Measurement of the nuclear modification factor for muons from charm and bottom hadrons in Pb+Pb collisions at 5.02 TeV with the ATLAS detector
Measurement of the nuclear modification factor for muons from charm and bottom hadrons in Pb+Pb collisions at 5.02 TeV with the ATLAS detector
复制标题
使用 ATLAS 探测器测量 5.02 TeV 的 Pb Pb 碰撞中来自粲子和底强子的 μ 子的核修正因子
DOI：
10.1016/j.physletb.2022.137077
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发表时间：
2022
影响因子：
4.4
通讯作者：
Aad G
中科院分区：
文献类型：
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作者：
Aad G
重味强子的产生提供了关于超相对论重离子碰撞中产生的夸克-胶子等离子体的输运性质和微观结构的信息。本文报道了在大型强子对撞机上用ATLAS探测器测量了在核子-核子质心能量为5.02TeV的Pb+ Pb和pp碰撞中产生的粲强子和底强子的半轻子衰变中的μ子。Pb+ Pb数据分别于2015年和2018年采集，采样积分光度分别为208 μ B− 1和38 μ B− 1，pp数据于2017年采集，采样积分光度为1.17 pB− 1。利用内探测器和μ子谱仪测量之间的动量不平衡，将重味半轻子衰变的μ子从轻味强子背景中分离出来，并通过μ子轨道的横向碰撞参数进一步分离来自粲衰变和底衰变的μ子。在绝对赝快度区间内，测量了这类μ子在Pb+ Pb碰撞中的微分产额和在pp碰撞中的微分截面随μ子横动量的变化| η| < 2。在Pb+ Pb碰撞中心间隔内，给出了粲μ子和底μ子的核修正因子随μ子横动量的变化。底部μ子的结果是最精确的测量B夸克核修改在低横动量的B强子的重建是具有挑战性的。测得的核修改因素量化的魅力和底强子衰变的μ子的产量显着抑制，与魅力强子衰变的μ子更强的影响。
Heavy-flavour hadron production provides information about the transport properties and microscopic structure of the quark–gluon plasma created in ultra-relativistic heavy-ion collisions. A measurement of the muons from semileptonic decays of charm and bottom hadrons produced in Pb+ Pb and pp collisions at a nucleon–nucleon centre-of-mass energy of 5.02 TeV with the ATLAS detector at the Large Hadron Collider is presented. The Pb+ Pb data were collected in 2015 and 2018 with sampled integrated luminosities of 208 μ b− 1 and 38 μ b− 1, respectively, and pp data with a sampled integrated luminosity of 1.17 pb− 1 were collected in 2017. Muons from heavy-flavour semileptonic decays are separated from the light-flavour hadronic background using the momentum imbalance between the inner detector and muon spectrometer measurements, and muons originating from charm and bottom decays are further separated via the muon track's transverse impact parameter. Differential yields in Pb+ Pb collisions and differential cross sections in pp collisions for such muons are measured as a function of muon transverse momentum from 4 GeV to 30 GeV in the absolute pseudorapidity interval| η|< 2. Nuclear modification factors for charm and bottom muons are presented as a function of muon transverse momentum in intervals of Pb+ Pb collision centrality. The bottom muon results are the most precise measurement of b quark nuclear modification at low transverse momentum where reconstruction of B hadrons is challenging. The measured nuclear modification factors quantify a significant suppression of the yields of muons from decays of charm and bottom hadrons, with stronger effects for muons from charm hadron decays.