AI 中文总结
研究采用带夸克的线性σ模型，计算恒定均匀磁场下夸克-中性π介子顶点的树图及单圈修正，结果在Ritus形式论与施温格固有时间方法下一致，适用于夸克占据任意朗道能级的情况。
AI 中文摘要
我们采用带夸克的线性σ模型作为QCD的低能有效理论，计算了由恒定均匀磁场诱导的夸克-中性π介子顶点的修正。即使在树图水平，该顶点也会发生修正，因为平移不变性的缺失使得计算需在坐标空间中进行，夸克由Ritus波函数而非平面波描述。我们还计算了单圈顶点修正，这些修正适用于夸克占据任意朗道能级的情况，并以夸克占据最低朗道能级为例展示了结果。为验证该结果，我们采用施温格固有时间方法，在夸克占据最低朗道能级的情况下计算了单圈顶点修正，得到了与使用Ritus形式论时相同的结果。
英文摘要
We compute the modification to the quark-neutral pion vertex, induced by a constant and uniform magnetic field, using the Linear Sigma Model with quarks as a low energy effective theory of QCD. The vertex is modified even at tree-level since, due to the loss of translational invariance, the calculation should be carried out in configuration space, with the quark described by Ritus wave functions instead of plane waves. We also compute the one-loop vertex modification. These modifications are found for arbitrary Landau levels occupied by the quark. We illustrate the result for the case where the quark occupies the lowest Landau level. To check the result, we also compute the one-loop vertex modification using the Schwinger proper-time method with the quark occupying the lowest Landau level and find the same result as in the case where the Ritus formalism is used.
Comments19 pages, 4 figures
