论文标题
介子过渡形式因素的渐近行为
Asymptotic behavior of meson transition form factors
论文作者
论文摘要
评估从辐射光线散射到MUON $（G-2）_ $的异常磁矩的贡献的开放问题之一是涉及较重的标量，轴向矢量和张量的MESON中间状态的作用。 Landau-Yang定理抑制了轴向矢量与虚拟光子的耦合，但在相应的形态上几乎没有严格的约束。在本文中，我们首先将两光矩阵元素的洛伦兹分解为标量函数，该函数是Bardeen，Tung和Tarrach的一般配方之后的。基于这种分解，我们随后计算了介子过渡的渐近行为，该渐近型从轻度膨胀与Brodsky和Lepage得出的伪级过渡形式的渐近极限类似。最后，我们将结果与现有数据以及文献中使用的先前模型进行了比较。
One of the open issues in evaluations of the contribution from hadronic light-by-light scattering to the anomalous magnetic moment of the muon $(g-2)_μ$ concerns the role of heavier scalar, axial-vector, and tensor-meson intermediate states. The coupling of axial vectors to virtual photons is suppressed for small virtualities by the Landau-Yang theorem, but otherwise there are few rigorous constraints on the corresponding form factors. In this paper, we first derive the Lorentz decomposition of the two-photon matrix elements into scalar functions following the general recipe by Bardeen, Tung, and Tarrach. Based on this decomposition, we then calculate the asymptotic behavior of the meson transition form factors from a light-cone expansion in analogy to the asymptotic limits for the pseudoscalar transition form factor derived by Brodsky and Lepage. Finally, we compare our results to existing data as well as previous models employed in the literature.
