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摘要:
对S波自旋单态底夸克偶素衰变到粲夸克对进行了研究,同时还研究了S波自旋单态和自旋三重态底夸克偶素衰变到D介子对。利用BaBar实验组测量得到的自旋三重态底夸克偶素衰变到D介子分支比的数据,发现自旋三重态底夸克偶素的色八重态矩阵元远小于理论预言,理论预言要比实验上限大20倍以上;得到S波自旋单态底夸克偶素衰变到粲夸克对的分支比的理论预言,可以进行实验测量从而研究色八重态矩阵元;得到S波自旋单态底夸克偶素衰变到D介子对的分支比的理论预言,与其他理论预言差异较大。这些预言可以通过BelleⅡ的实验进行验证,从而得到更多强子化的信息。
Abstract:The decay of S-wave spin singlet bottomonium state to charm quark pair is studied, and the decay of S-wave spin singlet state and triplet bottomonium state to D meson pair is studied. By using the branching ratio of the decay of S-wave spin triplet bottomonium state to D meson measured by the BaBar Collaboration, it is found that the color octet matrix element of the S-wave spin triplet bottomonium state is much smaller than the theoretical prediction, and the theoretical prediction is a factor of 20 times larger than the experimental upper limit. The theoretical predictions of the branching ratio of S-wave spin singlet bottomonium state to charm quark pair can be used to probe the color octet mechanism. The theoretical predictions of the branching ratio of S-wave spin singlet bottomonium state to D meson pair are different from those of other literature. These predictions can be validated by Belle Ⅱ Collaboration to obtain more information about hadronization.
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Key words:
- bottomonium /
- charm quark /
- D meson /
- color octet mechanism /
- fragmentation function
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