Nonperturbative structure of the polarized nucleon sea
Nonperturbative structure of the polarized nucleon sea
复制标题
极化核子海的非微扰结构
DOI：
10.1103/physrevd.68.074002
复制
发表时间：
2003
影响因子：
5
通讯作者：
A. I. Signal
中科院分区：
文献类型：
--
作者：
F. Cao;A. I. Signal
利用介子云模型，通过计算核子海的部分子分布函数，研究了极化核子的味道和夸克-反夸克结构。我们发现轻反夸克海中的SU(2)味对称性和奇异夸克海中的夸克-反夸克对称性都被破坏了，即$\Delta\Ubar<；\Delta S<；\Delta\sbar$。奇异海洋的极化被发现是正的，这与以前的分析相矛盾。我们预测极化奇异夸克海中的夸克-反夸克不对称性比未极化奇异夸克海洋中的夸克-反夸克不对称性大得多。我们对极化光夸克海和极化奇异夸克海的结果与最近的Hermes数据是一致的。
We investigate the flavour and quark-antiquark structure of the polarized nucleon by calculating the parton distribution functions of the nucleon sea using the meson cloud model. We find that the SU(2) flavor symmetry in the light antiquark sea and quark-antiquark symmetry in the strange quark sea are broken, {\it i.e.} $\Delta\ubar < \Delta \dbar$ and $\Delta s < \Delta \sbar$. The polarization of the strange sea is found to be positive, which is in contradiction to previous analyses. We predict a much larger quark-antiquark asymmetry in the polarized strange quark sea than that in the unpolarized strange quark sea. Our results for both polarized light quark sea and polarized strange quark sea are consistent with the recent HERMES data.