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在LHC的超相对论 ^{129}Xe+^{129}Xe碰撞中探索核形状相变
Shujun Zhao1,2, Hao-Jie Xu2,3, You Zhou4
1School of Physics, <a href="https://ror.org/02v51f717">Peking University</a>, Beijing 100871, China.
Physical review letters
|November 22, 2024
概括
核形状转换揭示了Xenon-129同位素中的γ-软变形. 新的相关系数可以在重离子碰撞中区分γ-软和刚三轴形状.
科学领域:
- 核物理 核物理 核物理
- 高能核碰撞 高能核碰撞
- 量子相位过渡 量子相位过渡
背景情况:
- 与有限核中的量子相过渡相关的核形状相过渡是核物理中的关键现象.
- (Xe) 同位素链表现出从玛软旋转器到球形振动器的过渡,与Xe-128-130附近的第二阶段形状过渡.
- 了解Xe-129的γ-软变形对于研究这种二次形状相位过渡至关重要.
研究的目的:
- 为了研究Xe-129的γ-软变形在第二阶段形状相转换的背景下.
- 在超相对论Xe-129+Xe-129碰撞中开发和利用新型的相关系数来探测核结构.
- 使用先进的关联器技术,区分Xe-129的γ-软和刚三轴变形.
主要方法:
- 构建新的相关系数,包括 ρ_{4,2} 和 ρ_{2,4},旨在捕获更高阶的相关性.
- 使用iEBE-VISHNU模型进行超相对论 Xe-129 + Xe-129碰撞的计算.
- 分析圆流 (v2) 与平均横动量 ([p_{T}]),表示为 ρ2,以及 [p_{T}] 波动 (Γ_{p_{T}}) 之间的相关性.
主要成果:
- 计算表明,先前观察到的相关性 (ρ2 和 Γ_{p_{T}}) 可以通过γ-软变形来解释,而不是完全硬的三轴变形.
- 新提出的相关系数, ρ_{4,2} 和 ρ_{2,4},在区分γ-软和刚三轴变形方面表现出独特的能力.
- 这些发现表明,g-软变形为Xe-129中观察到的现象提供了可行的解释.
结论:
- 该研究成功地表明,Xe-129的γ-软变形可以解释以前归因于刚性三轴性的实验观测结果.
- 新型对应器提供了一种强大的新工具,用于在重离子碰撞实验中探测和区分不同的核形状.
- 这项研究提出了一种新的方法来探索有限核中的二次形状相转换,使用LHC的超相对论重离子碰撞.
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