论文标题
wist-4的电子正电子歼灭过程中的前向反向不对称
The forward-backward asymmetry in the electron positron annihilation process at twist-4
论文作者
论文摘要
一定数量的特定实验兴趣是在$ z^0 $衰变中产生的正面和负电荷的费米子的角度分布中的前向不对称。这种不对称的测量可以独立地确定这些费米子的中性耦合，即分别用于左手和右手费米子的$ z^0 $玻色子耦合。然而，由于夸克限制，很难确定夸克的电动相互作用，尤其是对于轻夸克。在强子生产电子正电子歼灭过程中，具有分解定理的Parton模型给出了可靠的近似描述。因此，数量是根据歼灭过程中的碎片功能表示的。在本文中，我们考虑了在包含电子正电子歼灭过程中的媒介膜产生，并计算出望态水平的前向反向不对称。计算是通过在Parton模型中以领先顺序Twist-4应用共线扩展进行计算。我们在这里注意到，此过程不仅提供了分析HADRONIC弱相互作用的工具，而且还提供了理解强相互作用的Parton模型的机会。换句话说，结果可用于同时测试电子和强相互作用。
A quantity of particular experimental interest is the forward-backward asymmetry in the angular distribution of positively and negatively charged fermions produced in $Z^0$ decays. Measurements of this asymmetry can enable independent determinations of the neutral-current couplings of these fermions, i.e. the $Z^0$ boson couplings for left- and right-handed fermions, respectively. Due to the quark confinement, however, it is difficult to determine the electroweak interactions of quarks, especially for light quarks. In the hadron production electron positron annihilation process, the parton model with factorization theorem gives a reliable approximate description. Quantities are thus expressed in terms of fragmentation functions in the annihilation process. In this paper, we consider the vector meson production in the inclusive electron positron annihilation process and calculate the forward-backward asymmetry in the hadronic level. Calculations are carried out by applying the collinear expansion in the parton model at leading order twist-4. We note here this process provides not only a tool for analyzing the hadronic weak interactions but also an opportunity for understanding the parton model of the strong interaction. In other words, the results can be used to test the electroweak and strong interactions simultaneously.
