[en] In this paper, we present the results of three different studies of the Fomalhaut debris disk with infrared interferometry. First, VLTI/AMBER measurements are used to determine the position angle of the slightly oblate rapidly rotating photosphere by means of differential phase measurements across the Br-gamma photospheric line. This measurement allows us to confirm that the debris disk is located in the equatorial plane of its host star. Second, we use VLTI/VINCI to search for resolved near-infrared emission around the stellar photosphere, which would correspond to the presence of large amounts of hot dust grains located between the sublimation radius and the habitable zone. Our observations reveal a small excess of 0.88%+/-0.12% in K band relative to the photospheric flux. Finally, we use the Keck Interferometer Nuller in order to derive additional constraints on the nature of the resolved infrared emission. Our observations suggest a marginal detection of a circumstellar excess at 10 μm, which we use together with the VINCI detection to model the circumstellar emission. Preliminary results from this modeling effort are discussed.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Absil, Olivier ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astroph. extragalactique et observations spatiales (AEOS)
Mennesson, B.; Jet Propulsion Lab. (USA)
Le Bouquin, J.-B.; LAOG, CNRS, Univ. Joseph Fourier (France)
Augereau, J.-C.; LAOG, CNRS, Univ. Joseph Fourier (France)
Millan-Gabet, R.; Jet Propulsion Lab, (USA)
Colavita, M.; Jet Propulsion Lab, (USA)
Hinz, P.; Steward Observatory, The Univ. of Arizona (USA)
Liu, W.; Steward Observatory, The Univ. of Arizona (USA)
Serabyn, G.; Jet Propulsion Lab. (USA)
Language :
English
Title :
The Fomalhaut debris disk seen from every angle with interferometry
Publication date :
July 2010
Event name :
Astronomical Telescopes and Instrumentation 2010: Optical and Infrared Interferometry II
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