Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Dwarf Protoplanetary Disk around XZ Tau B   We report the discovery of a dwarf protoplanetary disk around the star XZ Tau
B that shows all the features of a classical transitional disk but on a much
smaller scale. The disk has been imaged with the Atacama Large
Millimeter/Submillimeter Array (ALMA), revealing that its dust emission has a
quite small radius of ~ 3.4 au and presents a central cavity of ~ 1.3 au in
radius that we attribute to clearing by a compact system of orbiting
(proto)planets. Given the very small radii involved, evolution is expected to
be much faster in this disk (observable changes in a few months) than in
classical disks (observable changes requiring decades) and easy to monitor with
observations in the near future. From our modeling we estimate that the mass of
the disk is large enough to form a compact planetary system.

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The categories of this paper are: cond-mat
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
28
The categories of this paper are: alg-geom
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
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The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
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The categories of this paper are: physics
26
The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th