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In this work, we investigate the heavy-flavor conserving weak decays of charmed baryons, specifically the processes $\Xi_{c} \to \Lambda_{c} \pi$ and $\Omega_{c} \to \Xi_{c} \pi$, where the pole model is employed to account for the nonfactorizable contributions. Additionally, the nonperturbative parameters involved are determined within the framework of the nonrelativistic quark model, utilizing exact baryon wave functions obtained by solving the Schr\"{o}dinger equation with a nonrelativistic potential. By considering the mixing angle $\theta \in (24.4^\circ, 32.4^\circ)$ for $\Xi_{c}-\Xi_{c}^{\prime}$ mixing, we find that the experimental data can be effectively reproduced. Furthermore, we estimate the branching ratios: $\mathcal{B}(\Xi_{c}^{+} \to \Lambda_{c}^{+} \pi^{0}) = (8.69 \sim 9.79) \times 10^{-3}$, $\mathcal{B}(\Omega_{c}^{0} \to \Xi_{c}^{+} \pi^{-}) = (11.3 \sim 12.1) \times 10^{-3}$, and $\mathcal{B}(\Omega_{c}^{0} \to \Xi_{c}^{+} \pi^{0}) = (4.67 \sim 5.23) \times 10^{-3}$. These predictions can be tested in ongoing experiments at LHCb, Belle II, and BESIII., Comment: 11 pages, 5 figures, 8 tables

Inspired by the newly observed $T_{c\bar{s}}$ state in the $D_{s1}(2460)^{+} \rightarrow D_{s}^{+}\pi^{+}\pi^{-}$ reaction by the LHCb Collaboration, we investigate the amplitude in this decay to explore the origin and properties of this open-charm tetraquark state based on the final state interaction. The invariant mass distributions of $D_{s}^{+}\pi^{+}$ and $\pi^{+}\pi^{-}$ are well reproduced by the $S$-wave scattering amplitudes of the coupled channel systems $D_{s}\pi$ and $\pi\pi$. However, either only the tree-level contribution nor both the tree-level and $\pi\pi$ coupled channel scattering contributions can not to describe the experimental data well, which indicates that the $D_{s}\pi$ coupled channel scattering is required. We find the $T_{c\bar{s}}$ and $f_{0}(500)$ resonances are dynamically generated from the pseudoscalar-pseudoscalar meson interaction within the chiral unitary approach. In addition, we find the corresponding poles and also calculate the $S$-wave scattering length for the $DK$ channel, which is on the same scale as the result extracted from the experiment. We propose that the $T_{c\bar{s}}$ and $f_{0}(500)$ resonances in the $D_{s1}(2460)^{+} \rightarrow D_{s}^{+}\pi^{+}\pi^{-}$ reaction are molecular type particles.

In this work, we study the flavor-changing neutral-current process $B_{c}\to{D}_{s}^{*}(\to{D}_{s}\pi)\ell^{+}\ell^{-}$ ($\ell$= $e$, $\mu$, $\tau$). The relevant weak transition form factors are obtained by using the covariant light-front quark model, in which, the main inputs, i.e., the meson wave functions of $B_{c}$ and $D_{s}^{*}$, are adopted as the numerical wave functions from the solution of the Schr\"{o}dinger equation with the modified Godfrey-Isgur model. With the obtained form factors, we further investigate the relevant branching fractions and their ratios, and some angular observables, i.e., the forward-backward asymmetry $A_{FB}$, the polarization fractions $F_{L(T)}$, and the $CP$-averaged angular coefficients $S_{i}$ and the $CP$ asymmetry coefficients $A_{i}$. We also present our results of the clean angular observables $P_{1,2,3}$ and $P^{\prime}_{4,5,6,8}$, which can reduce the uncertainties from the form factors. Our results show that the corresponding branching fractions of the electron or muon channels can reach up to $10^{-8}$. With more data being accumulated in the LHCb experiment, our results are helpful for exploring this process, and deepen our understanding of the physics around the $b\to{s}\ell^{+}\ell^{-}$ process., Comment: 25 pages, 8 tables and 9 figures

In this work, we investigate the spectroscopy of higher $B_c$ mesons, with a special focus on the consideration of the unquenched effects. To account for such effects, we employ the modified Godfrey-Isgur model and introduce a screening potential. The resulting mass spectrum of the concerned higher $B_c$ states is then presented, showing significant deviations after considering the unquenched effects. This emphasizes the importance of considering the unquenched effects when studying of the higher $B_c$ mesons. Furthermore, we determine the corresponding spatial wave functions of these $B_c$ mesons, which have practical applications in subsequent studies of their decays. These decays include two-body Okuba-Zweig-Iizuka allowed strong decays, dipion transitions between $B_c$ mesons, radiative decays, and some typical weak decays. With the ongoing high-luminosity upgrade of the Large Hadron Collider, we expect the discovery of additional $B_c$ states in the near future. The knowledge gained from the mass spectrum and the different decay modes will undoubtedly provide valuable insights for future experimental explorations of these higher $B_c$ mesons., Comment: 30 pages, 7 figures and 17 tables

We calculate the form factors of the $\Lambda_b\to\Lambda_c(2625)$ and $\Xi_b\to\Xi_c(2815)$ transitions, and additionally evaluate the corresponding semileptonic decays and the color-allowed two-body nonleptonic decays. In order to obtain the concerned form factors, we use the three-body light-front quark model with the support from baryon spectroscopy. In this work, as important physical inputs, the spatial wave functions of concerned baryons are obtained by the Gaussian expansion method with a semirelativistic potential model. For the semileptonic processes, the branching ratios of the electron and muon channels can reach up to the order of magnitude of $1\%$, where our result $\mathcal{B}(\Lambda_b^0\to\Lambda_c^+(2625)\mu^-\nu_{\mu})=(1.641\pm0.113)\%$ is consistent with the current experimental data. As for the nonleptonic processes, the decays to $\pi^-$, $\rho^-$, and $D_s^{(*)-}$ final states have considerable widths. These discussed decay modes could be accessible at the LHCb experiment., Comment: 18 pages, 7 tables and 6 figures. More discussions added. Accepted by Phys. Rev. D

We calculate the weak transition form factors of the $\Lambda_b\to\Lambda(1520)$ transition, and further calculate the angular distributions of the rare decays $\Lambda_b\to\Lambda(1520)(\to N\bar{K})\ell^{+}\ell^{-}$ ($N\bar{K}=\{pK^-,n\bar{K}^0\}$) with unpolarized $\Lambda_b$ and massive leptons. The form factors are calculated by the three-body light-front quark model with the support of numerical wave functions of $\Lambda_b$ and $\Lambda(1520)$ from solving the semirelativistic potential model associated with the Gaussian expansion method. By fitting the mass spectrum of the observed single bottom and charmed baryons, the parameters of the potential model are fixed, so this strategy can avoid the uncertainties arising from the choice of a simple harmonic oscillator wave function of the baryons. With more data accumulated in the LHCb experiment, our result can help for exploring the $\Lambda_b\to\Lambda(1520)\ell^+\ell^-$ decay and deepen our understanding on the $b\to s\ell^+\ell^-$ processes., Comment: 21 pages, 9 figures. Accepted by Phys. Rev. D

In this work, we investigate the $\Upsilon(10753)\to\Upsilon(1^3D_J)\eta$ ($J=1,2,3$) processes, where the $\Upsilon(10753)$ is assigned as a conventional bottomonium under the $4S$-$3D$ mixing scheme. Our result shows that the concerned processes have considerable branching ratios, {\it i.e.}, branching ratios $\mathcal{B}[\Upsilon(10753)\to\Upsilon(1^3D_{1})\eta]$ and $\mathcal{B}[\Upsilon(10753)\to\Upsilon(1^3D_{2})\eta]$ can reach up to the order of magnitude of $10^{-4}-10^{-3}$, while $\mathcal{B}[\Upsilon(10753)\to\Upsilon(1^3D_{3})\eta]$ is around $10^{-6}-10^{-5}$. With the running of Belle II, it is a good opportunity for finding out the concerned hidden-bottom hadronic decays., Comment: 7 pages, 2 figures and 1 table. arXiv admin note: text overlap with arXiv:2106.14123, arXiv:2201.12715

In this work, we investigate the $\Upsilon(10753)\to\Upsilon(nS)\pi^+\pi^-$ ($n=1,2,3$) processes by considering the hadronic loop mechanism, where $\Upsilon(10753)$ is assigned to a conventional bottomonium in the $4S$-$3D$ mixing scheme. Our results of the concerned processes own considerable branching ratios, which can reach up to the order of magnitude of $10^{-4}-10^{-3}$. We should indicate that the measured $\Gamma_{e^+e^-}\times\mathcal{B}[\Upsilon(10753)\to\Upsilon(nS)\pi^+\pi^-]$ values given by Belle can be reproduced well. This fact supports the former bottomonium assignment to the $\Upsilon(10753)$ in the $4S$-$3D$ mixing scheme. Obviously, it is a good opportunity for the ongoing Belle II experiment if the predicted result in this work can be tested further., Comment: 7 pages, 4 figures and 1 table. arXiv admin note: text overlap with arXiv:2106.14123

In this work, we calculate the branching ratios of the color-allowed two-body nonleptonic decays of the bottom baryons, which include the $\Xi_b\to \Xi_c^{(*)}$ and $\Omega_b\to \Omega_c^{(*)}$ weak transitions by emitting a pseudoscalar meson ($\pi^{-}$, $K^{-}$, $D^{-}$, and $D_s^{-}$) or a vector meson ($\rho^{-}$, $K^{*-}$, $D^{*-}$, and $D_s^{*-}$). For achieving this aim, we adopt the three-body light-front quark model with the support of hadron spectroscopy, where the spatial wave functions of these heavy baryons involved in these weak decays are obtained by a semirelativistic potential model associated with the Gaussian expansion method. Our results show that these decays with the $\pi^-$, $\rho^-$, and $D_s^{(*)-}$-emitted mode have considerable widths, which could be accessible at the ongoing LHCb and Belle II experiments., Comment: 12 pages, 2 figures and 8 tables. Accepted by Phys. Rev. D

In this work, we propose the $4S$-$3D$ mixing scheme to assign the $\Upsilon(10753)$ into the conventional bottomonium family. Under this interpretation, we further study its hidden-bottom hadronic decays with a $\eta^{(\prime)}$ or $\omega$ emission, which include $\Upsilon(10753)\to\Upsilon(1S)\eta^{(\prime)}$, $\Upsilon(10753)\to h_{b}(1P)\eta$ and $\Upsilon(10753)\to\chi_{bJ}\omega$ ($J$=0,1,2) processes. Since the $\Upsilon(10753)$ is above the $B\bar{B}$ threshold, the coupled-channel effect cannot be ignored, thus, when calculating partial decay widths of these $\Upsilon(10753)$ hidden-bottom decays, we apply the hadronic loop mechanism. Our result shows that these discussed decay processes own considerable branching fractions with the order of magnitude of $10^{-4}\sim 10^{-3}$, which can be accessible at Belle II and other future experiments., Comment: 10 pages, 6 figures and 1 table. Accepted by Phys. Rev. D

In this work, the branching ratio $\mathcal{B}[B\to K\chi_{c0}(2P)]$ is extracted for the first time through the fit fractions in the newly measured $B\to KD\bar{D}$ process by LHCb. With the rescattering mechanism, this extracted branching ratio is reproduced well. Our study further enforces the role of the newly measured $B\to KD\bar{D}$ process to establish the $\chi_{c0}(2P)$ charmonium state, which is a crucial step when constructing charmonium family., Comment: 9 figures, 2 figures and 2 tables. Version for publication in Phys. Rev. D

The semileptonic decays of $\Lambda_{b}\to\Lambda_{c}^{(*)}\ell\nu_\ell$ and $\Lambda_{c}\to\Lambda^{(*)}\ell\nu_\ell$ are studied in the light-front quark model in this work. Instead of the quark-diquark approximation, we use the three-body wave functions obtained by baryon spectroscopy. The ground states $(1/2^{+})$, the $\lambda$-mode orbital excited states $(1/2^{-})$, and the first radial excited states $(1/2^{+})$ of $\Lambda_{(c)}^{(*)}$ are considered. The discussions are given for the form factors, partial widths, branching fractions, leptonic forward-backward asymmetries, hadron polarizations, lepton polarizations, and the lepton flavor universalities. Our results are useful for the inputs of heavy baryon decays and understanding the baryon structures, and helpful for experimental measurements., Comment: 17 pages, 9 tables and 6 figures