Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Near-Infrared Imaging of a Spiral in the CQ Tau Disk   We present $L^\prime$-band Keck/NIRC2 imaging and $H$-band
Subaru/AO188+HiCIAO polarimetric observations of CQ Tau disk with a new spiral
arm. Apart from the spiral feature our observations could not detect any
companion candidates. We traced the spiral feature from the $r^2$-scaled HiCIAO
polarimetric intensity image and the fitted result is used for forward modeling
to reproduce the ADI-reduced NIRC2 image. We estimated the original surface
brightness after throughput correction in $L^\prime$-band to be $\sim126$
mJy/arcsec$^2$ at most. We suggest that the grain temperature of the spiral may
be heated up to $\sim$200 K in order to explain both of the $H$- and
$L^{\prime}$-bands results. The $H$-band emission at the location of the spiral
originates from the scattering from the disk surface while both scattering and
thermal emission may contribute to the $L^{\prime}$-band emission. If the
central star is only the light source of scattered light, the spiral emission
at $L^\prime$-band should be thermal emission. If an inner disk also acts as
the light source, the scattered light and the thermal emission may equally
contribute to the $L^\prime$-band spiral structure.

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The categories of this paper are: cs
23
The categories of this paper are: solv-int
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The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
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The categories of this paper are: cond-mat
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
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The categories of this paper are: math-ph
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The categories of this paper are: nlin
33
The categories of this paper are: plasm-ph
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The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
13
The categories of this paper are: quant-ph