Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Vacuum Saturation Hypothesis and QCD Sum Rules   The accuracy of the vacuum saturation hypothesis is discussed using the
examples of vacuum expectation values of four-quark operators and the parameter
$B$, which determines the short-distance contribution to the $K^0 - \bar K^0$
mixing. Note added: The approach based on sum rules in position (x-)space as
elaborated in the paper is relevant and useful tool for the current
phenomenology. In particular, it provides the unique possibility of direct
non-perturbative estimation of the VEV's of four-quark operators renormalized
in any scheme, including the MSbar one.

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The categories of this paper are: chem-ph
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The categories of this paper are: astro-ph
4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
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The categories of this paper are: math-ph
9
The categories of this paper are: nlin
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The categories of this paper are: nucl-ex
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-lat
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The categories of this paper are: comp-gas
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The categories of this paper are: alg-geom
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The categories of this paper are: funct-an
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The categories of this paper are: dg-ga
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The categories of this paper are: adap-org
1
The categories of this paper are: cs
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The categories of this paper are: hep-th