Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Isospin analysis of $B\to D^*\bar{D}K$ and the absence of the
  $Z_c(3900)$ in $B$ decays   We study the isospin amplitudes in the exclusive $B$ to $D^*\bar{D}K$ decay
process and fit the available $D^{*0}\bar{D}^0$ invariant mass distributions
near threshold. The analysis demonstrates that the production of the isospin
triplet $D^*\bar{D}$ state is highly suppressed compared to the isospin singlet
one. That explains why the $Z_c(3900)$ has not been found in $B$ decays. In
addition, the production of the negative charge-parity state might be further
suppressed in the heavy quark limit. These two reasons which are based on the
molecular assumption offer the first explanation why the $Z_c(3900)$ is absent
in $B$ decays. Further studies of the absence from both the experimental and
the theoretical side is extremely important for understanding the nature of the
$X(3872)$ and the $Z_c(3900)$.

22
The categories of this paper are: chao-dyn
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
26
The categories of this paper are: bayes-an
6
The categories of this paper are: astro-ph
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
16
The categories of this paper are: stat
12
The categories of this paper are: nucl-th
3
The categories of this paper are: physics
8
The categories of this paper are: hep-ex
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
2
The categories of this paper are: math
14
The categories of this paper are: math-ph