We have performed a study of the isovector, octet, and singlet axial charges of the proton in an extended chiral constituent quark model, where all the possible $uudq\overline{q}$ ($q=u$, $d$, $s$) five-quark Fock components in the proton wave function are taken into account. The ${}^3{P}_0$ quark-antiquark creation mechanism is assumed to account for the transition coupling between three- and five-quark components in proton, and the corresponding transition coupling strength is fixed by fitting the intrinsic sea flavor asymmetry $\overline{d}-\overline{u}$ data for proton. Accordingly, with all the parameters fixed by empirical values, the probabilities of the intrinsic five-quark Fock components in proton wave function should be $\sim 30–50\%$, which lead to the numerical results for quark spin $\mathrm{\Delta }u$, $\mathrm{\Delta }d$, and $\mathrm{\Delta }s$, as well the axial charges of proton consistent with the experimental data and predictions by other theoretical approaches.

中文翻译：

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扩展手性成分夸克模型中质子的轴向电荷

我们在扩展的手性成分夸克模型中对质子的等向量、八位组和单重轴电荷进行了研究，其中所有可能的 $你你dq\overline{q}$ ($q=你$, $d$, $秒$) 考虑了质子波函数中的五夸克福克分量。这${}^3{磷}_0$ 假设夸克-反夸克的产生机制解释了质子中三夸克和五夸克成分之间的跃迁耦合，并且通过拟合固有的海味不对称性来确定相应的跃迁耦合强度 $\overline{d}-\overline{你}$质子的数据。因此，在所有参数由经验值固定的情况下，质子波函数中固有五夸克福克分量的概率应为$～30\mathrm{——}50\%$，这导致夸克自旋的数值结果 $\mathrm{\Delta }你$, $\mathrm{\Delta }d$， 和 $\mathrm{\Delta }秒$，以及质子的轴向电荷与其他理论方法的实验数据和预测一致。