Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Beam Emittance Measurements for the Low-Energy Demonstration Accelerator
  Radio-Frequency Quadrupole   The Low-Energy Demonstration Accelerator (LEDA) radio-frequency quadrupole
(RFQ) is a 100% duty factor (CW) linac that delivers >100 mA of H+ beam at 6.7
MeV. The 8-m-long, 350-MHz RFQ structure accelerates a dc, 75-keV, 110-mA H+
beam from the LEDA injector with >90% transmission. LEDA [1,2] consists of a
75-keV proton injector, 6.7-MeV, 350-MHz CW RFQ with associated high-power and
low-level rf systems, a short high-energy beam transport (HEBT) and high-power
(670-kW CW) beam stop. The beam emittance is inferred from wire scanner
measurements of the beam profile at a single location in the HEBT. The beam
profile is measured as a function of the magnetic field gradient in one of the
HEBT quadrupoles. As the gradient is changed the spot size passes through a
transverse waist. Measurements are presented for peak currents between 25 and
100 mA.

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The categories of this paper are: q-fin
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The categories of this paper are: nucl-th
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The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
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The categories of this paper are: hep-lat
28
The categories of this paper are: alg-geom
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The categories of this paper are: econ
37
The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: ao-sci
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The categories of this paper are: dg-ga
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The categories of this paper are: acc-phys
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The categories of this paper are: patt-sol
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The categories of this paper are: cond-mat
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The categories of this paper are: comp-gas