标题： 类时区域中的超子电磁形式因子 显示英文标题

标题： Hyperon electromagnetic form factors in the timelike region

摘要： 超子（$\Lambda$，$\Sigma$，$\Xi$）在时空中区域的电磁形式因子，可通过反应$e^+e^- \to \bar YY$探测到，被研究。 重点在于接近反应阈值的能量处，这些形式因子的性质显著受最终$\bar YY$系统中相互作用的影响。 这种相互作用在计算中被考虑进去，使用了由 Jülich 小组为分析过去反应$\bar pp \to \bar YY$数据而构建的$\bar YY$势模型。 在接近阈值的能量下，有效形状因子的增强在$e^+e^- \to \bar \Lambda \Lambda$和$e^+e^- \to \bar \Sigma^0\Lambda$的实验中被观察到，并且这一现象得到了重现。 关于反应$e^+e^- \to \bar \Sigma^- \Sigma^+, \ \bar\Sigma^0\Sigma^0, \ \bar\Sigma^+\Sigma^-$，低能区的结果显示了三个通道之间微妙的相互作用，这是由$\bar\Sigma\Sigma$相互作用引起的。 在类时区域对超子$\Lambda$、$\Sigma$和$\Xi$的电磁形状因子$G_M$和$G_E$的预测被提出。 显示英文摘要

摘要： Electromagnetic form factors of hyperons ($\Lambda$, $\Sigma$, $\Xi$) in the timelike region, accessible in the reaction $e^+e^- \to \bar YY$, are studied. The focus is on energies close to the reaction thresholds, where the properties of these form factors are significantly influenced by the interaction in the final $\bar YY$ system. This interaction is taken into account in the calculation, utilizing $\bar YY$ potential models that have been constructed by the J\"ulich group for the analysis of data from the reaction $\bar pp \to \bar YY$ in the past. The enhancement of the effective form factor for energies close to the threshold, seen in experiments of $e^+e^- \to \bar \Lambda \Lambda$ and $e^+e^- \to \bar \Sigma^0\Lambda$, is reproduced. With regard to the reactions $e^+e^- \to \bar \Sigma^- \Sigma^+, \ \bar\Sigma^0\Sigma^0, \ \bar\Sigma^+\Sigma^-$ a delicate interplay between the three channels is observed in the results at low energies, caused by the $\bar\Sigma\Sigma$ interaction. Predictions for the electromagnetic form factors $G_M$ and $G_E$ in the timelike region are presented for the $\Lambda$, $\Sigma$, and $\Xi$ hyperons.