Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Surface States and Resonances in Field Emission from Low Index Facets of
  Clean Tungsten   The energies, widths, and shapes of features observed in the total energy
distributions in field emission from W(100) and W(111) are compared with the
results of a full-potential LAPW calculation of the surface density of states
based on a supercell model of the crystal structure at the metal-vacuum
interface. The Swanson hump on W(100) is attributed to two bands of surface
states and surface resonances of dz^2 symmetry that are highly localised at the
center of the surface Brillouin zone (Gamma_bar), and a second peak observed at
lower energy is attributed to a band of surface resonances, also of dz^2
symmetry, centred at 0.11 A^(-1) along Gamma_bar to X_bar. The energy scale of
the calculated total energy distribution is compressed by about 20% relative to
the experimental data. The present calculation yields strong evidence that the
broad asymmetric peak observed on W(111) is due to emission from a band of
surface resonances. Further calculations for W(111) are proposed both to test
the accuracy of the band model and to take into account the velocity factor
that enters in a calculation of the emission current.

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The categories of this paper are: econ
31
The categories of this paper are: ao-sci
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The categories of this paper are: q-bio
3
The categories of this paper are: physics
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The categories of this paper are: quant-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: nucl-ex
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The categories of this paper are: cmp-lg
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The categories of this paper are: plasm-ph
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The categories of this paper are: hep-th
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The categories of this paper are: acc-phys
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The categories of this paper are: bayes-an
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The categories of this paper are: gr-qc
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The categories of this paper are: eess
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The categories of this paper are: chao-dyn
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The categories of this paper are: q-alg