Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Radiative Leptonic Decays of $B_c $ Meson   To the leading order, the radiative leptonic decays $B_c \to \gamma \ell \bar
\nu$ ($ \ell=e, \mu$) are studied carefully. In the study, a non-relativistic
constituent quark model and the effective Lagrangian for the heavy flavour
decays are used. As a result, the branching ratios turn out to be of the orders
of $10^{-5}$ for $B_c \to \gamma \mu \bar \nu $ or for $B_c \to \gamma e \bar
\nu $. Based on this study, we point out the decays being accessible
experimentally at the future LHC, and the possibility to determine the decay
constant $f_{B_c}$ through the radiative decays.

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The categories of this paper are: cond-mat
18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
2
The categories of this paper are: math
36
The categories of this paper are: cmp-lg
17
The categories of this paper are: q-fin
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci