Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A large spin-up rate measured with INTEGRAL in the High Mass X-ray
  Binary Pulsar SAXJ2103.5+4545   The High Mass X-ray Binary Pulsar SAXJ2103.5+4545 has been observed with
INTEGRAL several times during the last outburst in 2002-2004. We report a
comprehensive study of all INTEGRAL observations, allowing a study of the pulse
period evolution during the recent outburst. We measured a very rapid spin-up
episode, lasting 130days, which decreased the pulse period by 1.8s. The spin-up
rate, pdot=-1.5e-7 s/s, is the largest ever measured for SAXJ2103.5+4545, and
it is among the fastest for an accreting pulsar. The pulse profile shows
evidence for temporal variability, apparently not related to the source flux or
to the orbital phase. The X-ray spectrum is hard and there is significant
emission up to 150keV. A new derivation of the orbital period, based on RXTE
data, is also reported.

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The categories of this paper are: nucl-th
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The categories of this paper are: math-ph
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The categories of this paper are: stat
31
The categories of this paper are: ao-sci
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The categories of this paper are: q-bio
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The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: funct-an
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The categories of this paper are: acc-phys
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-th
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The categories of this paper are: comp-gas
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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: math