Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Changes in the red giant and dusty environment of the recurrent nova RS
  Ophiuchi following the 2006 eruption   We present near infrared spectroscopy of the recurrent nova RS Oph obtained
on several occasions after its latest outburst in 2006 February. The 1-5 mircon
spectra are dominated by the red giant, but the H I, He I, and coronal lines
present during the eruption are present in all our observations. From the fits
of the computed infrared spectral energy distributions to the observed fluxes
we find T_eff=4200+/-200,K for the red giant. The first overtone CO bands at
2.3 micron, formed in the atmosphere of the red giant, are variable. The
spectra clearly exhibit an infrared excess due to dust emission longward of 5
micron; we estimate an effective temperature for the emitting dust shell of
500K, and find that the dust emission is also variable, being beyond the limit
of detection in 2007. Most likely, the secondary star in RS Oph is
intrinsically variable.

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The categories of this paper are: atom-ph
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The categories of this paper are: dg-ga
31
The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
35
The categories of this paper are: mtrl-th
18
The categories of this paper are: econ
2
The categories of this paper are: math
9
The categories of this paper are: nlin
13
The categories of this paper are: quant-ph
20
The categories of this paper are: acc-phys
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The categories of this paper are: q-fin
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The categories of this paper are: chao-dyn
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The categories of this paper are: plasm-ph
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The categories of this paper are: solv-int
27
The categories of this paper are: comp-gas