Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The neutral kaon mixing parameter B_K from unquenched mixed-action
  lattice QCD   We calculate the neutral kaon mixing parameter B_K in unquenched lattice QCD
using asqtad-improved staggered sea quarks and domain-wall valence quarks. We
use the "2+1" flavor gauge configurations generated by the MILC Collaboration,
and simulate with multiple valence and sea quark masses at two lattice spacings
of a ~ 0.12 fm and a ~ 0.09 fm. We match the lattice determination of B_K to
the continuum value using the nonperturbative method of Rome-Southampton, and
extrapolate B_K to the continuum and physical quark masses using mixed action
chiral perturbation theory. The "mixed-action" method enables us to control all
sources of systematic uncertainty and therefore to precisely determine B_K; we
find a value of B_K^{MSbar, NDR}(2 GeV) = 0.527(6)(20), where the first error
is statistical and the second is systematic.

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The categories of this paper are: q-fin
9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
24
The categories of this paper are: dg-ga
31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
15
The categories of this paper are: nucl-ex
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The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
23
The categories of this paper are: solv-int
10
The categories of this paper are: q-bio
4
The categories of this paper are: cond-mat
8
The categories of this paper are: hep-ex