Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Charm-loop effect in $B \to K^{(*)} \ell^{+} \ell^{-}$ and $B\to
  K^*\gamma$   We calculate the long-distance effect generated by the four-quark operators
with $c$-quarks in the $B\to K^{(*)} \ell^+\ell^-$ decays. At the lepton-pair
invariant masses far below the $\bar{c}c$-threshold, $q^2\ll 4m_c^2$, we use
OPE near the light-cone. The nonfactorizable soft-gluon emission from
$c$-quarks is cast in the form of a nonlocal effective operator. The $B\to
K^{(*)}$ matrix elements of this operator are calculated from the QCD
light-cone sum rules with the $B$-meson distribution amplitudes. As a
byproduct, we also predict the charm-loop contribution to $B\to K^*\gamma$
beyond the local-operator approximation. To describe the charm-loop effect at
large $q^2$, we employ the hadronic dispersion relation with $\psi=J/\psi,\psi
(2S), ...$ contributions, where the measured $ B\to K^{(*)}\psi $ amplitudes
are used as inputs. Matching this relation to the result of QCD calculation
reveals a destructive interference between the $J/\psi$ and $\psi(2S)$
contributions. The resulting charm-loop effect is represented as a
$q^2$-dependent correction $\Delta C_9(q^2)$ to the Wilson coefficient $C_9$.
Within uncertainties of our calculation, at $q^2$ below the charmonium region
the predicted ratio $\Delta C_9(q^2)/C_9$ is $\leq 5% $ for $B\to K
\ell^+\ell^-$, but can reach as much as 20% for $B\to K^*\ell^+\ell^-$, the
difference being mainly caused by the soft-gluon contribution.

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The categories of this paper are: econ
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The categories of this paper are: chem-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: dg-ga
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The categories of this paper are: quant-ph
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The categories of this paper are: eess
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The categories of this paper are: astro-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: chao-dyn
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The categories of this paper are: nucl-ex
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The categories of this paper are: q-fin
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The categories of this paper are: math
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The categories of this paper are: alg-geom
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The categories of this paper are: cond-mat
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The categories of this paper are: stat