Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Imaging polarimetry and spectropolarimetry of comet C/2013 R1 (Lovejoy)   We have obtained imaging polarimetry of the comet C/2013 R1 (Lovejoy) with
2-Channel-Focal-Reducer Rozhen instrument at 2m Ritchey-Chr\'etien-Coud\'e
telescope of the Bulgarian National Astronomical Observatory Rozhen in two dust
continuum filters covering wavelength intervals clear from molecular emissions
and centred at $4430\AA$ in (blue filter) and at $6840\AA$ in (red filter). In
imaging mode we measured the degree of linear polarisation $17.01\pm0.09$% in
the blue and $18.81\pm0.02$% in the red, which is in a very good agreement with
measurements of other comets at the similar phase angle. We have also obtained
polarisation maps in both filters. We found a strong correlation between the
spatial distribution of the polarisation and the dust colour.
Spectropolarimetry of the nucleus region shows an increase of the polarisation
with wavelength, and a depolarisation in the spectral regions with gas emission
lines, most noticeable in C$_2$ emission band, which shows a polarisation of
$6.0\pm1.1$%.

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The categories of this paper are: bayes-an
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The categories of this paper are: chem-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: ao-sci
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The categories of this paper are: hep-ex
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The categories of this paper are: hep-th
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The categories of this paper are: cond-mat
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The categories of this paper are: solv-int
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The categories of this paper are: math
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The categories of this paper are: comp-gas
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The categories of this paper are: quant-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: nlin
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The categories of this paper are: chao-dyn
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The categories of this paper are: eess
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The categories of this paper are: plasm-ph