Using the phenomenological relativistic harmonic model （RHM） for quarks, we have obtained the masses of S wave charmonium states. The full Hamiltonian used in the investigation has Lorentz scalar plus vector confine...Using the phenomenological relativistic harmonic model （RHM） for quarks, we have obtained the masses of S wave charmonium states. The full Hamiltonian used in the investigation has Lorentz scalar plus vector confinement potential, along with the confined one gluon exchange potential （COGEP）. A good agreement with the experimental masses for the ground state and the radially excited states is obtained for both the triplet and singlet S wave mesons. The calculated charge radii, meson decay constants, leptonic decay width, two photon decay width, and the radiative M1 decay width are in good agreement with the experimental results.展开更多
In this article,we study the vector meson transitions among the charmonium and bottomonium states with the heavy quark effective theory in a systematic way,and make predictions for the ratios among the vector meson de...In this article,we study the vector meson transitions among the charmonium and bottomonium states with the heavy quark effective theory in a systematic way,and make predictions for the ratios among the vector meson decay widths of a special multiplet to another multiplet.The predictions can be confronted with the experimental data in the future.展开更多
The unquenched quark model for the light quarkonium and charmonium states is explored in this study.The quark-pair creation operator in the^(3)P_(0) model,which combines the two-quark and four-quark components,is modi...The unquenched quark model for the light quarkonium and charmonium states is explored in this study.The quark-pair creation operator in the^(3)P_(0) model,which combines the two-quark and four-quark components,is modified by considering the effects of the created quark pair's energy.Furthermore,the separation between the created quark pair and valence quark pair is modified.All the wave functions,including those for the mesons and the relative motion between two mesons,are obtained by solving the corresponding Schrodinger equation using the Gaussian expansion method.The aim of this study is to find a new set of parameters that can accurately describe the mass spectrum of low-lying light quarkonium and charmonium states.Moreover,certain exotic states,such as X(3872),can be described well in the unquenched quark model.展开更多
We have investigated the internal structure of the open-and hidden-charmed(DD^(*)/DD^(*))molecules in the unified framework.We first fit the experimental lineshape of the Tt state and extract the DD^(*)interaction,fro...We have investigated the internal structure of the open-and hidden-charmed(DD^(*)/DD^(*))molecules in the unified framework.We first fit the experimental lineshape of the Tt state and extract the DD^(*)interaction,from which the T is assumed to arise solely.Then we obtain the DD^(*)interaction by charge conjugation.Our results show that the DD*interaction is attractive but insufficient to form X(3872)as a bound state.Instead,its formation requires the crucial involvement of the coupled channel effect between the DD^(*)and cc components,although the cc accounts for approximately 1%only.Besides X(3872),we have obtained a higher-energy state around 3957.9 MeV with a width of 16.7 MeV,which may be a potential candidate for the X(3940).In J^(PC)=1^(+-)sector,we have found two states related to the iso-scalar X(3872)and h_(c)(2P),respectively.Our combined study provides valuable insights into the nature of these DD^(+)/DD^(+)exotic states.展开更多
Motivated by the large rates of B→(χc0,χc2,hc)K decays observed by the BABAR and Belle collaborations,we investigate the nonfactorizable contributions to these factorization-forbidden decays,which can occur through...Motivated by the large rates of B→(χc0,χc2,hc)K decays observed by the BABAR and Belle collaborations,we investigate the nonfactorizable contributions to these factorization-forbidden decays,which can occur through a gluon exchange between the cc system and the spectator quark.Our numerical results demonstrate that the spectator contributions are capable of producing a large branching ratio consistent with the experiments.As a by-product,we also study the Cabibbo-suppressed decays,such as B→(χc0,χc2,hc)πand the U-spin-related Bs decay,which have so far received less theoretical and experimental attention.The calculated branching ratios reach the order of 10−6,which is within the scope of the Belle-Ⅱ and LHCb experiments.Further,the CP-asymmetry parameters are also calculated for these decays.The obtained results are compared with the available experimental data and numbers from other predictions.We also investigate the sources of theoretical uncertainties in our calculation.展开更多
We investigate the in-medium masses of open charm mesons(D(D^(0),D^(+)),■(■^(0),D^(-)),D_(s)(D_(s)^(+),D_(s)^(-)))and charmonium states(J/ψ,ψ(3686),ψ(3770),χ_(c0),χ_(c2)) in strongly magnetized isospin asymmetr...We investigate the in-medium masses of open charm mesons(D(D^(0),D^(+)),■(■^(0),D^(-)),D_(s)(D_(s)^(+),D_(s)^(-)))and charmonium states(J/ψ,ψ(3686),ψ(3770),χ_(c0),χ_(c2)) in strongly magnetized isospin asymmetric strange hadronic matter using a chiral effective model.In the presence of a magnetic field,the number and scalar densities of charged baryons have contributions from Landau energy levels.The mass modifications of open charm mesons result from their interactions with nucleons,hyperons,and the scalar fields(the non-strange field σ,strange field C and isovector field δ) in the presence of a magnetic field.The mass modifications of the charmonium states result from the modification of gluon condensates in a medium simulated by the variation in the dilaton field(χ) in the chiral effective model.The effects of finite quark masses are also incorporated in the trace of the energy-momentum tensor in quantum chromodynamics to investigate the mass shifts of charmonium states.The in-medium masses of open charm mesons and charmonia are observed to decrease with an increase in baryon density.The charged D^(+),D^(-),Z_(s)^(+),and D_(s)^(-)mesons have additional positive mass shifts due to Landau quantization in the presence of a magnetic field.The effects of the strangeness fraction are observed to be more dominant for ■ mesons compared with D mesons.The mass shifts of charmonia are observed to be larger in hyperonic media compared with nuclear media when the effect of the finite quark mass term is neglected.These medium mass modifications can have observable consequences on the production of the open charm mesons and charmonia in high-energy asymmetric heavy-ion collision experiments.展开更多
We discuss recent measurements of exclusive e^＋e^- cross sections for charmed hadron final states near threshold performed by Belle and BABAR. The results are based on a study of events with initial-stateradiation ph...We discuss recent measurements of exclusive e^＋e^- cross sections for charmed hadron final states near threshold performed by Belle and BABAR. The results are based on a study of events with initial-stateradiation photons in a large data sample collected with the Belle and BABAR detectors at the T（4S） resonance and nearby continuum.展开更多
Based on the prediction of a D^∗D^¯∗molecular state Zc(4000)with isospin I=1 in the coupled channel approach,we suggest the search for this state in the reaction B−→J/ψρ0K−.By considering the final state inter...Based on the prediction of a D^∗D^¯∗molecular state Zc(4000)with isospin I=1 in the coupled channel approach,we suggest the search for this state in the reaction B−→J/ψρ0K−.By considering the final state interactions of J/ψρand D^∗0D^¯∗0 and the contribution from the K1(1270)resonance,we observed that the J/ψρmass distribution shows a peak around 4000 MeV,which might be associated with the D^∗D^¯∗molecular state Zc(4000).The search for Zc(4000)in the reaction B−→J/ψρ^0K−is critical for understanding the internal structures of exotic hadrons.Our predictions can be tested by the Belle II and LHCb in future studies.展开更多
基金the BRNS for funding the project(Sanction No.2010/37P/18/BRNS)
文摘Using the phenomenological relativistic harmonic model （RHM） for quarks, we have obtained the masses of S wave charmonium states. The full Hamiltonian used in the investigation has Lorentz scalar plus vector confinement potential, along with the confined one gluon exchange potential （COGEP）. A good agreement with the experimental masses for the ground state and the radially excited states is obtained for both the triplet and singlet S wave mesons. The calculated charge radii, meson decay constants, leptonic decay width, two photon decay width, and the radiative M1 decay width are in good agreement with the experimental results.
基金Supported by National Natural Science Foundation of China under Grant No. 11075053the Fundamental Research Funds for the Central Universities
文摘In this article,we study the vector meson transitions among the charmonium and bottomonium states with the heavy quark effective theory in a systematic way,and make predictions for the ratios among the vector meson decay widths of a special multiplet to another multiplet.The predictions can be confronted with the experimental data in the future.
基金Supported by the National Natural Science Foundation of China(12205125,11847145,12205249,11865019)the Natural Science Foundation of Jiangsu Province,China(BK20221166)。
文摘The unquenched quark model for the light quarkonium and charmonium states is explored in this study.The quark-pair creation operator in the^(3)P_(0) model,which combines the two-quark and four-quark components,is modified by considering the effects of the created quark pair's energy.Furthermore,the separation between the created quark pair and valence quark pair is modified.All the wave functions,including those for the mesons and the relative motion between two mesons,are obtained by solving the corresponding Schrodinger equation using the Gaussian expansion method.The aim of this study is to find a new set of parameters that can accurately describe the mass spectrum of low-lying light quarkonium and charmonium states.Moreover,certain exotic states,such as X(3872),can be described well in the unquenched quark model.
基金supported by the KAKENHI(19H05159,20K03959,and 21H00132(M.O.),and 23K03427(M.O.and G.J.W),24K17055(G.J.W))the National Natural Science Foundation of China(12275046(Z.Y.),12175239 and 12221005(J.J.W),11975033 and 12070131001(S.L.Z.))+2 种基金the Natural Science Foundation of Sichuan Province(2022NSFSC1795(Z.Y.))the National Key R&D Program of China(2020YFA0406400(J.J.W))the Chinese Academy of Sciences(YSBR-101(J.J.W)).
文摘We have investigated the internal structure of the open-and hidden-charmed(DD^(*)/DD^(*))molecules in the unified framework.We first fit the experimental lineshape of the Tt state and extract the DD^(*)interaction,from which the T is assumed to arise solely.Then we obtain the DD^(*)interaction by charge conjugation.Our results show that the DD*interaction is attractive but insufficient to form X(3872)as a bound state.Instead,its formation requires the crucial involvement of the coupled channel effect between the DD^(*)and cc components,although the cc accounts for approximately 1%only.Besides X(3872),we have obtained a higher-energy state around 3957.9 MeV with a width of 16.7 MeV,which may be a potential candidate for the X(3940).In J^(PC)=1^(+-)sector,we have found two states related to the iso-scalar X(3872)and h_(c)(2P),respectively.Our combined study provides valuable insights into the nature of these DD^(+)/DD^(+)exotic states.
基金Supported in part by the National Natural Science Foundation of China(11605060,11547020)the Natural Science Foundation of Hebei Province(A2019209449)Department of Education of Hebei Province(BJ2016041)。
文摘Motivated by the large rates of B→(χc0,χc2,hc)K decays observed by the BABAR and Belle collaborations,we investigate the nonfactorizable contributions to these factorization-forbidden decays,which can occur through a gluon exchange between the cc system and the spectator quark.Our numerical results demonstrate that the spectator contributions are capable of producing a large branching ratio consistent with the experiments.As a by-product,we also study the Cabibbo-suppressed decays,such as B→(χc0,χc2,hc)πand the U-spin-related Bs decay,which have so far received less theoretical and experimental attention.The calculated branching ratios reach the order of 10−6,which is within the scope of the Belle-Ⅱ and LHCb experiments.Further,the CP-asymmetry parameters are also calculated for these decays.The obtained results are compared with the available experimental data and numbers from other predictions.We also investigate the sources of theoretical uncertainties in our calculation.
基金This work was supported by the Spanish Ministerio de Ciencia e Innovación(MICINN)and the European Regional Development Fund(ERDF)under Contract PID2020-112777 GB-I00by the EU STRONG-2020 Project under the Program H2020-INFRAIA-2018–1 with Grant Agreement No.824093+4 种基金by Generalitat Valenciana under Contract PROMETEO/2020/023by the Chinese Academy of Sciences under Grant No.XDB34030000by the National Natural Science Foundation of China(NSFC)under Grants No.12125507,No.11835015,No.12047503,and No.11961141012by the NSFC and the Deutsche Forschungsgemeinschaft(DFG)through the funds provided to the Sino-German Collaborative Research Center TRR110“Symmetries and the Emergence of Structure in QCD”(NSFC Grant No.12070131001,DFG Project-ID 196253076)M.A.is supported by Generalitat Valenciana under Grant No.CIDEGENT/2020/002.
基金the support towards this work from the Department of Science and Technology,Government of India,via an INSPIRE fellowship (INSPIRE Code IF170745)financial support from Department of Science and Technology (DST),Government of India (CRG/2018/002226)。
文摘We investigate the in-medium masses of open charm mesons(D(D^(0),D^(+)),■(■^(0),D^(-)),D_(s)(D_(s)^(+),D_(s)^(-)))and charmonium states(J/ψ,ψ(3686),ψ(3770),χ_(c0),χ_(c2)) in strongly magnetized isospin asymmetric strange hadronic matter using a chiral effective model.In the presence of a magnetic field,the number and scalar densities of charged baryons have contributions from Landau energy levels.The mass modifications of open charm mesons result from their interactions with nucleons,hyperons,and the scalar fields(the non-strange field σ,strange field C and isovector field δ) in the presence of a magnetic field.The mass modifications of the charmonium states result from the modification of gluon condensates in a medium simulated by the variation in the dilaton field(χ) in the chiral effective model.The effects of finite quark masses are also incorporated in the trace of the energy-momentum tensor in quantum chromodynamics to investigate the mass shifts of charmonium states.The in-medium masses of open charm mesons and charmonia are observed to decrease with an increase in baryon density.The charged D^(+),D^(-),Z_(s)^(+),and D_(s)^(-)mesons have additional positive mass shifts due to Landau quantization in the presence of a magnetic field.The effects of the strangeness fraction are observed to be more dominant for ■ mesons compared with D mesons.The mass shifts of charmonia are observed to be larger in hyperonic media compared with nuclear media when the effect of the finite quark mass term is neglected.These medium mass modifications can have observable consequences on the production of the open charm mesons and charmonia in high-energy asymmetric heavy-ion collision experiments.
基金Supported by Ministry of Education and Science of the Russian Federation and Russian Federal Agency for Atomic Energy
文摘We discuss recent measurements of exclusive e^＋e^- cross sections for charmed hadron final states near threshold performed by Belle and BABAR. The results are based on a study of events with initial-stateradiation photons in a large data sample collected with the Belle and BABAR detectors at the T（4S） resonance and nearby continuum.
基金This work is partly Supported by the National Natural Science Foundation of China(11505158)the Key Research Projects of Henan Higher Education Institutions(20A140027)the Academic Improvement Project of Zhengzhou University。
文摘Based on the prediction of a D^∗D^¯∗molecular state Zc(4000)with isospin I=1 in the coupled channel approach,we suggest the search for this state in the reaction B−→J/ψρ0K−.By considering the final state interactions of J/ψρand D^∗0D^¯∗0 and the contribution from the K1(1270)resonance,we observed that the J/ψρmass distribution shows a peak around 4000 MeV,which might be associated with the D^∗D^¯∗molecular state Zc(4000).The search for Zc(4000)in the reaction B−→J/ψρ^0K−is critical for understanding the internal structures of exotic hadrons.Our predictions can be tested by the Belle II and LHCb in future studies.
