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讨论了核结构模型中两体以上相互作用的可能形式.首先以基于手征微扰论并适于描述轻核的三体接触型相互作用为例,讨论了能合理描述3H和3He结合能的三核子接触型相互作用相关的两个低能有效耦合参数cD和cE间的关系并通过4He结合能给出了相应的物理参数区.其次通过Okubo-Lee-Suzuzki有效相互作用方法对核多体问题在有限模型空间的求解,论证了A-体相互作用项.最后利用包含了A-体推广对力的可解模型对重核的同位素长链进行了分析.以132Sn为核芯,通过对Sn同位素链的计算揭示了推广对力参数G(A)与模型价核子空间维数dim(A)间的显著关系:G(A)=259.436 dim(A)-0.9985.这些分析结果说明,有必要对核中经手征微扰论或其它唯象理论所得到的NNN-,NNNN-,及A-体相互作用作进一步的研究.“,”We discuss modeling of nuclear structure beyond the 2-body interaction paradigm.Our first example is related to the need of three nucleon contact interaction terms suggested by chiral perturbation theory.The relationship of the two low-energy effective coupling parameters for the relevant three nucleon contact interaction terms cD and cE that reproduce the binding energy of 3H and 3He has been emphasized and the physically relevant parameter region has been ilustrated using the binding energy of 4He.Further justification of A-body interaction terms is outlined based on the Okubo-Lee-Suzuki effective interaction method used in solving the nuclear many-body problem within a finite model space.The third example we use is an exactly solvable A-body extended paring interaction applied to heavy nuclei with a long isotopic chain;in particular using 132Sn as closed core system illustrates a remarkable relationship between the extended pairing strength G(A) and the size of the valence space dim(A) for the members of the Sn-isotope chain:G(A) =c dim(A)-β with α =259.436 andβ =0.998 5 which is actually a one parameter expression since β is practically 1.These three cases present evidence for the need of better understanding of the NNN-,NNNN-,and A-body interactions in nuclei either derived from ChPT or from a phenomenological considerations.