Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: High-contrast imaging of HD 163296 with the Keck/NIRC2 L'-band vortex
  coronograph   We present observations of the nearby (D$\sim$100\,pc) Herbig star HD~163296
taken with the vortex coronograph at Keck/NIRC2 in the L' band (3.7~$\mu$m), to
search for planetary mass companions in the ringed disc surrounding this
pre-main sequence star. The images reveal an arc-like region of scattered light
from the disc surface layers that is likely associated with the first bright
ring detected with ALMA in the $\lambda$=1.3mm dust continuum at $\sim$65~au.
We also detect a point-like source at $\sim$0\farcs5 projected separation in
the North-East direction, close to the inner edge of the second gap in the
millimetre images. Comparing the point source photometry with the atmospheric
emission models of non-accreting giant planets, we obtain a mass of 6--7~M$_J$
for a putative protoplanet, assuming a system age of 5~Myr. Based on the
contrast at a 95\% level of completeness calculated on the emission-free
regions of our images, we set upper limits for the masses of giant planets of
8--15~M$_J$, 4.5--6.5~M$_J$ and 2.5-4.0~M$_J$ at the locations of the first,
second and third gap in the millimetre dust continuum, respectively. Further
deep, high resolution thermal IR imaging of the HD~163296 system are warranted,
to confirm the presence and nature of the point source and to better understand
the structure of the dust disc.

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The categories of this paper are: cs
16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg
28
The categories of this paper are: alg-geom
18
The categories of this paper are: econ
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
26
The categories of this paper are: bayes-an
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
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The categories of this paper are: physics
9
The categories of this paper are: nlin
15
The categories of this paper are: nucl-ex
24
The categories of this paper are: dg-ga