Strong decays of newly observed $D_{sJ}$ states in a constituent quark model with effective Lagrangians

Abstract

The strong decay properties of the newly observed states $D_{sJ}(3040)$, $D_{sJ}(2860)$ and $D_{sJ}(2710)$ are studied in a constituent quark model with quark-meson effective Lagrangians. We find that the $D_{sJ}(3040)$ could be identified as the low mass physical state $|2P_1{>}_L$ ($J^P=1^{+}$) from the $D_s(2^1{P}_1)$-$D_s(2^3{P}_1)$ mixing. The $D_{sJ}(2710)$ is likely to be the low-mass mixed state $|(SD){>}_L$ via the $1^3{D}_1$-$2^3{S}_1$ mixing. In our model, the $D_{sJ}(2860)$ cannot be assigned to any single state with a narrow width and compatible partial widths to $DK$ and $D^{\ast }K$. Thus, we investigate a two-state scenario as proposed in the literature. In our model, one resonance is likely to be the $1^3{D}_3$ ($J^P=3^{-}$), which mainly decays into $DK$. The other resonance seems to be the $|1{D_2}^{\prime }{>}_H$, i.e. the high-mass state in the $1^1{D}_2$-$1^3{D}_2$ mixing with $J^P=2^{-}$, of which the $D^{\ast }K$ channel is its key decay mode. We also discuss implications arising from these assignments and give predictions for their partner states such as $|(SD{)}^{\prime }{>}_H$, $|2P_1^{\prime }{>}_H$, $2^3{P}_0$ and $2^3{P}_2$, which could be helpful for the search for these new states in future experiment.

13 pages, 10 figures, to appear in PRD