Speaker
Description
The hidden-charm pentaquark structures (P_c(4312)), (P_c(4440)), and
(P_c(4457)) lie close to the (\Sigma_c \bar{D}^{()}) thresholds and are
frequently interpreted as hadronic molecular candidates. We investigate their
open-charm decay patterns by treating these states as (S)-wave
(\Sigma_c \bar{D}^{()}) configurations. The short-range transitions
%
[
\Sigma_c \bar{D}^{()}
\rightarrow
\Lambda_c \bar{D}^{()},
]
%
leading to the (\Lambda_c \bar{D}) and (\Lambda_c \bar{D}^{*}) final
states, are evaluated within the Born-order quark-interchange model. The
transition amplitudes are constructed from the relevant prior and post
quark-rearrangement diagrams, including their spin, flavor, color, and spatial
matrix elements.
The results exhibit a pronounced channel hierarchy: the
(\Lambda_c \bar{D}^{}) mode is generally favored, whereas the
(\Lambda_c \bar{D}) contribution is strongly suppressed. For the
(\Sigma_c \bar{D}^{}) molecular candidates, the predicted decay patterns
are sensitive to the (J^{P}=\frac{1}{2}^{-}) and
(J^{P}=\frac{3}{2}^{-}) assignments. In particular, the (L=0) transition
to (\Lambda_c \bar{D}) vanishes for the (J^{P}=\frac{3}{2}^{-})
assignment within the present treatment. These spin-dependent patterns
indicate that open-charm final states can provide complementary information
for distinguishing possible molecular assignments of the observed (P_c)
structures. The calculated partial widths represent the short-range
quark-interchange contributions; long-range mechanisms and coupled-channel
effects are not included.
