中文摘要：

计算了DDσ相互作用的形状因子和耦合常数.为了把D0介子具有内部结构的效应考虑进去,用Bethe-Salpeter振幅来描述重介子态.夸克流在重介子态之间的矩阵元通过Mandelstam修正过的Gell-Mann-Low方法计算.对于这一方法所要求的Bethe-Salpeter不可约核,采用了最低阶近似.在得到DDσ相互作用的形状因子后,计算了DDσ的耦合常数.

英文摘要：

The form factor and coupling constant for vertex DDaare calculated. For taking into account the inner structure of DO meson. The Bethe-Salpeter amplitude is adopted to describe the heavy meson states. The Mandelstam generalization of the Gell-Mann-Low methods is applied to calculate the matrix element of quark current between the heavy meson states. The lowest order approximation is taken for the Bethe-Salpeter irreducible kernel which is required by the Mandelstam generalization of the Gell- Mann-Low method. After obtaining the DDσ form factor, the DDσ coupling constant is worked out.