Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: $K^{\ast}(892)^0$ and $\bar{K}^{\ast}(892)^0$ production in central
  Pb+Pb, Si+Si, C+C and inelastic p+p collisions at 158$A$~GeV   Production of the $K^{\ast}(892)^0$ and $\bar{K}^{\ast}(892)^0$ resonances
was studied via their $K^+ \pi^-$ and $K^- \pi^+$ decay modes in central Pb+Pb,
Si+Si, C+C and inelastic p+p collisions at 158\agev ($\sqrt{s_{NN}}$ = 17.3
GeV) with the NA49 detector at the CERN SPS. Transverse momentum and rapidity
distributions were measured and total yields were estimated. The yield of
$K^{\ast}$ exceeds that of $\bar{K}^{\ast}$ by about a factor of two in
nucleus-nucleus reactions. The total yield ratios $< K^{\ast} >/< K^+ >$ and $<
\bar{K}^{\ast} >/< K^->$ are strongly suppressed in central Pb+Pb compared to
p+p, C+C and Si+Si collisions in agreement with the expected attenuation of
these short-lived resonance states in the hadronic phase of the expanding
fireball. The UrQMD model, although incorporating such a scenario, does not
provide a quantitative description of the experimental results. The statistical
hadron gas model assuming the same freeze-out parameters for stable hadrons and
resonances overestimates the $< K^{\ast} >/< K >$ ratios in central Pb+Pb
collisions by about a factor of 2.5.

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The categories of this paper are: math
34
The categories of this paper are: chem-ph
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The categories of this paper are: gr-qc
4
The categories of this paper are: cond-mat
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The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
24
The categories of this paper are: dg-ga
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The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
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The categories of this paper are: nlin
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The categories of this paper are: astro-ph
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: physics
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The categories of this paper are: stat
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The categories of this paper are: math-ph