Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Broadband Observations of the Be/X-ray Binary Pulsar RX J0440.9+4431:
  Discovery of a Cyclotron Absorption Line   We report the results of an analysis of data obtained with the INTEGRAL,
Swift and RXTE observatories during the 2010 April and September outbursts of
the X-ray pulsar RX J0440.9+4431. The temporal and spectral properties of the
pulsar in a wide energy band (0.6-120 keV) were studied for the first time. We
discovered a ~32 keV cyclotron resonant scattering feature in the source
spectrum, that allowed us to estimate the magnetic field strength of the
neutron star as B~3.2 x 10^12 G. The estimate of the magnetic field strength
was confirmed by a comprehensive analysis of the noise power spectrum of the
source. Based on the recurrence time between Type I outbursts the orbital
period of the binary system can be estimated as ~155 days. We have shown that
the pulse profile has a sinusoidal-like single-peaked shape and has practically
no dependence on the source luminosity or energy band.

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The categories of this paper are: funct-an
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The categories of this paper are: cs
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The categories of this paper are: ao-sci
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The categories of this paper are: gr-qc
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The categories of this paper are: atom-ph
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The categories of this paper are: stat
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-th
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The categories of this paper are: q-fin
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The categories of this paper are: physics
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The categories of this paper are: econ
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The categories of this paper are: bayes-an
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The categories of this paper are: q-alg
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The categories of this paper are: chem-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: math-ph