论文标题
从核巨型偶极子共振的宽度上限制中核内核子内核子横截面
Constraining the in-medium nucleon-nucleon cross section from the width of nuclear giant dipole resonance
论文作者
论文摘要
我们开发了一种新的晶格哈密顿方法来解决Boltzmann-Uehling-uhlenbeck（BUU）方程。采用随机方法来治疗碰撞项并使用GPU并行计算进行计算，可以在评估碰撞项时具有相当高的精度，尤其是其Pauli阻塞，从而导致了解决BUU方程式的新水平。应用这种晶格BUU方法研究核中巨大偶极共振（GDR）的宽度，在该细胞核中，准确处理碰撞项至关重要，我们发现获得的GDR宽度为$^{\ rm pb} {\ rm pb} $，表明对内核核子核子crossleon-nucleon-nucleon-nucle-nucle-nucleon cross $ $ $ $ $ $ nsn*。需要在日本奥萨卡Osaka的核核物理学研究中心，需要大量的$σ_ {\ rm nn}^*$来重现$^{208} {\ rm pb} $的GDR宽度的测量值。
We develop a new lattice Hamiltonian method for solving the Boltzmann-Uehling-Uhlenbeck (BUU) equation. Adopting the stochastic approach to treat the collision term and using the GPU parallel computing to carry out the calculations allows for a rather high accuracy in evaluating the collision term, especially its Pauli blocking, leading thus to a new level of precision in solving the BUU equation. Applying this lattice BUU method to study the width of giant dipole resonance (GDR) in nuclei, where the accurate treatment of the collision term is crucial, we find that the obtained GDR width of $^{208}{\rm Pb}$ shows a strong dependence on the in-medium nucleon-nucleon cross section $σ_{\rm NN}^*$. A very large medium reduction of $σ_{\rm NN}^*$ is needed to reproduce the measured value of the GDR width of $^{208}{\rm Pb}$ at the Research Center for Nuclear Physics in Osaka, Japan.
