论文标题
$λ$ hyperon的电磁形式的分散理论分析
Dispersion-theoretical analysis of the electromagnetic form factors of the $Λ$ hyperon
论文作者
论文摘要
$λ$ hyperon在时间样区域中的电磁形式因素是通过对歼灭过程的横截面的世界数据的分散理论分析$ e^+e^ - \ to \barλλ$确定的。光谱函数由狭窄和宽阔的媒介膜杆的叠加表示。我们测试了光谱函数的不同方案，并在类似时间的区域中获得了世界数据的良好描述。提取的形式因素中的不确定性是通过自举抽样方法估算的。由于缺乏数据，形态因素向类似太空区域的分析延续引入了较大的错误。当手性扰动理论的电$λ$半径被视为约束时，磁性半径被预测为$ r_m = 0.681 \ pm 0.002 $ fm。我们还将各种矢量介子提取到巴属耦合常数。
The electromagnetic form factors of the $Λ$ hyperon in the time-like region are determined precisely through a dispersion-theoretical analysis of the world data for the cross section of the annihilation process $e^+e^-\to \barΛΛ$. The spectral function is represented by a superposition of narrow and broad vector meson poles. We test different scenarios for the spectral function and obtain a good description of the world data in the time-like region. The uncertainties in the extracted form factors are estimated by means of the bootstrap sampling method. The analytical continuation of the form factors to the space-like region introduces large errors due to the lack of data. When the electric $Λ$ radius from chiral perturbation theory is taken as a constraint, the magnetic radius is predicted as $r_M = 0.681 \pm 0.002$ fm. We also extract various vector meson to baryon coupling constants.
