Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Heavy-to-light chromomagentic matrix element   We report the computation of the matrix element of the chromomagnetic
operator of the flavour changing neutral current (FCNC)-type between a $B$- or
$D$-meson state and a light hadron and off-shell photon. The computation is
carried out by using the method of light-cone sum rules (LCSR). It is found
that the matrix element exhibits a large strong phase for which we give a long
distance interpretation. The analytic structure of the correlation function in
use admits a complex anomalous threshold on the physical sheet, the meaning and
handling of which within the sum rule approach is discussed. We compare our
results to QCD factorisation for which spectator photon emission is end-point
divergent.

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The categories of this paper are: q-fin
18
The categories of this paper are: econ
16
The categories of this paper are: stat
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
30
The categories of this paper are: q-alg
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
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The categories of this paper are: comp-gas
1
The categories of this paper are: cs
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The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
24
The categories of this paper are: dg-ga
33
The categories of this paper are: plasm-ph