Preliminary model of the outer disk of RU Lup presently showing only four dark gaps

Dimitris M. Christodoulou; Demosthenes Kazanas

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arXiv · 1902.01222

Preliminary model of the outer disk of RU Lup presently showing only four dark gaps

Dimitris M. Christodoulou·Demosthenes Kazanas

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Abstract

Recent ALMA/DSHARP observations reveal that the disk of RU Lup shows presently only four dark gaps at large radii in which planets are presumably already orbiting. This gap arrangement is quite similar to the current structure of the outer planets in our solar system. Although there may be more undetected planets forming in the inner disk of RU Lup, the information obtained from the current observations prompted us to fit preliminary models with an isothermal oscillatory density profile to the outer disk of RU Lup. The best-fit model confirms that several physical properties of the disk of RU Lup are comparable to those of our solar nebula to within factors of 1.0-2.3; but there are some differences as well: central density ($\rho_0$), centrifugal support ($\beta_0$), and core angular velocity ($\Omega_0$) in RU Lup are smaller by factors of 5.5, 8.0, and 18, respectively, whereas the inner core radius ($R_1$) of RU Lup is 25 times larger. The smaller values found for RU Lup are linked to the (apparently gap-empty) inner 10 AU of its disk, a region that is presently inadequately resolved.

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Dimitris M. Christodoulou, Demosthenes Kazanas. 2019-02-01. Preliminary model of the outer disk of RU Lup presently showing only four dark gaps. https://arxiv.org/abs/1902.01222

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