Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The azimuthal anisotropy of electrons from heavy flavor decays in
  sqrt(s_NN) = 200 GeV Au-Au collisions by PHENIX   The transverse momentum dependence of the azimuthal anisotropy parameter
v_{2}, the second harmonic of the azimuthal distribution, for electrons at
mid-rapidity (|eta|<0.35) has been measured with the PHENIX detector in Au+Au
collisions at sqrt(s_NN) = 200 GeV with respect to the reaction plane defined
at high rapidities (|eta|=3-4). From the result we have calculated non-photonic
electron v_{2}, which is expected to reflect the heavy-flavor azimuthal
anisotropy, by subtracting v_{2} of electrons from other sources such as photon
conversions, Dalitz decay etc.

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The categories of this paper are: alg-geom
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The categories of this paper are: econ
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The categories of this paper are: atom-ph
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The categories of this paper are: cond-mat
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The categories of this paper are: q-fin
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The categories of this paper are: physics
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The categories of this paper are: q-bio
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The categories of this paper are: eess
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The categories of this paper are: adap-org
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The categories of this paper are: bayes-an
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The categories of this paper are: stat
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The categories of this paper are: acc-phys
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The categories of this paper are: supr-con
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The categories of this paper are: ao-sci
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The categories of this paper are: nucl-th
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The categories of this paper are: gr-qc