Purpose: The Harmonic Neutron Hypothesis, HNH, has demonstrated that many of the fundamental physical constants, including the quarks, are associated with partial harmonic fractional exponents, , of a fundamental freq...Purpose: The Harmonic Neutron Hypothesis, HNH, has demonstrated that many of the fundamental physical constants, including the quarks, are associated with partial harmonic fractional exponents, , of a fundamental frequency, v<sub>F</sub>. The model has shown that the properties of the quarks are based on a progression of prime number composites. They also fall on three separate power law lines related to integer factors of the Y-intercept, , of a fundamental electromagnetic line which is scaled by the Rydberg constant, R and Planck’s constant. The quark lines are scaled by the quantum number factors {1, 2, 3}, and their Y-intercepts are referred to as n<sub>bem</sub>. The goal is to present a new proto-quark model in a six-quark inverted triangular array that defines the global organization of the valence quarks, which determines the hadronic quantum numbers, the standard hadron quark model, and the Cabibbo-Kobayashi-Maskawa (CKM) matrix. Methods: The charm, bottom, top quarks are associated with power law line Y-intercept, n<sub>bem</sub> equal to 1;the strange and down quarks with n<sub>bem</sub> equal to 2;and the up quark with n<sub>bem</sub> equal to 3. An inverted equilateral triangular array with three rows arranged from upper row (triangle base) to bottom row (triangle vertex), is associated respectively with n<sub>bem</sub> numbers 1, 2, and 3. The novelty of our perspective thus defines a new global valence quark organization which supersedes the Standard hadron composite quark model. The quarks are ordered via relative mass, partial fractions, and n<sub>bem</sub> quantum number. The top row of our inverted triangle includes the c, b, and t quarks from left to right;the middle row depicts the d and s quarks;and the bottom row, the up quark. Results: Our array depicts a quantum generator of the global organization of the valence quarks defining the composite quark model. The vertices of the triangular array are the up quarks, the midpoints are the down quarks. All weak transitions are from a corner to a midpoint or vice versa. The standard 3 by 3 CKM matrix is generated from the new quark triangle with each up type quark (u, c, and t) transforming to each down type (d, s, and b), with their experimental flavor transition magnitudes given. Conclusion: A new quark quantum number, n<sub>bem</sub>, is an important discovery that generates a new proto-valence quark triangle that secondarily generates the composite quark model and the CKM matrix.展开更多
We study the 't Hooft coupling gt and the mass splitting of the ground-state baryons in terms of the large Noinspired quark model, by which the Hartree wavefunctions of light quarks are obtained. By fitting the spect...We study the 't Hooft coupling gt and the mass splitting of the ground-state baryons in terms of the large Noinspired quark model, by which the Hartree wavefunctions of light quarks are obtained. By fitting the spectra of decuplet and octet baryons, we obtain the 't Hooft coupling gt to be around 1.57. We generalize the scenario to the case of heavy baryons, such as Ac, gt values which does not deviate much from 1.57, as well as to the case of mesons with 9t far from that for baryons. The consequence is discussed.展开更多
The possibility of QQqq heavy-light four-quark bound states has been analyzed by means of the chiral SU(3) quark model,where Q is the heavy quark (c or b) and q is the light quark (u,d,or s).We obtain a bound state fo...The possibility of QQqq heavy-light four-quark bound states has been analyzed by means of the chiral SU(3) quark model,where Q is the heavy quark (c or b) and q is the light quark (u,d,or s).We obtain a bound state for the bbnn configuration with quantum number J^R=1^+,I=0 and for the ccnn(J^R=1+,I=0) configuration,which is not bound but slightly above the D~*D~* threshold (n is u or d quark).Meanwhile,we also conclude that a weakly bound state in bbnn system can also be found without considering the chiral quark interactions between the two light quarks, yet its binding energy is weaker than that with the chiral quark interactions.展开更多
魅力奇怪的家庭 D <SUP></SUP><SUB 的新成员 > sJ </SUB>(2317), D <SUB > sJ </SUB>(2460), 和 D <SUB > 有令人吃惊的性质的 s </SUB>(2632), ,正在质问现在的模型。许多理论解释...魅力奇怪的家庭 D <SUP></SUP><SUB 的新成员 > sJ </SUB>(2317), D <SUB > sJ </SUB>(2460), 和 D <SUB > 有令人吃惊的性质的 s </SUB>(2632), ,正在质问现在的模型。许多理论解释被奉献给这个问题。大多数作者建议他们不是常规 c 夸克模型状态,但是可能是 P 波浪 c 的四夸克的状态和一个四夸克的状态。在这个工作,我们跟随 four-quark-state 图画,并且学习 cn/cs 状态的群众(n 是 u 或 d 夸克) 在 chiral 苏(3 ) 夸克模型。数字结果表演有旋转同等值 J <SUP 的混合四夸克的状态(cn/cs ) 的团 > P </SUP>= 0 <SUP>+</SUP> 可能不是 D <SUB > s </SUB>(2632) 。同时,我们也结束那 D <SUP></SUP><SUB > sJ </SUB>(2317 ) 和 D <SUB > sJ </SUB>(2460 ) 不能作为纯四夸克的状态被解释。展开更多
The low-energy region kaon-pion S- and P-wave phase shifts with isospin I = 1/2 and I = 3/2 are dynamically studied in the chiral SU(3) quark model by solving a resonating group method equation. The model parameters a...The low-energy region kaon-pion S- and P-wave phase shifts with isospin I = 1/2 and I = 3/2 are dynamically studied in the chiral SU(3) quark model by solving a resonating group method equation. The model parameters are taken to be the values fitted by the energies of the baryon ground states and the kaon-nucleon elastic scattering phase shifts of different partial waves. As a preliminary study the s-channel q(-q) annihilation interactions are not included since they only act in the very short range and are subsequently assumed to be unimportant in the low-energy domain. The numerical results are in qualitative agreement with the experimental data.展开更多
The ratio between the anomalous magnetic moments of proton and neutron has recently been suggested to be connected to the ratio of proton momentum fractions carried by the valence quarks inside it. This moment fractio...The ratio between the anomalous magnetic moments of proton and neutron has recently been suggested to be connected to the ratio of proton momentum fractions carried by the valence quarks inside it. This moment fraction ratio is respectively evaluated by using constituent quark model and chiral quark model in order to check meson cloud effect. Our results show that the meson cloud effect is remarkable to the ratio of the proton momentum fractions, and therefore, this ratiois a sensitive test for the meson cloud effect as well as for the SU(6) symmetry breaking effect.展开更多
The N-N <sup>1</sup>S<sub>0</sub> scattering length differences Δα<sub>CSB</sub> and Δα<sub>CIH</sub> of the charge symmetrybreaking and charge independence breaking...The N-N <sup>1</sup>S<sub>0</sub> scattering length differences Δα<sub>CSB</sub> and Δα<sub>CIH</sub> of the charge symmetrybreaking and charge independence breaking are calculated by a resonating group method with aquark cluster model.By adding the QED-QCD interference effect to the quark mass differenceand the electromagnetic interaction,the Δα<sub>CSH</sub> and Δα<sub>CIH</sub> can be reproduced with modelparameters constrained by the hadron isomultiplet masses.展开更多
Radiative decays D((s))*→D((s))γare revisited in light of new experimental data from the BaBar and BESⅢCollaborations.The radiative couplings gD*Dγencoding nonperturbative QCD effects are calculated in the framewo...Radiative decays D((s))*→D((s))γare revisited in light of new experimental data from the BaBar and BESⅢCollaborations.The radiative couplings gD*Dγencoding nonperturbative QCD effects are calculated in the framework of the covariant confined quark model developed by us.We compare our results with other theoretical studies and experimental data.The couplings(in GeV-1)|g(D*+D+γ)|=0.45(9)and|g(D*0D0γ)|=1.72(34)calculated in our model agree with the corresponding experimental data|g(D*+D+γ)|=0.47(7)and|g(D*0D0γ)|=1.77(16).The most interesting case is the decay Ds*→Dsγ,for which a recent prediction based on light-cone sum rules at next-to-leading order|gDs*Dsγ|=0.60(19)deviates from the first(and only to date)lattice QCD result|gDs*Dsγ|=0.11(2)at nearly3σ.Our calculation yields|gDs*Dsγ|=0.29(6),which falls somehow between the two mentioned results,although it is larger than those predicted in other studies using quark models or QCD sum rules.展开更多
The S-wave■tetraquarks,with spin-parities■,and 2+,in both isoscalar and isovector sectors,are systematically studied using a chiral quark model.The meson-meson,diquark-antidiquark,and K-type arrangements of quarks a...The S-wave■tetraquarks,with spin-parities■,and 2+,in both isoscalar and isovector sectors,are systematically studied using a chiral quark model.The meson-meson,diquark-antidiquark,and K-type arrangements of quarks and all possible color wave functions are comprehensively considered.The four-body system is solved using the Gaussian expansion method,a highly efficient computational approach.Additonally,a complex-scaling formulation of the problem is established to disentangle bound,resonance,and scattering states.This theoretical framework has already been successfully applied in various tetra-and penta-quark systems.For the complete coupled channel and within the complex-range formulation,several narrow resonances of■systems are obtained,in each allowed■-channel,within the energy regions of■GeV and 5.7-6.7GeV,respectively.The predicted exotic states,which indicate a richer color structure when going towards multiquark systems beyond mesons and baryons,are expected to be confirmed in future high-energy particle and nuclear experiments.展开更多
Recently,some progress has been made in the experiments on double-heavy tetraquarks,such as T_(cc)reported by the LHCb Collaboration and Xccssreported by the Belle Collaboration.Coming on the heels of our previous wor...Recently,some progress has been made in the experiments on double-heavy tetraquarks,such as T_(cc)reported by the LHCb Collaboration and Xccssreported by the Belle Collaboration.Coming on the heels of our previous work about T_(cc) and T_(bb), we present a study on the bound and resonance states of their companions,QQqs(Q=c,b;q=u,s) tetraquarks with strange flavor in the chiral quark model.Two pictures,meson-meson and diquark-antidiquark ones,and their couplings were considered in our calculations.Isospin violation was neglected herein.Our numerical analysis indicated that the states ccus with 1/2(1^(+)) ald bbus with 1/2(1^(+)) are the most promising stable states against strong interactions.Besides,we found several resonance states for the double-heavy strange tetraquarks with the real scaling method.展开更多
In our previous studies,we analyzed the two-body strong decays of the low-lyingΩbaryon states within a chiral quark model.The results showed that the mass,total width,and two body decayΩ(2012)→■could be well repro...In our previous studies,we analyzed the two-body strong decays of the low-lyingΩbaryon states within a chiral quark model.The results showed that the mass,total width,and two body decayΩ(2012)→■could be well reproduced with the spin-parity J^(P)=3/2^(-)stateΩ^(*)|1P_(3/2^(-))>classified in the quark model.Stimulated by the new observations of the three-body decay processΩ(2012)^(-)→■at Belle,in the present study,we further investigate the three-body strong decayΩ^(*)|1P_(3/2^(-))>→■within the chiral quark model.It is found that theΩ^(*)|1P_(3/2^(-))>has a sizeable decay rate into the three-body final states■.When consideringΩ^(*)|1P_(3/2^(-))>as theΩ(2012)resonance,the predicted ratio■is close to the upper limit 11%measured by the Belle Collaboration in 2019;however,it is too small to be comparable to the recent measurement 0.97±0.24±0.07.In addition,the coupled-channel effects on the bare three-quark stateΩ^(*)|1P_(3/2^(-))>from nearby channels■are studied.Our theoretical results show that the coupled-channel effects onΩ^(*)|1P_(3/2^(-))>are not very large,and the molecular component is no more than 30%.To clarify the nature ofΩ(2012)resonance,precise measurements on the ratio■are needed,and further investigation on the effects of coupled channels is recommended.展开更多
The described structural model tries to answer some open questions such as: Why do quarks not exist in the open state? Where are the antiparticles from the Big Bang?
The six- and four-quark systems are studied in emphasized that the color confinement used in multiquark the framework of constituent quark models. It is system should be different from the one used in two- or three-qu...The six- and four-quark systems are studied in emphasized that the color confinement used in multiquark the framework of constituent quark models. It is system should be different from the one used in two- or three-quark system. For six-quark system, we look for △△ and △△ dibaryon resonances by calculating NN scattering phase shifts with explicit coupling to these dibaryon channels in quark delocalization and color screening model. The model gives a good description of low-energy NN properties and predicts IJP = 03+ and 01+ △△resonances, which can be promising candidates for the isoscalar ABC structure reported by the CELSIUS-WASA Collaboration. For tetraquark system, a flux-tube quark model with multi-body confinement interaction is employed to study Y(2175) as a tetraquark state. The Y(2175) with diquark-antidiquark structure has energy 2174 MeV which is very consistent with experimental data. The calculation shows that multi-body confinement potential may play a vital role in the multiquark system.展开更多
A chiral quark model is applied to calculate the spectra of pseudoscalar mesons η and η . By analyzing the obtained spectra, we find that the mesons η (2 1 S 0 ), η(4 1 S 0 ), η (3 1 S 0 ) and η (4 1 S 0 ...A chiral quark model is applied to calculate the spectra of pseudoscalar mesons η and η . By analyzing the obtained spectra, we find that the mesons η (2 1 S 0 ), η(4 1 S 0 ), η (3 1 S 0 ) and η (4 1 S 0 ) are the possible candidates of η(1760), X(1835), X(2120) and X(2370). The strong decay widths of these pseudoscalars to all the possible two-body decay channels are calculated within the framework of the 3 P 0 model. Although the total width of η (21S0 ) is compatible with the BES Collaboration's experimental value for η(1760), the partial decay width to ωω is too small, which is not consistent with the BES result. If X(1835) is interpreted as η(4 1 S 0 ), the total decay width is compatible with the experimental data, and the main decay modes will be πa 0 (980) and πa 0 (1450), which needs to be checked experimentally. The assignment of X(2120) and X(2370) to η (31S0 ) and η (41S0 ) is disfavored in the present calculation because of the incompatibility of the decay widths.展开更多
The phenomenological non-relativistic quark model has been employed to obtain the ground state masses of light vector mesons and their radially excited states and their decay widths.The full hamiltonian used in the in...The phenomenological non-relativistic quark model has been employed to obtain the ground state masses of light vector mesons and their radially excited states and their decay widths.The full hamiltonian used in the investigation has kinetic energy,the confinement potential and the one-gluon-exchange potential.A good agreement is obtained with the experimental masses and their leptonic decay widths.展开更多
文摘Purpose: The Harmonic Neutron Hypothesis, HNH, has demonstrated that many of the fundamental physical constants, including the quarks, are associated with partial harmonic fractional exponents, , of a fundamental frequency, v<sub>F</sub>. The model has shown that the properties of the quarks are based on a progression of prime number composites. They also fall on three separate power law lines related to integer factors of the Y-intercept, , of a fundamental electromagnetic line which is scaled by the Rydberg constant, R and Planck’s constant. The quark lines are scaled by the quantum number factors {1, 2, 3}, and their Y-intercepts are referred to as n<sub>bem</sub>. The goal is to present a new proto-quark model in a six-quark inverted triangular array that defines the global organization of the valence quarks, which determines the hadronic quantum numbers, the standard hadron quark model, and the Cabibbo-Kobayashi-Maskawa (CKM) matrix. Methods: The charm, bottom, top quarks are associated with power law line Y-intercept, n<sub>bem</sub> equal to 1;the strange and down quarks with n<sub>bem</sub> equal to 2;and the up quark with n<sub>bem</sub> equal to 3. An inverted equilateral triangular array with three rows arranged from upper row (triangle base) to bottom row (triangle vertex), is associated respectively with n<sub>bem</sub> numbers 1, 2, and 3. The novelty of our perspective thus defines a new global valence quark organization which supersedes the Standard hadron composite quark model. The quarks are ordered via relative mass, partial fractions, and n<sub>bem</sub> quantum number. The top row of our inverted triangle includes the c, b, and t quarks from left to right;the middle row depicts the d and s quarks;and the bottom row, the up quark. Results: Our array depicts a quantum generator of the global organization of the valence quarks defining the composite quark model. The vertices of the triangular array are the up quarks, the midpoints are the down quarks. All weak transitions are from a corner to a midpoint or vice versa. The standard 3 by 3 CKM matrix is generated from the new quark triangle with each up type quark (u, c, and t) transforming to each down type (d, s, and b), with their experimental flavor transition magnitudes given. Conclusion: A new quark quantum number, n<sub>bem</sub>, is an important discovery that generates a new proto-valence quark triangle that secondarily generates the composite quark model and the CKM matrix.
基金Supported by the National Natural Science Foundation of China under Grant No 11265014
文摘We study the 't Hooft coupling gt and the mass splitting of the ground-state baryons in terms of the large Noinspired quark model, by which the Hartree wavefunctions of light quarks are obtained. By fitting the spectra of decuplet and octet baryons, we obtain the 't Hooft coupling gt to be around 1.57. We generalize the scenario to the case of heavy baryons, such as Ac, gt values which does not deviate much from 1.57, as well as to the case of mesons with 9t far from that for baryons. The consequence is discussed.
基金supported in part by the National Natural Science Foundation of China under Grant Nos.10475087 and 10775146
文摘The possibility of QQqq heavy-light four-quark bound states has been analyzed by means of the chiral SU(3) quark model,where Q is the heavy quark (c or b) and q is the light quark (u,d,or s).We obtain a bound state for the bbnn configuration with quantum number J^R=1^+,I=0 and for the ccnn(J^R=1+,I=0) configuration,which is not bound but slightly above the D~*D~* threshold (n is u or d quark).Meanwhile,we also conclude that a weakly bound state in bbnn system can also be found without considering the chiral quark interactions between the two light quarks, yet its binding energy is weaker than that with the chiral quark interactions.
文摘The low-energy region kaon-pion S- and P-wave phase shifts with isospin I = 1/2 and I = 3/2 are dynamically studied in the chiral SU(3) quark model by solving a resonating group method equation. The model parameters are taken to be the values fitted by the energies of the baryon ground states and the kaon-nucleon elastic scattering phase shifts of different partial waves. As a preliminary study the s-channel q(-q) annihilation interactions are not included since they only act in the very short range and are subsequently assumed to be unimportant in the low-energy domain. The numerical results are in qualitative agreement with the experimental data.
文摘The ratio between the anomalous magnetic moments of proton and neutron has recently been suggested to be connected to the ratio of proton momentum fractions carried by the valence quarks inside it. This moment fraction ratio is respectively evaluated by using constituent quark model and chiral quark model in order to check meson cloud effect. Our results show that the meson cloud effect is remarkable to the ratio of the proton momentum fractions, and therefore, this ratiois a sensitive test for the meson cloud effect as well as for the SU(6) symmetry breaking effect.
基金The project supported by National Natural Science Foundation of China under Grant Nos. 10075056 and 90103020 and the CAS Knowledge Innovation Project under Grant No. KC2-SW-N02.
基金The project supported by National Natural Science Foundation of China under Grant Nos. 10475088 and 90103020, the CAS Knowledge Innovation Project under Grant No. KC2-SW-N02, and the Institute of Theoretical Physics The support from the Center of Theoretical Nuclear Physics, Lanzhou National Laboratory of Heavy Ion Accelerator is appreciated. 0ne of authors (Y.B. Dong) thanks the Department of Physics, Genova University for the hospitality. Authors are grateful to the discussions with M.M. Giannini and Santopinto.
基金The project supported by the NSF(19675018)SEDC of ChinaSSTC of China
文摘The N-N <sup>1</sup>S<sub>0</sub> scattering length differences Δα<sub>CSB</sub> and Δα<sub>CIH</sub> of the charge symmetrybreaking and charge independence breaking are calculated by a resonating group method with aquark cluster model.By adding the QED-QCD interference effect to the quark mass differenceand the electromagnetic interaction,the Δα<sub>CSH</sub> and Δα<sub>CIH</sub> can be reproduced with modelparameters constrained by the hadron isomultiplet masses.
基金Supported by Ho Chi Minh City University of Technology and Education(T2022-26)。
文摘Radiative decays D((s))*→D((s))γare revisited in light of new experimental data from the BaBar and BESⅢCollaborations.The radiative couplings gD*Dγencoding nonperturbative QCD effects are calculated in the framework of the covariant confined quark model developed by us.We compare our results with other theoretical studies and experimental data.The couplings(in GeV-1)|g(D*+D+γ)|=0.45(9)and|g(D*0D0γ)|=1.72(34)calculated in our model agree with the corresponding experimental data|g(D*+D+γ)|=0.47(7)and|g(D*0D0γ)|=1.77(16).The most interesting case is the decay Ds*→Dsγ,for which a recent prediction based on light-cone sum rules at next-to-leading order|gDs*Dsγ|=0.60(19)deviates from the first(and only to date)lattice QCD result|gDs*Dsγ|=0.11(2)at nearly3σ.Our calculation yields|gDs*Dsγ|=0.29(6),which falls somehow between the two mentioned results,although it is larger than those predicted in other studies using quark models or QCD sum rules.
基金supported by the National Natural Science Foundation of China(12305093,11535005,11775118)the Natural Science Foundation of Zhejiang Province,China(LQ22A050004)+1 种基金the Ministerio Español de Ciencia e Innovación(PID2019-107844GB-C22,PID2022-140440NB-C22)the Junta de Andalucía under contract Nos.Operativo FEDER Andalucía(2014-2020 UHU-1264517,P18-FR-5057 and also PAIDI FQM-370)。
文摘The S-wave■tetraquarks,with spin-parities■,and 2+,in both isoscalar and isovector sectors,are systematically studied using a chiral quark model.The meson-meson,diquark-antidiquark,and K-type arrangements of quarks and all possible color wave functions are comprehensively considered.The four-body system is solved using the Gaussian expansion method,a highly efficient computational approach.Additonally,a complex-scaling formulation of the problem is established to disentangle bound,resonance,and scattering states.This theoretical framework has already been successfully applied in various tetra-and penta-quark systems.For the complete coupled channel and within the complex-range formulation,several narrow resonances of■systems are obtained,in each allowed■-channel,within the energy regions of■GeV and 5.7-6.7GeV,respectively.The predicted exotic states,which indicate a richer color structure when going towards multiquark systems beyond mesons and baryons,are expected to be confirmed in future high-energy particle and nuclear experiments.
基金Supported partly by Natural Science Foundation of Jiangsu ProvinceChina (BK20221166)the National Natural Science Foundation of China (12205125,847145, 12205249, 1865019)。
文摘Recently,some progress has been made in the experiments on double-heavy tetraquarks,such as T_(cc)reported by the LHCb Collaboration and Xccssreported by the Belle Collaboration.Coming on the heels of our previous work about T_(cc) and T_(bb), we present a study on the bound and resonance states of their companions,QQqs(Q=c,b;q=u,s) tetraquarks with strange flavor in the chiral quark model.Two pictures,meson-meson and diquark-antidiquark ones,and their couplings were considered in our calculations.Isospin violation was neglected herein.Our numerical analysis indicated that the states ccus with 1/2(1^(+)) ald bbus with 1/2(1^(+)) are the most promising stable states against strong interactions.Besides,we found several resonance states for the double-heavy strange tetraquarks with the real scaling method.
基金Supported by the National Natural Science Foundation of China(12175065,12005060,12075288,11735003,11961141012)supported by the Youth Innovation Promotion Association CAS。
文摘In our previous studies,we analyzed the two-body strong decays of the low-lyingΩbaryon states within a chiral quark model.The results showed that the mass,total width,and two body decayΩ(2012)→■could be well reproduced with the spin-parity J^(P)=3/2^(-)stateΩ^(*)|1P_(3/2^(-))>classified in the quark model.Stimulated by the new observations of the three-body decay processΩ(2012)^(-)→■at Belle,in the present study,we further investigate the three-body strong decayΩ^(*)|1P_(3/2^(-))>→■within the chiral quark model.It is found that theΩ^(*)|1P_(3/2^(-))>has a sizeable decay rate into the three-body final states■.When consideringΩ^(*)|1P_(3/2^(-))>as theΩ(2012)resonance,the predicted ratio■is close to the upper limit 11%measured by the Belle Collaboration in 2019;however,it is too small to be comparable to the recent measurement 0.97±0.24±0.07.In addition,the coupled-channel effects on the bare three-quark stateΩ^(*)|1P_(3/2^(-))>from nearby channels■are studied.Our theoretical results show that the coupled-channel effects onΩ^(*)|1P_(3/2^(-))>are not very large,and the molecular component is no more than 30%.To clarify the nature ofΩ(2012)resonance,precise measurements on the ratio■are needed,and further investigation on the effects of coupled channels is recommended.
文摘The described structural model tries to answer some open questions such as: Why do quarks not exist in the open state? Where are the antiparticles from the Big Bang?
基金Supported by National Natural Science Foundation of China (10775072)Research Fund for the Doctoral Program of Higher Education of China (20070319007)
文摘The six- and four-quark systems are studied in emphasized that the color confinement used in multiquark the framework of constituent quark models. It is system should be different from the one used in two- or three-quark system. For six-quark system, we look for △△ and △△ dibaryon resonances by calculating NN scattering phase shifts with explicit coupling to these dibaryon channels in quark delocalization and color screening model. The model gives a good description of low-energy NN properties and predicts IJP = 03+ and 01+ △△resonances, which can be promising candidates for the isoscalar ABC structure reported by the CELSIUS-WASA Collaboration. For tetraquark system, a flux-tube quark model with multi-body confinement interaction is employed to study Y(2175) as a tetraquark state. The Y(2175) with diquark-antidiquark structure has energy 2174 MeV which is very consistent with experimental data. The calculation shows that multi-body confinement potential may play a vital role in the multiquark system.
基金Supported by National Natural Science Foundation of China(11035006,11175088)
文摘A chiral quark model is applied to calculate the spectra of pseudoscalar mesons η and η . By analyzing the obtained spectra, we find that the mesons η (2 1 S 0 ), η(4 1 S 0 ), η (3 1 S 0 ) and η (4 1 S 0 ) are the possible candidates of η(1760), X(1835), X(2120) and X(2370). The strong decay widths of these pseudoscalars to all the possible two-body decay channels are calculated within the framework of the 3 P 0 model. Although the total width of η (21S0 ) is compatible with the BES Collaboration's experimental value for η(1760), the partial decay width to ωω is too small, which is not consistent with the BES result. If X(1835) is interpreted as η(4 1 S 0 ), the total decay width is compatible with the experimental data, and the main decay modes will be πa 0 (980) and πa 0 (1450), which needs to be checked experimentally. The assignment of X(2120) and X(2370) to η (31S0 ) and η (41S0 ) is disfavored in the present calculation because of the incompatibility of the decay widths.
基金the DST for funding the project (Sanction No SR/S2/HEP-14/2006)
文摘The phenomenological non-relativistic quark model has been employed to obtain the ground state masses of light vector mesons and their radially excited states and their decay widths.The full hamiltonian used in the investigation has kinetic energy,the confinement potential and the one-gluon-exchange potential.A good agreement is obtained with the experimental masses and their leptonic decay widths.