Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurement of the Dynamical Structure Factor of a 1D Interacting Fermi
  Gas   We present measurements of the dynamical structure factor $S(q,\omega)$ of an
interacting one-dimensional (1D) Fermi gas for small excitation energies. We
use the two lowest hyperfine levels of the $^6$Li atom to form a
pseudo-spin-1/2 system whose s-wave interactions are tunable via a Feshbach
resonance. The atoms are confined to 1D by a two-dimensional optical lattice.
Bragg spectroscopy is used to measure a response of the gas to density
("charge") mode excitations at a momentum $q$ and frequency $\omega$. The
spectrum is obtained by varying $\omega$, while the angle between two laser
beams determines $q$, which is fixed to be less than the Fermi momentum
$k_\textrm{F}$. The measurements agree well with Tomonaga-Luttinger theory.

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The categories of this paper are: gr-qc
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The categories of this paper are: plasm-ph
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The categories of this paper are: eess
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-ex
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The categories of this paper are: adap-org
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The categories of this paper are: astro-ph
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The categories of this paper are: stat
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The categories of this paper are: q-alg
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The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
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The categories of this paper are: cs
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The categories of this paper are: cmp-lg
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The categories of this paper are: econ
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The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th