Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userPredicition for the decay width of a charged state near the $D_sbar{D}^*/D^*_sbar{D}$ threshold
158
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
Very recently it was predicted the existence of a charged state near the $D_sbar{D}^*/D^*_sbar{D}$ threshold. This state, that we call $Z_{cs}^+$, would be the strange partner of the recently observed $Z_c^pm(3900)$. Using standard techniques of QCD sum rules, we evaluate the three-point function for the vertices $Z_{cs}^+ , J/psi , K^+$, $Z_{cs}^+ , eta_c , K^{*+}$ and $Z_{cs}^+ , D_s^+bar{D}^{*0}$ and we make predictions for the corresponding decay widths in these channels.
rate research
Read More
Recently, a new structure $Y(4626)$ was reported by the Belle Colloboration in the process $e^+e^-to D_s^+D_{s1}(2536)^-$. In this work, we propose an assignment of the $Y(4626)$ as a ${D}^*_sbar{D}_{s1}(2536)$ molecular state, which decays into the $D_s^+D_{s1}(2536)^-$ channel through a coupling between ${D}^*_sbar{D}_{s1}(2536)$ and ${D}_sbar{D}_{s1}(2536)$ channels. With the help of the heavy quark symmetry, the potential of the interaction ${D}^*_sbar{D}_{s1}(2536)-{D}_sbar{D}_{s1}(2536)$ is constructed within the one-boson-exchange model, and inserted into the quasipotential Bethe-Salpeter equation. The pole of obtained scattering amplitude is searched for in the complex plane, which corresponds to a molecular state from the interaction ${D}^*_sbar{D}_{s1}(2536)-{D}_sbar{D}_{s1}(2536)$. The results suggest that a pole is produced near the ${D}^*_sbar{D}_{s1}(2536)$ threshold, which exhibits as a peak in the invariant mass spectrum of the ${D}_sbar{D}_{s1}(2536)$ channel at about 4626 MeV. It obviously favors the $Y(4265)$ as a ${D}^*_sbar{D}_{s1}(2536)$ molecular state. In the same model, other molecular states from the interaction ${D}^*_sbar{D}_{s1}(2536)-{D}_sbar{D}_{s1}(2536)$ are also predicted, which can be checked in future experiments.
In the present work, we construct the color-singlet-color-singlet type four-quark currents to investigate the $D_sbar{D}_{s1}$ and $D_s^*bar{D}_{s0}^*$ tetraquark molecular states with the $J^{PC}=1^{--}$ and $1^{-+}$ via the QCD sum rules, and obtain satisfactory results. We can search for the $D_sbar{D}_{s1}$ and $D_s^*bar{D}_{s0}^*$ tetraquark molecular states with the $J^{PC}=1^{--}$ and $1^{-+}$ at the BESIII and Belle II in the future.
A model for the p d --> p d eta reaction published earlier, including the final state interaction (FSI) of all particles, is revisited to investigate the low energy data on this reaction. The three body problem of p-d-eta scattering in the final state is approximated in terms of pairwise interactions between the three particles in the final state. Apart from a comparison with some preliminary data, two new findings relevant to the near threshold data analysis are reported. The first one points toward the limitations of an FSI factor used conventionally to extract the eta-deuteron scattering length and infer subsequently on the existence of eta-mesic states. The second result emphasizes the role of the $p-d$ FSI and the strong Coulomb repulsion near threshold. Finally, a comparison of the above model calculation with low energy data, excludes very large eta-nucleon scattering lengths.
Using proton-proton collision data, corresponding to an integrated luminosity of 9$fb^{-1}$, collected with the~LHCb detector between 2011 and 2018, a new narrow charmonium state, the $X(3842)$ resonance, is observed in the decay modes $X(3842)rightarrow D^0bar{D}^0$ and $X(3842)rightarrow D^+D^-$. The mass and the natural width of this state are measured to be begin{eqnarray*} m_{X(3842)} & = & 3842.71 pm 0.16 pm 0.12 MeV/c^2,, Gamma_{X(3842)} & = & 2.79 pm 0.51 pm 0.35 MeV,, end{eqnarray*} where the first uncertainty is statistical and the~second is systematic. The observed mass and narrow natural width suggest the~interpretation of the new state as the~unobserved spin obreakdash-3 $psi_3mathrm{left(1^3D_3right)}$ charmonium state. In addition, prompt hadroproduction of the $psi(3770)$~and $chi_{c2}(3930)$ states is observed for the first time, and the parameters of these~states are measured to be begin{eqnarray*} m_{psi(3770)} & = & 3778.1 pm 0.7 pm 0.6 MeV/c^2,, m_{chi_{c2}(3930)} & = & 3921.9 pm 0.6 pm 0.2 MeV/c^2,, Gamma_{chi_{c2}(3930)} & = &36.6 pm 1.9 pm 0.9 MeV,, end{eqnarray*} where the first uncertainty is statistical and the~second is systematic.
We have investigated the process of $Lambda_bto Lambda Dbar{D}$, by taking into account the contributions from the $s$-wave $Dbar{D}$ interaction within the coupled-channel unitary approach, and the intermediate $psi(3770)$ resonance. In addition to the peak of the $psi(3770)$, an enhancement near the $Dbar{D}$ mass threshold is found in the $Dbar{D}$ invariant mass distributions, which should be the reflection of the $Dbar{D}$ bound state. We would like to encourage our experimental colleagues to measure the $Dbar{D}$ invariant mass distribution of the $Lambda_bto Lambda Dbar{D}$ process, which is crucial to search for the $Dbar{D}$ bound state and to understand the heavy-hadron heavy-hadron interactions.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
