论文标题
在随机平均场进近内强抑制重型离子碰撞中的动能耗散和波动
Kinetic energy dissipation and fluctuations in strongly-damped heavy-ion collisions within the stochastic mean-field approach
论文作者
论文摘要
背景：微观平均场方法已经成功地描述了低能量重离子反应中最可能的反应结果。但是，已知这些方法严重低估了围绕其适用性的平均值的可观测值分散。最近，已经表明，基于随机平均场（SMF）理论的定量传输方法显着改善了描述，而其应用迄今已限制在碎片质量和电荷分散体中。 目的：在这项工作中，我们基于SMF理论扩展了数量转运方法，以在低能量重型离子反应中的相对动能耗散和角动量转移。 结果：作为拟议形式主义的第一个应用，我们考虑了径向线性动量分散体，忽略了径向和角动量之间的耦合。我们分析了$^{136} $ XE+$^{208} $ pb反应在$ e_ \ mathrm {c.m。} = 526 $ MEV中的二进制反应产物的总动能（TKE）分布。从TDHF中的单粒子轨道的时间演变起，径向扩散系数是在微观的基础上计算出来的，而对径向摩擦系数进行了现象学处理。通过求解径向线性动量的量化扩散方程，可以获得径向线性动量的分散体，从中可以构建TKE分布。我们发现计算对大量能源损失值的TKE分布提供了很好的描述，TKEL $ \ gtrsim $ 150 MEV。但是，计算低估了较小能量损失的TKE分布。需要进一步的研究来改善计算的技术细节。 （由于单词限制而缩短）
Background: Microscopic mean-field approaches have been successful in describing the most probable reaction outcomes in low-energy heavy-ion reactions. However, those approaches are known to severely underestimate dispersions of observables around the average values that has limited their applicability. Recently it has been shown that a quantal transport approach based on the stochastic mean-field (SMF) theory significantly improves the description, while its application has been limited so far to fragment mass and charge dispersions. Purpose: In this work, we extend the quantal transport approach based on the SMF theory for relative kinetic energy dissipation and angular momentum transfer in low-energy heavy-ion reactions. Results: As the first application of the proposed formalism, we consider the radial linear momentum dispersion, neglecting the coupling between radial and angular momenta. We analyze the total kinetic energy (TKE) distribution of binary reaction products in the $^{136}$Xe+$^{208}$Pb reaction at $E_\mathrm{c.m.}=526$ MeV and compare with experimental data. From time evolution of single-particle orbitals in TDHF, the radial diffusion coefficient is computed on a microscopic basis, while a phenomenological treatment is introduced for the radial friction coefficient. By solving the quantal diffusion equation for the radial linear momentum, the dispersion of the radial linear momentum is obtained, from which one can construct the TKE distribution. We find that the calculations provide a good description of the TKE distribution for large values of energy losses, TKEL $\gtrsim$ 150 MeV. However, the calculations underestimate the TKE distribution for smaller energy losses. Further studies are needed to improve the technical details of calculations. (Shortened due to the word limit)
