In this work, we use the Born-Oppenheimer approximation, where the potential between atoms can be approximated as a function of distance between the two nuclei, to study the four-quark bound states. By this approximat...In this work, we use the Born-Oppenheimer approximation, where the potential between atoms can be approximated as a function of distance between the two nuclei, to study the four-quark bound states. By this approximation, Heitler and London calculated the spectrum of the hydrogen molecule, which includes two protons （heavy） and two electrons （light）. Cenerally, the observed exotic mesons Zb（10610）, ZD（10650）, Zc（3900） and Zc（4020） （Zc（4025）） may be molecular states made of two physical mesons and/or diquark-anti-diquark structures. Analogous to the Heitler-London method for calculating the mass of the hydrogen molecule, we investigate whether there exist energy minima for these two structures. Contrary to the hydrogen molecule case where only the spin-triplet possesses an energy minimum, there exist minima for both of these states. This implies that both molecule and tetraquark states can be stable objects. Since they have the same quantum numbers, however, the two states may mix to result in the physical states. A consequence would be that partner exotic states co-existing with ZD（10610）, Zb（]0650）, Zc（3900） and Zc（4020） （Zc（4025）） are predicted and should be experimentally observed.展开更多
We systematically construct all the tetraquark currents of J^(PC)=1^(++) with the quark configurations[cq][cq],[cq][qc],and[cc][qq](q=u/d).Their relations are derived using the Fierz rearrangement of the Dirac and col...We systematically construct all the tetraquark currents of J^(PC)=1^(++) with the quark configurations[cq][cq],[cq][qc],and[cc][qq](q=u/d).Their relations are derived using the Fierz rearrangement of the Dirac and color indices,through which we study decay properties of the X(3872)under both the compact tetraquark and hadronic molecule interpretations.We conduct a search for the X(3872)→χ_(c0)π,η_(c)ππ,and χ_(c1)ππ decay processes in particle experiments.展开更多
基金Supported by National Natural Science Foundation of China(11375128)
文摘In this work, we use the Born-Oppenheimer approximation, where the potential between atoms can be approximated as a function of distance between the two nuclei, to study the four-quark bound states. By this approximation, Heitler and London calculated the spectrum of the hydrogen molecule, which includes two protons （heavy） and two electrons （light）. Cenerally, the observed exotic mesons Zb（10610）, ZD（10650）, Zc（3900） and Zc（4020） （Zc（4025）） may be molecular states made of two physical mesons and/or diquark-anti-diquark structures. Analogous to the Heitler-London method for calculating the mass of the hydrogen molecule, we investigate whether there exist energy minima for these two structures. Contrary to the hydrogen molecule case where only the spin-triplet possesses an energy minimum, there exist minima for both of these states. This implies that both molecule and tetraquark states can be stable objects. Since they have the same quantum numbers, however, the two states may mix to result in the physical states. A consequence would be that partner exotic states co-existing with ZD（10610）, Zb（]0650）, Zc（3900） and Zc（4020） （Zc（4025）） are predicted and should be experimentally observed.
基金supported by the National Natural Science Foundation of China under Grant No.11722540 and No.12075019the Jiangsu Provincial Double-Innovation Program under Grant No.JSSCRC2021488the Fundamental Research Funds for the Central Universities。
文摘We systematically construct all the tetraquark currents of J^(PC)=1^(++) with the quark configurations[cq][cq],[cq][qc],and[cc][qq](q=u/d).Their relations are derived using the Fierz rearrangement of the Dirac and color indices,through which we study decay properties of the X(3872)under both the compact tetraquark and hadronic molecule interpretations.We conduct a search for the X(3872)→χ_(c0)π,η_(c)ππ,and χ_(c1)ππ decay processes in particle experiments.
