论文标题
旋转轨道振幅，以任意自旋腐烂
Spin-orbit amplitudes for decays with arbitrary spin
论文作者
论文摘要
在本文中，我们提出了一种在轨道（$ L $）和旋转（$ s $）耦合方案中构建衰减幅度的方法，用于旋转的颗粒。对于仅涉及大量颗粒的$ 1 \ 2 $衰减，角度依赖性完全编码在角动量部分中，并且子颗粒的旋转在母粒子的其余框架中耦合，这仅贡献一个恒定的因素。对于顺序衰减，总振幅是由在自己母亲颗粒的其余框架中评估的两个$ 1 \ to2 $振幅构建的，然后将它们转换为普通框架，通常由某些Lorentz转换选择为实验室框架。这样，很容易添加可能的不同衰减链的幅度。如果在最终状态中出现无质量的颗粒，则以螺旋性表示极化，并相应地修改幅度。
In this paper, we propose a method to construct the decay amplitudes in the orbital ($L$) and spin ($S$) coupling scheme for particles with arbitrary spins. For the $1\to 2$ decay with only massive particles involved, the angular dependence is completely encoded in the angular momentum part, and the spins of daughter particles are coupled in the rest frame of the mother particle, which contributes only a constant factor. For the sequential decay, the total amplitude is constructed by the two $1\to2$ amplitudes evaluated in the rest frame of their own mother particles, and then they are transformed to the common frame, usually chosen as the laboratory frame, by certain Lorentz transformations. In this way, it is easy to add the amplitudes of possible different decay chains coherently. If massless particles show up in the final states, the polarizations are expressed in helicity basis and the amplitudes are modified correspondingly.
