2014/02/05 by Gaspard Duchêne, G. Duchene, P. Arriaga +27
Physics and Astronomy · #Asteroid belt #Astro and Planetary Science #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Brightness #Debris #Debris disk #Optics #Physics #Planet #Planetary system #Population #Radiative transfer #Solar System #Stellar, planetary, and galactic studies #astro-ph.SR
paper · pdf · doi:10.1088/0004-637x/784/2/148
50 pages, 12 figures, 5 tables, accepted for publication in the Astrophysical Journal
arxiv created 2014/02/05 · openalex publication_date 2014/03/18 · arxiv updated 2014/10/29 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
We present far-infrared and submillimeter images of the η Crv debris disk system obtained with Herschel and SCUBA-2, as well as Hubble Space Telescope visible and near-infrared coronagraphic images. In the 70 μm Herschel image, we clearly separate the thermal emission from the warm and cold belts in the system, find no evidence for a putative dust population located between them, and precisely determine the geometry of the outer belt. We also find marginal evidence for azimuthal asymmetries and a global offset of the outer debris ring relative to the central star. Finally, we place stringent upper limits on the scattered light surface brightness of the outer ring. Using radiative transfer modeling, we find that it is impossible to account for all observed properties of the system under the assumption that both rings contain dust populations with the same properties. While the outer belt is in reasonable agreement with the expectations of steady-state collisional cascade models, albeit with a minimum grain size that is four times larger than the blow-out size, the inner belt appears to contain copious amounts of small dust grains, possibly below the blow-out size. This suggests that the inner belt cannot result from a simple transport of grains from the outer belt and rather supports a more violent phenomenon as its origin. We also find that the emission from the inner belt has not declined over three decades, a much longer timescale than its dynamical timescale, which indicates that the belt is efficiently replenished.