许俊怀,肖志刚

• 1:清华大学物理系

摘要(Abstract)：

原子核由质子和中子构成，组成原子核的质子和中子大多数时候受整体核力环境支配并产生运动，通常称之为费米运动。这些中子和质子，偶尔会在极短距离内形成转瞬即逝的“搭档”，并获得异常大的相对动量，物理学家称之为短程关联。这样的搭档不能被直接“拍照”，却会在重离子碰撞早期留下线索：跑得特别快的中子和质子相遇时，更容易放出高能伽马光子，使伽马能谱的高能端被抬高、变“硬”。近期的锡-锡碰撞实验利用这一线索，通过测量碰撞产生的高能轫致辐射光子，结合输运模型、探测器校准和背景检验，推断锡-124原子核中约20%的核子具有与短程关联相关的高动量成分。该结果为研究原子核内部短距离运动提供了一种新的、与电子散射和强子敲出互补的方法，也让低能重离子碰撞成为探测核内核子运动形态与基态核结构特征的新窗口。

关键词(KeyWords)： 短程关联;高动量尾巴;轫致辐射伽马射线;重离子碰撞

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金项目（12335008）

作者(Author): 许俊怀,肖志刚

DOI: 10.27024/j.wlygc.2026.06.29.is

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