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Constraining the Movement of the Spiral Features and the Locations of Planetary Bodies within the AB Aur System

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 نشر من قبل Jamie Lomax
 تاريخ النشر 2016
  مجال البحث فيزياء
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We present new analysis of multi-epoch, H-band, scattered light images of the AB Aur system. We used a Monte Carlo, radiative transfer code to simultaneously model the systems SED and H-band polarized intensity imagery. We find that a disk-dominated model, as opposed to one that is envelope dominated, can plausibly reproduce AB Aurs SED and near-IR imagery. This is consistent with previous modeling attempts presented in the literature and supports the idea that at least a subset of AB Aurs spirals originate within the disk. In light of this, we also analyzed the movement of spiral structures in multi-epoch H-band total light and polarized intensity imagery of the disk. We detect no significant rotation or change in spatial location of the spiral structures in these data, which span a 5.8 year baseline. If such structures are caused by disk-planet interactions, the lack of observed rotation constrains the location of the orbit of planetary perturbers to be >47 AU.

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