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在高倍率的b夸克哈德龙化中修改的证据pp碰撞在sqrt[s]=13TeV时碰撞
R Aaij1, A S W Abdelmotteleb2, C Abellan Beteta3
1Nikhef National Institute for Subatomic Physics, Amsterdam, Netherlands.
Physical review letters
|August 25, 2023
概括
在LHCb实验中观察到,美奇 (B_{s}^{0}) 与美性 (B^{0}) 中子生成的比率在质子对质子碰撞中随着低横动量的粒子多样性而增加. 这表明,哈德龙介质密度可能会影响B介质子生产率.
科学领域:
- 高能物理 高能物理
- 粒子物理学 粒子物理学
- 量子色态动力学 量子色态动力学
背景情况:
- 了解重夸克的产生对于测试量子染色动力学至关重要.
- B介质子 (B_{s}^{0}和B^{0}) 的生产速度可能对碰撞环境敏感.
研究的目的:
- 测量B_{s}^{0}等离子相对于B^{0}等离子的生产率.
- 为了研究这个比率对充电粒子的多重性和横向动量的依赖.
主要方法:
- 分析了由LHCb实验收集的质子对质子碰撞数据,该实验的质量中心能量为13 TeV.
- 在前进速度间隔 (2 < y < 4.5) 进行的测量.
- 作为充电粒子多重性和横向动量的函数的比率的研究.
主要成果:
- 在3.4σ级别的证据表明B_{s}^{0}/B^{0}截面比增加,横向矩的倍数低于6GeV/c.
- 在较高的横向动量时没有观察到显著的多重性依赖.
- 与e^{+}e^{-}碰撞数据的比较表明,哈德龙介质密度的潜在作用.
结论:
- 观察到的B介质子生成的多重性依赖性在质上与高多重性碰撞中的夸克凝聚相一致.
- 哈德龙介质密度可能会影响重质子生产率.
- 需要进行进一步的研究,才能充分理解所起作用的哈德龙化机制.
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