Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Preliminary RF design of an X-band linac for the EuPRAXIA@SPARC_LAB
  project   In the framework of the upgrade of the SPARC_LAB facility at INFN-LNF, named
EuPRAXIA@SPARC_LAB, a high gradient linac is foreseen. One of the most suitable
options is to realize it in X-band. A preliminary design study of both
accelerating structures and power distribution system has been performed. It is
based on 0.5 m long travelling wave (TW) accelerating structures operating in
the 2{\pi}/3 mode and fed by klystrons and pulse compressor systems. The main
parameters of the structures and linac are presented with the basic RF linac
layout.

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The categories of this paper are: adap-org
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The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg
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The categories of this paper are: acc-phys
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The categories of this paper are: mtrl-th
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The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: astro-ph
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The categories of this paper are: stat
4
The categories of this paper are: cond-mat
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The categories of this paper are: eess
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The categories of this paper are: hep-lat
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The categories of this paper are: q-fin
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The categories of this paper are: atom-ph
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The categories of this paper are: supr-con