Some charmonium-like resonances such as X（3872） can be interpreted as possible D （＊） （＊） molecular states.Within the quark model,we study the structure of such molecular states and the similar B （＊） （＊...Some charmonium-like resonances such as X（3872） can be interpreted as possible D （＊） （＊） molecular states.Within the quark model,we study the structure of such molecular states and the similar B （＊） （＊） molecular states by taking into account the light meson exchange （π,η,ρ,ω and σ） between two light quarks from different mesons.展开更多
An effective potential in a meson-meson system is discussed based on the SU（3） chiral constituent quark model, and the analytic form of the potential is explicitly given. In addition, the effective potential is empl...An effective potential in a meson-meson system is discussed based on the SU（3） chiral constituent quark model, and the analytic form of the potential is explicitly given. In addition, the effective potential is employed to study the bound state problem of ωφ, which is related to the new resonance of f0（1810） observed in BES Ⅱ very recently.展开更多
We take the viewpoint that X（1576） is the tetraquark state which consists of a scalar diquark and an antiscalar-diquark in relative P-wave, and calculate its mass in the framework of the QCD sum rule approach. The n...We take the viewpoint that X（1576） is the tetraquark state which consists of a scalar diquark and an antiscalar-diquark in relative P-wave, and calculate its mass in the framework of the QCD sum rule approach. The numerical value of the mass mx= （1.66 =k 0.14） GeV is consistent with the experimental data. There might be some tetraquark components in the vector meson X（1576）.展开更多
We adopt the quark pair creation model to investigate the light meson emissions of several charmoniumlike states.The quark pair creation model is applied to four-body systems,and we calculate the pion/kaon emissions o...We adopt the quark pair creation model to investigate the light meson emissions of several charmoniumlike states.The quark pair creation model is applied to four-body systems,and we calculate the pion/kaon emissions of X(4700),Z_(c)(4430),Y(4230),Y(4360),Y(4390),and Y(4660)within compact tetraquark configurations.We find that the pion/kaon decay widths of X(4700)and Z_(c)(4430)the resonances Y(4230),Y(4360),Y(4390),and Y(4660)cay behaviors will provide useful information for future experimental searches and theoretical interpretations.展开更多
If we approximate light quarks as massless and apply the Schwinger confinement mechanism to light quarks,we will reach the conclusion that a light quark and its antiquark will be confined as a boson in the Abelian U(1...If we approximate light quarks as massless and apply the Schwinger confinement mechanism to light quarks,we will reach the conclusion that a light quark and its antiquark will be confined as a boson in the Abelian U(1)QED gauge interaction in(1+1)D,as in an open string.From the work of Coleman,Jackiw,and Susskind,we can infer further that the Schwinger confinement mechanism persists even for massive quarks in(1+1)D.Could such a QED-confined one-dimensional open string in(1+1)D be the idealization of a flux tube in the physical world in(3+1)D,similar to the case of QCD-confined open string?If so,the QED-confined bosons may show up as neutral QED mesons in the mass region of many tens of MeV[Phys.Rev.C 81,064903(2010)&J.High Energy Phys.2020(8),165(2020)].Is it ever possible that a quark and an antiquark be produced and interact in QED alone to form a confined QED meson?Is there any experimental evidence for the existence of a QED meson(or QED mesons)?The observations of the anomalous soft photons,the X17 particle,and the E38 particle suggest that they may bear the experimental evidence for the existence of such QED mesons.Further confirmation and investigations on the X17 and E38 particles will shed definitive light on the question of quark confinement in QED in(3+1)D.Implications of quark confinement in the QED interaction are discussed.展开更多
The recently observed X（3872） resonance, which is difficult to assign a conventional cc charmonium state in the quark model, may be interpreted as a molecular state. Such a molecular state is a hidden flavor four qu...The recently observed X（3872） resonance, which is difficult to assign a conventional cc charmonium state in the quark model, may be interpreted as a molecular state. Such a molecular state is a hidden flavor four quark state because of its charmonium-like quantum numbers. The s-channel one gluon exchange is an interaction which only acts in the hidden flavor multi-quark system. In this paper, we will study the X（3872） and other similiar hidden flavor molecular states in a quark model by taking into account the s-channel one gluon exchange interaction.展开更多
The surprising thing is that arising almost 50 years ago from the linear sigma model （LSM） with spontaneously broken chiral symmetry, the light scalar meson problem has become central in the nonperturbative quantum ...The surprising thing is that arising almost 50 years ago from the linear sigma model （LSM） with spontaneously broken chiral symmetry, the light scalar meson problem has become central in the nonperturbative quantum chromodynamics （QCD） for it has been made clear that LSM could be the low energy realization of QCD. First we review briefly signs of four-quark nature of light scalars. Then we show that the light scalars are produced in the two photon collisions via four-quark transitions in contrast to the classic P wave tensor qq mesons that are produced via two-quark transitions γγ→qq. Thus we get new evidence of the four-quark nature of these states.展开更多
文摘Some charmonium-like resonances such as X（3872） can be interpreted as possible D （＊） （＊） molecular states.Within the quark model,we study the structure of such molecular states and the similar B （＊） （＊） molecular states by taking into account the light meson exchange （π,η,ρ,ω and σ） between two light quarks from different mesons.
基金Supported by National Natrual Science Foundation (10775146, 10775148, 10975146, 11035006)Ministry of Science and Technology of China (2009CB825200)
文摘An effective potential in a meson-meson system is discussed based on the SU（3） chiral constituent quark model, and the analytic form of the potential is explicitly given. In addition, the effective potential is employed to study the bound state problem of ωφ, which is related to the new resonance of f0（1810） observed in BES Ⅱ very recently.
基金Supported by the National Natural Science Foundation under Grant No 10405009, and the Key Program Foundation of North China Electric Power University.
文摘We take the viewpoint that X（1576） is the tetraquark state which consists of a scalar diquark and an antiscalar-diquark in relative P-wave, and calculate its mass in the framework of the QCD sum rule approach. The numerical value of the mass mx= （1.66 =k 0.14） GeV is consistent with the experimental data. There might be some tetraquark components in the vector meson X（1576）.
基金Supported by the National Natural Science Foundation of China(11705056,12175037,11947224,11475192,11975245,U1832173)the Key Project of Hunan Provincial Education Department under(21A0039)+3 种基金the State Scholarship Fund of China Scholarship Council(22006725011)the Sino-German CRC 110“Symmetries and the Emergence of Structure in QCD”project by NSFC(12070131001)the Key Research Program of Frontier Sciences,CAS(Y7292610K1)the National Key Research and Development Program of China(2020YFA0406300)。
文摘We adopt the quark pair creation model to investigate the light meson emissions of several charmoniumlike states.The quark pair creation model is applied to four-body systems,and we calculate the pion/kaon emissions of X(4700),Z_(c)(4430),Y(4230),Y(4360),Y(4390),and Y(4660)within compact tetraquark configurations.We find that the pion/kaon decay widths of X(4700)and Z_(c)(4430)the resonances Y(4230),Y(4360),Y(4390),and Y(4660)cay behaviors will provide useful information for future experimental searches and theoretical interpretations.
基金supported in part by the Division of Nuclear Physics,U.S.Department of Energy under Contract No.DE-AC05-00OR22725 with UT-Battelle,LLC.
文摘If we approximate light quarks as massless and apply the Schwinger confinement mechanism to light quarks,we will reach the conclusion that a light quark and its antiquark will be confined as a boson in the Abelian U(1)QED gauge interaction in(1+1)D,as in an open string.From the work of Coleman,Jackiw,and Susskind,we can infer further that the Schwinger confinement mechanism persists even for massive quarks in(1+1)D.Could such a QED-confined one-dimensional open string in(1+1)D be the idealization of a flux tube in the physical world in(3+1)D,similar to the case of QCD-confined open string?If so,the QED-confined bosons may show up as neutral QED mesons in the mass region of many tens of MeV[Phys.Rev.C 81,064903(2010)&J.High Energy Phys.2020(8),165(2020)].Is it ever possible that a quark and an antiquark be produced and interact in QED alone to form a confined QED meson?Is there any experimental evidence for the existence of a QED meson(or QED mesons)?The observations of the anomalous soft photons,the X17 particle,and the E38 particle suggest that they may bear the experimental evidence for the existence of such QED mesons.Further confirmation and investigations on the X17 and E38 particles will shed definitive light on the question of quark confinement in QED in(3+1)D.Implications of quark confinement in the QED interaction are discussed.
文摘The recently observed X（3872） resonance, which is difficult to assign a conventional cc charmonium state in the quark model, may be interpreted as a molecular state. Such a molecular state is a hidden flavor four quark state because of its charmonium-like quantum numbers. The s-channel one gluon exchange is an interaction which only acts in the hidden flavor multi-quark system. In this paper, we will study the X（3872） and other similiar hidden flavor molecular states in a quark model by taking into account the s-channel one gluon exchange interaction.
基金Supported by RFFI Grant No.07-02-00093 from the Russian Foundation for Basic ResearchPresidential Grant No.NSh-1027.2008.2 for Leading Scientific Schools
文摘The surprising thing is that arising almost 50 years ago from the linear sigma model （LSM） with spontaneously broken chiral symmetry, the light scalar meson problem has become central in the nonperturbative quantum chromodynamics （QCD） for it has been made clear that LSM could be the low energy realization of QCD. First we review briefly signs of four-quark nature of light scalars. Then we show that the light scalars are produced in the two photon collisions via four-quark transitions in contrast to the classic P wave tensor qq mesons that are produced via two-quark transitions γγ→qq. Thus we get new evidence of the four-quark nature of these states.
