Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Three-loop matching of the vector current   We evaluate the three-loop corrections to the matching coefficient of the
vector current between Quantum Chromodynamics (QCD) and non-relativistic QCD.
The result is presented in the MSbar scheme where large perturbative
corrections are observed. The implications on the threshold production of top
quark pairs are briefly discussed.

8
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: econ
14
The categories of this paper are: math-ph
25
The categories of this paper are: patt-sol
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
37
The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
4
The categories of this paper are: cond-mat
12
The categories of this paper are: nucl-th