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H. Sundu

Publications and source records attributed to H. Sundu.

At least 55 records · Page 3Linked to original sources
arXiv2023

Investigation of $Λ(1405)$ as a molecular pentaquark state

$Λ(1405)$ is one of the interesting particles with its unclear structure and distinct properties. It has a light mass compared to its non-strange counterpart, despite the strange quark it carries. This situation puts the investigation of this resonance among the hot topics in hadron physics and collects attention to clarify its properties. In this study, we focus on the calculation of the mass and residue of the $Λ(1405)$ resonance within the framework of QCD sum rules. We assign a structure in the form of a molecular pentaquark composed from admixture of $K^-$ meson-proton and $\bar{K}^0$ meson-neutron. Using an interpolating current in this form, the masses and the current coupling constant are attained as $m=1406\pm 128~\mathrm{MeV}$ and $λ=(3.35\pm 0.35)\times10^{-5}~\mathrm{GeV}^6$ for $\slashed{q}$ and $m=1402\pm 141~\mathrm{MeV}$ and $λ=(4.08\pm 1.08)\times10^{-5}~\mathrm{GeV}^6$ for $I$ Lorentz structures entering the calculations, respectively. The obtained mass values agree well with the experimental data supporting the plausibility of the considered structure.

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arXiv2023

Hadronic molecules $η_c η_c$ and $χ_{c0}χ_{c0}$

The fully charmed hadronic scalar molecules $\mathcal{M}_1=η_c η_c$ and $\mathcal{M}_2=χ_{c0}χ_{c0}$ are studied in the context of the QCD sum rule method. The masses $m$, $\widetilde{m}$ and current couplings $f$, $ \widetilde{f}$ of these states are calculated using the two-point sum rule approach. The obtained results $m=(6264 \pm 50)~\mathrm{MeV}$ and $ \widetilde{m}=(6954 \pm 50)~\mathrm{MeV}$ are employed to determine their decay channels. It is demonstrated that the processes $\mathcal{M}_1\to J/ψJ/ψ$ and $\mathcal{M}_1\to η_{c}η_{c}$ are kinematically allowed decay modes of $\mathcal{M}_1$. The molecule $\mathcal{M}_2$ decays to $J/ψJ/ψ$, $J/ψψ^{\prime}$, $η_{c}η_{c}$, $η_{c}η_{c}(2S)$, $η_{c}χ_{c1}(1P)$, and $χ_{c0} χ_{c0}$ mesons. The partial widths all of these processes are evaluated by means of the three-point sum rule calculations, which are necessary to extract the strong couplings $g_i$ at vertices $\mathcal{M}_1J/ψJ/ψ$, $\mathcal{M }_1η_{c}η_{c}$, and others. Our estimates for the full widths of the molecules $Γ_{\mathcal{M}_1}=(320 \pm 72)~\mathrm{MeV}$ and $Γ_{ \mathcal{M}_2}=(138 \pm 18)~\mathrm{MeV}$, as well as their masses are compared with parameters of the $X$ resonances discovered by the LHCb-ATLAS-CMS Collaborations in the di-$J/ψ$ and $J/ψψ^{\prime}$ invariant mass distributions. We argue that the molecule $\mathcal{M}_1$ can be considered as a real candidate to the resonance $X(6200)$. The structure $ \mathcal{M}_2$ may be interpreted as $X(6900)$ or one of its components in combination with a scalar tetraquark.

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arXiv2023

Fully charmed resonance $X(6900)$ and its beauty counterpart

The fully heavy scalar tetraquarks $T_{\mathrm{4Q}}=QQ\overline{Q}\overline{Q }$, ($Q=c, b$) are explored in the context of QCD sum rule method. We model $ T_{\mathrm{4Q}}$ as diquark-antidiquark systems composed of pseudoscalar constituents, and calculate their masses $m^{(\prime)}$ and couplings $ f^{(\prime)}$ within the two-point sum rule approach. Our results $m=(6928 \pm 50)~\mathrm{MeV}$ and $m^{\prime}=(18858 \pm 50)~\mathrm{MeV}$ for masses of the tetraquarks $T_{\mathrm{4c}}$ and $T_{\mathrm{4b}}$ prove that they can decay to hidden-flavor heavy mesons. The full width $Γ_{ \mathrm{4c}}$ of the $T_{\mathrm{4c}}$ is evaluated by taking into account the decay channels $T_{\mathrm{4c}} \to J/ψJ/ψ$, $J/ψψ^{\prime}$, $η_{c}η_{c}$, $η_{c}η_{c}(2S)$, $η_{c}χ_{c1}(1P)$, and $χ_{c0}χ_{c0}$. The partial widths of these processes depend on strong couplings $g_{i}$ at vertices $T_{\mathrm{4c} }J/ψJ/ψ$, $T_{\mathrm{4c}}J/ψψ^{\prime} $ etc., which are computed using the QCD three-point sum rule method. The decay $T_{\mathrm{4b} } \to η_{b}η_{b}$ is used to find the width $Γ_{\mathrm{4b}}$ of the $T_{\mathrm{4b}}$. The predictions for $m$ and $Γ_{\mathrm{4c} }=(128 \pm 22)~\mathrm{MeV}$ are compared with parameters of the fully charmed resonances reported by the LHCb, ATLAS, and CMS Collaborations. Based on this analysis, we interpret the tetraquark $T_{\mathrm{4c}}$ as a candidate to the resonance $X(6900)$. The mass $m^{\prime} $ and width $ Γ_{\mathrm{4b}}=(94 \pm 28)~\mathrm{MeV}$ of the exotic meson $T_{ \mathrm{4b}}$ can be used in future experimental investigations of these

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arXiv2023

Investigation of the strange pentaquark candidate $P_{ψs}^Λ(4338){}^0$ recently observed by LHCb

The recently observed strange pentaquark candidate, $P_{ψs}^Λ(4338){}^0$, is investigated to provide information about its nature and substructure. To this end, its mass and width through the decay channels $P_{ψs}^Λ(4338){}^0 \rightarrow J/ψΛ$ and $P_{ψs}^Λ(4338){}^0 \rightarrow η_c Λ$ are calculated by applying two- and three-point QCD sum rules, respectively. The state is considered as a $Ξ_c\bar{D}$ meson-baryon molecular structure with spin-parity quantum numbers $J^P=\frac{1}{2}^-$. The obtained mass, $m_{P_{ψs}^Λ(4338){}^0}=4338\pm 130~\mathrm{MeV}$, and width, $Γ_{P_{ψs}^Λ(4338){}^0}= 10.40\pm 1.93~\mathrm{MeV}$, are consistent with the experimental data within the presented uncertainties. This allows us to assign a $Ξ_c\bar{D}$ molecular structure of $J^P=\frac{1}{2}^-$ for the $P_{ψs}^Λ(4338){}^0$ state.

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arXiv2023

Strange partners of the doubly charmed tetraquark $T^{+}_{cc}$

The spectroscopic parameters and widths of the axial-vector $T_{cc:s}^{ \mathrm{AV}}$ and scalar $T_{cc:s}^{\mathrm{S}}$, $\widetilde{T}_{cc:s}^{ \mathrm{S}}$ strange partners of the doubly charmed exotic meson $T_{cc}^{+}$ with the content $cc\overline{u}\overline{s}$, are calculated in the framework of the QCD sum rule method. We model $T_{cc:s}^{\mathrm{AV}}$ as the diquark-antidiquark state composed of axial-vector and scalar components, whereas scalar particles $T_{cc:s}^{\mathrm{S}}$ and $\widetilde{ T}_{cc:s}^{\mathrm{S}}$ are built of axial-vector and scalar diquarks, respectively. The masses and current couplings of these tetraquarks are calculated in the context of the two-point sum rule approach by taking into account the quark, gluon and mixed condensates up to dimension $10$. The full width of the state $T_{cc:s}^{\mathrm{AV}}$ is found from analysis of the processes $T_{cc:s}^{\mathrm{AV}} \to D^{0}D_{s}^{\ast +}$ and $ T_{cc:s}^{\mathrm{AV}} \to D^{\ast}(2007)^{0}D_{s}^{+}$. Decays to $ D^{0}D_{s}^{+}$, $D^{\ast}(2007)^{0}D_{s}^{\ast+}$ and $D^{0}D_{s}^{+}$ mesons are utilized in the case of the scalar tetraquarks $T_{cc:s}^{\mathrm{ S}}$ and $\widetilde{T}_{cc:s}^{\mathrm{S}}$, respectively. The partial widths of the aforementioned decays are determined via the strong couplings $ g_1$, $g_2 $, $G_1$, $G_2$ and $\widetilde{G}$, which describe the strong interactions of the particles at the relevant tetraquark-meson-meson vertices. These couplings are computed using the QCD three-point sum rule method, most appropriate for the strong decays under study. ....

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arXiv2023

Near-threshold structures in the $D_{s}^{+}D_{s}^{-}$ mass distribution of the decay $B^{+}\rightarrow D_{s}^{+}D_{s}^{-}K^{+}$

Two near-threshold peaking structures with spin-parities $J^{\mathrm{PC} }=0^{++}$ were recently discovered by the LHCb Collaboration in the $ D_{s}^{+}D_{s}^{-}$ invariant mass distribution of the decay $ B^{+}\rightarrow D_{s}^{+}D_{s}^{-}K^{+}$. The first of them is the resonance $X(3960)$, whereas the second one, $X_0(4140)$, is a structure with the mass around $4140~\mathrm{MeV}$. To explore their natures and model them, we study the hadronic molecule $\mathcal{M}=D_s^{+}D_s^{-}$ and calculate its mass, current coupling, and width. The mass and current coupling of the molecule are extracted from the QCD two-point sum rule analyses by taking into account vacuum condensates up to dimension $10$. To evaluate its full width, we consider the processes $\mathcal{M} \to D_{s}^{+}D_{s}^{-}$, $\mathcal{M} \toη_{c}η^{(\prime)}$, and $\mathcal{ M} \to J/ψϕ$. Partial widths of these decays are determined by the strong couplings $g_i, \ i=1,2,3,4 $ at vertices $\mathcal{M} D_{s}^{+}D_{s}^{-}$, $\mathcal{M}η_{c} η^{(\prime)}$, and $\mathcal{M} J/ψϕ$. They are computed by means of the three-point sum rule method. Predictions for the mass $m=(4117 \pm 85)~\mathrm{MeV}$ and width $Γ_{ \mathcal{M}}=(62 \pm 12)~\mathrm{MeV}$ of the molecule $\mathcal{M}$ are compared with the corresponding LHCb data, and also with our results for the diquark-antidiquark state $X=[cs][\overline{c}\overline{s}]$. We argue that the structure $X_0(4140)$ may be interpreted as the hadronic molecule $ D_s^{+}D_s^{-}$, whereas the resonance $X(3960)$ can be identified with the tetraquark $X$.

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arXiv2023

Modeling the resonance $T_{cs0}^{a}(2900)^{++}$ as a hadronic molecule $D^{\ast +}K^{\ast +}$

The doubly charged scalar resonance $T_{cs0}^{a}(2900)^{++}$ is studied in the context of the hadronic molecule model. We consider $ T_{cs0}^{a}(2900)^{++}$ as a molecule $M=D^{\ast +}K^{\ast +}$ composed of vector mesons, and calculate its mass, current coupling and full width. The spectroscopic parameters of $M$, i.e., its mass and current coupling, are found by means of the QCD two-point sum rule method by taking into account vacuum expectation values of quark, gluon and mixed operators up to dimension $10$. The width of the molecule $M$ is evaluated through the calculations of the partial widths of the decay channels $M \to D_{s}^{+}π^{+}$, $M \to D_{s}^{\ast +}ρ^{+}$, and $M \to D^{\ast +}K^{\ast +}$. Partial widths of these processes are determined by strong couplings $g_1$, $g_2$, and $g_3$ of particles at vertices $ MD_{s}^{+}π^{+} $, $MD_{s}^{\ast +}ρ^{+}$, and $M D^{\ast +}K^{\ast +}$ , respectively. We calculate the couplings $g_i$ by employing the QCD light-cone sum rule approach and technical tools of the soft-meson approximation. Predictions obtained for the mass $m=(2924 \pm 107)~\mathrm{ MeV}$ and width $Γ=(123 \pm 25)~\mathrm{MeV}$ of the hadronic molecule $ M$ allow us to consider it as a possible candidate of the resonance $ T_{cs0}^{a}(2900)^{++}$.

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arXiv2023

On the structures of new scalar resonances $T_{cs0}^{a}(2900)^{++}$ and $T_{cs0}^{a}(2900)^{0}$

We investigate properties of the new scalar resonances $ T_{cs0}^{a}(2900)^{++}$ and $T_{cs0}^{a}(2900)^{0}$, which were recently reported by the LHCb collaboration. These states were observed as resonant structures in $D_{s}^{+}π^{+}$ and $D_{s}^{+}π^{-}$ invariant mass distributions in $B^{+}$ meson decays. We argue that $T_{cs0}^{a}(2900)^{++} $ and $T_{cs0}^{a}(2900)^{0}$ may be modeled as molecules $\mathcal{M} ^{++}=D_{s}^{\ast+}ρ^{+}$ and $\mathcal{M}^{0}=D_{s}^{\ast+}ρ^{-} $ of conventional vector mesons, respectively. The mass $m$ and current coupling $ f $ of the molecule $\mathcal{M}^{++}$ are calculated using two-point sum rule method. The sum rule analysis is performed by taking into account vacuum condensates up to dimension $8$. The obtained result for the mass, $ m=(2917 \pm 135)~\mathrm{MeV}$, permits us to consider the molecule $ \mathcal{M}^{++}$ as one of possible models of the resonance $ T_{cs0}^{a}(2900)^{++}$. Because the second structure $T_{cs0}^{a}(2900)^{0}$ is isospin partner of the doubly charged state, it should have the mass close to $m$.

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arXiv2023

Axial-vector and pseudoscalar tetraquarks $[ud][\bar{c}\bar{s}]$

Spectroscopic parameters and widths of the fully open-flavor axial-vector and pseudoscalar tetraquarks $X_{\mathrm{AV}}$ and $X_{\mathrm{PS}}$ with content $[ud][\overline{c}\overline{s}]$ are calculated by means of the QCD sum rule methods. Masses and current couplings of $X_{\mathrm{AV}}$ and $X_{ \mathrm{PS}}$ are found using two-point sum rule computations performed by taking into account various vacuum condensates up to dimension $10$. The full width of the axial-vector state $X_{\mathrm{AV}}$ is evaluated by including into analysis $S$-wave decay modes $X_{\mathrm{AV}}\to D^{\ast }(2010)^{-}K^{+}$, $\overline{D}^{\ast }(2007)^{0}K^{0}$, $D^{-}K^{\ast }(892)^{+}$, and $\overline{D}^{0}K^{\ast }(892)^{0}$. In the case of $X_{ \mathrm{PS}}$, we consider $S$-wave decay $X_{\mathrm{PS}}\to \overline{D} _{0}^{\ast }(2300)^{0}K^{0}$, and $P$-wave processes $X_{\mathrm{PS}}\to D^{-}K^{\ast}(892)^{+}$ and $X_{\mathrm{PS}}\to \overline{D} ^{0}K^{\ast}(892)^{0}$. To determine partial widths of these decay modes, we employ the QCD light-cone sum rule method and soft-meson approximation, which are necessary to estimate strong couplings at tetraquark-meson-meson vertices $X_{\mathrm{AV}}D^{-}D^{\ast }(2010)^{-}K^{+} $, etc. Our predictions for the mass $m_{\mathrm{AV}}=(2800 \pm 75)~\mathrm{MeV}$ and width $Γ_{\mathrm{AV}}=(58 \pm 10)~\mathrm{MeV}$ of the tetraquark $X_{ \mathrm{AV}}$, as well as results $m_{\mathrm{PS}}=(3000 \pm 60)~\mathrm{MeV} $ and $Γ_{\mathrm{PS}}=(65 \pm 12)~\mathrm{MeV}$ for the same parameters of $X_{\mathrm{PS}}$ may be useful in future experimental studies of multiquark hadrons.

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arXiv2023

Resonance $X(3960)$ as a hidden charm-strange scalar tetraquark

We investigate features of the hidden charm-strange scalar tetraquark $c \overline{c}s\overline{s}$ by calculating its spectral parameters and width, and we compare the obtained results with the mass and width of the resonance $ X(3960)$ discovered recently in the LHCb experiment. We model the tetraquark as a diquark-antidiquark state $X=[cs][\overline{c}\overline{s}]$ with spin-parities $J^{\mathrm{PC}}=0^{++}$. The mass and current coupling of $X$ are calculated using the QCD two-point sum rules by taking into account various vacuum condensates up to dimension $10$. The width of the tetraquark $X$ is estimated via the decay channels $X \to D_{s}^{+}D_{s}^{-}$ and $X \to η_{c} η^{(\prime)}$. The partial widths of these processes are expressed in terms of couplings $G$, $g_1$ and $g_2$ which describe the strong interactions of particles at the vertices $XD_{s}^{+}D_{s}^{-}$, $ Xη_{c}η^{\prime}$ and $Xη_{c}η$, respectively. Numerical values of $G$, $g_1$ and $g_2$ are evaluated by employing the three-point sum rule method. Comparing the results $m=(3976 \pm 85)~\mathrm{MeV}$ and $Γ_{ \mathrm{X}}=(42.2 \pm 12.0)~\mathrm{MeV}$ obtained for parameters of the tetraquark $X$ and experimental data of the LHCb Collaboration, we conclude that the resonance $X(3960)$ can be considered as a candidate to a scalar diquark-antidiquark state.

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arXiv2023

Investigation of a candidate spin-$\frac{1}{2}$ hidden-charm triple strange pentaquark state $P_{csss}$

A candidate triple strange pentaquark state, $P_{csss}$, is investigated through its strong decay channel $P_{csss} \rightarrow Ω^-J/ψ$. To calculate the relevant strong coupling constants, two possible interpolating currents with spin-parity $J^P=\frac{1}{2}^{-}$ are used. Though the chosen currents for the state under consideration have spin-parity quantum numbers $J^P=\frac{1}{2}^{-}$, they couple to both the positive and negative parity states simultaneously and the corresponding decay widths are obtained for both parities. These widths are obtained as $Γ(P_{csss} \rightarrow J/ψΩ^-)=201.4\pm 82.5~\mathrm{MeV}$ for the negative and $Γ(\widetilde{P}_{csss} \rightarrow J/ψΩ^-)=316.4\pm 107.8~\mathrm{MeV}$ for the positive parity state when the first current is used. For the second current, we obtain $Γ(P_{csss} \rightarrow J/ψΩ^-)=252.5\pm 116.7~\mathrm{MeV}$ for the negative and $Γ(\widetilde{P}_{csss} \rightarrow J/ψΩ^-)=361.1\pm 98.4~\mathrm{MeV}$ for the positive parity state. These results may provide insights into future experimental observations of such candidate states and help to distinguish and fix their properties.

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arXiv2022

Heavy-light hybrid mesons with different spin-parities

The spectroscopic parameters of the heavy-light hybrid mesons with different spin-parities and different quark contents are investigated in the framework of the QCD sum rule method. The mass and current coupling of these states are calculated by taking into account the quark, gluon and mixed vacuum condensates up to dimension 10. The obtained results are compared with the existing QCD Laplace sum rule predictions. The results of mass and current coupling for all the considered channels are obtained to be stable and reliable. Our results can be useful for future experimental searches as well as theoretical studies of different parameters related to the hybrid mesons and their decays and interactions with other particles.

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arXiv2022

Interpretation of the $Λ_c(2910)^+$ baryon newly seen by Belle Collaboration and its possible bottom partner

The developments in the experimental facilities and analyses techniques have recently lead to the observation of many hadronic states ranging from excitations of conventional hadrons to various exotic states. The baryons with single heavy quark are among these states providing an attractive field of research to get a better understanding of the nonperturbative nature of the strong interaction. Recently, the Belle Collaboration announced observation of the state $Λ_c(2910)^+$ with a mass $2913.8\pm5.6\pm3.8~\mathrm{MeV}/c^2$ and width $51.8\pm20.0\pm18.8~\mathrm{MeV}$. In the present study, by the mass analyses of different excitations at $Λ_c$ channel and their comparison with existing experimental information, we find that the spin-parity of this newly found excited state is $ J^P= \frac{1}{2}^-$ and it is a $ 2P $ state denoting by $Λ_c(\frac{1}{2}^-,2P)$. We predict its current coupling as well, which can be served as one of the main input parameters to investigate different decays and interactions of this particle. We also determine the mass and current coupling of $Λ_b(\frac{1}{2}^-,2P)$ as possible bottom counterpart of the new $Λ_c(2910)^+$ state, which may be in agenda of different experiments in near future.

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arXiv2022

Is the resonance $X_0(2900)$ a ground-state or radially excited scalar tetraquark $[ud][\overline{c}\overline{s}]$?

We investigate properties of the ground-state and first radially excited four-quark mesons $X_0$ and $X_0^{\prime}$ with a diquark-antidiquark structure $[ud][\overline{c}\overline{s}]$ and spin-parities $J^{\mathrm{P} }=0^{+}$. Our aim is to reveal whether or not one of these states can be identified with the resonance $X_0(2900)$, recently discovered by the LHCb collaboration. We model $X_0$ and $X_0^{\prime}$ as tetraquarks composed of either axial-vector or scalar diquark and antidiquark pairs. Their spectroscopic parameters are computed by employing the QCD two-point sum rule method and including into analysis vacuum condensates up to dimension $ 15$. For an axial-axial structure of $X_0^{(\prime)}$, we find partial widths of the decays $X_0^{(\prime)} \to D^{-}K^{+}$ and $X_0^{(\prime)} \to D^{0}K^{0}$, and estimate full widths of the states $X_0^{(\prime)}$. To this end, we calculate the strong couplings at the vertices $ X_0^{(\prime)}DK $ in the framework of the light-cone sum rule method. We use also technical approaches of the soft-meson approximation necessary to analyze tetraquark-meson-meson vertices. Obtained results $m=(2545 \pm 160)~ \mathrm{MeV}$ and $m^{\prime}=(3320 \pm 120)~\mathrm{MeV}$ [$m_{\mathrm{S} }=(2663 \pm 110)~\mathrm{MeV}$ and $m_{\mathrm{S}}^{\prime}=(3325 \pm 85)~ \mathrm{MeV}$ for a scalar-scalar current] for the masses of the particles $ X_0$ and $X_0^{\prime}$, as well as estimates for their full widths $ Γ_{0}=(140 \pm 29)~\mathrm{MeV}$ and $Γ_{0}^{\prime}=(110 \pm 25)~ \mathrm{MeV}$ allow us to interpret none of them as the resonance $X_0(2900)$ . At the same time, these predictions provide important information about ground-state and radially excited diquark-antidiquark structures $X_0$ and $ X_0^{\prime}$, which should be objects of future experimental and theoretical studies.

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arXiv2022

Resonance $X(4630)$

We investigate the structure $X(4630)$ discovered by the LHCb collaboration in the process $B^{+}\rightarrow J/ψϕK^{+}$ as a resonance in the $ J/ψϕ$ mass distribution. We explore this resonance as a diquark-antidiquark state $X=[cs][\overline{c}\overline{s}]$ with spin-parities $J^{\mathrm{PC}}=1^{-+}$. Its mass and current coupling are calculated using the QCD two-point sum rule method by taking into account vacuum condensates up to dimension $10$. We also study decays of this tetraquark to mesons $J/ψϕ$, $η_{c}η^{(\prime )}$, and $χ_{c1}η^{(\prime )}$, and compute partial widths of these channels. To this end, we employ the light-cone sum rule approach and technical methods of soft-meson approximation to extract strong coupling at relevant tetraquark-meson-meson vertices. Our predictions for the mass $m=(4632\pm 60)~\mathrm{MeV}$ and width $Γ=(159\pm 31)~\mathrm{MeV}$ of $X$ are in a very nice agreement with recent measurements of the LHCb collaboration. These results allow us to interpret the resonance $X(4630)$ as the tetraquark $X$ with spin-parities $J^{\mathrm{PC}}=1^{-+}$.

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arXiv2022

Investigation of hidden-charm double strange pentaquark candidate $P_{css}$ via its mass and strong decays

This work presents an analysis of a hidden charmed pentaquark candidate state with double strange quark in its quark content. The investigation is performed in two parts, which provide the mass prediction of the considered state and its partial decay widths for the $P_{css}\rightarrow Ξ^0 J/ψ$ and $P_{css}\rightarrow Ξ_c^+ D_s^-$ channels. For the analyses, two-point and three-point QCD sum rule methods are applied to get the mass and the widths, respectively. The mass for this candidate state is obtained as $m_{P_{css}}=4600 \pm 155$ MeV with corresponding current coupling constant $λ_{P_{css}}=(0.81 \pm 0.21)\times 10^{-3}$ GeV$^6$. These results are used in the analysis of the partial widths of this state for the decays $P_{css}\rightarrow Ξ^0 J/ψ$ and $P_{css}\rightarrow Ξ_c^+ D_s^-$. From these decays, the total width is obtained as $Γ= 12.29\pm 2.94 $ MeV. These results may shed light on the future experimental searches in which such types of states are probed and may provide information to discriminate between such possible observations.

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arXiv2022

Hadronic molecule model for the doubly charmed state $T^{+}_{cc}$

The mass, current coupling, and width of the doubly charmed four-quark meson $T_{cc}^{+}$ are explored by treating it as a hadronic molecule $ M_{cc}^{+}\equiv D^{0}D^{\ast +}$. The mass and current coupling of this molecule are calculated using the QCD two-point sum rule method by including into analysis contributions of various vacuum condensates up to dimension $ 10 $. The prediction for the mass $m=(4060\pm 130)~\mathrm{MeV}$ exceeds the two-meson $D^{0}D^{\ast +}$ threshold $3875.1~\mathrm{MeV}$, which makes decay of the molecule $M_{cc}^{+}$ to a pair of conventional mesons $ D^{0}D^{\ast +}$ kinematically allowed process. The strong coupling $G $ of particles at the vertex $M_{cc}^{+}D^{0}D^{\ast +}$ is found by applying the QCD three-point sum rule approach, and used to evaluate the width of the decay $M_{cc}^{+} \to D^{0}D^{\ast +}$. Obtained result for the width $ Γ=(3.8\pm 1.7)~\mathrm{MeV}$ demonstrates that $M_{cc}^{+}$ is wider than the resonance $T_{cc}^{+}$.

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arXiv2022

Impact of a thermal medium on newly observed $Z_{cs}(3985)$ resonance and its $ b $-partner

Motivated by the very recent discovery of the strange hidden-charm exotic state $Z_{cs}(3985)$ by the BESIII Collaboration, we study possible interpretation of this exotic state both at $ T= 0 $ and $ T\neq 0 $. We analytically compute the mass and meson-current coupling constant of this resonance with spin-parity $ J^{PC} = 1^{+-}$ at finite temperature approximation up to sixth order of the thermal operator dimension including non-perturbative contributions. Extracting thermal mass and meson-current coupling constant sum rules, the modifications on properties of $Z_{cs}(3985)$ state in hot medium is determined. As a by product, the hadronic parameters of the bottom partner of $Z_{cs}(3985)$ is estimated as well. Moreover the search of temperature effects on the hadronic parameters of hidden-charm meson $Z_{cs}(3985)$ and the bottom partner make us understand the phase transitions, chiral symmetry breaking and the properties of hot-dense matter in QCD.

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