Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Production of $X(3940)$ and $X(4160)$ in $B_c$ decays   Considering $X(3940)$ and $X(4160)$ as $\eta_c(3S)$ and $\eta_c(4S)$, we
study the productions of $X(3940)$ and $X(4160)$ in exclusive weak decays of
$B_c$ meson by the improved Bethe-Salpeter(B-S) Method. Using the relativistic
B-S equation and Mandelstam formalism, we calculate the corresponding decay
form factors. The predictions of the corresponding branching ratios are:
$Br(B_c^+\to X(3940)e^+\nu_e)$$=1.0\times10^{-4}$ and $Br(B_c^+\to
X(4160)e^+\nu_e)=2.4\times10^{-5}$. That will provide us a new way to observe
the $X(3940)$ and $X(4160)$ in the future, as well as to improve the knowledge
of $B_c$ meson decay.

1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
7
The categories of this paper are: hep-th
9
The categories of this paper are: nlin
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph
4
The categories of this paper are: cond-mat
24
The categories of this paper are: dg-ga
17
The categories of this paper are: q-fin
12
The categories of this paper are: nucl-th
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn