论文标题
多体衰变分析 - 一种新的介子 - 梅森亚膜态的现象学模型
Multibody decay analyses -- a new phenomenological model for meson-meson subamplitudes
论文作者
论文摘要
梅森 - 梅森振幅本身很重要，并且在分析重 - 膜和tau衰变中也起着关键作用。在这项工作中，我们提出了一个适合所有$ su（3）$ Mesonic两体状态相互作用的新现象学模型，直到2 GEV左右。它的目的是取代进入QCD开发早前在1960年代生产的旧Isobar模型的人。我们的新提案与等轴模型中使用的幅度之间的唯一相似性涉及弹性策略中的向量共振。在其他情况下，尤其是涉及标量共振和耦合通道的情况下，Isobar模型与QCD后动力学不兼容。为了令人信服地支持这些主张并激励我们的方法，我们考虑到$ππ$振幅的应用，并在几种不同的情况下将我们的版本与Isobar模型进行比较。我们还表明，新模型清楚地表明了导致$ππ$相位在$ 1 \ $ 1，$ gev中观察到的急剧上升的机制。此处提出的现象学幅度适合给定通道中的任何数量的共振，并仅依靠质量和耦合常数作为自由参数。关于理论，它们在低能量的情况下融合了手性对称性，包括耦合的通道和尊重单位性。
Meson-meson amplitudes are important on their own and also play key roles in analyses of heavy-meson and tau decays. In this work we propose a new phenomenological model suited to all $SU(3)$ mesonic two-body final state interactions up to energies around 2 GeV. It is aimed at replacing those entering the old isobar model, produced in the 1960's, long before the development of QCD. The only similarity between our new proposal and amplitudes used in the isobar model concern vector resonances in the elastic regime. In other situations, especially those involving scalar resonances and coupled channels, the isobar model is not compatible with post-QCD dynamics. In order to support these claims convincingly and to motivate our approach, we consider applications to the $ππ$ amplitude and compare our version with the isobar model in several different instances. We also show that the new model provides a clear indication of the mechanism responsible for the sharp rise observed in the $ππ$ phase around $1\,$ GeV. The phenomenological amplitudes proposed here are suited to any number of resonances in a given channel and rely just on masses and coupling constants as free parameters. Concerning theory, they incorporate chiral symmetry at low energies, include coupled channels and respect unitarity whenever appropriate.
