Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The $\textit{Chandra}$ 3CR extragalactic survey at high redshift   We present the analysis of nine radio sources belonging to the Third
Cambridge Revised catalog (3CR) observed with $Chandra$ during Cycle 20 in the
redshift range between 1.5 and 2.5. This study completes the 3CR $Chandra$
Snapshot Survey thus guaranteeing the X-ray coverage of all 3CR sources
identified to date. This sample lists two compact steep spectrum sources, four
radio galaxies and three quasars. We detected X-ray emission from all nuclei,
with the only exception of 3C 326.1 and 3C 454.1 and from radio lobes in 6 out
of 9 sources at level of confidence larger than $\sim$5$\sigma$. We measured
X-ray fluxes and luminosities for all nuclei and lobes in the soft (0.5 - 1
keV), medium (1 - 2 keV) and hard (2 - 7 keV) X-ray bands. Since the discovered
X-ray extended emission is spatially coincident with the radio structure in all
cases, its origin could be due to Inverse Compton scattering of the Cosmic
Microwave Background (IC/CMB) occurring in radio lobes.

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The categories of this paper are: q-fin
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The categories of this paper are: plasm-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-ph
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The categories of this paper are: stat
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The categories of this paper are: q-bio
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The categories of this paper are: acc-phys
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The categories of this paper are: supr-con
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The categories of this paper are: quant-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: adap-org
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The categories of this paper are: chem-ph
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The categories of this paper are: cs
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The categories of this paper are: comp-gas
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The categories of this paper are: math-ph
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The categories of this paper are: ao-sci