Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Radiative $B_c$ meson decays $B_c \to \gamma u\bar{d}$   Inclusive radiative decays $B_c\to\gamma u\bar{d}$ are considered. It is
shown that photon emission allows one to bypass the chiral suppression and
leads the increase of the branching fraction by about four orders of magnitude.
The estimates of exclusive decay branching fractions of $B_c$ meson into
different sets of $\pi$ mesons are also given.

23
The categories of this paper are: solv-int
36
The categories of this paper are: cmp-lg
17
The categories of this paper are: q-fin
22
The categories of this paper are: chao-dyn
2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
34
The categories of this paper are: chem-ph
21
The categories of this paper are: adap-org
28
The categories of this paper are: alg-geom