The strong vertices of charmed mesons DD, D∗D^{*} and charmonia J/ψJ/\psi, ηc\eta_{c}

In this work, the strong form factors and coupling constants of the vertices $DDJ/\psi$, $DD^{*}J/\psi$, $D^{*}D^{*}J/\psi$, $DD^{*}\eta_{c}$, $D^{*}D^{*}\eta_{c}$ are calculated within the framework of the QCD sum rule. For each vertex, we analyze the form factor considering all possible off-shell cases and the contributions of the vacuum condensate terms $\langle\overline{q}q\rangle$, $\langle\overline{q}g_{s}\sigma Gq\rangle$, $\langle g_{s}^{2}G^{2}\rangle$, $\langle f^{3}G^{3}\rangle$ and $\langle\overline{q}q\rangle\langle g_{s}^{2}G^{2}\rangle$. Then, the form factors are fitted into analytical functions $g(Q^2)$ and are extrapolated into time-like regions to get the strong coupling constants. Finally, the strong coupling constants are obtained by using on-shell cases of the intermediate mesons($Q^2=-m^2$). The results are as follows, $g_{DDJ/\psi}=5.01^{+0.58}_{-0.16}$, $g_{DD^{*}J/\psi}=3.55^{+0.20}_{-0.21}$GeV$^{-1}$, $g_{D^{*}D^{*}J/\psi}=5.10^{+0.59}_{-0.43}$, $g_{DD^{*}\eta_{c}}=3.68^{+0.39}_{-0.11}$ and $g_{D^{*}D^{*}\eta_{c}}=4.87^{+0.42}_{-0.40}$GeV$^{-1}$

The strong vertices of bottom mesons BB, B∗B^{*} and bottomonia Υ\Upsilon, ηb\eta_{b}

In this article, the strong coupling constants of vertices $BB\Upsilon$, $BB^{*}\Upsilon$, $B^{*}B^{*}\Upsilon$, $BB^{*}\eta_{b}$ and $B^{*}B^{*}\eta_{b}$ are analyzed in the framework of QCD sum rules. In this work, all possible off-shell cases and the contributions of vacuum condensate terms including $\langle\overline{q}q\rangle$, $\langle\overline{q}g_{s}\sigma Gq\rangle$, $\langle g_{s}^{2}G^{2}\rangle$, $\langle f^{3}G^{3}\rangle$ and $\langle\overline{q}q\rangle\langle g_{s}^{2}G^{2}\rangle$ are considered. The momentum dependent strong coupling constants are first calculated and then are fitted into analytical functions $g(Q^{2})$ which are used to extrapolate into time-like regions to obtain the final values of strong coupling constants. The final results are $g_{BB\Upsilon}=40.67^{+7.55}_{-4.20}$, $g_{BB^{*}\Upsilon}=11.58^{+2.19}_{-1.09}$ GeV$^{-1}$, $g_{B^{*}B^{*}\Upsilon}=57.02^{+5.32}_{-5.31}$, $g_{BB^{*}\eta_{b}}=23.39^{+4.74}_{-2.30}$ and $g_{B^{*}B^{*}\eta_{b}}=12.49^{+2.12}_{-1.35}$ GeV$^{-1}$. These strong coupling constants are important input parameters which reflect the dynamic properties of the interactions among the mesons and quarkonia

Analysis of the strong vertices of ΣcΔD∗\Sigma_{c}\Delta D^{*} and ΣbΔB∗\Sigma_{b}\Delta B^{*} in QCD sum rules

In this work, we analyze the strong vertices $\Sigma_{c}\Delta D^{*}$ and $\Sigma_{b}\Delta B^{*}$ using the three-point QCD sum rules under the tensor structures $i\epsilon^{\rho\tau\alpha\beta}p_{\alpha}p_{\beta}$, $p^{\rho}p'^{\tau}$ and $p^{\rho}p^{\tau}$. We firstly calculate the momentum dependent strong coupling constants $g(Q^{2})$ by considering contributions of the perturbative part and the condensate terms $\langle\overline{q}q\rangle$, $\langle g_{s}^{2}GG \rangle$, $\langle\overline{q}g_{s}\sigma Gq\rangle$ and $\langle\overline{q}q\rangle^{2}$. By fitting these coupling constants into analytical functions and extrapolating them into time-like regions, we then obtain the on-shell values of strong coupling constants for these vertices. The results are $g_{1\Sigma_{c}\Delta D^{*}}=5.13^{+0.39}_{-0.49}$ GeV$^{-1}$, $g_{2\Sigma_{c}\Delta D^{*}}=-3.03^{+0.27}_{-0.35}$ GeV$^{-2}$, $g_{3\Sigma_{c}\Delta D^{*}}=17.64^{+1.51}_{-1.95}$ GeV$^{-2}$, $g_{1\Sigma_{b}\Delta B^{*}}=20.97^{+2.15}_{-2.39}$ GeV$^{-1}$, $g_{2\Sigma_{b}\Delta B^{*}}=-11.42^{+1.17}_{-1.28}$ GeV$^{-2}$ and $g_{3\Sigma_{b}\Delta B^{*}}=24.87^{+2.57}_{-2.82}$ GeV$^{-2}$. These strong coupling constants are important parameters which can help us to understand the strong decay behaviors of hadrons

The SS- and PP-wave fully charmed tetraquark states and their radial excitations

Inspired by recent progresses in observations of the fully charmed tetraquark states by LHCb, CMS, and ATLAS Collaborations, we perform a systematic study of the ground states and the first radial excitations of the $S$- and $P$-wave $\mathrm{cc}\bar{\mathrm{c}}\bar{\mathrm{c}}$ system. Their mass spectra, root mean square(r.m.s.) radii and radial density distributions are studied with the relativized quark model. The calculations show that there is no stable bound states for the full-charmed tetraquark states, and the r.m.s. radii of these tetraquark states are smaller than 1 fm. Our results support assigning X(6600) structure, $M_{X(6600)}=6552\pm10\pm12$ MeV, as one of the $0^{++}$(1$S$) and $2^{++}$(1$S$) states or their mixtures. Another structure also named as X(6600) by CMS Collaboration, $M_{X(6600)}=6.62\pm0.03^{+0.02}_{-0.01}$ GeV, may arise from the lowest 1$P$ states with $J^{PC}$=$0^{-+}$, $1^{-+}$, and $2^{-+}$. The possible assignments for X(6900) include the $0^{++}$(2$S$), $2^{++}$(2$S$) states, and the highest 1$P$ state with $J^{PC}=0^{-+}$. As for X(7200), it can be interpreted as one of the highest 2$P$ states with $J^{PC}=0^{-+}$, $1^{-+}$, and $2^{-+}$, and the 3$S$ states can not be completely excluded from the candidates.Comment: to be published in European Physical Journal

Strong decay properties of single heavy baryons ΛQ\Lambda_{Q}, ΣQ\Sigma_{Q} and ΩQ\Omega_{Q}

Motivated by recent progresses in experiments in searching for the $\Omega_{c}$ baryons, we systematically analyze the strong decay behaviors of single heavy baryons $\Lambda_{Q}$, $\Sigma_{Q}$ and $\Omega_{Q}$. The two-body strong decay properties of $S$-wave, $P$-wave and some $D$-wave states are studied with the $^{3}P_{0}$ model. The results support assigning the recently observed $\Omega_{c}(3185)$ and $\Omega_{c}(3327)$ as the 2S($\frac{3}{2}^{+}$) and 1D($\frac{3}{2}^{+}$) states, respectively. In addition, the quantum numbers of many other experimentally observed baryons are also suggested according to their strong decays. Finally, some baryons which have good potentials to be observed in experiments are predicted and the possible decay channels for searching for these predicted states are also suggested.Comment: arXiv admin note: substantial text overlap with arXiv:2206.0812

Systematic analysis of doubly charmed baryons Ξcc\Xi_{cc} and Ωcc\Omega_{cc}

In this work, we perform a systematic study of the mass spectra, the root mean square(r.m.s.) radii and the radial density distributions of the doubly charmed baryons $\Xi_{cc}$ and $\Omega_{cc}$. The calculations are carried out in the frame work of Godfrey-Isgur (GI) relativized quark model, where the baryon is regarded as a real three-body system of quarks. Our results show that the excited energy of doubly charmed baryon with $\rho$-mode is lower than those of the $\lambda$-mode and $\lambda$-$\rho$ mixing mode, which indicates that the lowest state is dominated by the $\rho$-mode. According to this conclusion, we systematically investigate the mass spectra, the r.m.s. radii of the ground and excited states($1S\sim4S$, $1P\sim4P$, $1D\sim4D$, $1F\sim4F$ and $1G\sim4G$) with $\rho$-mode. Using the wave functions obtained from quark model, we also study the radial density distributions. Finally, with the predicated mass spectra, the Regge trajectories of $\Xi_{cc}$ and $\Omega_{cc}$ in the ($J$,$M^{2}$) plane are constructed, and the slopes, intercepts are determined by linear fitting. It is found that model predicted masses fit nicely to the constructed Regge trajectories.Comment: arXiv admin note: text overlap with arXiv:2206.0812

Systematic analysis of strange single heavy baryons Ξc\Xi_{c} and Ξb\Xi_{b}

Motivated by the experimental progress in the study of heavy baryons, we investigate the mass spectra of strange single heavy baryons in the $\lambda$-mode, where the relativistic quark model and the infinitesimally shifted Gaussian basis function method are employed. It is shown that the experimental data can be well reproduced by the predicted masses. The root mean square radii and radial probability density distributions of the wave functions are analyzed in detail. Meanwhile, the mass spectra allow us to successfully construct the Regge trajectories in the $(J,M^{2})$ plane. We also preliminarily assign quantum numbers to the recently observed baryons, including $\Xi_{c}(3055)$, $\Xi_{c}(3080)$, $\Xi_{c}(2930)$, $\Xi_{c}(2923)$, $\Xi_{c}(2939)$, $\Xi_{c}(2965)$, $\Xi_{c}(2970)$, $\Xi_{c}(3123)$, $\Xi_{b}(6100)$, $\Xi_{b}(6227)$, $\Xi_{b}(6327)$ and $\Xi_{b}(6333)$. At last, the spectral structure of the strange single heavy baryons is shown. Accordingly, we predict several new baryons that might be observed in forthcoming experiments.Comment: 27 pages, 11 figures, 8 table