论文标题
保留重叠多通道状态的单位性：Breit-Wigner与K矩阵 - 比较，优势和缺点
Preserving unitarity for overlapping multichannel states: Breit-Wigner versus K matrix -- comparison, advantages and disadvantages
论文作者
论文摘要
K-Matrix方法通常用于描述重叠的共振。它保证了散射矩阵的单位性，但其参数不是共振质量和宽度。目前尚不清楚如何将谐振和背景贡献分开，并在相移方面描述背景。 BREIT-WIGNER（BW）方法具有具有直接实验含义的参数，但简单的BW函数总和并不统一。我们通过考虑BW功能的干扰来展示如何构建单一S-Matrix。该方法简单明了，可以将背景添加到标准量子力学形式的共振幅度中。在示例中，我们进行了K-Matrix和单一BW诉讼之间的比较。
The K-matrix method is often used to describe overlapping resonances. It guarantees the unitarity of the scattering matrix but its parameters are not resonances masses and widths. It is also unclear how to separate resonant and background contributions and to describe background in terms of phase shifts. The Breit-Wigner (BW) approach operates with parameters having direct experimental meaning but a simple sum of the BW functions is not unitary. We show how to construct the unitary S-matrix by taking into account the interference of the BW functions. The method is simple and straightforward, background can be added to resonance amplitudes in the standard quantum mechanics form. In examples we give a comparison between the K-matrix and unitary BW-approaches.
