Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Approach to equilibrium of quarkonium in quark-gluon plasma   We calculate the dissociation and recombination rates of $\Upsilon(1S)$ in
quark-gluon plasma by using potential non-relativistic QCD. We then study the
dynamical in-medium evolution of the $b\bar{b}-\Upsilon$ system in a periodic
box via the Boltzmann equation and explore how the system reaches equilibrium.
We find that interactions between the free heavy quarks and the medium are
necessary for the system to reach equilibrium. We find that the angular
distribution of $\Upsilon(1S)$ probes the stages at which recombination occurs.
Finally, we study the system under a longitudinal expansion and show that
different initial conditions evolve to distinct final ratios of hidden and open
$b$ flavors. We argue that experimental measurements of the ratio could address
open questions in the quarkonium production in heavy ion collisions.

5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
35
The categories of this paper are: mtrl-th
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The categories of this paper are: astro-ph
13
The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
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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: hep-lat
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The categories of this paper are: q-fin
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The categories of this paper are: chao-dyn
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The categories of this paper are: cond-mat
34
The categories of this paper are: chem-ph