Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Analytic Elastic Cross Sections for Electron-Atom Scattering from
  Generalized Fano Profiles of Overlapping Low-Energy Shape Resonances   The variation with energy of the total cross section for elastic electron
scattering from atoms of several elements is caused primarily by shape
resonances corresponding to the formation of temporary negative ions. It is
shown that such cross sections are expressible analytically in terms of a
constant background added to a "generalized Fano profile" [Durand Ph, et al
(2001) J. Phys. B: At. Mol. Opt. Phys. 34, 1953, ibid (2002) 35, 469]. In three
cases (sodium, magnesium and mercury), a detailed consideration proves that
this representation is accurate in a fairly wide energy range. Moreover, the
related momentum transfer cross sections are tailor-made for studying "elastic"
electron transport in terms of the two-term solution of the Boltzmann equation:
Not only are the resulting swarm transport coefficients adjustable to the
experimental values, but above all they are calculable very easily because the
unnormalized energy distribution is obtainable analytically. The ample saving
in computational effort is exploited in order to test the Wannier-Robson
"momentum-transfer approximation"; it is found that, in these cases of
resonance-dominated cross sections, the latter method can be so accurate that
it can be used to recover the momentum transfer cross section from experimental
data algebraically. In the margin, a model profile is presented that gives rise
to negative differential conductivity.

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The categories of this paper are: acc-phys
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The categories of this paper are: hep-th
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The categories of this paper are: q-alg
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The categories of this paper are: bayes-an
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The categories of this paper are: mtrl-th
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The categories of this paper are: adap-org
2
The categories of this paper are: math
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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: cond-mat
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The categories of this paper are: comp-gas
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The categories of this paper are: nlin
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The categories of this paper are: atom-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: stat
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The categories of this paper are: cs