We argue that the hypothesis that positive-parity charm meson resonances exhibit a compact tetraquark structure has some clear tension with recent lattice results for the S-waveπD system for an SU(3)flavor symmetric ...We argue that the hypothesis that positive-parity charm meson resonances exhibit a compact tetraquark structure has some clear tension with recent lattice results for the S-waveπD system for an SU(3)flavor symmetric setting.In particular,we show that such a diquark–anti-diquark tetraquark scenario would call for the presence of a state in the flavor[15]representation,not seen in the lattice analysis.Moreover,we show that analogous lattice data in the axial-vector channel are even more sensitive to the internal structure of these very interesting states.展开更多
We try to apply a constituent quark model (a variety chiral constituent quark model) and the resonating group approach for the multi-quark problems to compute the effective potential between the NN- in S-wave (the qua...We try to apply a constituent quark model (a variety chiral constituent quark model) and the resonating group approach for the multi-quark problems to compute the effective potential between the NN- in S-wave (the quarks in the nucleons N and N-, and the two nucleons relatively as well, are in S wave) so as to see the possibility if there may be a tight bound state of six quarks as indicated by a strong enhancement at threshold of pp- in J/ψ and B decays. The effective potential which we obtain in terms of the model and approach shows if the experimental enhancement is really caused by a tight S-wave bound state of six quarks, then the quantum number of the bound state is very likely to be I = 1, JPC= 0-+.展开更多
For the first time the low-lying J = 1/2 pentaquark states are investigated in the pseudoscalar-vector Skyrme model. Once the conventional baryon properties are fit, other states are predicted without any more adjusta...For the first time the low-lying J = 1/2 pentaquark states are investigated in the pseudoscalar-vector Skyrme model. Once the conventional baryon properties are fit, other states are predicted without any more adjustable parameters. Furthermore, both symmetry-breaking and decay operators are treated in full. In particular, we focus on the calculations of mass and decay width, and compare them with the experimental data available and relevant theoretical results obtained in other pictures. We recognize that the higher-order contributions, such as the 35 and/or 35 representation admixtures, are not negligible. Our analysis provides some valuable clues to the physical mechanisms, and the oncoming experimental search and/or confirmation could provide a sharp test of our proposal展开更多
In 2021,LHCb collaboration reported a very narrow state in the D^(0)D^(0)_(π)^(+)mass spectrum just below the D^(*+)D^(0)mass threshold.We consider the influence of the Castillejo–Dalitz–Dyson(CDD)pole in the scatt...In 2021,LHCb collaboration reported a very narrow state in the D^(0)D^(0)_(π)^(+)mass spectrum just below the D^(*+)D^(0)mass threshold.We consider the influence of the Castillejo–Dalitz–Dyson(CDD)pole in the scattering amplitude to derive a general treatment for the two-body final state interaction near its threshold.The line shape(or the energy dependent event distribution)are then obtained,where the parameters can be fixed by fitting to the experimental data on the D^(0)D^(0)_(π)^(+)mass spectrum.Within our method the data are quite well reproduced.The pole structure in the complex energy plane indicates that the T_(cc)state has a large portion of elementary degree of freedom(e.g.the compact tetraquark component)inside its hadron wave function.The compositeness as a measure of molecule component in its wave function is predicted to be 0.23_(-0.09)^(+0.40).Clearly,the non-molecular component takes a non-negligible or even dominant portion.展开更多
We calculate the D s 1 （2536） ^＋ decays into D＊K channels,including the decay D s 1 （2536） ＋ → D ＋ π-K ＋ through a virtual D＊0 in a constituent quark model.Widths and S/D amplitudes ratio are in agreement ...We calculate the D s 1 （2536） ^＋ decays into D＊K channels,including the decay D s 1 （2536） ＋ → D ＋ π-K ＋ through a virtual D＊0 in a constituent quark model.Widths and S/D amplitudes ratio are in agreement with the recent Belle and BABAR data,being the results sensitive to 1 P 1 and 3 P 1 mixture.展开更多
Based on five different ensembles of newly generated(2+1)-flavor configurations with pion mass of approximately mπ■(140-310)MeV,we present a lattice analysis of hidden-charm and hidden-strange hexaquarks with the qu...Based on five different ensembles of newly generated(2+1)-flavor configurations with pion mass of approximately mπ■(140-310)MeV,we present a lattice analysis of hidden-charm and hidden-strange hexaquarks with the quark content■.The correlation matrices of two types of operators with JPC=0++,0-+,1++and 1--are simulated to extract the masses of the hexaquark candidates,which are subsequently extrapolated to the physical pion mass and continuum limit.The results indicate that ground state masses are below the■threshold and provide a characteristic signal for the experimental discovery of hexaquark candidates,which may enrich the versatile structure of multiquarks;moreover,it is an indispensable step to decipher the nonperturbative nature of the fundamental interactions of quarks and gluons.展开更多
A QCD multiquark cluster system is studied in the relativistic harmonic oscillator potential model （RHOPM）, and the electromagnetic form factors of the pion, proton and deuteron in the RHOPM are predicted. The calcu...A QCD multiquark cluster system is studied in the relativistic harmonic oscillator potential model （RHOPM）, and the electromagnetic form factors of the pion, proton and deuteron in the RHOPM are predicted. The calculated theoretical results are then compared with existing experimental data, finding very good agreement between the theoretical predictions and experimental data for these three target particles. We claim that this model can be applied to study QCD hadronic properties, particularly neutron properties, and to find six-quark cluster and/or nine-quark cluster probabilities in light nuclei such as helium 3He and tritium 3H. This is a problem of particular importance and interest in quark nuclear physics.展开更多
基金supported in part by the National Natural Science Foundation of China(NSFC)under Grants Nos.12125507,12361141819,and 12047503the National Key R&D Program of China under Grant No.2023YFA1606703+1 种基金the Chinese Academy of Sciences(CAS)under Grants No.YSBR-101the CAS President’s International Fellowship Initiative(PIFI)under Grant No.2025PD0087 for the partial support。
文摘We argue that the hypothesis that positive-parity charm meson resonances exhibit a compact tetraquark structure has some clear tension with recent lattice results for the S-waveπD system for an SU(3)flavor symmetric setting.In particular,we show that such a diquark–anti-diquark tetraquark scenario would call for the presence of a state in the flavor[15]representation,not seen in the lattice analysis.Moreover,we show that analogous lattice data in the axial-vector channel are even more sensitive to the internal structure of these very interesting states.
文摘We try to apply a constituent quark model (a variety chiral constituent quark model) and the resonating group approach for the multi-quark problems to compute the effective potential between the NN- in S-wave (the quarks in the nucleons N and N-, and the two nucleons relatively as well, are in S wave) so as to see the possibility if there may be a tight bound state of six quarks as indicated by a strong enhancement at threshold of pp- in J/ψ and B decays. The effective potential which we obtain in terms of the model and approach shows if the experimental enhancement is really caused by a tight S-wave bound state of six quarks, then the quantum number of the bound state is very likely to be I = 1, JPC= 0-+.
基金The project partially supported by National Natural Science Foundation of China under Grant Nos. 10375039 and 90503008, the Doctoral Program Funds of the Ministry of Education, and the Research Fund of the Nuclear Theory Center of Heavy Ion Research Facility at Lanzhou of China.Acknowledgments We are grateful to Prof. H. Weigel for his useful program from E-mail exchanges.
文摘For the first time the low-lying J = 1/2 pentaquark states are investigated in the pseudoscalar-vector Skyrme model. Once the conventional baryon properties are fit, other states are predicted without any more adjustable parameters. Furthermore, both symmetry-breaking and decay operators are treated in full. In particular, we focus on the calculations of mass and decay width, and compare them with the experimental data available and relevant theoretical results obtained in other pictures. We recognize that the higher-order contributions, such as the 35 and/or 35 representation admixtures, are not negligible. Our analysis provides some valuable clues to the physical mechanisms, and the oncoming experimental search and/or confirmation could provide a sharp test of our proposal
基金supported by the National Natural Science Foundation of China under Project No.12275023。
文摘In 2021,LHCb collaboration reported a very narrow state in the D^(0)D^(0)_(π)^(+)mass spectrum just below the D^(*+)D^(0)mass threshold.We consider the influence of the Castillejo–Dalitz–Dyson(CDD)pole in the scattering amplitude to derive a general treatment for the two-body final state interaction near its threshold.The line shape(or the energy dependent event distribution)are then obtained,where the parameters can be fixed by fitting to the experimental data on the D^(0)D^(0)_(π)^(+)mass spectrum.Within our method the data are quite well reproduced.The pole structure in the complex energy plane indicates that the T_(cc)state has a large portion of elementary degree of freedom(e.g.the compact tetraquark component)inside its hadron wave function.The compositeness as a measure of molecule component in its wave function is predicted to be 0.23_(-0.09)^(+0.40).Clearly,the non-molecular component takes a non-negligible or even dominant portion.
基金Supported by Ministerio de Ciencia y Tecnología(FPA2007-65748)Junta de Castilla y León(SA-106A07,GR12)+1 种基金European Community-Research Infrastructure Integrating Activity"Study of Strongly Interacting Matter"(HadronPhysics2 Grant no.227431)Spanish Ingenio-Consolider 2010 Program CPAN(CSD2007-00042)
文摘We calculate the D s 1 （2536） ^＋ decays into D＊K channels,including the decay D s 1 （2536） ＋ → D ＋ π-K ＋ through a virtual D＊0 in a constituent quark model.Widths and S/D amplitudes ratio are in agreement with the recent Belle and BABAR data,being the results sensitive to 1 P 1 and 3 P 1 mixture.
基金supported by the National Natural Science Foundation of China(Grant Nos.11735010,11975127,11911530088,U2032102,12005130,12125503,and 12335003)supported by the Natural Science Foundation of Shanghai(Grant No.15DZ2272100)+2 种基金supported by Jiangsu Specially Appointed Professor Programsupported by the Strategic Priority Research Program of Chinese Academy of Sciences(Grant Nos.XDB34030303,and XDPB15)supported by the National Natural Science Foundation of China(NSFC)and Deutsche Forschungsgemeinschaft(DFG)joint grant(Grant No.12061131006)。
文摘Based on five different ensembles of newly generated(2+1)-flavor configurations with pion mass of approximately mπ■(140-310)MeV,we present a lattice analysis of hidden-charm and hidden-strange hexaquarks with the quark content■.The correlation matrices of two types of operators with JPC=0++,0-+,1++and 1--are simulated to extract the masses of the hexaquark candidates,which are subsequently extrapolated to the physical pion mass and continuum limit.The results indicate that ground state masses are below the■threshold and provide a characteristic signal for the experimental discovery of hexaquark candidates,which may enrich the versatile structure of multiquarks;moreover,it is an indispensable step to decipher the nonperturbative nature of the fundamental interactions of quarks and gluons.
基金Supported by National Natural Science Foundation of China(11365002)Guangxi Natural Science Foundation for Young Researchers(2013GXNSFBB053007,2011GXNSFA018140)+2 种基金Guangxi Education Department(2013ZD049)Guangxi Grant for Excellent Researchers(2011-54)Guangxi University of Science and Technology Foundation for PhDs(11Z16)
文摘A QCD multiquark cluster system is studied in the relativistic harmonic oscillator potential model （RHOPM）, and the electromagnetic form factors of the pion, proton and deuteron in the RHOPM are predicted. The calculated theoretical results are then compared with existing experimental data, finding very good agreement between the theoretical predictions and experimental data for these three target particles. We claim that this model can be applied to study QCD hadronic properties, particularly neutron properties, and to find six-quark cluster and/or nine-quark cluster probabilities in light nuclei such as helium 3He and tritium 3H. This is a problem of particular importance and interest in quark nuclear physics.
