Table of Baryons重子表
As an example of the notation in the column of decay modes, the sigma + decay mode is written which implies there are two common decay modes, 这表明存在两种常见的衰变模式,即 Σ⁺ → p + π⁰ 和 Σ⁺ → n + π⁺。
Particles which decay by the strong interaction typically do so on a time scale of about 10-23 seconds, and some of the baryons listed in the table above have lifetimes on the order of 10-10 seconds. The reason for those longer lifetimes is that they are forbidden by some kind of conservation law from decaying by the strong interaction, and must decay by the weak interaction. These decays involve quark transformations which can be represented by Feynman diagrams.There are dozens of other baryons (i.e., combinations of three quarks), but most of them decay by the strong interaction and are so short lived that they don't leave a measurable track in a bubble chamber or other detection device. These baryons have been detected as "resonances" or peaks in the probability for particle interactions. 通过强相互作用衰变的粒子通常在约10⁻²³秒的时间尺度上衰变,而表中列出的一些重子的寿命在10⁻¹⁰秒量级。这些较长的寿命是因为它们受某种守恒定律的禁止,无法通过强相互作用衰变,必须通过弱相互作用衰变。这些衰变涉及夸克变换,可以用费曼图表示。还有数十种其他重子(即由三个夸克组成的粒子),但大多数通过强相互作用衰变,且寿命极短,以至于在泡室或其他探测器中无法留下可测量的轨迹。这些重子已被检测为“共振”或在粒子相互作用概率中的峰。
作为衰变模式列中符号的示例,sigma + 衰变模式写作 pπ 0 , nπ + |
Index Particle concepts Reference Serway Ch. 47 Griffiths ![]() Particle Data Group 索引 粒子概念 参考 Serway 第47章 Griffiths 质子数据组 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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