Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Discovery of gamma and X-ray pulsations from the young and energetic PSR
  J1357-6429 with Fermi and XMM-Newton   Since the launch of the Fermi satellite, the number of known gamma-ray
pulsars has increased tenfold. Most gamma-ray detected pulsars are young and
energetic, and many are associated with TeV sources. PSR J1357-6429 is a high
spin-down power pulsar (Edot = 3.1 * 10^36 erg/s), discovered during the Parkes
multibeam survey of the Galactic plane, with significant timing noise typical
of very young pulsars. In the very-high-energy domain, H.E.S.S. has reported
the detection of the extended source HESS J1356-645 (intrinsic Gaussian width
of 12') whose centroid lies 7' from PSR J1357-6429. Using a rotational
ephemeris obtained with 74 observations made with the Parkes telescope at 1.4
GHz, we phase-fold more than two years of gamma-ray data acquired by Fermi-LAT
as well as those collected with XMM-Newton, and perform gamma-ray spectral
modeling. Significant gamma and X-ray pulsations are detected from PSR
J1357-6429. The light curve in both bands shows one broad peak. Gamma-ray
spectral analysis of the pulsed emission suggests that it is well described by
a simple power-law of index 1.5 +/- 0.3stat +/- 0.3syst with an exponential
cut-off at 0.8 +/- 0.3stat +/- 0.3syst GeV and an integral photon flux above
100 MeV of (6.5 +/- 1.6stat +/- 2.3syst) * 10^-8 cm^-2 s^-1. The X-ray spectra
obtained from the new data provide results consistent with those reported by
Zavlin (2007). Upper limits on the gamma-ray emission from its potential pulsar
wind nebula (PWN) are also reported. Assuming a distance of 2.4 kpc, the Fermi
LAT energy flux yields a gamma-ray luminosity for PSR J1357-6429 of L_gamma =
(2.13 +/- 0.25stat +/- 0.83syst) * 10^34 erg/s, consistent with an L_gamma
\propto sqrt(Edot) relationship. The Fermi non-detection of the pulsar wind
nebula associated with HESS J1356-645 provides new constraints on the electron
population responsible for the extended TeV emission.

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The categories of this paper are: supr-con
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The categories of this paper are: cond-mat
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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: econ
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The categories of this paper are: quant-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: chem-ph
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The categories of this paper are: physics
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The categories of this paper are: q-alg
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The categories of this paper are: chao-dyn
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The categories of this paper are: stat
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The categories of this paper are: eess
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The categories of this paper are: solv-int
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The categories of this paper are: hep-ex
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The categories of this paper are: bayes-an