Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Lifetime of quasi-particles in the nearly-free electron metal Sodium   We report a high-resolution angle-resolved photoemission (ARPES) study of the
prototypical nearly-free electron metal Sodium. The observed mass enhancement
is in qualitative agreement with previous studies [PRL 55, 1912 (1985)]. The
new results on the lifetime broadening demand theories which go beyond the
random phase approximation. On the other hand, our results do not support the
discussed strong coupling of the conduction electrons to spin fluctuations.
Moreover, a comparison with earlier electron energy-loss data on Sodium [PRB
40, 10181 (1989)] yields a strong reduction of the mass enhancement of dipolar
electron-hole excitations compared to that of monopole hole excitations,
measured by ARPES. Finally, our results on the lifetime of hot electrons in Na,
70 eV above the Fermi level differ strongly from existing theoretical
calculations and experiments on the mean-free path of hot electrons in simple
metals.

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The categories of this paper are: q-fin
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The categories of this paper are: supr-con
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The categories of this paper are: eess
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The categories of this paper are: nucl-ex
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The categories of this paper are: atom-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: hep-th
3
The categories of this paper are: physics
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The categories of this paper are: nlin
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The categories of this paper are: plasm-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: dg-ga
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The categories of this paper are: q-alg
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: acc-phys