Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Depletion and fluctuations of a trapped dipolar Bose-Einstein condensate
  in the roton regime   We consider the non-condensate density and density fluctuations of a trapped
dipolar Bose-Einstein condensate, focusing on the regime where a roton-like
excitation spectrum develops. Our results show that a characteristic peak in
the non-condensate density occurs at trap center due to the rotons. In this
regime we also find that the anomalous density becomes positive and peaked,
giving rise to enhanced density fluctuations. We calculate the non-condensate
density in momentum space and show that a small momentum halo is associated
with the roton excitations.

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The categories of this paper are: math-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: comp-gas
2
The categories of this paper are: math
30
The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph
25
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: eess
32
The categories of this paper are: atom-ph
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The categories of this paper are: q-fin
29
The categories of this paper are: funct-an
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The categories of this paper are: nucl-th
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The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
3
The categories of this paper are: physics