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A Three Dimensional View of Gomezs Hamburger

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 نشر من قبل Richard Teague
 تاريخ النشر 2020
  مجال البحث فيزياء
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Unraveling the 3D physical structure, the temperature and density distribution, of protoplanetary discs is an essential step if we are to confront simulations of embedded planets or dynamical instabilities. In this paper we focus on Submillimeter Array observations of the edge-on source, Gomezs Hamburger, believed to host an over-density hypothesised to be a product of gravitational instability in the disc, GoHam b. We demonstrate that, by leveraging the well characterised rotation of a Keplerian disc to deproject observations of molecular lines in position-position-velocity space into disc-centric coordinates, we are able to map out the emission distribution in the (r, z) plane and (x, y, z) space. We show that 12CO traces an elevated layer of $z,/,r sim 0.3$, while 13CO traces deeper in the disc at $z,/,r lesssim 0.2$. We localize emission associated with GoHam b, finding it at deprojected radius of approximately 500 au and at polar angle of +- 30 degrees from the disc major axis. At the spatial resolution of $sim 1.5^{primeprime}$, GoHam b is spatially unresolved, with an upper limit to its radius of $<190$~au.



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