标题： 核力与核激发态 显示英文标题

标题： Nuclear forces and nuclear excited states

摘要： 本工作中研究了双核子相互作用中的中心力、自旋-力和张量力在 20 个 sd 壳核素的第一激发态 2$^+$和 4$^+$中的作用。计算是在核壳模型的框架内完成的。结果显示中心力对激发能的贡献占主导地位，而自旋-轨道力和张量力的贡献相对较小，但在某些情况下（如$^{22}$O）其作用被注意到是至关重要的。此外，还证明了哈密顿投影方法应优先用于正确评估每种力对激发能的贡献。 显示英文摘要

摘要： In this work, the role of the central, spin-force and tensor forces of two-nucleon interaction in building the first 2$^+$ and 4$^+$ states of 20 sd-shell nuclei is studied. Calculations are performed within the framework of the nuclear shell model. It is shown that the central force predominantly contributes to the excitation energy. While the spin-orbit and tensor forces contribute relatively less, their roles are noted crucial in a few cases, such as in $^{22}$O. Further, it is demonstrated that the Hamiltonian projection approach should be preferred for rightly assessing the contributions of each force to the excitation energy.