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arXiv 2006.08650hep-phhep-ex
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双重四夸克态的质量及其误差线

Masses of Doubly Heavy Tetraquarks with Error Bars

Eric Braaten, Li-Ping He, Abhishek Mohapatra

摘要:

在重夸克极限下,一个二重重子或一个二重四夸克中的两个重夸克被它们的色库仑势束缚成一个紧致的双夸克。通过QCD的近似重夸克-双夸克对称性,二重强子与用重反夸克代替重双夸克得到的重强子有关。有效场论可以用来把单重强子和二重强子的质量展开成重夸克质量的倒数。利用重夸克-双夸克对称性,可以从重介子、重子和二重重子的展开式中确定二重四夸克展开式中的系数。我们用实验测得的重介子和重子的质量以及用格点量子色动力学计算的重重子的质量作为输入,预测了基态重四夸克态的质量,并给出了误差条.唯一被预测在强衰变中稳定的重四夸克是具有轻味的$bb$四夸克$\bar u \bar d$、$\bar s \bar u$和$\bar s \bar d$。

英文摘要:

In the heavy-quark limit, the two heavy quarks in a doubly heavy baryon or a doubly heavy tetraquark are bound by their color-Coulomb potential into a compact diquark. The doubly heavy hadrons are related by the approximate heavy-quark--diquark symmetry of QCD to the heavy hadrons obtained by replacing the heavy diquark by a heavy antiquark. Effective field theories can be used to expand the masses of singly heavy hadrons and doubly heavy hadrons in inverse powers of the heavy quark masses. The coefficients in the expansions for doubly heavy tetraquarks can be determined from those for heavy mesons, heavy baryons, and doubly heavy baryons using heavy-quark--diquark symmetry. We predict the masses of the ground-state doubly heavy tetraquarks with error bars using as inputs the masses of heavy mesons and heavy baryons measured in experiments and the masses of doubly heavy baryons calculated using lattice QCD. The only doubly heavy tetraquarks predicted to be stable with respect to strong decays are $bb$ tetraquarks with light flavor $\bar u \bar d$, $\bar s \bar u$ and $\bar s \bar d$.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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