Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Resolving the HBT Puzzle in Relativistic Heavy Ion Collision   Two particle correlation data from the Relativistic Heavy Ion Collider have
provided detailed femtoscopic information describing the space-time structure
of the emission of pions. This data had avoided description with
hydrodynamic-based approaches, in contrast to the success of hydrodynamics in
reproducing other classes of observables. This failure has inspired the term
``HBT puzzle'', where HBT refers to femtoscopic studies which were originally
based on Hanbury-Brown Twiss interferometry. Here, the puzzle is shown to
originate not from a single shortcoming of hydrodynamic models, but the
combination of several effects: mainly including pre-thermalized acceleration,
using a stiffer equation of state, and adding viscous corrections.

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The categories of this paper are: econ
34
The categories of this paper are: chem-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: atom-ph
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The categories of this paper are: hep-lat
3
The categories of this paper are: physics
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The categories of this paper are: mtrl-th
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The categories of this paper are: math-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: q-fin
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The categories of this paper are: hep-ex
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The categories of this paper are: stat
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The categories of this paper are: bayes-an
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The categories of this paper are: adap-org
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The categories of this paper are: q-alg
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The categories of this paper are: dg-ga