Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Discovery of a millisecond pulsar in the 5.4 day binary 3FGL
  J1417.5-4402: observing the late phase of pulsar recycling   In a search of the unidentified Fermi gamma-ray source 3FGL J1417.5-4402 with
the Parkes radio telescope, we discovered PSR J1417-4402, a 2.66 ms pulsar
having the same 5.4 day orbital period as the optical and X-ray binary
identified by Strader et al. The existence of radio pulsations implies that the
neutron star is currently not accreting. Substantial outflows from the
companion render the radio pulsar undetectable for more than half of the orbit,
and may contribute to the observed Halpha emission. Our initial pulsar
observations, together with the optically inferred orbit and inclination, imply
a mass ratio of 0.171+/-0.002, a companion mass of M_2=0.33+/-0.03 Msun, and a
neutron star mass in the range 1.77<M_1<2.13 Msun. However, there remains a
discrepancy between the distance of 4.4 kpc inferred from the optical
properties of the companion and the smaller radio dispersion measure distance
of 1.6 kpc. The smaller distance would reduce the inferred Roche-lobe filling
factor, increase the inferred inclination angle, and decrease the masses. As a
wide binary, PSR J1417-4402 differs from the radio-eclipsing black widow and
redback pulsars being discovered in large numbers by Fermi. It is probably a
system that began mass transfer onto the neutron star after the companion star
left the main sequence. The companion should end its evolution as a He white
dwarf in a 6-20 day orbit, i.e., as a typical binary millisecond pulsar
companion.

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The categories of this paper are: q-fin
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The categories of this paper are: chem-ph
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The categories of this paper are: supr-con
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The categories of this paper are: math
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The categories of this paper are: plasm-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: bayes-an
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The categories of this paper are: chao-dyn
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The categories of this paper are: q-alg
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The categories of this paper are: solv-int
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The categories of this paper are: cond-mat
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The categories of this paper are: econ
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The categories of this paper are: dg-ga
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The categories of this paper are: nlin
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The categories of this paper are: q-bio
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The categories of this paper are: cmp-lg