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在pp的高倍率喷射中观察了增强的远程圆形异位,在sqrt[s]=13 TeV的碰撞中
A Hayrapetyan1, A Tumasyan1, W Adam2
1Yerevan Physics Institute, Yerevan, Armenia.
Physical review letters
|October 18, 2024
概括
研究人员探索了来自质子对质子碰撞的粒子喷射中的集体效应. 在高粒子多样性时,喷气异构的上升趋势表明了目前模型无法解释的潜在集体行为.
科学领域:
- 高能粒子物理学 高能粒子物理学
- 量子染色动力学 (QCD) 是一个
- 强子对撞机物理学 强子对撞机物理学
背景情况:
- 喷气体是高能碰撞中产生的颗粒的聚合喷雾.
- 了解喷气结构和动态对于测试QCD至关重要.
- 通常在重离子碰撞中看到的集体效应,正在像喷气这样的较小系统中进行研究.
研究的目的:
- 为了寻找在质子对质子碰撞中产生的喷气体内集体效应的证据.
- 为了研究喷气性质对喷气内充电粒子多重性的依赖.
- 将实验观测与蒙特卡洛事件发生器预测进行比较.
主要方法:
- 使用LHC的CMS探测器对喷气体内的带电粒子相关性进行分析.
- 使用反-k_T算法 (R=0.8) 重建高横动量 (pT>550 GeV) 的喷气.
- 从长距离的亚齐木斯相关关系 (dakdaη*dakda>2) 中提取福里埃波 (v2*) 作为内射频率 (Nchj) 的函数.
主要成果:
- 观察到圆形异型波 (v2*) 的下降趋势,低倍数的 Nchj 增加.
- 这种下降趋势与蒙特卡洛事件发生器模拟相一致.
- 对于Nchj 80,出现了v2*的上升趋势,这表明测试模型无法重现的集体行为可能出现.
结论:
- 在高Nchj上升的v2*趋势表明从简单的喷气碎片化偏离,暗示集体现象.
- 这一观测为真空中喷气演变的复杂动力学提供了新的见解.
- 需要进一步的理论和实验研究才能充分理解这种新出现的行为.
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