N-圈传播子极点漂移小量换序计算

Pole Drifting Infinitesimal of Loop Propagator by Changing the Calculating Order

采用核子N(反核子N)与中性介子π0相互作用的Lorentz不变耦合模型,对N-圈图传播子在动量重整化方案中的有限量函数∑c(p)的严格解析计算问题,从极点漂移小量ε作换序计算角度进行了深入的分析、探讨后,发现传播子四维动量平方P2>-(核子质量+介子质量)2时可作合理换序计算处理.若将此计算结果延拓到P2≤-(核子质量+介子质量)2时,发现与正规计算方法获得的计算结果近似符合程度并非十分理想.

After analyzing the finite quantity function ∑c（p） of the N - N loop propagator in the momentum renormalization by changing the calculating order of the pole drifting infinitesimal in Lorentz invariant coupling model of the interaction between nucleon N （ antinucleon N） and neutral meson ,π^0, we find that we can use order-changing calculation to deal with the propagator when the square of four dimensional momentum p^2〉-（m ＋μ）^2（ m-the mass of nucleon, μ- the mass of meson）. It makes not only strictly analytic calculation of ∑c（p） simple, but also the result accord with the one obtained by normal calculational methods. However, both of them cannot match very well when p^2≤ -（m ＋μ）^2.