论文标题
晶格哈密顿法中运输模型中的核集体动力学
Nuclear collective dynamics in transport model with the lattice Hamiltonian method
论文作者
论文摘要
我们通过解决Boltzmann-Uehling-Uhlenbeck（BUU）方程来研究核集体动力学的最新进展，并使用晶格汉密尔顿方法通过完整的随机碰撞方法处理碰撞项。该晶格BUU（LBUU）方法最近在GPU并行计算技术中开发和实施，并在评估核素核子（NN）碰撞项时达到了相当稳定的核基态进化和高精度。这种新的LBUU方法已应用于研究核等速镜巨型单极共振和等分子巨型偶极子共振。虽然没有NN碰撞项的LBUU方法计算（即，晶格Hamiltonian Vlasov方法）合理地描述了核巨头共振的激发能量，但完整的LBUU计算可以很好地重现$^{208} $ pb的巨型偶极共振的宽度。观察到的核巨型偶极子共振的宽度与NN弹性横截面之间的强相关性表明，NN弹性散射在核集体动力学中起着重要作用，而核巨型偶极子共振的宽度为中等内膜内弹性横截面提供了良好的概率。
We review the recent progress on studying the nuclear collective dynamics by solving the Boltzmann-Uehling-Uhlenbeck (BUU) equation with the lattice Hamiltonian method treating the collision term by the full-ensemble stochastic collision approach. This lattice BUU (LBUU) method has recently been developed and implemented in a GPU parallel computing technique, and achieves a rather stable nuclear ground-state evolution and high accuracy in evaluating the nucleon-nucleon (NN) collision term. This new LBUU method has been applied to investigate the nuclear isoscalar giant monopole resonances and isovector giant dipole resonances. While the calculations with the LBUU method without the NN collision term (i.e., the lattice Hamiltonian Vlasov method) describe reasonably the excitation energies of nuclear giant resonances, the full LBUU calculations can well reproduce the width of the giant dipole resonance of $^{208}$Pb by including a collisional damping from NN scattering. The observed strong correlation between the width of nuclear giant dipole resonance and the NN elastic cross section suggests that the NN elastic scattering plays an important role in nuclear collective dynamics, and the width of nuclear giant dipole resonance provides a good probe of the in-medium NN elastic cross section.
