πNN过程对Gottfried求和规则破坏的贡献

Contribution of the πNN Processes to Gottfried Sum Rule Violation

指出在计算πNN过程对核子结构函数的贡献时 ,将反冲核子视为物理核子更为合理 .对Gottfried求和规则破坏、对质子中海夸克分布u和d不对称u(x) -d(x)等方面的贡献给出了详细的计算 ,与已有实验进行比较 .结果表明π介子交换不是导致这一破坏以及影响核子结构函数的效应的惟一来源 .

It is pointed out that contribution of the πNN processes to the structure functions of the nucleon should be calculated by taking the recoil nucleon as a physical nucleon. The obtained result for the contribution to Gottfried sum rule violation is smaller than the corresponding result obtained earlier in literature, where Gottfried sum rule was assumed to be valid for the recoil nucleon. It leaves more space to other mechanisms leading to such violation. Some other consequences are also discussed in this paper.==