Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Herschel SPIRE FTS telescope model correction   Emission from the Herschel telescope is the dominant source of radiation for
the majority of SPIRE Fourier transform spectrometer (FTS) observations,
despite the exceptionally low emissivity of the primary and secondary mirrors.
Accurate modelling and removal of the telescope contribution is, therefore, an
important and challenging aspect of FTS calibration and data reduction
pipeline. A dust-contaminated telescope model with time invariant mirror
emissivity was adopted before the Herschel launch. However, measured FTS
spectra show a clear evolution of the telescope contribution over the mission
and strong need for a correction to the standard telescope model in order to
reduce residual background (of up to 7 Jy) in the final data products.
Systematic changes in observations of dark sky, taken over the course of the
mission, provide a measure of the evolution between observed telescope emission
and the telescope model. These dark sky observations have been used to derive a
time dependent correction to the telescope emissivity that reduces the
systematic error in the continuum of the final FTS spectra to ~0.35 Jy.

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The categories of this paper are: eess
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The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
3
The categories of this paper are: physics
0
The categories of this paper are: hep-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: nucl-ex
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The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
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The categories of this paper are: adap-org
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The categories of this paper are: plasm-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: comp-gas
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The categories of this paper are: math
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The categories of this paper are: chao-dyn
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The categories of this paper are: supr-con