Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The SPOT-IL Positron Beam Construction and Its Use for Doppler
  Broadening Measurement of Titanium Thin Films   The construction and first operation of the slow positron beam built at the
Hebrew University is reported here. The beam follows a traditional design,
using a 22Na source, a Tungsten moderator, and a target cell equipped with a
load-lock system for easy sample insertion. The beam energy varies between 0.03
keV and 30 keV. The detection system consists of two high purity Germanium
detectors, facing each other, allowing low-background Doppler-Broadening (DB)
measurements. Event readout is done using a state-of-the-art compact desktop
system. The target cell is designed to allow a combined measurement of DB and
sample conductivity, with the flexibility to add more detection options in the
future. The beam has been successfully tested by using it to charecterize
Titanium (Ti) films. Two 1.2 {\mu}m Ti films -- as produced, and after
annealing, were measured at various energies (2 keV - 25 keV), and the results
show consistent behavior with previous measurements.

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The categories of this paper are: hep-ex
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-th
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The categories of this paper are: math-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: patt-sol
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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: atom-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: hep-lat
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The categories of this paper are: eess
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The categories of this paper are: econ
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The categories of this paper are: chao-dyn
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The categories of this paper are: ao-sci
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The categories of this paper are: quant-ph