In this article, we perform a detailed study of the mass spectrum of the scalar doubly charmed and doubly bottom tetraquark states using the QCD sum rules.
In this article, we study the (1/2) ± and (3/2)± triply heavy baryon states in a systematic way by subtracting the contributions from the corresponding (1/2)■ and (3/2)■ triply heavy baryon states with the...In this article, we study the (1/2) ± and (3/2)± triply heavy baryon states in a systematic way by subtracting the contributions from the corresponding (1/2)■ and (3/2)■ triply heavy baryon states with the QCD sum rules, and make reasonable predictions for their masses.展开更多
The B-meson decay constant fB is an important component for studying the B-meson decays, which can be studied through QCD sum rules. We make a detailed discussion on f B from two sum rules up to next-to- leading order...The B-meson decay constant fB is an important component for studying the B-meson decays, which can be studied through QCD sum rules. We make a detailed discussion on f B from two sum rules up to next-to- leading order, i.e. sum rules I and II, which are derived from the conventional correlator and the correlator with chiral currents respectively. It is found that these two sum rules are consistent with each other. The sum rules H involves less non-perturbative condensates as that of sum rules I, and in principle, it can be more accurate if we know the dimensionfour gluon condensate well. It is found that fB decreases with the increment of mb, and to compare with the Belle experimental data on fB, both sum rules I and H prefer smaller pole b-quark mass, mb= 4.68 ± 0.07 GeV. By varying all the input parameters within their reasonable regions and by adding all the uncertainties in quadrature, we obtain fB=172-25^＋23 MeV for sum rules I and fB =214-34^26 MeV for sum rules П.展开更多
In this article, we study the pentaquark state Θ＋（1540） with a （scalar） diquark-（pseudoscalar） diquarkantiquark type interpolating current in the framework of the QCD sum rules approach by including the contri...In this article, we study the pentaquark state Θ＋（1540） with a （scalar） diquark-（pseudoscalar） diquarkantiquark type interpolating current in the framework of the QCD sum rules approach by including the contributions from the direct instantons. The numerical results indicate that the contributions from the direct instantons are very small and can be safely neglected.展开更多
In the present work, the masses of the decuplet baryons at finite temperature are investigated using thermM QCD sum rules. Making use of the quark propagator at finite temperature, we caiculate the spectral functions ...In the present work, the masses of the decuplet baryons at finite temperature are investigated using thermM QCD sum rules. Making use of the quark propagator at finite temperature, we caiculate the spectral functions to T8 order, and find that there are no contributions to the spectral functions at T8 order and the temperature corrections mainly come from that containing T4 ones. The calculations show very little temperature dependence of the masses below T =0.11 GeV. While above that vaJue, the masses decrease with increasing temperature. The results indicate that the hadron-quark phase transition temperature may be Tc ≥ 0.11 GeV for the decuplet bayons.展开更多
We systematically investigate the mass spectra of {Qs}{Q（＇）s} molecular states in the framework of QCD sum rules. The interpolating currents representing the molecular states are proposed. Technically, contribution...We systematically investigate the mass spectra of {Qs}{Q（＇）s} molecular states in the framework of QCD sum rules. The interpolating currents representing the molecular states are proposed. Technically, contributions of the operators up to dimension six are included in operator product expansion （OPE）. The masses for molecular states with various {Qs}{Q（＇）s} configurations are presented. The result 4.36 ± 0.08 Ge V for theDs＊ Ds0- ＊ molecular state is consistent with the mass 4350＋4.6 -5.1± 0.7 MeV of the newly observed X（4350）, which could support X（4350） interpreted as a D＊D＊so molecular state.展开更多
We construct both the scalar-diquark-scalar-diquark-antiquark type and axialvector-diquark-axialvector-diquark-antiquark type interpolating currents to study the charmed pentaquark:states suscu with J^(p)=1/2^(±)...We construct both the scalar-diquark-scalar-diquark-antiquark type and axialvector-diquark-axialvector-diquark-antiquark type interpolating currents to study the charmed pentaquark:states suscu with J^(p)=1/2^(±).We employ the QCD sum rules to investigate the masses and pole residues of the charmed pentaquark states by taking into account the vacuum condensates up to dimension 13 in the operator product expansion.Our calculation results indicate that the scalar-diquark-scalar-diquark-antiquark type and axialvector-diquark-axialvector-diquark-antiquark type charmed pentaquark states suscu with J^(p)=1/2^(-) can be possible candidates of the excited states observed in the LHCb collaboration.展开更多
In this article, we calculate the B＊→ηc form-factors with the three-point QCD sum rules, then study the semileptonic decays B＊→ηclυl. The tiny decay widths may be observed experimentally in the future at the LH...In this article, we calculate the B＊→ηc form-factors with the three-point QCD sum rules, then study the semileptonic decays B＊→ηclυl. The tiny decay widths may be observed experimentally in the future at the LHCb, while the B＊→ηc form-factors can be taken as basic input parameters in other phenomenologieal analysis.展开更多
In this article,we construct the color-singlet-color-singlet type currents and the color-singlet-colorsinglet-color-singlet type currents to study the scalar D*■*,D*D*tetraquark molecular states and the vector D*D*■...In this article,we construct the color-singlet-color-singlet type currents and the color-singlet-colorsinglet-color-singlet type currents to study the scalar D*■*,D*D*tetraquark molecular states and the vector D*D*■*,D*D*D*hexaquark molecular states with the QCD sum rules in details.In calculations,we choose the pertinent energy scales of the QCD spectral densities with the energy scale formula■for the tetraquark and hexaquark molecular states respectively in a consistent way.We obtain stable QCD sum rules for the scalar D*■*,D*D*tetraquark molecular states and the vector D*D*■*hexaquark molecular state,but cannot obtain stable QCD sum rules for the vector D*D*D*hexaquark molecular state.The connected(nonfactorizable)Feynman diagrams at the tree level(or the lowest order)and their induced diagrams via substituting the quark lines make positive contributions for the scalar D*D*tetraquark molecular state,but make negative or destructive contributions for the vector D*D*D*hexaquark molecular state.It is of no use or meaningless to distinguish the factorizable and nonfactorizable properties of the Feynman diagrams in the color space in the operator product expansion so as to interpret them in terms of the hadronic observables,we can only obtain information about the short-distance and long-distance contributions.展开更多
In this article, we study the light-flavor scalar and a^ial-vector diquark states in the vacuum and in the nuclear matter using the QCD sum rules in a systematic way, and make reasonable predictions for their masses i...In this article, we study the light-flavor scalar and a^ial-vector diquark states in the vacuum and in the nuclear matter using the QCD sum rules in a systematic way, and make reasonable predictions for their masses in the vacuum and in the nuclear matter.展开更多
In this article, we take the X(5568) as the diquark-antidiquark type tetraquark state with the spin-parity J^P= 0^+, construct the scalar-diquark-scalar-antidiquark type current, carry out the operator product expansi...In this article, we take the X(5568) as the diquark-antidiquark type tetraquark state with the spin-parity J^P= 0^+, construct the scalar-diquark-scalar-antidiquark type current, carry out the operator product expansion up to the vacuum condensates of dimension-10, and study the mass and pole residue in details with the QCD sum rules. We obtain the value M_X =(5.57 ± 0.12) Ge V, which is consistent with the experimental data. The present prediction favors assigning the X(5568) to be the scalar tetraquark state.展开更多
In this article, we study the masses and pole residues of the pseudoscalar-diquark-pseudoscalar-antidiquark type and vector-diquark-vector-antidiquark type scalar hidden-charm cucd （cucs） tetraquark states with QCD ...In this article, we study the masses and pole residues of the pseudoscalar-diquark-pseudoscalar-antidiquark type and vector-diquark-vector-antidiquark type scalar hidden-charm cucd （cucs） tetraquark states with QCD sum rules by taking into account the contributions of the vacuum condensates up to dimension-lO in the operator product expansion. The predicted masses can be confronted with the experimental data in the future. Possible decays of those tetraquark states are also discussed.展开更多
In this article, we take the vector charmonium-like state Y（4660） as a φ＇ fo（980） bound state （irrespective of the hadro-charmonium and the molecular state） tentatively, and study its mass using the QCD sum ru...In this article, we take the vector charmonium-like state Y（4660） as a φ＇ fo（980） bound state （irrespective of the hadro-charmonium and the molecular state） tentatively, and study its mass using the QCD sum rules. The numerical value My = 4.71 ±0.26 GeV is consistent with the experimental data. Considering the SU（3） symmetry of the light flavor quarks and the heavy quark symmetry, we also study the bound states φ＇a（400-1200）, γ′″ fo（980）, and γ′″σ（400-1200） with the QCD sum rules, and make reasonable predictions for their masses.展开更多
In this article, we calculate the contributions of the vacuum condensates up to dimension-10 in the operator product expansion, and study the C γμ- Cγνtype scalar, axial-vector and tensor tetraquark states in deta...In this article, we calculate the contributions of the vacuum condensates up to dimension-10 in the operator product expansion, and study the C γμ- Cγνtype scalar, axial-vector and tensor tetraquark states in details with the QCD sum rules. In calculations, we use the formula μ = √M^2X/ Y /Z-（2Mc）^2 to determine the energy scales of the QCD spectral densities. The predictions MJ =2=（4.02-0.09^＋0.09） GeV, MJ =1=（4.02-0.08^＋0.07） GeV favor assigning the Zc（4020） and Zc（4025） as the J^PC= 1^＋-or 2^＋＋diquark-antidiquark type tetraquark states, while the prediction MJ =0=（3.85-0.09^＋0.15） GeV disfavors assigning the Z（4050） and Z（4250） as the J^P C= 0^＋＋ diquark-antidiquark type tetraquark states. Furthermore, we discuss the strong decays of the 0^＋＋, 1^＋-, 2^＋＋diquark-antidiquark type tetraquark states in details.展开更多
In this article, we calculate the contribution from the nonfactorizable soft hadronic matrix element to the decay B^0→Xc1π^0 with the light-cone quantum chromo-dynamic （QCD） sum rules. The numerical results show t...In this article, we calculate the contribution from the nonfactorizable soft hadronic matrix element to the decay B^0→Xc1π^0 with the light-cone quantum chromo-dynamic （QCD） sum rules. The numerical results show that its contribution is rather large and should not be neglected. The total amplitudes lead to a branching fraction which is in agreement with the experimental data marginally.展开更多
In this study,we extend our previous study on the D^(*)D^(*)molecular states with J^(PC)=0^(++),1^(+-),and 2^(++)to investigate their two-body strong decays via the QCD sum rules based on rigorous quark-hadron duality...In this study,we extend our previous study on the D^(*)D^(*)molecular states with J^(PC)=0^(++),1^(+-),and 2^(++)to investigate their two-body strong decays via the QCD sum rules based on rigorous quark-hadron duality.We obtain the partial decay widths and,therefore,the total widths of the ground states with J^(PC)=0^(++),1^(+-),and 2^(++),which indicate that it is reasonable to assign X_(2)(4014)as the D^(*)D^(*) tetraquark molecular states with J^(PC)=2^(++).展开更多
We introduce a relative P-wave to construct the doubly charmed diquark(V) vector. Therefore, scalar and tensor four-quark currents were constructed to investigate the decay widths of the fully charmed tetraquark state...We introduce a relative P-wave to construct the doubly charmed diquark(V) vector. Therefore, scalar and tensor four-quark currents were constructed to investigate the decay widths of the fully charmed tetraquark states with J^(PC)= 0^(++), 1^(+-)and 2^(++) via quantum chromodynamics(QCD) sum rules. We observed that the total width of the ground state VV-type scalar tetraquark state is compatible with that of the X(6552) within uncertainties, and the branching ratios are quite different from that of the first radial excitation of the AA-type scalar tetraquark state. Other predictions can be verified in future experiments to shed light on the nature of the fully charmed tetraquark states.展开更多
In this article,we illustrate how to calculate the hadronic coupling constants of the pentaquark states with QCD sum rules based on rigorous quark-hadron quality.We then study the hadronic coupling constants of the lo...In this article,we illustrate how to calculate the hadronic coupling constants of the pentaquark states with QCD sum rules based on rigorous quark-hadron quality.We then study the hadronic coupling constants of the lowest diquark-diquark-antiquark type hidden-charm pentaquark state with spin-parity J^(P)=1^(1)/2in detail,and calculate the partial decay widths.The total widthτ(Pc)=14:32±3:31 MeV is compatible with the experimental valueτP_(c)(4312)=9:8±±2:7^(+3:7)_(-4:5)MeV from the LHCb collaboration,and favors assigning P_(c)(4312)the to be the pentaquark state with J^(P)=1^(1)/2.The hadronic coupling constants have the relation|G_(PD)++∑_(c)^(++)|=√2|GPD^(0)Σ_(c)^(+)|≫|G_(PD^(0))_(c)^(+)|,and favor the hadronic dressing mechanism.The P_(c)(4312)may have a diquark-diquark-antiquark type pentaquark core with the typical size of the-type baryon states.The strong couplings to the meson-baryon pairsD_(c)lead to some pentaquark molecule components,and the P_(c)(4312)may spend a rather large time as the molecular state.展开更多
In this talk, we give a short review of our recent works on studying the singly heavy baryon, doubly heavy baryon, and triply heavy baryon Spectra from QCD sum rules.
In this article, we calculate the form-factors of the transitions B → a1（1260）, b1（1235） in the leading-order approximation using the light-cone QCD sum rules. In calculations, we choose the chiral current to int...In this article, we calculate the form-factors of the transitions B → a1（1260）, b1（1235） in the leading-order approximation using the light-cone QCD sum rules. In calculations, we choose the chiral current to interpolate the B-meson, which has the outstanding advantage that the twist-3 light-cone distribution amplitudes of the axial-vector mesons makes no contributions, and the resulting sum rules for the form-factors suffer from far fewer uncertainties. Then we study the semi-leptonic decays B → a1（1260） lvl, b1（1235） lvl （l=e,μ,τ）, and make predictions for the differential decay widths and decay widths, which can be compared with the experimental data in the coming future展开更多
基金Supported by National Natural Science Foundation of China under Grant Nos.10775051,11075053Program for New Century Excellent Talents in University under Grant No.NCET-07-0282the Fundamental Research Funds for the Central Universities
文摘In this article, we perform a detailed study of the mass spectrum of the scalar doubly charmed and doubly bottom tetraquark states using the QCD sum rules.
基金Supported by National Natural Science Foundation under Grant No.11075053the Fundamental Research Funds for the Central Universities
文摘In this article, we study the (1/2) ± and (3/2)± triply heavy baryon states in a systematic way by subtracting the contributions from the corresponding (1/2)■ and (3/2)■ triply heavy baryon states with the QCD sum rules, and make reasonable predictions for their masses.
基金Supported by Natural Science Foundation Project of CQ CSTC under Grant No.2008BB0298by Natural Science Foundation of China under Grant Nos.10805082 and 11075225by the Fundamental Research Funds for the Central Universities under Grant No.CDJZR101000616
文摘The B-meson decay constant fB is an important component for studying the B-meson decays, which can be studied through QCD sum rules. We make a detailed discussion on f B from two sum rules up to next-to- leading order, i.e. sum rules I and II, which are derived from the conventional correlator and the correlator with chiral currents respectively. It is found that these two sum rules are consistent with each other. The sum rules H involves less non-perturbative condensates as that of sum rules I, and in principle, it can be more accurate if we know the dimensionfour gluon condensate well. It is found that fB decreases with the increment of mb, and to compare with the Belle experimental data on fB, both sum rules I and H prefer smaller pole b-quark mass, mb= 4.68 ± 0.07 GeV. By varying all the input parameters within their reasonable regions and by adding all the uncertainties in quadrature, we obtain fB=172-25^＋23 MeV for sum rules I and fB =214-34^26 MeV for sum rules П.
基金The project supported by National Natural Science Foundation of China under Grant No. 10405009 and the Key Program Foundation of North China Electric Power University
文摘In this article, we study the pentaquark state Θ＋（1540） with a （scalar） diquark-（pseudoscalar） diquarkantiquark type interpolating current in the framework of the QCD sum rules approach by including the contributions from the direct instantons. The numerical results indicate that the contributions from the direct instantons are very small and can be safely neglected.
基金Supported by the National Natural Science Foundation of China under Grant Nos.11475257,11275268National University of Defense Technology Foundation under Grant No.JC14-02-05
文摘In the present work, the masses of the decuplet baryons at finite temperature are investigated using thermM QCD sum rules. Making use of the quark propagator at finite temperature, we caiculate the spectral functions to T8 order, and find that there are no contributions to the spectral functions at T8 order and the temperature corrections mainly come from that containing T4 ones. The calculations show very little temperature dependence of the masses below T =0.11 GeV. While above that vaJue, the masses decrease with increasing temperature. The results indicate that the hadron-quark phase transition temperature may be Tc ≥ 0.11 GeV for the decuplet bayons.
基金Supported by the National Natural Science Foundation of China under Grant Nos.10675167 and 10975184
文摘We systematically investigate the mass spectra of {Qs}{Q（＇）s} molecular states in the framework of QCD sum rules. The interpolating currents representing the molecular states are proposed. Technically, contributions of the operators up to dimension six are included in operator product expansion （OPE）. The masses for molecular states with various {Qs}{Q（＇）s} configurations are presented. The result 4.36 ± 0.08 Ge V for theDs＊ Ds0- ＊ molecular state is consistent with the mass 4350＋4.6 -5.1± 0.7 MeV of the newly observed X（4350）, which could support X（4350） interpreted as a D＊D＊so molecular state.
基金supported by National Natural Science Foundation,Grant Number 11775079.
文摘We construct both the scalar-diquark-scalar-diquark-antiquark type and axialvector-diquark-axialvector-diquark-antiquark type interpolating currents to study the charmed pentaquark:states suscu with J^(p)=1/2^(±).We employ the QCD sum rules to investigate the masses and pole residues of the charmed pentaquark states by taking into account the vacuum condensates up to dimension 13 in the operator product expansion.Our calculation results indicate that the scalar-diquark-scalar-diquark-antiquark type and axialvector-diquark-axialvector-diquark-antiquark type charmed pentaquark states suscu with J^(p)=1/2^(-) can be possible candidates of the excited states observed in the LHCb collaboration.
基金Supported by National Natural Science Foundation under Grant Nos.11075053,11375063the Fundamental Research Funds for the Central Universities
文摘In this article, we calculate the B＊→ηc form-factors with the three-point QCD sum rules, then study the semileptonic decays B＊→ηclυl. The tiny decay widths may be observed experimentally in the future at the LHCb, while the B＊→ηc form-factors can be taken as basic input parameters in other phenomenologieal analysis.
基金supported by National Natural Science Foundation,Grant Number 11775079。
文摘In this article,we construct the color-singlet-color-singlet type currents and the color-singlet-colorsinglet-color-singlet type currents to study the scalar D*■*,D*D*tetraquark molecular states and the vector D*D*■*,D*D*D*hexaquark molecular states with the QCD sum rules in details.In calculations,we choose the pertinent energy scales of the QCD spectral densities with the energy scale formula■for the tetraquark and hexaquark molecular states respectively in a consistent way.We obtain stable QCD sum rules for the scalar D*■*,D*D*tetraquark molecular states and the vector D*D*■*hexaquark molecular state,but cannot obtain stable QCD sum rules for the vector D*D*D*hexaquark molecular state.The connected(nonfactorizable)Feynman diagrams at the tree level(or the lowest order)and their induced diagrams via substituting the quark lines make positive contributions for the scalar D*D*tetraquark molecular state,but make negative or destructive contributions for the vector D*D*D*hexaquark molecular state.It is of no use or meaningless to distinguish the factorizable and nonfactorizable properties of the Feynman diagrams in the color space in the operator product expansion so as to interpret them in terms of the hadronic observables,we can only obtain information about the short-distance and long-distance contributions.
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 light-flavor scalar and a^ial-vector diquark states in the vacuum and in the nuclear matter using the QCD sum rules in a systematic way, and make reasonable predictions for their masses in the vacuum and in the nuclear matter.
基金Supported by National Natural Science Foundation under Grant No.11375063Natural Science Foundation of Hebei Province under Grant No.A2014502017
文摘In this article, we take the X(5568) as the diquark-antidiquark type tetraquark state with the spin-parity J^P= 0^+, construct the scalar-diquark-scalar-antidiquark type current, carry out the operator product expansion up to the vacuum condensates of dimension-10, and study the mass and pole residue in details with the QCD sum rules. We obtain the value M_X =(5.57 ± 0.12) Ge V, which is consistent with the experimental data. The present prediction favors assigning the X(5568) to be the scalar tetraquark state.
基金Supported by the National Natural Science Foundation of China under Grant No.11375063the Fundamental Research Funds for the Central Universities under Grant Nos.2016MS155 and 2016MS133
文摘In this article, we study the masses and pole residues of the pseudoscalar-diquark-pseudoscalar-antidiquark type and vector-diquark-vector-antidiquark type scalar hidden-charm cucd （cucs） tetraquark states with QCD sum rules by taking into account the contributions of the vacuum condensates up to dimension-lO in the operator product expansion. The predicted masses can be confronted with the experimental data in the future. Possible decays of those tetraquark states are also discussed.
基金Supported by National Natural Science Foundation under Grant No.10775051 Program for New Century Excellent Talents in University under Grant No.NCET-07-0282 Project Supported by Chinese Universities Scientific Fund
文摘In this article, we take the vector charmonium-like state Y（4660） as a φ＇ fo（980） bound state （irrespective of the hadro-charmonium and the molecular state） tentatively, and study its mass using the QCD sum rules. The numerical value My = 4.71 ±0.26 GeV is consistent with the experimental data. Considering the SU（3） symmetry of the light flavor quarks and the heavy quark symmetry, we also study the bound states φ＇a（400-1200）, γ′″ fo（980）, and γ′″σ（400-1200） with the QCD sum rules, and make reasonable predictions for their masses.
基金Supported by National Natural Science Foundation of China under Grant No.11375063Natural Science Foundation of Hebei Province under Grant No.A2014502017
文摘In this article, we calculate the contributions of the vacuum condensates up to dimension-10 in the operator product expansion, and study the C γμ- Cγνtype scalar, axial-vector and tensor tetraquark states in details with the QCD sum rules. In calculations, we use the formula μ = √M^2X/ Y /Z-（2Mc）^2 to determine the energy scales of the QCD spectral densities. The predictions MJ =2=（4.02-0.09^＋0.09） GeV, MJ =1=（4.02-0.08^＋0.07） GeV favor assigning the Zc（4020） and Zc（4025） as the J^PC= 1^＋-or 2^＋＋diquark-antidiquark type tetraquark states, while the prediction MJ =0=（3.85-0.09^＋0.15） GeV disfavors assigning the Z（4050） and Z（4250） as the J^P C= 0^＋＋ diquark-antidiquark type tetraquark states. Furthermore, we discuss the strong decays of the 0^＋＋, 1^＋-, 2^＋＋diquark-antidiquark type tetraquark states in details.
基金supported by the National Natural Science Foundation of China (Grant No 10775051)the Program for New Century Excellent Talents in University of China (Grant No NCET-07-0282)
文摘In this article, we calculate the contribution from the nonfactorizable soft hadronic matrix element to the decay B^0→Xc1π^0 with the light-cone quantum chromo-dynamic （QCD） sum rules. The numerical results show that its contribution is rather large and should not be neglected. The total amplitudes lead to a branching fraction which is in agreement with the experimental data marginally.
基金Supported by the National Natural Science Foundation(12175068)。
文摘In this study,we extend our previous study on the D^(*)D^(*)molecular states with J^(PC)=0^(++),1^(+-),and 2^(++)to investigate their two-body strong decays via the QCD sum rules based on rigorous quark-hadron duality.We obtain the partial decay widths and,therefore,the total widths of the ground states with J^(PC)=0^(++),1^(+-),and 2^(++),which indicate that it is reasonable to assign X_(2)(4014)as the D^(*)D^(*) tetraquark molecular states with J^(PC)=2^(++).
基金Supported by the National Natural Science Foundation (12175068)the Fundamental Research Funds for the Central Universities。
文摘We introduce a relative P-wave to construct the doubly charmed diquark(V) vector. Therefore, scalar and tensor four-quark currents were constructed to investigate the decay widths of the fully charmed tetraquark states with J^(PC)= 0^(++), 1^(+-)and 2^(++) via quantum chromodynamics(QCD) sum rules. We observed that the total width of the ground state VV-type scalar tetraquark state is compatible with that of the X(6552) within uncertainties, and the branching ratios are quite different from that of the first radial excitation of the AA-type scalar tetraquark state. Other predictions can be verified in future experiments to shed light on the nature of the fully charmed tetraquark states.
基金Supported by National Natural Science Foundation of China(11775079)。
文摘In this article,we illustrate how to calculate the hadronic coupling constants of the pentaquark states with QCD sum rules based on rigorous quark-hadron quality.We then study the hadronic coupling constants of the lowest diquark-diquark-antiquark type hidden-charm pentaquark state with spin-parity J^(P)=1^(1)/2in detail,and calculate the partial decay widths.The total widthτ(Pc)=14:32±3:31 MeV is compatible with the experimental valueτP_(c)(4312)=9:8±±2:7^(+3:7)_(-4:5)MeV from the LHCb collaboration,and favors assigning P_(c)(4312)the to be the pentaquark state with J^(P)=1^(1)/2.The hadronic coupling constants have the relation|G_(PD)++∑_(c)^(++)|=√2|GPD^(0)Σ_(c)^(+)|≫|G_(PD^(0))_(c)^(+)|,and favor the hadronic dressing mechanism.The P_(c)(4312)may have a diquark-diquark-antiquark type pentaquark core with the typical size of the-type baryon states.The strong couplings to the meson-baryon pairsD_(c)lead to some pentaquark molecule components,and the P_(c)(4312)may spend a rather large time as the molecular state.
基金Supported by National Natural Science Foundation of China (10675167)
文摘In this talk, we give a short review of our recent works on studying the singly heavy baryon, doubly heavy baryon, and triply heavy baryon Spectra from QCD sum rules.
基金Supported by National Natural Science Foundation of China(10735080,10805082,10675098,11075053)the Fundamental Research Funds for the Central Universities
文摘In this article, we calculate the form-factors of the transitions B → a1（1260）, b1（1235） in the leading-order approximation using the light-cone QCD sum rules. In calculations, we choose the chiral current to interpolate the B-meson, which has the outstanding advantage that the twist-3 light-cone distribution amplitudes of the axial-vector mesons makes no contributions, and the resulting sum rules for the form-factors suffer from far fewer uncertainties. Then we study the semi-leptonic decays B → a1（1260） lvl, b1（1235） lvl （l=e,μ,τ）, and make predictions for the differential decay widths and decay widths, which can be compared with the experimental data in the coming future
