A review is given on the studies of formation of light clusters and heavier fragments in heavy-ion collisions at incident energies from several tens of MeV/nucleon to several hundred MeV/nucleon, focusing on dynamical aspects and on microscopic theoretical descriptions. Existing experimental data already clarify basic characteristics of expanding and fragmenting systems typically in central collisions, where cluster correlations cannot be ignored. Cluster correlations appear almost everywhere in excited low-density nuclear many-body systems and nuclear matter in statistical equilibrium where the properties of a cluster may be influenced by the medium. On the other hand, transport models to solve the time evolution have been developed based on the single-nucleon distribution function. Different types of transport models are reviewed putting emphasis both on theoretical features and practical performances in the description of fragmentation. A key concept to distinguish different models is how to consistently handle single-nucleon motions in the mean field, fluctuation or branching induced by two-nucleon collisions, and localization of nucleons to form fragments and clusters. Some transport codes have been extended to treat light clusters explicitly. Results indicate that cluster correlations can have strong impacts on global collision dynamics and correlations between light clusters should also be taken into account.

中文翻译：

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重离子碰撞中簇和碎片的动力学

综述了在入射能量从几十 MeV/核子到几百 MeV/核子的重离子碰撞中形成轻团簇和较重碎片的研究，重点是动力学方面和微观理论描述。现有的实验数据已经阐明了通常在中心碰撞中扩展和分裂系统的基本特征，其中集群相关性不能被忽略。在激发态的低密度核多体系统和处于统计平衡状态的核物质中，簇的相关性几乎无处不在，其中簇的特性可能会受到介质的影响。另一方面，已经基于单核子分布函数开发了解决时间演化的输运模型。回顾了不同类型的运输模型，在碎片化的描述中强调了理论特征和实际性能。区分不同模型的一个关键概念是如何一致地处理平均场中的单核子运动、两核子碰撞引起的波动或分支，以及核子定位以形成碎片和簇。一些传输代码已被扩展以明确处理轻簇。结果表明，集群相关性会对全局碰撞动力学产生强烈影响，还应考虑轻集群之间的相关性。由两个核子碰撞引起的波动或分支，以及核子定位形成碎片和簇。一些传输代码已被扩展以明确处理轻簇。结果表明，集群相关性会对全局碰撞动力学产生强烈影响，还应考虑轻集群之间的相关性。由两个核子碰撞引起的波动或分支，以及核子定位形成碎片和簇。一些传输代码已被扩展以明确处理轻簇。结果表明，集群相关性会对全局碰撞动力学产生强烈影响，还应考虑轻集群之间的相关性。