标题： 共振三体衰变中的宽度效应：以$B$衰变为例 显示英文标题

标题： Width effects in resonant three-body decays: $B$ decay as an example

摘要： 对于通过具有大宽度的中间共振介导的三体强子衰变，我们展示了如何正确提取准二体衰变率，以便与相应的理论估计进行有意义的比较，使用几个$B$衰变作为具体例子。 我们计算了在QCD因子化方法中有限宽度效应的修正因子，并与没有弱动力学动量依赖性的实验参数化方法进行了比较。 尽管对于张量和矢量共振来说差异通常小于$10\%$，但对于标量共振来说可以高达$(25-40)\%$。 我们的发现实际上可以应用于一般的准二体衰变。 显示英文摘要

摘要： For three-body hadron decays mediated by intermediate resonances with large widths, we show how to properly extract the quasi-two-body decay rates for a meaningful comparison with the corresponding theoretical estimates, using several $B$ decays as explicit examples. We compute the correction factor from finite width effects in the QCD factorization approach, and make a comparison with that using the experimental parameterization in which the momentum dependence in the weak dynamics is absent. Although the difference is generally less than $10\%$ for tensor and vector resonances, it can be as large as $(25-40)\%$ for scalar resonances. Our finding can in fact be applied to general quasi-two-body decays.