoris disk
• A new algorithm for point spread function subtraction in high-contrast imaging: a demonstration with angular differential imaging
• How Observations of Circumstellar Disk Asymmetries Can Reveal Hidden Planets: Pericenter Glow and its Application to the HR 4796 Disk
• Observations of gas flows inside a protoplanetary gap
• A planet on an inclined orbit as an explanation of the warp in the Beta Pictoris disk
• Molecular Gas Clumps from the Destruction of Icy Bodies in the $\beta$ Pictoris Debris Disk
• Impact of angular differential imaging on circumstellar disk images
• Debris Disks: Seeing Dust, Thinking of Planetesimals and Planets
• Imaging of a Transitional Disk Gap in Reflected Light: Indications of Planet Formation Around the Young Solar Analog LkCa 15
• Debris from giant impacts between planetary embryos at large orbital radii
• Confirmation of the planet around HD 95086 by direct imaging
• The Gemini NICI Planet-Finding Campaign : Discovery of a Substellar L Dwarf Companion to the Nearby Young M Dwarf CD-35 2722
• An icy Kuiper-Belt around the young solar-type star HD 181327
• HST/NICMOS2 coronagraphic observations of the circumstellar environment of three old PMS stars: HD 100546, SAO 206462 and MWC 480
• Discovery of extreme asymmetry in the debris disk surrounding HD 15115
• Structure and evolution of debris disks around F-type stars: I. Observations, database and basic evolutionary aspects
• beta Pic b position relative to the Debris Disk
• Confidence Level and Sensitivity Limits in High Contrast Imaging
• Images of the Extended Outer Regions of the Debris Ring Around HR 4796 A
• Imaging Discovery of the Debris Disk Around HIP 79977
• Multiple spiral patterns in the transitional disk of HD 100546
• Dissecting the Moth: Discovery of an off-centered ring in the HD 61005 debris disk with high-resolution imaging
• Does the Debris Disk around HD 32297 Contain Cometary Grains?
• The Gray Needle: Large Grains in the HD 15115 Debris Disk from LBT/PISCES/Ks and LBTI/LMIRcam/L' Adaptive Optics Imaging
• Morphology of the very inclined debris disk around HD 32297
• Color Gradients Detected in the HD 15115 Circumstellar Disk
• Very deep images of the innermost regions of the beta Pictoris debris disc at Lp
• Keck/NIRC2 Imaging of the Warped, Asymmetric Debris Disk around HD 32297
• Independent confirmation of β Pictoris b imaging with NICI

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