Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Deep Chandra X-ray Observatory Study of the Millisecond Pulsar
  Population in the Globular Cluster Terzan 5   We present an analysis of 745.6 ks of archival Chandra X-ray Observatory
Advanced CCD Imaging Spectrometer data accumulated between 2000 and 2016 of the
millisecond pulsar (MSP) population in the rich Galactic globular cluster
Terzan 5. Eight of the 37 MSPs with precise positions are found to have
plausible X-ray source matches. Despite the deep exposure, the remaining MSPs
are either marginally detected or have no obvious X-ray counterparts, which can
be attributed to the typically soft thermal spectra of rotation-powered MSPs,
which are strongly attenuated by the high intervening absorbing column
(~$10^{22}$ cm$^{-2}$) towards the cluster, and in some instances severe source
crowding/blending. For the "redback" MSP binaries, PSRs J1748-2446P and
J1748-2446ad, and the "black widow" binary PSRs J1748-2446O, we find clear
evidence for large-amplitude X-ray variability at the orbital period consistent
with an intrabinary shock origin. The third redback MSP in the cluster, PSR
J1748-2446A, shows large amplitude variations in flux on time scales of years,
possibility due to state transitions or intense flaring episodes from the
secondary star.

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The categories of this paper are: eess
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The categories of this paper are: adap-org
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The categories of this paper are: quant-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: hep-th
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The categories of this paper are: hep-ph
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The categories of this paper are: nlin
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The categories of this paper are: hep-lat
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The categories of this paper are: patt-sol
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The categories of this paper are: nucl-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: ao-sci
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The categories of this paper are: nucl-ex
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The categories of this paper are: cond-mat
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The categories of this paper are: gr-qc