We examine the possibility to extract information about the DN and DbarN interactions from the pbar d to D Dbar N reaction. We utilize the notion that the open-charm mesons are first produced in the annihilation of the antiproton on one nucleon in the deuteron and subsequently rescatter on the other (the spectator) nucleon. The latter process is then exploited for investigating the DN and DbarN interactions. We study different methods for isolating the contributions from the D^0p and D^-p rescattering terms.
In two recent reactions by Belle producing $Dbar D$ and $Dbar D^*$ meson pairs, peaks above threshold have been measured in the differential cross sections, possibly indicating new resonances in these channels. We want to study such reactions from th
e point of view that the $D$ meson pairs are produced from already known or predicted resonances below threshold. Our study shows that the peak in the $Dbar D^*$ production is not likely to be caused by the X(3872) resonance, but the peak seen in $Dbar D$ invariant mass can be well described if the $Dbar D$ pair comes from the already predicted scalar X(3700) resonance.
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.
We analyze two recent reactions of Belle, producing $Dbar D$ and $Dbar D^*$ states that have an enhancement of the invariant $Dbar D$, $Dbar D^*$ mass distribution close to threshold, from the point of view that they might be indicative of the existe
nce of a hidden charm scalar and an axial vector meson states below $Dbar D$ or $Dbar D^*$ thresholds, respectively. We conclude that the data is compatible with the existing prediction of a hidden charm scalar meson with mass around 3700 MeV, though other possibilities cannot be discarded. The peak seen in the $Dbar D^*$ spectrum above threshold is, however, unlikely to be due to a threshold enhancement produced by the presence, below threshold, of the hidden charm axial vector meson X(3872).
The appearance of some papers dealing with the $K^- d to pi Sigma n$ reaction, with some discrepancies in the results and a proposal to measure the reaction at forward $n$ angles at J-PARC justifies to retake the theoretical study with high precision
to make accurate predictions for the experiment and extract from there the relevant physical information. We do this in the present paper showing results using the Watson approach and the truncated Faddeev approach. We argue that the Watson approach is more suitable to study the reaction because it takes into account the potential energy of the nucleons forming the deuteron, which is neglected in the truncated Faddeev approach. Predictions for the experiment are done as well as spectra with the integrated neutron angle.
In this article, we assume that there exist the pseudoscalar $Dbar{D}_{s0}^*(2317)$ and $D^*bar{D}_{s1}^*(2460)$ molecular states $Z_{1,2}$ and construct the color singlet-singlet molecule-type interpolating currents to study their masses with the QC
D sum rules. In calculations, we consider the contributions of the vacuum condensates up to dimension-10 and use the formula $mu=sqrt{M_{X/Y/Z}^{2}-left(2{mathbb{M}}_{c}right)^{2}}$ to determine the energy scales of the QCD spectral densities. The numerical results, $M_{Z_1}=4.61_{-0.08}^{+0.11},text{GeV}$ and $M_{Z_2}=4.60_{-0.06}^{+0.07},text{GeV}$, which lie above the $Dbar{D}_{s0}^*(2317)$ and $D^*bar{D}_{s1}^*(2460)$ thresholds respectively, indicate that the $Dbar{D}_{s0}^*(2317)$ and $D^*bar{D}_{s1}^*(2460)$ are difficult to form bound state molecular states, the $Z_{1,2}$ are probably resonance states.