论文标题
在$ \ sqrt {s sqrt {s} = 13 $ tev的$ w^{\ pm} z $生产中观察量表玻色子联合化状态。
Observation of gauge boson joint-polarisation states in $W^{\pm}Z$ production from $pp$ collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector
论文作者
论文摘要
提出了$ W $和$ Z $量规玻色子的$ W^{\ pm} Z $生产中的联合极化状态的测量。所使用的数据集对应于质子 - 质子碰撞的$ 139 $ fb $^{ - 1} $的集成发光度，该质量碰撞是在Cern大型强子对撞机的Atlas detector记录的$ 13 $ TEV的质量中心能量。 $ w^{\ pm} z $候选事件是使用量规玻色子的轻质衰减模式重建的，以电子和穆斯元素为单位。首次测量纵向载体玻色子的同时成对生产，其显着性为$ 7.1 $标准偏差。在基准区域集成的测量的联合螺旋分数为$ f _ {\ mathrm {00}} = 0.067 \ pm 0.010 $，$ f _ {\ mathrm {0t}} = 0.110 = 0.110 \ pm 0.029 $，pm 0.029 $，$ f _ {$ f _ { $ f _ {\ mathrm {tt}} = 0.644 \ pm 0.032 $，与次要领先的标准模型预测一致。还测量了$ W $和$ Z $玻色子的单个螺旋分数，并且发现与预期相关金额内的联合螺旋分数一致。联合和单个螺旋分数也分别以$ W^+Z $和$ W^-z $事件分别测量。提出了对极化敏感的几个运动学观察值的包含和差分横截面。
Measurements of joint-polarisation states of $W$ and $Z$ gauge bosons in $W^{\pm}Z$ production are presented. The data set used corresponds to an integrated luminosity of $139$ fb$^{-1}$ of proton-proton collisions at a center-of-mass energy of $13$ TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. The $W^{\pm}Z$ candidate events are reconstructed using leptonic decay modes of the gauge bosons into electrons and muons. The simultaneous pair-production of longitudinally polarised vector bosons is measured for the first time with a significance of $7.1$ standard deviations. The measured joint helicity fractions integrated over the fiducial region are $f_{\mathrm{00}} = 0.067 \pm 0.010$, $f_{\mathrm{0T}} = 0.110 \pm 0.029$, $f_{\mathrm{T0}} = 0.179 \pm 0.023$ and $f_{\mathrm{TT}} = 0.644 \pm 0.032$, in agreement with the next-to-leading-order Standard Model predictions. Individual helicity fractions of the $W$ and $Z$ bosons are also measured and found to be consistent with joint helicity fractions within the expected amount of correlations. Both the joint and individual helicity fractions are also measured separately in $W^+Z$ and $W^-Z$ events. Inclusive and differential cross sections for several kinematic observables sensitive to polarisation are presented.
