Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: High resolution observations of the outer disk around T Cha: the view
  from ALMA   T Cha is a young star surrounded by a transitional disk with signatures of
planet formation. We have obtained high-resolution and high-sensitivity ALMA
observations of T Cha in the ${\rm CO}(3$--$2)$, ${\rm ^{13}CO}(3$--$2)$, and
${\rm CS}(7$--$6)$ emission lines to reveal the spatial distribution of the
gaseous disk around the star. In order to study the dust within the disk we
have also obtained continuum images at 850$\mu$m from the line-free channels.
We have spatially resolved the outer disk around T Cha. Using the CO(3-2)
emission we derive a radius of $\sim$230 AU. We also report the detection of
the $^{13}$CO(3-2) and the CS(7-8) molecular emissions, which show smaller
radii than the CO(3-2) detection. The continuum observations at 850$\mu$m allow
the spatial resolution of the dusty disk, which shows two emission bumps
separated by $\sim$40AU, consistent with the presence of a dust gap in the
inner regions of the disk, and an outer radius of $\sim$80AU. Therefore, T Cha
is surrounded by a compact dusty disk and a larger and more diffuse gaseous
disk, as previously observed in other young stars. The continuum intensity
profiles are different at both sides of the disk suggesting possible dust
asymmetries. We derive an inclination of i(deg)=67$\pm$5, and a position angle
of PA (deg)= 113$\pm$6, for both the gas and dust disks. The comparison of the
ALMA data with radiative transfer models shows that the gas and dust components
can only be simultaneously reproduced when we include a tapered edge
prescription for the surface density profile. The best model suggests that most
of the disk mass is placed within a radius of $R<$ 50AU. Finally, we derive a
dynamical mass for the central object of $M_{*}$=1.5$\pm$0.2M$_{\odot}$,
comparable to the one estimated with evolutionary models for an age of
$\sim$10Myr.

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The categories of this paper are: cs
28
The categories of this paper are: alg-geom
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The categories of this paper are: hep-ex
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The categories of this paper are: math
27
The categories of this paper are: comp-gas
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The categories of this paper are: econ
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The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
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The categories of this paper are: cond-mat
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The categories of this paper are: hep-lat
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The categories of this paper are: q-bio
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The categories of this paper are: atom-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: stat
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The categories of this paper are: chao-dyn
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The categories of this paper are: q-alg