Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum Multiple Scattering: Eigenmode Expansion and Its Applications to
  Proximity Resonance   We show that for a general system of N s-wave point scatterers, there are
always N eigenmodes. These eigenmodes or eigenchannels play the same role as
spherical harmonics for a spherically symmetric target--they give a phase shift
only. In other words, the T matrix of the system is of rank N and the
eigenmodes are eigenvectors corresponding to non-0 eigenvalues of the T matrix.
The eigenmode expansion approach can give insight to the total scattering cross
section; the position, width, and superradiant or subradiant nature of
resonance peaks; the unsymmetric Fano lineshape of sharp proximity resonance
peaks based on the high energy tail of a broad band; and other properties.
Off-resonant eigenmodes for identical proximate scatterers are approximately
angular momentum eigenstates.

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The categories of this paper are: hep-ex
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The categories of this paper are: q-alg
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The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio
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The categories of this paper are: bayes-an
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
0
The categories of this paper are: hep-ph
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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: eess
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The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin