Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Clustering and ensembles inequivalence in the phi-4 and phi-6 mean-field
  Hamiltonian models   We investigate a model of globally coupled conservative oscillators. Two
different algebraic potentials are considered that display in the canonical
ensemble either a second ($\phi^{4}$) or both a second and a first order phase
transition separated by tricritical points ($\phi^{6}$). The stability of
highly clustered states appearing in the low temperature/energy region is
studied both analytically and numerically for the $\phi^{4}$-model. Moreover,
long-lived out-of-equilibrium states appear close to the second order phase
transition when starting with "water-bag" initial conditions, in analogy with
what has been found for the Hamiltonian Mean Field (HMF) model. The
microcanonical simulations of the $\phi^{6}$-model show strong hysteretic
effects and metastability near the first-order phase transition and a narrow
region of negative specific heat.

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The categories of this paper are: mtrl-th
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The categories of this paper are: plasm-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: nucl-th
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The categories of this paper are: nlin
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The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
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The categories of this paper are: solv-int
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The categories of this paper are: atom-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: funct-an
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The categories of this paper are: eess
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-th
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The categories of this paper are: astro-ph