Utlizing the factorizing F operator in the quantum space,the scalar products of the Bethe states are directly calculated and the Gaudin formula is proved for the case of XXX 12 spin chain under the integrable open boundary condition.

• 利用量子空间可因式化F算子 ；在量子反散射的框架内计算出了可积开边界条件下XXX 12 自旋链模型的Bethe态的标量积和模 ；得到了用谱参量函数的行列式表达的开边界条件下的Gaudin公式 .