Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Valence-Band UPS, 6$p$ Core-Level XPS Photoemission Spectroscopy, and
  Low-Energy Electron Diffraction of a Uranium (001) Single Crystal   Valence-band ultraviolet photoemission spectroscopy (UPS) at 173K and 6p
core-level X-ray photoemission spectroscopy (XPS) at room temperature were
performed on a high quality uranium single crystal. Significant agreement is
found with first-principles electronic band-structure calculations, using a
generalized gradient approximation (GGA). In addition, using Low Energy
Electron Diffraction (LEED) for the (001) surface, we find a well-ordered
orthorhombic crystallographic structure representative of the bulk material.

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The categories of this paper are: chem-ph
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The categories of this paper are: funct-an
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The categories of this paper are: alg-geom
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The categories of this paper are: stat
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The categories of this paper are: dg-ga
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The categories of this paper are: q-fin
1
The categories of this paper are: cs
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The categories of this paper are: atom-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: supr-con
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The categories of this paper are: chao-dyn
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The categories of this paper are: plasm-ph
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The categories of this paper are: physics
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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: econ